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ABSTRACT Objectives Material and Methods Results Conclusions Trial Registration This controlled preclinical study analyzed the effect of implant surface characteristics on osseointegration and crestal bone formation in a grafted dehiscence defect minipig model.A standardized 3 mm × 3 mm acute‐type buccal dehiscence minipig model grafted with deproteinized bovine bone mineral and covered with a porcine collagen membrane after 2 and 8 weeks of healing was utilized. Crestal bone formation was analyzed histologically and histomorphometrically to compare three implant groups: (1) a novel, commercially available, gradient anodized (NGA) implant, to two custom‐made geometric replicas of implant “1,” (2) a superhydrophilic micro‐rough large‐grit sandblasted and acid‐etched surface, and (3) a relatively hydrophobic micro‐rough large‐grit sandblasted and acid‐etched surface.At 2 and 8 weeks, there was no difference between the amount and height of newly formed bone (NBH, new bone height; BATA, bone area to total area) for any of the groups (p > 0.05). First bone‐to‐implant contact (fBIC) and vertical bone creep (VBC) at 2 and 8 weeks were significantly increased for Groups 2 and 3 compared to Group 1 (p < 0.05). At 8 weeks, osseointegration in the dehiscence (dehiscence bone‐implant‐contact; dBIC) was significantly higher for Groups 2 and 3 compared to Group 1 (p < 0.05).The amount of newly formed bone (BATA) and NBH was not influenced by surface type. However, moderately rough surfaces demonstrated significantly superior levels of osseointegration (dBIC) and coronal bone apposition (fBIC) in the dehiscence defect compared to the NGA surface at 2 and 8 weeks.For this type of study, clinical trial registration is not required. This study was conducted at the Biomedical Department of Lund University (Lund, Sweden) and approved by the local Ethics Committee of the University (M‐192‐14) [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Methods Results Conclusions This study aimed to explore multiple effects of hyperbranched poly‐l‐lysine (HBPL) titanium (Ti) surfaces on osseointegration, bacteriostasis, and anti‐inflammation across three different animal models.Ti surfaces were covalently modified with HBPL, with uncoated surfaces as controls. Characterization included scanning electron microscopy (SEM) and surface chemistry and elemental analysis (EDX). Ti and Ti‐HBPL implants were placed in conventional canine edentulous sites, post‐operative infection canine edentulous sites, and diabetic rat tibias. Implants from canine edentulous models were analyzed using micro‐CT and histomorphometry to assess osseointegration at 8 weeks. Post‐operative infection beagles were used to evaluate antibacterial efficacy through clinical parameters and bacterial cultures at 1 week. In diabetic rats, micro‐CT and histomorphometry were performed at 8 weeks.HBPL was uniformly grafted on Ti‐HBPL surfaces. Ti‐HBPL surfaces showed higher bone volume/total volume (BV/TV, p < 0.001), bone‐implant contact (BIC%, p < 0.001), and trabecular number (Tb.N, p < 0.01) in beagles. Besides, it displayed higher BIC% (p < 0.001) and bone area fraction occupancy (BAFO%, p < 0.01) in hard tissue sections. In an infected model, Ti‐HBPL surfaces exhibited lower bleeding on probing (BOP, p < 0.001), and plaque index (DI, p < 0.01), with reduced bacterial colony formation (p < 0.001) compared to the control group. In diabetic rats, Ti‐HBPL surfaces showed an increase in BV/TV (p < 0.01) and Tb.N (p < 0.001), downregulated TNF‐α and IL‐1β (p < 0.01), and upregulated IL‐10 (p < 0.01) and osteocalcin (OCN) expression (p < 0.01).HBPL‐Ti surfaces demonstrated enhanced osseointegration, bacteriostasis, and anti‐inflammatory effects in vivo. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to compare a novel tapered, double‐threaded self‐tapping tissue‐Level design implant (TLC) to a well‐established parallel walled tissue‐level (TL) implant in terms of primary and secondary stability over time. Materials and Methods: Test TLC (n = 10/per timepoint) and control TL (n = 10/per timepoint) implants were placed in the mandible of minipigs and left for submerged healing for 3, 6, and 12 weeks. Maximum insertion torque and implant stability quotient (ISQ) were measured for each implant at placement. Osseointegration and cortical bone maintenance were histologically evaluated by measuring total bone‐to‐implant contact (BIC) and first bone‐to‐implant contact (fBIC). Results: A significantly higher maximum insertion torque was measured for the test implant TLC compared to the control TL implant (57.83 ± 24.73 Ncm and 22.62 ± 23.16 Ncm, respectively; p <.001). The mean ISQ values were comparable between the two implant types (75.00 ± 6.70 for TL compared to 75.40 ± 3.20 for TLC, p =.988). BIC was comparable between both implant types at each of the evaluated time points. The fBIC was found to be significantly more coronal at 12 weeks for the TLC implant compared to the TL implant (0.31 ± 0.83 mm for TLC compared to −0.22 ± 0.85 for TL, p =.027). Conclusion: The novel tapered tissue level design implant showed improved primary stability and an overall improved crestal bone height maintenance compared to the parallel walled design at 12 weeks. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to qualitatively and quantitatively evaluate biofilm formation on hybrid titanium implants (HS), with moderately rough and turned surface topographies. Materials and Methods: A validated dynamic in vitro multispecies biofilm model, based on bacterial growth under flow and shear conditions resembling the oral cavity, was used to evaluate biofilm formation on the tested implant surfaces. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to compare the biofilm structure and microbial biomass deposited on either the moderately rough or the turned surface of HS. Quantitative polymerase chain reaction (qPCR) was used to evaluate the total bacterial counts and counts of each specific bacterium in biofilms formed on implants with either the moderately rough or the turned surfaces, as in the hybrid titanium implants, after 24, 48 and 72 h. A general linear model was applied to compare the CLSM and qPCR results between the tested implant surfaces. Results: A significantly higher bacterial biomass grew on the moderately rough implant surfaces, compared to the turned surface area of HS implants (p <.05), at all incubation times, as evidenced with both CLSM and SEM. qPCR analysis also demonstrated an important increase in the total and specific bacterial counts in moderately rough surface implants at the three incubation times. Conclusions: Implant surface topography (moderately rough versus turned) significantly influenced in vitro biofilm formation in terms of biofilm structure, bacterial biomass and quantity of the specific species selected for the model used. [ABSTRACT FROM AUTHOR]

Objectives: Crestal bone formation represents a crucial aspect of the esthetic and biological success of dental implants. This controlled preclinical study analyzed the effect of implant surface and implant geometry on de novo crestal bone formation and osseointegration. Materials and methods: Histological and histomorphometrical analysis was performed to compare three implant groups, that is, (1) a novel, commercially available, gradient anodized implant, (2) a custom‐made geometric replica of implant "1," displaying a superhydrophilic micro‐rough large‐grit sandblasted and acid‐etched surface, and (3) a commercially available implant, having the same surface as "2" but a different implant geometry. The study applied a standardized buccal acute‐type dehiscence model in minipigs with observation periods of 2 and 8 weeks of healing. Results: The amount of newly formed crestal bone (BATA) around control groups (2) and (3) was significantly increased when compared to the test group (1) at the 8 weeks of healing time point. Similar results were obtained for all parameters related to osseointegration and direct bone apposition, to the implant surface (dBIC, VBC, and fBIC), demonstrating superior osseointegration of the moderately rough, compared to the gradient anodized functionalization. After 2 weeks, the osseointegration (nBIC) was found to be influenced by implant geometry with group (3) outperforming groups (1) and (2) on this parameter. At 8 weeks, nBIC was significantly higher for groups (2) and (3) compared to (1). Conclusions: The extent (BATA) of de novo crestal bone formation in the acute‐type dehiscence defects was primarily influenced by implant surface characteristics and their ability to promote osseointegration and direct bone apposition. Osseointegration (nBIC) of the apical part was found to be influenced by a combination of surface characteristics and implant geometry. For early healing, implant geometry may have a more pronounced effect on facilitating osseointegration, relative to the specific surface characteristics. [ABSTRACT FROM AUTHOR]

