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Purpose: Marginal bone resorption (MBR) around dental implants may sometimes be a self-limiting condition due to balancing immunologic reactions against utilized materials rather than a progressive bacterial infection. Contrary to previous assumptions from ligature-induced experimental peri-implantitis studies, a recent 8-week experiment by the present authors showed that marginal ligatures trigger an inflammatory immune response, resulting in bone resorption around implants in the absence of plaque. The present study aimed to investigate whether this inflammatory/immunologic reaction attenuates or progresses toward implant failure after a longer healing time (12 weeks). Materials and Methods: Sterile silk ligatures were placed around the top of titanium (Ti) implants and compressed against the femoral cortical bone plate of six rabbits. A nonligated implant was used as a control. After 12 weeks of submerged healing, ground sections of implants and surrounding tissues were investigated with light microscopy. The marginal soft tissues were also analyzed using selected quantitative polymerase chain reaction (qPCR) markers. Results: Histologically, the ligatures were outlined by immune cells, including multinucleated giant cells (MNGCs), with adjacent fibrous encapsulation and resorbed peripheral bone that contrasted from the osseointegrated nonligated control implants. The difference in expression of qPCR markers was not significant, but > two-fold upregulation of markers CDIIb, IL1β, ARG1, NCF1, and CD4 and > twofold downregulation of CD8 indicated a mild, focal inflammatory/immune response against the ligatures compared to controls, with upregulation of M1 and M2 macrophages, neutrophils, and helper T-cells as well as downregulation of killer T cells. Further, the bone formation markers OC and ALPL were > two-fold downregulated (consistent with the lack of osseointegration of the ligatures) compared to control implants. Conclusions: Marginal silk ligatures trigger an inflammatory/immune response and aseptic bone resorption around implants. Compared to the previous 8-week study, the inflammatory reaction against the silk appears to attenuate with time, with only a mild persisting inflammation that may block osseointegration; instead, a fibrous tissue encapsulation-type reaction is maintained. This may explain why traditional ligature experiments have required regular exchange of ligatures for the bone resorption to progress. [ABSTRACT FROM AUTHOR]

Purpose: To present a survival analysis of 133 consecutively placed moderately rough implants, all with a total follow-up of 20 years. Materials and Methods: A total of 133 implants of the same brand placed in 46 patients at the same county clinic in Sweden were followed up prospectively over 20 years and analyzed for survival and bone height, the latter evaluated in periapical radiographs. Results: A total of 7 implants failed, 4 of which were in the same patient. Implant failure was associated with a combination of smoking and bruxism in 5 of the 7 failed cases. A 20-year survival rate of 94.7% was observed. Average marginal bone loss (MBL) at 20 years of follow-up was 0.543 ± 1.193 mm, with 9 implants having more than 2 mm of MBL. A total of 20 patients with 25 implants dropped out of the study; however, if death of the patient is excluded as a dropout reason, only 3 implants in 3 patients were unaccounted for. Conclusions: Good clinical results in the 95% survival range were observed with moderately rough implants over a 20-year follow-up period. [ABSTRACT FROM AUTHOR]

The article urges for the dental profession to rethink foreign body osseointegration and consider graftless procedures. It refers to osteoimmunomodulation as a walling-off mechanism that protects the host immune system, which decides whether bone formation or bone resorption will dominate in the presence of a foreign element. It cautions about possible bacterial invasion given the failure of osteoimmunomodulation or bone loss due to reaction to foreign body like titanium oral implants.

Purpose: After some initial setbacks in the 1970s, ceramic implants seem to be a promising alternative to titanium implants. Since the surface of an implant system represents the interface to surrounding biologic structures, the study focuses on cleanliness and surface topography. Clinical documentation of the corresponding systems completes the picture and allows a better evaluation of zirconia implant systems. Materials and Methods: Five different ceramic implant systems were selected randomly and purchased via blind-shopping: Z5s (Z-Systems), ZiBone (COHO), W implant (TAVDental), ceramic. implant (vitaclinical), and BioWin!/Standard Zirkon Implantat (Champions-Implants/ZV3 system). Three samples of each implant system underwent scanning electron microscopy (SEM) imaging and elemental analysis (EDS). Where appropriate, subsequent Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) was performed to identify the chemical nature of impurities. Surface topography was evaluated, and a search for clinical trials in the PubMed database, on the websites and by written request to each dental implant manufacturer, was performed. Results: Surfaces of Champions implants (ZV3) and Z-Systems implants were relatively clean, whereas the other investigated surfaces of vitaclinical, TAV Dental, and ZiBone implants all displayed organic contaminations on their surfaces. Four of the investigated ceramic implants showed a moderately rough implant surface. Only the vitaclinical ceramic. implant had minimal surface roughness. Three ceramic designs--vitaclinical, ZV3, and Z-Systems--had clinical trials documented with up to 3 years of follow-up and results varying between 82.5% and 100% survival. TAV Dental W and ZiBone implant systems lacked properly conducted clinical recording of results. Conclusion: The results of this study showed that it is technically possible to produce zirconia implants that are largely residue-free. On the other hand, the variety of significant residues found in this analysis raises concerns, as contamination may lead to undesirable biologic effects. The lack of clinical studies in peer-reviewed journals does not seem to be relevant for the approval of marketing, nor does the lack of surface cleanliness. In the authors' opinion, a critical analysis of these aspects should be included in a more stringent future analysis prior to the marketing of oral implant systems. [ABSTRACT FROM AUTHOR]