Background: Inflammation triggered by bacterial biofilms in the surrounding tissue is a major etiological factor for peri‐implantitis and subsequent implant failure. However, little is known about the direct effects of bacterial corrosion and recolonization on implant failure Purpose: To investigate the influence of oral commensals on bacterial corrosion and recolonization of titanium surfaces. Materials and Methods: Streptococcus sanguinis (S. sanguinis) and Porphyromonas gingivalis (P. gingivalis), which are key bacteria in oral biofilm formation, were cultured on commercially pure titanium and titanium‐aluminum‐vanadium (Ti6Al4V) plates in artificial saliva/brain heart infusion medium under aerobic or anaerobic conditions. Biofilm formation was examined after 7 and 21 days by crystal violet and live/dead staining. Titanium ions released into culture supernatants were analyzed over a period of 21 days by atomic absorption spectrometry. Visual changes in surface morphology were investigated using scanning electron microscopy. Biofilm formation on sterilized, biocorroded, and recolonized implant surfaces was determined by crystal violet staining. Results: S. sanguinis and P. gingivalis formed stable biofilms on the titanium samples. Bacterial corrosion led to a significant increase in titanium ion release from these titanium plates (p < 0.01), which was significantly higher under aerobic conditions on pure titanium (p ≤ 0.001). No obvious morphological surface changes, such as pitting and discoloration, were detected in the titanium samples. During early biofilm formation, the addition of titanium ions significantly decreased the number of live cells. In contrast, a significant effect on biofilm mass was only detected with P. gingivalis. Bacterial corrosion had no influence on bacterial recolonization following sterilization of titanium and Ti6Al4V surfaces. Conclusion: Bacterial corrosion differs between oral commensal bacteria and leads to increased titanium ion release from titanium plates. The titanium ion release did not influence biofilm formation or bacterial recolonization under in vitro conditions [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effect of surgical treatment of experimental peri‐implantitis at implants with different surface characteristics using mechanical and chemical decontamination methods. Materials and Methods: Following extraction of mandibular premolars, four implants with two different surface characteristics (A, moderately rough and B, smooth) were placed in each side of the mandible of six dogs. Experimental peri‐implantitis was induced. Surgical treatment of the peri‐implantitis sites was carried out using four implant surface decontamination protocols: (i) deposition of a citric acid gel, (ii) mechanical cleaning using a rotating titanium brush, (iii) a combination of the mechanical and chemical procedures, and (iv) saline (control). Clinical and radiographic examinations were performed. Block biopsies were obtained 6 months after therapy and prepared for histological analysis. Results: Irrespective of the treatment group, treatment resulted in 0.63 ± 0.92 and 0.65 ± 0.67 mm radiographic bone gain around implants A and B, respectively. Histological analyses revealed that persisting soft tissue inflammation as assessed using an infiltrated connective tissue (ICT) score was significantly lower at implant type B than at implant type A for all treatment groups. The test decontamination procedures did not demonstrate better results regarding resolution of peri‐implantitis lesions, as indicated by the ICT scores, than the control procedure. The control treatment resulted in significantly superior outcomes of resolution of peri‐implantitis lesions than the citric acid regimen. Conclusions: It is concluded that decontamination procedures including citric acid gel or rotating titanium brush did not improve outcomes following surgical treatment of experimental peri‐implantitis. Results were, however, influenced by the implant surface characteristics. [ABSTRACT FROM AUTHOR]

The objective of this in vitro study was to evaluate surface cleanness and cytocompatibility following mechanical instrumentation of biofilm‐contaminated titanium surfaces. Titanium discs (non‐modified [Ti(s)] and shot‐blasted surfaces [Ti(r)]) contaminated with Streptococcus gordonii were instrumented using four different techniques: (i) gauze soaked in saline (GS), (ii) ultra‐sonic device (US), (iii) rotating nickel‐titanium brush (TiB), or (iv) air‐polishing device (AP). Non‐contaminated, untreated titanium disks were used as controls (C). Residual deposits and cytocompatibility for osteoblast‐like cells were evaluated using scanning electron microscopy, immunofluorescence, and reverse transcriptase polymerase chain reaction. While the number of residual bacteria on Ti(s) discs was close to 0 in all treatment groups, significantly higher mean numbers of residual bacteria were observed on Ti(r) discs for GS (152.7 ± 75.7) and TiB (33.5 ± 22.2) than for US (0) and AP (0). Instrumentation with US resulted in deposition of foreign material (mean area% of foreign material: 3.0 ± 3.6% and 10.8 ± 9.6% for Ti(s) and Ti(r) discs, respectively). AP was the most effective decontamination procedure in reducing bacteria without depositing residual foreign material on Ti(r) discs. TiB and AP were superior methods in restoring cytocompatibility, although no method of mechanical decontamination resulted in pristine levels of cytocompatibility. [ABSTRACT FROM AUTHOR]

The aim of the present systematic review was to analyse studies using inorganic implant coatings and, in a meta‐analysis, the effect of specifically tricalcium phosphate (TCP) and hydroxyapatite (HA) implant surface coatings on bone formation according to the PRISMA criteria. Inclusion criteria were the comparison to rough surfaced titanium implants in large animal studies at different time points of healing. Forty studies met the inclusion criteria for the systematic review. Fifteen of these analyzed the bone‐to‐implant contact (BIC) around the most investigated inorganic titanium implant coatings, namely TCP and HA, and were included in the meta‐analysis. The results of the TCP group show after 14 days a BIC being 3.48% points lower compared with the reference surface. This difference in BIC decreases to 0.85% points after 21–28 days. After 42–84 days, the difference in BIC of 13.79% points is in favor of the TCP‐coatings. However, the results are not statistically significant, in part due to the fact that the variability between the studies increased over time. The results of the HA group show a significant difference in mean BIC of 6.94% points after 14 days in favor of the reference surface. After 21–28 days and 42–84 days the difference in BIC is slightly in favor of the test group with 1.53% points and 1.57% points, respectively, lacking significance. In large animals, there does not seem to be much effect of TCP‐coated or HA‐coated implants over uncoated rough titanium implants in the short term. [ABSTRACT FROM AUTHOR]

Objectives: To answer the focused question, 'In animals or patients with dental implants, does implant surface characteristics and/or implant material have an effect on incidence and progression of peri‐implantitis?' Material and Methods: Pre‐clinical in vivo experiments on experimental peri‐implantitis and clinical trials with any aim and design, and ≥5 years follow‐up, where the effect of ≥2 different type of implant material and/or surface characteristics on peri‐implantitis incidence or severity, and/or progression, implant survival or losses due to peri‐implantitis, and/or marginal bone levels/loss was assessed. Results: Meta‐analyses based on data of pre‐clinical experiments, using the ligature induced peri‐implantitis model in the dog, indicated that after the spontaneous progression phase implants with a modified surface showed significantly greater radiographic bone loss (effect size 0.44 mm; 95%CI 0.10–0.79; p =.012; 8 publications) and area of infiltrated connective tissue (effect size 0.75 mm2; 95%CI 0.15–1.34; p =.014; 5 publications) compared to non‐modified surfaces. However, in 9 out of the 18 included experiments, reported in 25 publications, no significant differences were shown among the different implant surface types assessed. Clinical and/or radiographic data from 7605 patients with 26,188 implants, reported in 31 publications (20 RCTs, 3 CTs, 4 prospective cohort, and 4 retrospective studies; 12 with follow‐up ≥10 years), overall did not show significant differences in the incidence of peri‐implantitis, when this was reported or could be inferred, among the various implant surfaces. In general, high survival rates (90–100%) up to 30 years and no clinically relevant differences in marginal bone loss/levels, merely compatible with crestal remodelling, were presented for the various implant types. Conclusion: Pre‐clinical in vivo experiments indicate that surface characteristics of modified implants may have a significant negative impact on peri‐implantitis progression, while clinical studies do not support the notion that there is a difference in peri‐implantitis incidence among the various types of implant surfaces. No assumptions can be made regarding the possible impact of implant material on incidence and/or peri‐implantitis progression due to limited information. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this experimental in vivo investigation was to evaluate the influence of modifying the implant surface by adding a monolayer of multi‐phosphonate molecules on the de novo bone formation and osseointegration. Material and Methods: The study was designed as an animal preclinical trial with intra‐animal control and two healing periods, 2 and 8 weeks, to compare implants with an identical macro‐design but with two different surfaces. Eight female Beagle dogs participated in the study. Control implants had a moderately rough surface combining sandblasting and acid etching; test implants had an additional monophosphonate layer covalently bonded to titanium. Histologic and radiographic (micro‐CT) outcome variables were evaluated. Results: The first bone‐to‐implant contact (fBIC) was located more coronally for the test implants at the first (0.065 mm (95% CI = −0.82, 0.60)) and second healing milestones (0.17 mm (95% CI = −0.9, 0.55)). Most coronal BIC of the test implants displayed a higher percentage of osseointegration, +6.33% and +13.38% after 2 and 8 weeks, respectively; however, the differences were not statistically significant. The micro‐CT examination did not show any BIC difference. Conclusions: The monophosphonate layer coating demonstrated clinical, histological, and radiographic results similar to the control surface. [ABSTRACT FROM AUTHOR]