Purpose: To compare clinical and esthetic outcomes between immediately loaded single implants placed with and without a fully guided surgical procedure.Materials and Methods: Patients with a missing maxillary tooth (second premolar to second premolar) were considered for inclusion in this 1-year prospective nonrandomized study. Exclusion criteria were general health contraindications for oral surgery besides the need for bone grafting or ridge augmentation. One group received digital implant planning, fully guided surgery, and immediate loading (DIL). The other group received freehand surgery and immediate loading (IL). Outcome measures were implant survival, marginal bone loss, soft tissue changes, papilla index, pink and white esthetic scores (PES and WES, respectively), and patient-reported outcome measures (PROMs).Results: Two of 21 implants failed in the DIL group soon after placement, resulting in a 1-year implant survival rate of 90.5%, while no implants failed in the IL group. Significantly higher papilla index scores and lower soft tissue changes were found for the DIL group compared to the IL group. No differences were found after 1 year regarding marginal bone loss, PES, WES, or PROMs.Conclusion: Within the limitations of this study, immediate loading in combination with fully guided surgery might negatively affect implant survival. Immediate loading, fully guided surgery, and a digital workflow appear to have a positive effect on early soft tissue adaptation. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present evidence that supports the notion that the primary reason behind marginal bone loss and implant failure is immune-based and that bacterial actions in the great majority of problematic cases are of a secondary nature. Materials and Methods: The paper is written as a narrative review. Results: Evidence is presented that commercially pure titanium is not biologically inert, but instead activates the innate immune system of the body. For its function, the clinical implant is dependent on an immune/inflammatory defense against bacteria. Biologic models such as ligature studies have incorrectly assumed that the primary response causing marginal bone loss is due to bacterial action. In reality, bacterial actions are secondary to an imbalance of the innate immune system caused by the combination of titanium implants and ligatures, ie, nonself. This immunologic imbalance may lead to marginal bone resorption even in the absence of bacteria. Conclusion: Marginal bone loss and imminent oral implant failure cannot be properly analyzed without a clear understanding of immunologically caused tissue responses. [ABSTRACT FROM AUTHOR]

Zygomatic-related implant rehabilitation differs from traditional implant treatment in biomechanics, clinical procedures, outcomes, and eventual complications such as soft tissue incompetence or recession that may lead to recurrent sinus/soft tissue complications. The extreme maxillary atrophy that indicates the use of zygomatic implants prevents use of conventional criteria to describe implant success/failure. Currently, results and complications of zygomatic implants reported in the literature are inconsistent and lack a standardized systematic review. Moreover, protocols for the rehabilitation of the atrophic maxilla using zygomatic implants have been in continuous evolution. The current zygomatic approach is relatively new, especially if the head of the zygomatic implant is located in an extramaxillary area with interrupted alveolar bone around its perimeter. Specific criteria to describe success/survival of zygomatic implants are necessary, both to write and to read scientific literature related to zygomatic implant-based oral rehabilitations. The aim of this article was to review the criteria of success used for traditional and zygomatic implants and to propose a revisited Zygomatic Success Code describing specific criteria to score the outcome of a rehabilitation anchored on zygomatic implants. The ORIS acronym is used to name four specific criteria to systematically describe the outcome of zygomatic implant rehabilitation: offset measurement as evaluation of prosthetic positioning; rhino-sinus status report based on a comparison of presurgical and postsurgical cone beam computed tomography in addition to a clinical questionnaire; infection permanence as evaluation of soft tissue status; and stability report, accepting as success some mobility until dis-osseointegration signs appear. Based on these criteria, the assessment of five possible conditions when evaluating zygomatic implants is possible. [ABSTRACT FROM AUTHOR]

The aim of the present systematic review was to evaluate reported survival rate and marginal bone (MBL) loss of implants with different surface roughness and followed up for 10 years or longer. For the majority of the 62 included clinical studies, no direct comparison between different surfaces was made, thus our report is mainly based on reported survival rates and marginal bone loss for individual implant brands with known surface roughness. The survival rate was 82.9 to 100% for all implants after 10 or more years in function and the marginal bone loss was, on average, less than 2.0 mm for all implant surfaces included, i.e. turned, titanium plasma sprayed (TPS), blasted, anodised, blasted and acid-etched but the turned surface in general demonstrated the smallest MBL. However, the survival rates were in general higher for moderately rough surfaces. The roughest TPS surface demonstrated the highest probability for failure, while the anodised showed the lowest probability. In conclusion, the present systematic review demonstrates that it is possible to achieve very good long- term results with all types of included surfaces. [ABSTRACT FROM AUTHOR]

The article provides the highlights of the Foundation for Oral Rehabilitation (FOR) Consensus Conference held at the Catholic University of Leuven, Belgium, on November 16 and 17, 2017. The conference discussed the diagnosis, avoidance and management of complications of implant-based treatments. It presented several review papers on surgical complications, foreign body reactions and intraoral radiography.

Aim: To describe general observations of immunological reactions to foreign materials and to realize that CP titanium gives rise to a foreign body reaction with subsequent bone embedment when placed as oral implants. To analyse the possibility of titanium allergy. Materials and methods: The present paper is of a narrative review type. Hand and Medline searches were performed to evaluate marginal bone loss of oral implants and the potential of titanium allergy. Results: Immunological reactions to foreign substances include Type I hypersensitivity reactions such as allergy, Type II hypersensitivity reactions characterised by IgM or IgG antibodies that may react with blood group antigens at transfusion, and Type III hypersensitivity caused by antigen-antibody immune complexes exemplified by acute serum sickness. There is also Type IV hypersensitivity, or delayed hypersensitivity, which is typically found in drug and foreign body reactions. It proved very difficult to find a universally acceptable definition of reasons for marginal bone loss around oral implants, which lead to most varying figures of so-called peri-implantitis being 1% to 2% in some 10-year follow-up papers to between 28% and 56% of all placed implants in other papers. It was recognised that bone resorption to oral as well as orthopaedic implants may be due to immunological reactions. Today, osseointegration is seen as an immune-modulated inflammatory process where the immune system is locally either up- or downregulated. Titanium implant allergy is a rare condition, if it exists. The authors found only two papers presenting strong evidence of allergy to CP titanium, but with the lack of universally accepted and tested patch tests, the precise diagnosis is difficult. Conclusions: CP titanium acts as a foreign body when placed in live tissues. There may be immunological reasons behind marginal bone loss. Titanium allergy may exist in rare cases, but there is a lack of properly designed and analysed patch tests at present. [ABSTRACT FROM AUTHOR]

The author discusses his scholarship pursuits, professional journeys, and published works related to Per-Ingvar Branemark's research on osseointegration, the history of prosthodontic therapy, and forecasts regarding osseointegration and prosthodontics. Topics include his participation in a randomized clinical trial using osseointegration as anchorage for a hip arthroplasty, and his encouragement of prosthodontists to study published papers to gain knowledge despite the possibility for papers to misinterpret results.

Purpose: To investigate the biomechanical and immunological reactions to coated and non-coated blasted PEEK implants in vivo after 12 weeks and review the associated literature. Methods: Two osteotomy sites were performed in each proximal tibia of 10 lop-eared rabbits (n= 4 per rabbit). Each rabbit received a randomly placed (1) blasted zirconium phosphate nano-coated PEEK- (nano-ZrP), (2) blasted PEEK- (PEEK) and (3) titanium implant (Ti) and an empty sham site. At 12 weeks, removal torque of all implants and biological investigation with qPCR was performed. The implant surfaces were analyzed prior to insertion with interferometry, SEM and XPS. Results: The interferometry analysis showed that there was no difference in roughness for the uncoated PEEK compared to the ZrP coated PEEK implants. The titanium implants were considerably smoother (Sa= 0.23 kim) than the uncoated Sa= 1.11 pm) and ZrP coated PEEK implants (Sa= 1.12 jim). SEM analysis on the PEEK implants corroborated the interferometry results; no difference in structure between the uncoated vs. the ZrP coated PEEK was visible on the micrometer level. At higher magnifications, the ZrP coating was visible in the SEM as a thin, porous network. All tested implants displayed osseointegration with the highest RTQ for nano-ZrP (18.4 Ncm) followed by PEEK (14.5 Ncm) and Ti (11.5 Ncm). All implants activated the immune system, with elevated macrophage and M2 macrophage qPCR markers at 12 weeks compared to the sham site. [ABSTRACT FROM AUTHOR]