Background: Although 5‐year clinical data exist for different zirconia implants, no analysis has yet been performed focusing on how the surface topography of the implant affects clinical parameters. Purpose: To analyze the influence of zirconia implant topography on first bone implant contact (fBIC). Materials and Methods: In a prospective two‐center cohort investigation 63 zirconia implants were evaluated at implant placement, prosthetic delivery, 1, 3, and 5 years. The distance (DIB) between implant shoulder and fBIC was measured at each time point in periapical radiographs at mesial and distal sites. Two‐way ANOVA/Bonferroni was used to analyze the effects of time and center (α < 0.05). Results: Between the centers, the mean DIB varied significantly at implant placement (Freiburg [FR]: 1.4 ± 0.6 mm; Zurich [ZH]: 0.8 ± 0.5 mm). Thereafter, no statistically significant difference in DIB was observed, neither between centers nor between time points (prosthetic delivery: FR: 1.9 ± 0.6 mm, ZH: 1.7 ± 0.8 mm; 1 year: FR: 1.8 ± 0.6 mm, ZH: 1.6 ± 0.8 mm; 3 years: FR: 1.9 ± 0.8 mm, ZH: 1.7 ± 0.8 mm; 5 years: FR: 1.9 ± 0.8 mm, ZH 1.8 ± 0.6 mm). The overall mean DIB at prosthetic delivery to 5 years of both centers (1.8 ± 0.7 mm) is located within the transition zone between the smooth neck and the moderately rough intraosseous part (1.6–2.0 mm from the implant shoulder). However, individual DIB values are ranging from 0.1 to 4.2 mm overlapping the transition zone. Conclusions: The standard deviation of the DIB indicates that the fBIC establishes on moderately rough and smooth surfaces. Consequently, soft tissue adapts to both topographies as well. [ABSTRACT FROM AUTHOR]

Objectives: To compare the marginal bone level around implants with a thin multi‐phosphonate coated surface after either an early or conventional loading protocol. Material and methods: A randomized pilot clinical trial was conducted. Dental impressions were obtained after either 4 (test) or 8 weeks (control) and single crowns screwed‐in 2 weeks later. Several variables were evaluated including radiographical marginal bone level (MBL), patient's level variables, and those related to the restoration and surrounding tissues. These data were obtained at several time points up to a 1‐year follow‐up. Results: Thirty‐four patients were included in the study, 18 assigned to the test group. No differences at implant placement were detected for tissue thickness, keratinized mucosa, nor any other clinical or radiological variable. At the time of impressions, tissue was thinner in the test group (2.30 (0.46) versus 2.78 (0.66) mm, test versus control, respectively; p =.012) so shorter abutments were used in this group. Regardless, no significant changes in marginal bone level were detected neither within group along time nor between groups. The average MBL at the 1‐year follow‐up was −0.15 (0.32) versus −0.22 (0.37) (p =.443) (test versus control, respectively). None of the clinical or radiological variables evaluated had a determinant influence on the MBL at any visit nor group. Conclusion: The use of implants with a multi‐phosphonate coated surface for early loading offers successful radiographical outcomes 1 year after loading. MBL over time was not affected by taking the impressions 4 or 8 weeks after implant placement and loading them 2 weeks later. [ABSTRACT FROM AUTHOR]

Objective: Mechanical plaque removal may alter the surface morphology of the gingival penetration part of the implant. We applied an air‐powered abrasive system (AP), titanium curette (TC), stainless curette (SC), ultrasound scaler (US), and titanium brush (TB) which are commonly used to remove plaque, to titanium or zirconia and the changes in surface morphology and the epithelial attach against substrata. Materials and Methods: (a) The morphological changes of titanium and zirconia after mechanical cleaning were assessed by scanning electron microscopy and a roughness analyser. (b) Oral epithelial cells of rats were inoculated on the surface of the materials after mechanical cleaning, and the adherence of epithelial cells was observed. (c) The maxillary first molars were extracted from the rats and replaced by experimental titanium or zirconia implants. The length of the immunoreactive laminin‐332 band was observed at the implant‐peri‐implant epithelium interface. Results: (a) The surface roughness increased in experimental groups except the AP group. (b) Among the experimental groups, the AP group showed the highest number of attached cells. (c) The length of the immunoreactive laminin‐332 band was longer in the control group than those in all five experimental groups. Among the experimental groups, the AP group showed the longest band. Conclusion: All mechanical cleaning methods increased the surface roughness of the materials except AP. AP did not cause distinct implant surface alterations. Surface alteration caused by mechanical cleaning may evoke inferior for epithelial attachment and reduce resistance against foreign infiltration. [ABSTRACT FROM AUTHOR]

Objective: To examine the progression of experimental peri‐implantitis around different implants placed in augmented and pristine sites. Materials and Methods: Six labrador dogs were used. Three months after tooth extraction, four implants with different surface modifications were installed on each side of the mandible. A standard osteotomy was applied on one side, while on the contralateral side the osteotomy was modified, resulting in a gap between the implant and the bone wall. The gap was filled with a bone substitute and covered by a resorbable membrane. Three months after implant installation, implants were exposed and healing abutments were connected. Two months later, oral hygiene procedures were abandoned and a cotton ligature was placed in a submarginal position around the neck of all implants and kept in place for 4 weeks. Following ligature removal, plaque formation continued for 6 months (spontaneous progression period). Radiographs were obtained throughout the experiment, and biopsies were collected and prepared for histological evaluation at the end of the spontaneous progression period. Results: Differences in bone loss during the spontaneous progression period between pristine and augmented sites were small. The size and vertical dimension of the peri‐implantitis lesion were larger at augmented than at pristine sites. Implants with non‐modified surfaces exhibited smaller amounts of bone loss and smaller dimensions of peri‐implantitis lesions than implants with modified surfaces. Conclusion: Small differences in spontaneous progression of peri‐implantitis were detected between pristine and augmented sites. Implants with modified surfaces exhibited more bone loss and larger lesions than implants with non‐modified surfaces, irrespective of the type of surrounding bone. [ABSTRACT FROM AUTHOR]

Background: In the past few decades, very little research has been carried out to modify implant surfaces to improve osteointegration through the regulation of immune cells. Purpose: The aim of this study is to investigate whether the poly(dopamine) (pDA)‐assisted immobilization of IL4 on titanium surfaces could modulate the inflammatory profile of macrophages in vitro and search for the possibility of enhancing implant integration in this way. Material and Methods: The surface composition, topography, and roughness of SLA, SLA‐pDA, and SLA‐pDA‐IL4 discs were examined by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Then the releasing profile of the SLA‐pDA‐IL4 implants was recorded for 1 week and the bioactivity of released IL4 was investigated by ELISA. Then macrophage polarization was investigated via three methods including: (a) surface marker via immunofluorescence; (b) mRNA levels of M1 and M2 polarization markers via real‐time PCR, and (c) cytokine release via ELISA. Results: SEM and EDS revealed that pDA and IL4 were coated successfully on SLA surfaces. The ELISA results showed that IL4 remained its bioactivity on SLA surface and were immobilized on the SLA surface. The immobilization of IL4 through pDA has no significant influence on the attachment, morphology, and proliferation of macrophages, while it increased the M2/M1 proportion in human macrophages revealed by immunofluorescence. The real‐time PCR and ELISA results demonstrated that SLA‐pDA‐IL4 surface reduced the pro‐inflammatory profile compared with SLA‐pDA and SLA surfaces. Conclusions: The SLA‐pDA‐IL4 surfaces described here is able to activate adherent macrophages into M2 phenotype and reduce the release of pro‐inflammatory cytokines. Immobilization of IL4 via pDA is convenient and effective, thus providing an applicable way to control macrophage behavior upon implant insertion and is anticipated to accelerating further bone integration. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of bone substitute materials on hard and soft tissue healing in reconstructive surgical therapy of experimental peri‐implantitis at implants with different surface characteristics. Material and methods: Six female, Labrador dogs were used. 3 months after tooth extraction, four implants with two different surface characteristics (A and B) were installed on each side of the mandible. Experimental peri‐implantitis was induced 3 months later. During surgical treatment of peri‐implantitis, the implants were cleaned with curettes and cotton pellets soaked in saline. The implant sites were allocated to one of four treatment categories; (a) Group C; no augmentation, (b) Group T1; bone defect filled with deproteinized bovine bone mineral (c) Group T2; bone defect filled with a biphasic bone graft material, (d) Group T3; bone defect filled as T1 and covered with a collagen membrane. Clinical and radiological examinations were performed, and biopsies were obtained and prepared for histological analysis 6 months after peri‐implantitis surgery. Results: Implant B (smooth surface) sites showed significantly (a) larger radiographic bone level gain, (b) enhanced resolution of peri‐implantitis lesions, and (c) larger frequency of re‐osseointegration than implant A (moderately rough surface) sites. Implant B sites also showed superior preservation of the mucosal margin. Differences between bone substitute materials and control procedures were overall small with limited advantages for T1 and T2 sites. Conclusion: Healing following reconstructive surgical treatment of experimental peri‐implantitis was superior around implants with a smooth surface than implants with a moderately rough surface. Benefits of using bone substitute materials during surgical therapy were overall small. [ABSTRACT FROM AUTHOR]

Background: The chemical surface structure of the porous titanium grafts has not been found to study in the literature on the similarity of chemical surfaces of different commercial dental implants. Purpose: The purpose of this study is to investigate the chemical composition and surface energies of white (WPTG) and black porous titanium granules (PTG) by energy dispersive x‐ray spectrometry (EDX) analysis to compare with different commercial dental implant surface. Materials and Methods: The surface chemical compositions of six commercially available dental implants with different surface structures, PTG and WPTG were examined by EDX analysis. Surface analyzes were performed on the apical, middle, and coronal parts of each implant and on the top, flank, and valley regions on each side. Surface analyzes of dental implants were evaluated at ×200 and ×2000 magnifications. The EDX evaluation of PTG grafts were evaluated at ×250, ×2000, ×5000, and ×50 000 magnifications. Results: PTG grafts showed elements of Na (8.88 ± 9.98%), Cl (2.44 ± 1.96%), and Al (0.99 ± 0.37%) as well as Ti (90.06 ± 11.34%) molecule at ×5000 magnification. In WPTG, Ti (%34.55 ± 6.41%) and O (%65.44 ± 6.42%) molecules were detected. Conclusions: It has been found that PTG surface was not made of pure titanium, it has different chemical molecules at larger magnifications. Cell culture and experimental studies are needed to establish a relationship between the different commercial implants and the surface structure of the titanium granules. [ABSTRACT FROM AUTHOR]

Background: Poor osseointegration of dental implants often occurs in osteoporotic patients and processed implant surfaces could help to improve the dilemma. Purpose: This study aimed to compare the effects of different titanium (Ti) surfaces on bone‐implant osseointegration in ovariectomized (OVX) sheep. Materials and Methods: Four groups were included: smooth titanium (ST) was merely polished Ti; micro titanium (MT) was treated with hydrofluoric acid (HF) for 30 minutes; strontium‐loaded nano titanium (NT‐Sr) was formed by magnetron sputtering; strontium‐loaded micro/nano titanium (MNT‐Sr) was fabricated by HF etching combined with magnetron sputtering. The biological responses were evaluated by human bone marrow‐derived mesenchymal stem cells (hBMMSCs) experiments in vitro. Osseointegration was evaluated in vivo after each surface implant was inserted into OVX sheep' mandibles. Results: The numbers of adhered and mineralized hBMMSCs increased significantly in the MNT‐Sr group. The bone‐implant contact and the maximal pull‐out force increased significantly with MNT‐Sr surface. The bone volume ratio and trabecular number of the MNT‐Sr group were significantly higher than others, whereas trabecular separation decreased. Conclusions: These results indicated that an MNT‐Sr surface promotes the differentiation of hBMMSCs in vitro and enhances bone‐implant osseointegration in vivo, which may be a promising option for clinical implants in osteoporotic patients. [ABSTRACT FROM AUTHOR]

Background: The understanding of mechanisms of osseointegration as well as applied knowledge about oral implant surfaces are of paramount importance for successful clinical results. Purpose: The aim of the present article is to present an overview of osseointegration mechanisms and an introduction to surface innovations with relevance for osseointegration that will be published in the same supplement of Clinical Implant Dentistry and Related Research. Materials and Methods: The present article is a narrative review of some osseointegration and implant surface‐related details. Results and Conclusions: Osseointegration has a changed definition since it is realized today that oral implants are but foreign bodies and that this fact explains osseointegration as a protection mechanism of the tissues. Given adequate stability, bone tissue is formed around titanium implants to shield them from the tissues. Oral implant surfaces may be characterized by microroughness and nanoroughness, by surface chemical composition and by physical and mechanical parameters. An isotropic, moderately rough implant surface such as seen on the TiUnite device has displayed improved clinical results compared to previously used minimally rough or rough surfaces. However, there is a lack of clinical evidence supporting any particular type of nanoroughness pattern that, at best, is documented with results from animal studies. It is possible, but as yet unproven, that clinical results may be supported by a certain chemical composition of the implant surface. The same can be said with respect to hydrophilicity of implant surfaces; positive animal data may suggest some promise, but there is a lack of clinical evidence that hydrophilic implants result in improved clinical outcome of more hydrophobic surfaces. With respect to mechanical properties, it seems obvious that those must be encompassing the loading of oral implants, but we need more research on the mechanically ideal implant surface from a clinical aspect. [ABSTRACT FROM AUTHOR]

Purpose: To study the incidence of early implant failures in edentulous jaws and to describe the effects of some patient‐ and implant‐related factors on the risk for early implant failures. Materials and Methods: The study retrospectively analyzed 4615 edentulous jaws (4067 patients), consecutively treated with dental implants at one referral clinic from 1986 to 2013. Implant failures that occurred from implant surgery up to the first recall examination 1 year after prosthesis insertion were recorded and defined as early implant failures. All removed implants were included as failures. Features of the study group and early implant failure rates were reported. A multivariable logistic regression model was used for analyzing possible associations between clinical factors, and the risk for early implant failures. Implant surfaces were categorized by means of roughness: turned (Sa 0.5‐1.0 μm) and moderately rough (Sa 1.0‐2.0 μm). Results: Three hundred twenty‐seven patients (344 jaws) were lost to follow‐up. Early implant failures occurred in 8.6% of the jaws. In the maxilla there was a significantly higher incidence of early failures compared to the mandible both with turned implants, OR 5.93 (95% CI 4.21; 8.36), and moderately rough implants, OR 2.52 (95% CI 1.19; 5.34). The impact of implant surface roughness was significant in the maxilla with higher incidence of early failures with turned implants, OR 3.51 (95% CI 2.27; 5.42). There was a significant interaction between implant surface and jaw type on early failures (p = 0.034). Older age was associated with lower risk for early implant failures, OR 0.9 (95%CI 0.82; 0.99). In total, 63% of the jaws with failure could proceed with the prosthetic treatment without further implant insertions. Twenty‐six percent of the early failures occurred after prosthesis insertion and 59% of those could maintain the same prosthesis after implant loss with or without adjustments. Conclusions: Changing the implant surface from turned to moderately rough decreased the incidence of early implant failures significantly in the maxilla, but not in the mandible. Older age at implant insertion was associated with lower risk for early implant failures in edentulous patients. [ABSTRACT FROM AUTHOR]

Survival, differentiation capability, and activity of cells are strictly related to structural features and the composition of the extracellular matrix, and its variation affects tissue homeostasis. Placement of a dental implant in bone tissue activates a sequence of molecular and cellular events that lead to the apposition of newly-formed bone directly onto the titanium surface. Due to implant's interaction with the mineralized tissue, osseointegration is affected by the surface structure of the implanted material. Surface nanotopography and microtopography can modify the shape and activity of mesenchymal stem cells leading to a higher differentiation rate of these cells into osteogenic lineage with the upregulation of osteoblastic genes. Several approaches for implant surface modification are currently under investigation or have been recently proposed to improve osseointegration. Most surface treatments are aimed at the formation of a thick layer of titanium oxide, at the alteration of surface chemical composition by incorporating bioactive molecules and drugs, and at the creation of a surface topography that is more attractive for osteoblast differentiation, adhesion, and osteogenic activity. Data on the cellular-substrate interaction, as well as in vivo studies assessing the response to these novel surfaces, are reviewed in the present study. The application of modern surfaces in dental clinical practice might increase and accelerate implant osseointegration, but could also reduce the occurrence of peri-implant bone loss and favor the re-osseointegration of an affected surface. [ABSTRACT FROM AUTHOR]

Purpose The aim of current split‐mouth study is to compare crestal bone loss of hybrid with moderately rough implants in patients with a bar‐supported mandibular overdenture. Materials and Methods: Fully edentulous patients were enrolled for treatment with implant‐supported overdentures. Each patient received two implants of which one moderately rough (Sa: 1.3 μm) and one hybrid surface implant (moderately rough implant body [Sa: 1.3 μm] and a minimally rough implant neck [Sa: 0.9 μm]). Beside the difference in implant surface the two implants are identical. After 3 and 12 months, peri‐apical radiographs were taken to assess crestal bone levels and a Wilcoxon signed‐rank test was used for pairwise comparison. Results: Forty‐two implants were placed in 21 patients and no failures occurred after 1 year. An overall mean crestal bone loss of 0.40 mm (SD: 0.76; range: 0‐3.93) and 0.35 mm (SD: 0.59; range: 0‐2.56) was registered after a mean follow‐up of 3.4 and 15.8 months. There was no statistical significant difference in crestal bone loss between the different implant surfaces or between the different time intervals. Conclusion: From this randomized controlled trial, it can be concluded that hybrid surface implants may be a viable alternative for implant treatment in the edentulous mandible. [ABSTRACT FROM AUTHOR]