Purpose: To assess the influence of several factors on the prevalence of dental implant failure, with special consideration of the placement of implants by different dental surgeons.Materials and Methods: This retrospective study is based on 2,670 patients who received 10,096 implants at one specialist clinic. Only the data of patients and implants treated by surgeons who had inserted a minimum of 200 implants at the clinic were included. Kaplan-Meier curves were stratified with respect to the individual surgeon. A generalized estimating equation (GEE) method was used to account for the fact that repeated observations (several implants) were placed in a single patient. The factors bone quantity, bone quality, implant location, implant surface, and implant system were analyzed with descriptive statistics separately for each individual surgeon.Results: A total of 10 surgeons were eligible. The differences between the survival curves of each individual were statistically significant. The multivariate GEE model showed the following variables to be statistically significant: surgeon, bruxism, intake of antidepressants, location, implant length, and implant system. The surgeon with the highest absolute number of failures was also the one who inserted the most implants in sites of poor bone and used turned implants in most cases, whereas the surgeon with the lowest absolute number of failures used mainly modern implants. Separate survival analyses of turned and modern implants stratified for the individual surgeon showed statistically significant differences in cumulative survival.Conclusion: Different levels of failure incidence could be observed between the surgeons, occasionally reaching significant levels. Although a direct causal relationship could not be ascertained, the results of the present study suggest that the surgeons' technique, skills, and/or judgment may negatively influence implant survival rates. [ABSTRACT FROM AUTHOR]

Purpose: The aims of this clinical study were to retrospectively evaluate implant survival, patient satisfaction, and radiographic, clinical, and esthetic outcomes following single-implant treatment. Materials and Methods: Eighty-seven patients, with a total of 126 implants (XiVE S, Dentsply Implants), who received single implant-retained crowns between 2004 and 2011 were retrospectively evaluated. Implant survival, marginal bone levels (MBL), changes in implant/mesial tooth vertical relationship, pink esthetic score (PES), white esthetic score (WES), patient assessment of the esthetics (visual analog scale), and oral health impact profile (OHIP-14) were evaluated. Results: Altogether, 59 patients with a total of 85 implants attended a final clinical and radiographic follow-up examination. The mean ages of males and females at implant placement were 19.78 and 22.58 years, respectively. The mean total follow-up time from the implant surgical date was 7.51 years. The 5-year implant clinical survival rate (CSR) was 98.4% (95% CI: 96.3%-100%), and crown CSR was 91.8% (95% CI: 86.3%-97.3%). The overall mean change in MBL was -0.19 mm. No significant differences were found between the different implant diameters (3.0, 3.4, and 3.8 mm) with regard to change in MBL. Mean increase in implant infraposition was 0.13 mm. With regard to esthetics, mean initial and final total PES were 9.61 and 11.49, respectively (P < .001). The mean WES was 6.48 at follow-up. Patients' mean assessment of soft tissue esthetics and implant-supported crown appearance were 73.5 and 82.1 (maximum score 100). At the follow-up examination, the additive OHIP-14 score was 16.11. Conclusion: This retrospective study of XiVE S implants found excellent survival rates and showed good clinical outcomes concerning patient-centered findings, esthetics, and marginal bone preservation. In context, it is important to stress that this study consisted of mostly young patients with agenesis who were treated by experienced clinicians. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the association between the intake of proton pump inhibitors (PPIs) and the risk of dental implant failure. Materials and Methods: The present retrospective cohort study is based on patients consecutively treated between 1980 and 2014 with implant-supported/retained prostheses at one specialist clinic. Modern endosseous dental implants with cylindrical or conical design were included, and only complete cases were considered; ie, only those implants with information available for all variables measured were included in the regression model analysis. Zygomatic implants and implants detected in radiographies but without basic information about them in the patients' files were excluded from the study. Implant- and patient-related data were collected. Multilevel mixed-effects parametric survival analysis was used to test the association between PPI exposure (predictor variable) and risk of implant failure (outcome variable), adjusting for several potential confounders. Results: A total of 3,559 implants were placed in 999 patients, with 178 implants reported as failures. The implant failure rates were 12.0% (30/250) for PPI users and 4.5% (148/3,309) for nonusers. A total of 45 out of 178 (25.3%) failed implants were lost up to abutment connection (6 in PPI users, 39 in nonusers), with an early-to-late failure ratio of 0.34:1. The intake of PPIs was shown to have a statistically significant negative effect for implant survival rate (HR 2.811; 95% CI: 1.139 to 6.937; P = .025). Bruxism, smoking, implant length, prophylactic antibiotic regimen, and implant location were also identified as factors with a statistically significant effect on the implant survival rate. Conclusion: This study suggests that the intake of PPIs may be associated with an increased risk of dental implant failure. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the evidence of a correlation between the expertise of surgeons and the survival rate of dental implants.Materials and Methods: An electronic search in four databases (MEDLINE, EMBASE, SCOPUS, and the Cochrane Library) was performed for publications from their inception to May 2016 and was supplemented by manual searches. Prospective and retrospective cohorts were included if they met the following criteria: (1) the presence of an exposed group (inexperienced surgeons); and (2) the presence of a control group (experienced surgeons). Meta-analyses were performed to evaluate the effect of expertise on implant failure.Results: Of 609 potentially eligible articles, 8 were included in the qualitative analysis and 6 in the quantitative synthesis. Two meta-analyses were performed for different definitions of experienced surgeons. In the first meta-analysis, which included four retrospective comparative studies that defined experienced professionals as specialists, the experience of the surgeon did not significantly affect the implant failure rate (P = .54), with an odds ratio (OR) of 1.24 (95% CI, 0.62-2.48). In the second meta-analysis, which included two retrospective studies that defined experienced surgeons as professionals that had placed more than 50 implants, the expertise of the surgeon did significantly affect the implant failure rates (P = .0005), with an OR of 2.18 (95% CI, 1.40-3.39).Conclusion: The data from the included publications suggest that surgical experience did not significantly affect implant failure when considering experience based on specialty but were significantly affected when considering experience based on the number of implants placed. Further standardized prospective studies with a control of confounding factors are needed to clarify the role of surgical expertise on implant survival rates. [ABSTRACT FROM AUTHOR]