Objective: This study assessed the bone formation around titanium surface incorporating the calcium–magnesium (CaMg) deposited by blasted in rabbit tibia bone to determine whether this surface would further enhance bone healing compared with commercially available implant surface. Material and methods: The deposition of CaMg on the titanium SLA surface were obtained by blasting formed the experimental group (EX group), while implants with traditional SLA surface were used as control group (CO group), in this study. Fifty cylindrical threaded implants with a length of 8 mm were used (P = 25 per group). Five implants of each group were used to surface characterization by scanning electron microscopy, energy dispersive spectrometry, and optical profilometry. Ten New Zealand white rabbits received 40 implants (n = 20 per group). Resonance frequency analysis was performed three times (0, 4, and 6 weeks). Histomorphometric analysis was performed 4 and 6 weeks after implantation. Statistical significance was set at P < 0.05. Results: Blasted CaMg deposition on SLA implant surface displayed almost identical surface morphologies and R(a) values at the micron scale. In comparing the implant stability quotient at the three time points, highly significant statistic differences were found (P < 0.001). Histomorphological analysis showed higher degrees of bone organization in the samples of test implant surfaces at both implantation times. Conclusion: Within the limitations of this study, the results indicate that the deposition of CaMg on the SLA titanium surface may be effective in enhancing the osseointegration of moderately rough grit‐blasted implants by increasing the degree of bone–implant contact. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To evaluate the effect of soft tissue thickness on bone remodelling and to investigate whether implant surface exposure can be avoided by adapting the vertical implant position in relation to the soft tissue thickness. Materials and Methods: Twenty‐five patients received two non‐splinted implants supporting an overdenture in the mandible. Soft tissue thickness was measured using bone sounding and ultrasonically. One implant was installed equicrestally (control), and the vertical position of the second implant was adapted to the site‐specific soft tissue thickness (test). Crestal bone levels were determined on digital peri‐apical radiographs and compared with baseline (implant placement). Results: Twenty‐five patients were consecutively treated. No implants failed during the follow‐up. A significant correlation was observed between soft tissue thickness and bone level alterations after 6 months (ultrasound ICC = 0.610; bone sounding ICC = 0.641) with inferior bone levels for equicrestal implants when thin tissues are present. Subcrestal implants showed significantly better bone levels after 6‐month (n = 24, 0.04 mm versus 0.72 mm; p < .001), 1‐year (n = 24, 0.03 mm versus 0.77 mm; p < .001) and 2‐year follow‐up (n = 24, 0.04 mm versus 0.73 mm; p < .001). Conclusion: Initial bone remodelling was affected by soft tissue thickness. Anticipating biologic width re‐establishment by adapting the vertical position of the implant seemed highly successful to avoid implant surface exposure. [ABSTRACT FROM AUTHOR]

Implant integration is a complex process mediated by the interaction of the implant surface with the surrounding ions, proteins, bacteria, and tissue cells. Although most implants achieve long-term bone-tissue integration, preventing pervasive implant-centered infections demands further advances, particularly in surfaces design. In this work, we analyzed classical microrough implant surfaces (only acid etched, AE; sandblasted then acid etching, SB + AE) and a new calcium-ion-modified implant surface (AE + Ca) in terms of soft- and hard-tissue integration, bacterial adhesion, and biofilm formation. We cultured on the surfaces primary oral cells from gingiva and alveolar bone, and three representative bacterial strains of the oral cavity, emulating oral conditions of natural saliva and blood plasma. With respect to gingiva and bone cells and in the presence of platelets and plasma proteins, AE + Ca surfaces yielded in average 86% higher adhesion, 44% more proliferation, and triggered 246% more synthesis of extracellular matrix biomolecules than AE-unmodified controls. Concomitantly, AE + Ca surfaces regardless of conditioning with saliva and/or blood plasma showed significantly less bacterial adhesion (67% reduction in average) and biofilm formation (40% reduction in average) than unmodified surfaces. These results highlight the importance of a calcium-rich hydrated interface to favor mammalian cell functions over microbial colonization at implant surfaces. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 421-432, 2018. [ABSTRACT FROM AUTHOR]

The combination of increased healthcare access, universal aging, and infallible therapy demands, synergistically drive the need for the development of biomaterial technologies that mitigate the challenge of biomaterial-associated infections (BAI). Staphylococcus epidermidis and Staphylococcus aureus account for the majority of BAI due to their ability to accumulate in adherent multilayered biofilm. This investigation details the development of gene expression assays to evaluate the genetic processes of attachment, accumulation, maturation, and dispersal phases of biofilms on biomaterials in vitro, while abiding by the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines. The biofilm formation of S. epidermidis on polyurethane (PU) central venous catheters and S. aureus on machined titanium (Ti) was examined in terms of gene expression at early and late time points. The results provided insight into how each stage of biofilm formation is orchestrated over time on these biomaterials in vitro. Furthermore, the results suggested that mechanical RNA extraction, organic solvents, elimination of genomic DNA, and preamplification are advisable strategies to implement for biofilm gene expression analysis. It is concluded that this method can be employed for the assessment of biofilm-biomaterial interactions at the molecular level. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3400-3412, 2017. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to perform a histomorphometric evaluation of the healing characteristics and jawbone remodeling processes in the peri-implant bone tissue of three commonly used implant surfaces, during the early weeks of osseointegration. Material and methods Dental implants with three different surfaces (anodically modified, hydroxyapatite ( HA)-coated and machined) were inserted into the mandibular side-tooth region of twelve adult mini-pigs. Histomorphometric analyses were performed to evaluate remodeling processes 3, 6 and 12 weeks post-implantation. Results Only a few very early bone remodeling-resorption sites were found at 3 weeks. After 6 weeks, additional signs of remodeling-related reversal and bone formation were detectable in all three groups, which steadily increased until 12 weeks. At the latter time point, the amount of remodeled bone was significantly higher for the anodized and HA-coated surfaces than for the machined implants. Conclusion The results of this study demonstrate that peri-implant bone remodeling can start as early as 3 weeks after implantation and continues at a substantial level up to 12 weeks. The anodic modification or HA coating of implant surfaces appears to accelerate the conversion of primary regenerated bone into more mature secondary lamellar bone. If this observation is of clinical relevance, it has to be clarified in studies that include longer observational time periods. [ABSTRACT FROM AUTHOR]

Objectives To compare the peri-implant bone healing between TiZr implants with hydrophilic SLActive and hydrophobic SLA implant surface in patients receiving anticoagulants, to assess the implant survival and success rate, as well as to evaluate whether small-diameter TiZr implants could be used in patients on OAT in order to avoid augmentation procedures. Material and methods A total of 80 small-diameter tissue-level TiZr implants with SLActive and SLA surfaces were placed in 20 anticoagulated patients, following the 'split-mouth' study design. Implant stability was measured up to the third postoperative month by resonance frequency measurements ( RFA). One-year implant survival and success rate were evaluated. Results After one year, 100% implant survival and success rate were observed. A significant decrease in ISQ comparing to baseline values was noted in the SLActive group from the first postoperative week, and in the SLA group, from the 3rd week after the surgery. In both groups, a statistically significant decline in ISQ was observed between second and third postoperative week. No significant differences in ISQ values between SLActive and SLA implants were noted, at any time point. Conclusions Titanium-zirconium small-diameter implants with SLActive and SLA surface predictably achieve and maintain adequate bone tissue integration in patients receiving anticoagulants. OAT appears to influence the bone healing events resulting in lower ISQ in the end of 3-month period in comparison with baseline values, although without compromising implant stability. [ABSTRACT FROM AUTHOR]

Background Chemical modifications of the dental implant surface that improve the wettability result in a faster and better osseointegration. Purpose The aim of this randomized clinical trial was to evaluate the implant stability quotient (ISQ) of implants with similar designs, treated with 2 surfaces, sandblasted acid-etched (SAE) and hydrophilic SAE, within the initial 16 weeks of healing. Material and methods A total of 64 implants (32 SAE-control group and 32 modified SAE-test group) with the same design, length, and diameter (conical and compressive, 4.3 × 10 mm) were inserted into the posterior maxillae of 21 patients partially edentulous. The ISQ values were collected at post-surgery (T0), 1 week (T1), 2 weeks (T2), 3 weeks (T3), 5 weeks (T4), 8 weeks (T5), 12 weeks (T6), and 16 weeks (T7). Results None of the implants failed. Test group presented ISQ values higher than the control group (ANOVA- P < .01) from T5 to T7. When comparing groups regarding the amount of time required to achieve ISQ ≥ 70 as a reference, there was a statistically significant difference (cox regression- P < .01), and a hazard ratio of 2.24 (CI 1.62-3.11). At the 1-year follow-up, there was a drop out of 1 patient, and 2 implants were no longer evaluated. Survival rate for both groups was 100% at the 1-year follow-up. Conclusions The current study suggests that implants with hydrophilic surface (modified SAE) integrate faster than implants with SAE surface. The stability gain of the test group was 2.24 times faster than the control group after 5 weeks of evaluation at the posterior region of the edentulous maxillae. [ABSTRACT FROM AUTHOR]

Background The mechanisms behind the impact of smoking on osseointegration are not fully understood. Purpose To investigate the initial clinical and molecular course of osseointegration of different implants in smokers and non-smokers in a randomized controlled trial (RCT). Materials and Methods Smoking ( n = 16) and non-smoking ( n = 16) patients received 3 implant types: machined, oxidized, and laser-modified surfaces. Baseline bone biopsies were retrieved from the implant sites. After 60 and 90 days, the pain score, implant stability quotient (ISQ), and peri-implant crevicular fluid (PICF) gene expression were analyzed. Furthermore, radiological and clinical assessments were made at 90 days. Results At 90 days, no pain was reported, irrespective of smoking habit. A higher ISQ was found in smokers compared with non-smokers. Marginal bone loss (MBL) was greater in smokers than in non-smokers. The comparison of implant surfaces revealed greater MBL exclusively at the machined implants in smokers. At 90 days in smokers, the PICF around machined implants revealed a higher expression of the proinflammatory cytokine, interleukin-6 (IL-6), and a lower expression of the osteogenic gene, osteocalcin (OC), compared with the PICF around modified implants. Furthermore, OC expression was lower at machined implants in smokers compared with machined implants in non-smokers. After adjustment for age and implant location (maxilla/mandible), multivariate regression revealed the following predictors of MBL: smoking, bleeding on probing at 90 days, hypoxia-inducible factor 1 alpha (HIF-1α) expression at baseline and IL-6 expression in PICF at 90 days. Conclusions During the early phase of osseointegration, non-smokers and smokers present a similar, high implant survival. In contrast, smokers present a greater MBL, particularly at machined implants. HIF-1α baseline expression in the recipient bone and IL-6 expression in PICF cells are important molecular determinants for MBL after 90 days. It is concluded that smoking has an early effect on osseointegration, which is dependent on the implant surface properties and the local host response. [ABSTRACT FROM AUTHOR]

Aim To study sequential osseointegration around implants with nano-technologically modified surfaces at different periods of healing. Materials and methods After 3 months, two different implant systems with different nano-technologically modified surfaces were randomly installed in the edentulous molar regions of the mandible of 12 dogs. One surface was acid-etched surface, and subsequently modified with calcium ions (UnicCa®), while the other was a hydrophilic sandblasted with large grit and acid-etched ( SLActive®) surface. The implants were fully submerged, and biopsies were obtained representing the healing after 1, 2, 4 and 8 weeks ( n = 6 per period). A morphometric evaluation of densities of new soft tissues (provisional matrix and immature bone marrow), new and old bone, mature bone marrow, vessels and other tissues (bone debris/particles and clot) was performed in the spongiosa compartment of the sites of implantation. Results After 1 week of healing, the soft tissues, mainly composed of provisional matrix, were present at 41.5 ± 23.9% and 30.1 ± 20.0% at the UnicCa® and SLActive surfaces, respectively. These percentages were >40% at both surfaces after 2 weeks of healing, presenting greater amount of immature bone marrow. Subsequently, these percentages decreased up to disappear after 8 weeks of healing. New bone increased progressively between 1 and 8 weeks of healing from 8.2 ± 3.0% to 77.1 ± 6.4% and from 6.8 ± 2.8% to 67.9 ± 6.8% at the UnicCa® and SLActive®, respectively. Old bone decreased progressively over time. Conclusions The patterns of healing at highly hydrophilic surfaces occurred through the early formation of a provisional matrix followed by the formation of new bone and marrow at various stages of maturation. The healing was similar to those described in different animal models, anatomical sites and surgical procedures. [ABSTRACT FROM AUTHOR]

Background Smoking is a risk factor for dental implants. The mechanisms behind the impact of smoking on osseointegration are not fully understood. Purpose To investigate the initial molecular and clinical course of osseointegration of different titanium implants in smokers and nonsmokers. Materials and Methods Smoker (n = 16) and nonsmoker (n = 16) patients were included. Each patient received three implant types: machined, oxidized and laser-modified surfaces. After 1, 7, 14, and 28 days, the peri-implant crevicular fluid (PICF) was sampled for gene expression analysis of selected factors involved in early processes of osseointegration. Furthermore, pain-score (VAS), resonance frequency analysis (RFA) and baseline clinical assessments were performed. Results Early failure of osseointegration, associated with a high and sustained perception of pain, was encountered in 3/32 patients. In general, high pain scores were reported during the first days after implantation, irrespective to smoking habit, which correlated to high levels of pro-inflammatory cytokines during the first days after implantation. Higher ISQ values were found in smokers compared to nonsmokers. In smokers exclusively, ISQ values correlated to harder and less atrophic bone quality and quantity, respectively. Smokers displayed a higher expression of osteocalcin (OC), but later peak and lower expression of bone morphogenetic protein (BMP-2) (at 7 days) compared to nonsmokers. In comparison to machined implants, surface-modified implants were associated with higher expression of alkaline phosphatase (ALP) and cathepsin K (CatK) at 28 days in nonsmokers. Conclusions During the early phase of osseointegration, postoperative pain is linked to the inflammatory cell response and, may tentatively serve as an indicator of biological complication and implant loss. The present study suggests that smokers have an altered bone composition and (ultra)structure based on the observations that ISQ values are higher and correlate to recipient bone quality and quantity in smokers. [ABSTRACT FROM AUTHOR]

Objective: To characterize the profile of microbial communities colonizing titanium implants with different surface treatments after exposure to the oral environment at the genus or higher taxonomic level. Material and methods: Sixteen titanium disks, machined or sandblasted large-grit and acid-etched (SLA), were mounted on removable intraoral splints worn by four patients. After 24 h of intraoral exposure, biofilm samples were collected from disks and supra/subgingival teeth areas. The 16S rDNA genes from each sample were amplified, sequenced with the Miseq Illumina instrument and analyzed. Results: A total of 29 genera and seven more inclusive taxa, representing the phyla Firmicutes, Proteobacteria, Fusobacteria, Bacteroidetes, Actinobacteria and candidate division TM7 were identified in both titanium surfaces and teeth. No differences were found in relation to the operational taxonomic units (OTUs) and microbial diversity, assessed by Chao 1 and Shannon indices, when comparing SLA and machined titanium surfaces. Conclusions: Machined and SLA surfaces are colonized by similar numbers of prokaryotic OTUs after 24 h of exposure to the oral environment. Higher complexity of the titanium surface topography in the initial phase of biofilm maturation does not seem to significantly influence the colonizing microbiota. Commercially, [ABSTRACT FROM AUTHOR]

Objectives The overall aim of the study was to investigate a biofunctionalized implant surface with electrochemically deposition of hydroxyapatite and the synthetic peptide (P-15) and its effect on osseointegration. Material and methods Three modified implant types of ANKYLOS® C/X implants were used; (1) machined implants used as negative control (M, n = 20), (2) implants with the FRIADENT® plus surface (grit blasted and acid-etched) used as positive control (P, n = 20), and (3) implants with a biomimetic surface consisting of hydroxyapatite and the synthetic 15 aminoacids containing peptide P-15 ( BP, n = 40). The implants were randomly inserted in the mandibles of 10 beagle dogs following 4 months after tooth extraction (P1-P4). Three animals were sacrificed 2 and 7 days after implant insertion, respectively, and four animals were sacrificed 6 months post implant insertion. Bone-to-implant contacts ( BICs) were analyzed via histomorphometrical analyses at five different region of interests ( ROIs); two at the middle part on either side of the implant ( ROI 1/4), two at the apical part of the implant at each side ( ROI 2/3), and one at the tip of the implant ( ROI 5). Results All implant surfaces showed a high level of osseointegration and osteoconductivity. The cumulative implant survival rate ( CSR) was 93.8%, 100% in the M, 85% in the P, and 95% in the BP group. No statistical difference in BICs at ROI 1/4, 2/3, and 5 could be shown between implant types following 2 and 7 days of healing. BIC values increased in all groups over time. After 6 months of healing the BP group showed superiority in BIC in ROI 2/3 (73.2 ± 15.6%) compared to the P (48.3 ± 10.6%) and M group (66.3 ± 30.2%) with a significant difference between BP and P ( P = 0.002). Conclusion It is hypothesized, that the surface biofunctionalization improves peri-implant bone formation and remodeling, leading to an increased bone-to implant contact. However, within the limitations of the study set-up no benefit in the early phase of osseointegration could be established for dental implants with P-15 containing surface in this study. [ABSTRACT FROM AUTHOR]

Background Compared with knowledge on patient and implant component factors, little knowledge is available on surgeons' role in early implant failures. Purpose To report incidence of early implant failures related to total number of operations performed by individual surgeons. Materials and Methods Early implant failures (≤1 year of implant prosthesis function) were reported after a total of 11,074 implant operations at one specialist clinic during 28 years of surgery. Altogether, 8,808 individual patients were treated by 23 different dentists, of whom 21 surgeons were specialists in oral surgery or periodontology. Recorded failures were related to total numbers of performed operations per surgeon, followed by statistical comparisons (χ2) between surgeons with regard to type of treated jaw and implant surface. Results Altogether, 616 operations were recorded with early implant failures (5.6%), most often observed in edentulous upper jaws after placing implants with a turned surface ( p < .05). Significant differences between surgeons, gender of surgeon, type of treated jaws by the surgeon, and implant surface used by the surgeon could be observed ( p < .05). Conclusions Early implant failures are complex, multifactorial problems associated with many aspects in the surgical procedure. A stochastic variation of failures for individual surgeons could be observed over the years. Different levels of failure rate could be observed between the surgeons, occasionally reaching significant levels as a total or for different jaw situations ( p < .05). The surgeons reduced their failure rates when using implants with moderately rough surfaces ( p < .5), but the relationship of failure rate between the surgeons was maintained. [ABSTRACT FROM AUTHOR]