Purpose: A moderately rough anodized titanium implant surface (TiUnite) was introduced in 2000. This review and meta-analysis aimed to assess implant survival and marginal bone level (MBL) changes documented in the literature. Materials and Methods: Repeated literature searches on dental implants were conducted, with the final search on October 7, 2016. The inclusion criteria were: prospective study, minimum of 20 patients, at least 12 months follow-up postloading, and TiUnite implant survival reported. Regression analysis was performed on implant survival and MBL change from implant surgery. Peri-implantitis as defined by the primary authors was reported at the patient level. Results: One hundred six out of 32,519 publications on dental implants met the inclusion criteria. Implant survival rates at 1 year were 99.50% at the implant level and 99.12% at the patient level, and survival rates at 10 years were 95.14% at the implant level and 91.50% at the patient level. Mean MBL change at 1 year was -0.409 mm at the implant level and -0.413 mm at the patient level, and at 5 years, it was -0.886 mm at the implant level and -1.029 mm at the patient level. Nineteen studies (18%) specifically reported peri-implantitis in 64 out of 1,229 patients with a mean followup of 47.89 months, indicating a prevalence of 5.20% at the patient level. Conclusion: Based on a metaanalysis of prospective studies, implants with the TiUnite surface provide a predictable treatment modality in a variety of indications. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to test the null hypothesis that there is no difference in implant failure rates, marginal bone loss, and postoperative infection for implants inserted in bone with different qualities and quantities according to the classification of Lekholm and Zarb.Materials and Methods: An electronic search was undertaken in January 2015 for randomized and nonrandomized human clinical studies.Results: A total of 94 publications were included. When bone sites of different qualities were considered, the results suggested the following comparative implant failure rates: 1 > 2, 1 > 3, 3 > 2, 4 > 1, 4 > 2, and 4 > 3. Sensitivity analyses suggested that when implants inserted in bone qualities 1 and 2 and 1 and 3 were compared, oxidized and sandblasted/acid-etched surfaces showed a decrease in significant difference in failures compared with turned implants. The same is not true for failure of implants inserted in bone quality 4 compared to failure of implants in all other bone qualities. When bone sites of different quantities were considered, the following comparative implant failure rates were observed: A > B, A > C, A < D, B < C, B < D, C < D, E > A, E > B, E > C, E > D. Due to insufficient information, meta-analyses for the outcomes postoperative infection and marginal bone loss were not performed.Conclusion: Sites with poorer bone quality and lack of bone volume may statistically affect implant failure rates. Implant surfaces may play a role in failure of implants in different bone qualities. [ABSTRACT FROM AUTHOR]