Background There is a need for more studies investigating the outcome of implant-supported rehabilitations in patients with systemic disorders. Materials and Methods This retrospective clinical study included 721 patients with systemic disorders or smoking habits (422 females; 299 males), with an average age of 51 years, rehabilitated with 3,998 implants and followed for 3-17 years (average 8 years). Outcome measures were: implant survival rates calculated based on implant function through life tables and using the patient (first implant failure censored) and implant as units of analysis; marginal bone levels measured at 1, 5, and 10 years; and the incidence of biological complications (peri-implant pathology, abscess formation, fistula formation, and suppuration). Results Eighty-seven patients were lost to follow-up (12%). Forty-five patients experienced prosthetic failure rendering a 94.3% survival rate. One hundred seventy-three implants failed in 98 patients, rendering an 83.5% (patient level) and 94.6% (implant level) cumulative survival rate. The average marginal bone levels were 1.18 mm, 1.56 mm, and 1.47 mm at 1, 5, and 10 years, respectively. Biological complications occurred in 86 patients (11.9%). Conclusions Implant rehabilitations in patients presenting systemic disorders or smoking habits are possible with good outcomes. Nevertheless, different impacts on implant rehabilitations were registered according to the type of systemic disorder. [ABSTRACT FROM AUTHOR]

Background The discrepancy between some scientific views and the daily clinical experience with dental implants has made the topic of 'periimplantitis' highly controversial, especially the discussion whether 'periimplantitis' should even be considered a 'disease' or whether marginal bone loss instead would represent a complication of having a foreign body placed in the oral cavity. Purpose The aim of the present paper was to present the outcomes from a consensus meeting on 'peri-implantitis' in Rome, Italy (January 8-10, 2016). Materials and Methods Seventeen clinical scientists were invited to, based on prepared reviews of the literature, discuss topics related to 'periimplantitis.' Results and conclusions Oral implants may lose bone or even display clinical failure. However, progressive bone loss threatening implant survival is rare and limited to a percent or two of all implants followed up over 10 years or more, provided that controlled implant systems are being used by properly trained clinicians. There is very little evidence pointing to implants suffering from a defined disease entity entitled 'peri-implantitis.' Marginal bone loss around implants is in the great majority of cases associated with immune-osteolytic reactions. Complicating factors include patient genetic disorders, patient smoking, cement or impression material remnants in the peri-implant sulcus, bacterial contamination of the implant components and technical issues such as loose screws, mobile components or fractured materials. These reactions combine to result in cellular responses with the end result being a shift in the delicate balance between the osteoblast and the osteoclast resulting in bone resorption. However, the great majority of controlled implants display a foreign body equilibrium resulting in very high survival rates of the implants over long term of follow-up. [ABSTRACT FROM AUTHOR]

Aim: To evaluate in vitro topographical and composition changes by piezoelectric ultrasonic instrumentation with metallic and plastic tips on machined and moderately roughened titanium surfaces. Methods: Twenty machined and moderately roughened laser-marked titanium discs were ultrasonically instrumented with metallic and plastic tips. Surface instrumentation was carried out with controlled pressure for 20 and 30 seconds at two power settings. For each time and power setting, instrumentation was repeated four times with one instrumentation per disc quadrant. Surface topography analysis was performed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Surface roughness measurements were compared between instrumented and non-instrumented surfaces. Surface element composition and rinsing solutions were evaluated using energy-dispersive spectroscopy (EDS) and trace elemental analysis using inductively coupled plasma mass spectrometry (ICPMS), respectively. Results: SEM photomicrographs and CLSM 3D surface plot images of instrumented machined and moderately roughened surfaces demonstrated severe surface topographical alterations with metallic tips and mild to moderate changes for plastic tip instrumented sites. ICPMS analysis of the rinsing solutions identified titanium and other metal traces with the use of metallic tips, and mainly titanium and carbon when plastic tips were used. Surface EDS analysis showed elemental traces of the ultrasonic tips. Conclusion: Ultrasonic instrumentation with metallic or plastic tips created surface topographical and compositional changes. Different changes in surface topography were noted between the surfaces, as the roughness of the machined surfaces increased while the extent of roughness of the moderately roughened surfaces decreased. The clinical relevance of these changes is yet to be determined. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the peri-implant soft and hard tissue adaptation at implants with different modified surfaces and configurations. Materials and Methods Six Beagle dogs were used. Mandibular premolars and first molars were extracted bilaterally. After 3 months, full-thickness flaps were elevated, and two different types of trans-mucosal implants ( ICX- Gold®, Medentis Medical Gmb H, Dernau, Germany and SLActive®, Institute Straumann, Bern, Switzerland) and two different surfaces were randomly installed in the distal regions of one side of the mandible. Abutments were applied, and a nonsubmerged healing was allowed. After 1 month, the procedures were performed in the other side of the mandible, and after a further month, the animals were sacrificed, biopsies were collected, and ground sections prepared for histological examination. Results Similar results in marginal bone and soft tissues dimensions were observed after 1 month of healing at the two implant systems used, and no major changes could be observed after 2 months of healing. After 1 month, the percentage of new bone was 69.0% and 68.8% at ICX- Gold and SLActive surfaces, respectively. After 2 months, the percentage of new bone was 67.8% and 71.9% at ICX- Gold Medentis and SLActive surfaces, respectively. No statistically significant differences in osseointegration were found. Conclusion The two implant systems used resulted in similar osseointegration after 1 and 2 months of healing. [ABSTRACT FROM AUTHOR]

Aim To report on a possible relationship between the use of dental floss or superfloss and the development of peri-implantitis. Materials and methods Ten patients with progressive peri-implantitis with an intensive oral hygiene protocol, which consisted of extensive professional supra- and submucosal cleaning, and not responding to this therapy were scheduled for examination. Plaque and bleeding indices and probing depth measurements were assessed, and radiographic examination was performed every two years. Results In all ten cases, remnants of dental floss were found around the neck and coronal part of a dental implant. After careful removal of these floss remnants and implant cleansing, a significant improvement in the peri-implant conditions in nine of ten cases was noted. In one case, peri-implant probing depth decreased substantially. However, bleeding on probing was still present. In vitro testing yielded that the application of various types of dental floss on the exposed rough implant surfaces may easily lead to tearing of floss fibers. This may result in the deposition of floss remnants on rough implant surfaces, which, in turn, may lead to the development of plaque-related peri-implant inflammation and, subsequently, bone loss. Conclusion In case of exposed rough surfaces of the dental implant, the peri-implant conditions may be jeopardized by the application of dental floss, and hence, the utilization of interproximal brushes or toothpicks may be preferred for daily home care practices. [ABSTRACT FROM AUTHOR]

Purpose The aim of this paper was to study the sequential healing of bone tissues at implants with different configuration and different modified surfaces. Materials and Methods Twelve Beagle dogs were used. Extractions of all teeth from the second premolar to the first molar were performed in both sides of the mandible. After 3 months, full-thickness flaps were elevated and two implants of different systems and with different surfaces were randomly installed in the premolar region in one side of the mandible. One surface was acid etched and further modified with calcium ions ( BTI unicCa®), the other was sandblasted and acid etched plus a nanometer calcium phosphate deposition (3i T3®). The flaps were sutured to allow a fully submerged healing. The surgery on the other side of the mandible and the sacrifices were planned in such a way to obtain biopsies representing the healing after 1, 2, 4, and 8 weeks ( n = 6 per period). Results After 1 and 2 weeks of healing, the mean values of new bone apposition on the implant surfaces were 5.9 ± 3.3% and 29.8 ± 16.0% at BTI unicCa and 4.6 ± 3.3% and 12.4 ± 5.6% at 3i T3, respectively. After 4 and 8 weeks, the percentage increased, being 49.4 ± 8.1% and 63.6 ± 7.3% at BTI unicCa and 40.3 ± 10.0% and 47.3 ± 20.2 at 3i T3, respectively. Differences statistically significant between the two surfaces were found only at the 2- and 4-week observation periods. Concomitantly, the old bone was resorbed at both surfaces from about 15-17% after 1 week to about 4-6% after 8 weeks of healing. Conclusion Moderately rough surfaces modified with calcium ions or discrete calcium phosphate nanocrystalline deposition showed similar patterns of sequential healing. Higher new bone percentages were found at BTI unicCa compared with the 3i T3 implants, the difference being statistically significant at 2 and 4 weeks observation. [ABSTRACT FROM AUTHOR]

Aim To study the sequential events in osseointegration at implants with highly hydrophilic surfaces. Material and methods All premolars and the first molars were bilaterally extracted in 12 Beagle dogs. After 3 months, full-thickness flaps were elevated and two different implants systems with various surfaces were randomly installed in the edentulous premolar region in one side of the mandible. One surface was acid etched and further modified with calcium ions (UnicCa®), while the other was sandblasted with large grits and acid etched ( SLActive®). The flaps were sutured to allow a fully submerged healing. The surgery on the other side of the mandible and the sacrifices were planned in such a way to obtain biopsies representing the healing after 1, 2, 4, and 8 weeks ( n = 6 per period). Results After one week of healing, new bone apposition was found at both surfaces with percentages of 6.9 ± 3.3% and 6.1 ± 4.6% at UnicCa® and SLActive®, respectively. After 2 weeks, the percentages had increased to 29.1 ± 11.9% and 21.6 ± 14.3%, respectively. After 4 and 8 weeks of healing, mean values of 46.3 ± 7.3% and 58.7 ± 15.1% at UnicCa® and 51.2 ± 16.1% and 68.9 ± 15.4% at SLActive® surfaces were found, respectively. None of the differences in percentages were statistically significant. Concomitantly, the old bone was resorbed at both surfaces from about 21-22% after 1 week to about 4-6% after 8 weeks of healing. Conclusions The osseointegration process onto moderately rough titanium implant surfaces of high hydrophilicity was very similar for two implant systems that were both nanotechnologically modified. [ABSTRACT FROM AUTHOR]

Background Cell interactions, adherence, and osseointegration at the bone-implant interface can be directly influenced by the surface properties of the titanium implant. Purpose To characterize osseointegration of Neoss® implants with conventional (control group) and hydrophilic (test group) surface treatments. Materials and Methods Six Labrador dogs received Neoss implants with conventional and hydrophilic surfaces. The bone-implant interfaces were evaluated 1 and 4 weeks after implantation, and osseointegration was evaluated using histological, histomorphometric, fluorescence, and resonance frequency analyses. The surfaces were also subjected to topographic and hydrophilicity analyses. Results The topographic analyses revealed increased surface roughness in the test group compared with the control group (surface area roughness 0.42 and 0.78 μm, respectively, for control and test group surfaces; p ≤ .05). The wettability values were higher in the test group (contact angles 67.2° and 27.2° for the control and test group surfaces, respectively; p ≤ .05). Implants in the test group also exhibited better stability, more bone-implant contact, and increased bone area compared with implants in the control group. Conclusion Neoss implants in the test group improved bone formation in the early stages of osseointegration compared with implants in the control group. [ABSTRACT FROM AUTHOR]

Background Dental implants have become essential in reconstructive dentistry. Primary healing is determined by the design of their surface. The aim of this pilot study has been to investigate whether the morphology of the sandblasted and acid-etched ( SLA®) surface remains unaffected after the insertion process into human bone. Materials and Methods Two edentulous-atrophied human jaw specimens were used. Six brand new Straumann Standard RN implants with an SLA® surface and having a diameter of 3.3 mm and a length of 12 mm were inserted. Another two implants of the same type, but not inserted into bone, served as a reference. After explantation, the four implants were cleaned in an ultrasonic bath and two were left uncleaned. All eight implants were inspected by SEM for qualitative surface changes. Results All four implants showed relevant changes of the topography at the apical thread flanks. The non-cleaned implants showed an almost complete coverage of the surface by a honeycomb-like structure, consistent with bone residues. The reference implants showed no changes. Discussion The results indicate that, for the osseointegration of dental implants, subtractive modifications of implant surfaces are less important than the reestablishment of the destroyed TiO2 layer. Further studies of other implant surfaces are required to verify the present results. [ABSTRACT FROM AUTHOR]

Background Bacteria are major contributors to the rising number of dental implant failures. Inflammation secondary to bacterial colonization and bacterial biofilm is a major etiological factor associated with early and late implant failure (peri-implantitis). Even though there is a strong association between bacteria and bacterial biofilm and failure of dental implants, their effect on the surface of implants is yet not clear. Purpose To develop and establish an in vitro testing methodology to investigate the effect of early planktonic bacterial colonization on the surface of dental implants for a period of 60 days. Materials and Methods Commercial dental implants were immersed in bacterial ( S treptococcus mutans in brain-heart infusion broth) and control (broth only) media. Immersion testing was performed for a period of 60 days. During testing, optical density and pH of immersion media were monitored. The implant surface was surveyed with different microscopy techniques post-immersion. Metal ion release in solution was detected with an electrochemical impedance spectroscopy sensor platform called metal ion electrochemical biosensor ( MIEB). Results Bacteria grew in the implant-containing medium and provided a sustained acidic environment. Implants immersed in bacterial culture displayed various corrosion features, including surface discoloration, deformation of rough and smooth interfaces, pitting attack, and severe surface rusting. The surface features were confirmed by microscopic techniques, and metal particle generation was detected by the MIEB. Conclusion Implant surface oxidation occurred in bacteria-containing medium even at early stages of immersion (2 days). The incremental corrosion resulted in dissolution of metal ions and debris into the testing solution. Dissolution of metal ions and particles in the oral environment can trigger or contribute to the development of peri-implantitis at later stages. [ABSTRACT FROM AUTHOR]

Background The influence of the implant micro and macrostructure on peri-implantitis is not fully understood. Purpose To determine the effect of ligature-induced peri-implantitis on three commercially available implant types. Materials and Methods Five beagle dogs were used. Two months following tooth extraction, three different implant types ( BIOMET 3i T3, BIOMET 3i, Palm Beach Gardens, FL, USA; Straumann Bone Level, Straumann GmbH, Basel, Switzerland; Nobel Replace Tapered, Nobel Biocare, Gothenburg, Sweden) were placed in a randomized fashion in each hemi-mandible. Peri-implantitis was initiated by ligature placement and soft diet. Ligatures were added every 2 weeks for a total of four ligature advancements. After 2 weeks, the ligatures were removed, oral hygiene measures initiated for 3 weeks, and clinical (probing depth, mucosal recession, bleeding on probing), intrasurgical (intrasurgical defect depth, intrasurgical defect width), and radiographic (radiographic bone level) parameters assessed. Results Nobel Replace Tapered implants showed significantly higher intrasurgical defect depth, intrasurgical defect width, probing depths, and radiographic bone level when compared to BIOMET 3i T3 or Straumann Bone Level implants. Straumann Bone Level implants showed largely similar clinical outcomes to BIOMET 3i T3. No significant differences between the groups were observed for mean mucosal recession. Conclusion In an experimental peri-implantitis model, Nobel Replace Tapered implants are associated with pronounced tissue loss. [ABSTRACT FROM AUTHOR]

Background Even though there are many studies available reporting on implant failures, there are few studies that follow implant failures over time in large populations. Purpose The purpose of this article is to present an overview of the annual incidence of reported implant failures for patients and operations over a 28-year period. Materials and Methods A total of 8,528 patients were consecutively provided with 39,077 implants in 10,719 implant operations during a 27-year period (1986-2012) at one specialist clinic. All patients with reported failures of implants during a 28-year routine follow-up period (1986-2013) were included, and data from the patients' files were retrieved and reported. Results Altogether, 857 patients (882 jaws/operations) were identified with one or more failures (10.0% of patients/8.5% of operations). Mean annual incidence of first failure showed obvious variations between years, even between seemingly clinically similar situations. However, incidence of first implant failure was higher for upper than lower jaws ( p < .05), within 1 year of surgery (69%) than after 1 year ( p < .05), and for implants with a turned surface compared with implants with a moderately rough surface ( p < .05). Conclusions With regard to annual failure incidence in relation to total number of operations over time, obvious variations in failure rate can be observed between seemingly similar clinical situations, as well as significant differences in incidence of first implant failure between the first year after surgery and later time points, between upper and lower jaws using implants with turned surfaces, and between operations to install implants with turned surfaces and those to install implants with moderately rough surfaces. [ABSTRACT FROM AUTHOR]

Atmospheric pressure plasma-jets could be an alternative method to remove bacterial biofilms on orthopaedic implants. Furthermore, plasma-exposure might support the proliferation of osteoblasts after cleaning implants by activating the implant surface. In this comparative in vitro study, the efficacy of five different plasma sources concerning removal of bacterial biofilms and influence on human osteoblast cell attachment was tested. Two plasma sources revealed a significant reduction of bacterial viability (>90%) and enhanced spreading of osteoblastic cells. Promising results and potential for local plasma-jet application dealing with implant-related infections caused by bacterial biofilms was demonstrated. [ABSTRACT FROM AUTHOR]

Objectives To study the combined effect of mechanical and chemical cleansing on a 4-day biofilm grown intra-orally on titanium discs with different surface characteristics. Material and methods Twenty subjects used a splint with two metal plates in the upper jaw. Each plate was placed in the premolar-molar region and carried four titanium discs with four different surface characteristics (OsseoSpeed™, TiOblast™, experimental and turned surface). After 4 days of biofilm growth, the discs were cleaned mechanically and chemically with saline or chlorhexidine. Following cleansing, microbial samples were obtained and analysed by culture. The titanium discs were processed for scanning electron microscope ( SEM) analysis. The experiment was repeated 3 days later using delmopinol or a mixture of essential oils during cleansing. Results The combination of mechanical and chemical cleansing was ineffective in complete biofilm removal from all four titanium discs. The microbiological analysis did not reveal any statistically significant differences between surface types or between cleaning agents regarding logarithmic mean counts of CFU for specific bacteria, aerobes, anaerobes or the TVC. Aerobes were more numerous than anaerobes on all surface types. The SEM analysis disclosed that the remaining biofilm on moderately rough surfaces (OsseoSpeed™, TiOblast™ and experimental) was complex and firmly attached, while the biofilm on turned surface had a pattern of spread bacteria forming less clusters. Conclusions Cleansing may call for prolonged time of chemomechanical debridement and/or more effective disinfectants to suppress biofilms on dental implant surfaces. [ABSTRACT FROM AUTHOR]