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A total of 57 interproximal restorations invading the supracrestal tissue attachment were evaluated in terms of crestal bone loss over a mean period of 15 years (10 to 23 years). The distance from the cavity margin to the bone was measured at T0 (after the restoration; baseline) and controlled using radiographs and a measurable landmark. The mean vertical bone loss was 0.46 mm, with a 96.49% survival rate. Smoking habits (P = .02) and tooth type (P = .03) significantly affected bone loss. The proposed technique could help the clinician in adopting a minimally invasive approach in the treatment of heavily compromised teeth. Future research with rigorous study designs would be interesting to guide the clinical decision-making. [ABSTRACT FROM AUTHOR]

Tooth extractions can result in alveolar bone dimensional changes, necessitating additional bone grafting for implant placement. Alveolar ridge preservation (ARP) aims to counteract postextraction changes. This case series evaluates the bone regenerative properties of a freeze-dried bone allograft (FDBA) and the clinical outcomes of implants in grafted extraction sites. A total of 33 patients were enrolled, undergoing single/multiple tooth extractions followed by ARP. Biopsy samples were harvested during implant placement for histologic and histomorphometric analysis. Clinical outcomes included marginal bone loss and pink esthetic score (PES). Twenty-five patients completed the study. FDBA-augmented sockets exhibited new bone formation adjacent to graft particles. Implants (n = 25) showed 100% survival and success rates at 1 and 2 years. PES improved significantly over time (P < .001), while marginal bone loss did not significantly differ at 1 and 2 years (P = .096). Specimens showed trabecular bone, residual FDBA particles, and marrow spaces. High magnification revealed immature bone and woven bone bridges around graft particles. No inflammatory cells were observed. This case series provides valuable insights into ARP performed with FDBA (as implants were placed after 3 months of healing without any additional bone augmentation), the histologic outcomes were favorable, and implants were successful after a 2-year follow-up period. [ABSTRACT FROM AUTHOR]

Volumetric resorption of the alveolar ridge often occurs in both horizontal and vertical directions following tooth extraction. There is a specific lack of evidence for alveolar ridge reconstruction at molar and premolar sites with severe bone resorption. This randomized controlled trial used 3D and linear analyses to evaluate volumetric changes of the alveolar bone following alveolar ridge reconstruction (ARR) at molar and premolar sites with severe bone resorption as compared to unassisted socket healing before implant placement. A total of 31 patients (15 men, 16 women) with > 50% hard tissue loss in one or more socket walls were recruited and randomized into either a test group (postextraction ARR using deproteinized bovine bone mineral with 10% collagen [DBBM-C] and platelet-rich fibrin [PRF] with a resorbable collagen membrane) or a control group (natural healing after extraction). The clinical, linear, and volumetric implant-related and patient-reported outcomes were analyzed after 4 months of healing. Linear bone assessments revealed significantly greater ridge width gains in the test group (25% in the mesial, midfacial, and distal aspects) and less reduction of vertical bone ridge than in the control group (P < .05). Further, volumetric bone remodeling was significantly higher in the test group (35.1% ± 34.9% for ARR, 14.2% ± 12.8% for control; P < .05). Patient-reported discomfort and keratinized mucosal changes were comparable between groups. ARR with a combination of DBBM-C, PRF, and a resorbable membrane at posterior sites with a severe socket wall deficiency (> 50% bone loss) is a safe and more capable therapeutic method when compared to natural healing and unassisted sockets. Collectively, the present analyses demonstrate that ARR represents an efficient method to maintain and augment crestal bone at posterior extraction sites with severe bone defects when assessed after 4 months of healing. [ABSTRACT FROM AUTHOR]

Purpose: To explore the contribution of paired-related homeobox 1-positive (Prrx1+) cells to the implant-induced osseointegration process in adult alveolar bone and the potential underlying mechanisms. Materials and Methods: Cre recombinase-induced lineage tracing and cell ablation were conducted in a murine dental implant model. Scratch and transwell assays were used to assess MC3T3-E1 cell migration after paired-related homeobox 1 overexpression. Single-cell RNA sequencing was applied to identify potential genes involved in Prrx1+ cell-driven osteogenesis. Results: Prrx1+ cells were observed to accumulate in the peri-implant area in a time-dependent manner; the number of these cells was found to reach its maximum on day 14. Osseointegration in mice was noticeably impaired after ablation of Prrx1+ cells. Further, it was discovered that Prrxl promotes MC3T3-E1 cell migration, a process which is indispensable for sound healing of peri-implant tissue. Finally, semaphorin 3C (Sema3C) was detected exclusively and abundantly expressed by Prrx1+ cells. Knockdown of Sema3C in Prrx1+ cells significantly weakened their osteogenic potential. Conclusions: Our data suggest that Prrx1+ cells contribute to the osseointegration process under stress stimulation and Sema3C may play a critical role in Prrx1+ cell-driven osteogenesis. Prrxl could significantly promote MC3T3-E1 cell migration. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical performance of implant-prosthetic rehabilitations carried out using ceramic-coated CAD/ CAM titanium abutments. Materials and Methods: Thirty implants were placed in 30 patients and rehabilitated with 30 single crowns attached to CAD/CAM titanium abutments. A conventional procedure was applied, implants were placed after postextraction socket healing, and prosthetic restorations were placed after implant healing. Implant lengths ranged from 6 to 15 mm, and widths were 3.6, 4.2, and 4.8 mm. At the time of prosthesis delivery (T0), after 2 years (T1), and after 5 years (T2), the Plaque Index (PI), bleeding on probing (BoP), pocket probing depth (PPD), marginal bone level (MBL), and pink/white esthetic scores (PES/WES) were evaluated for each implant. Results: No patient dropped out of the study during the follow-up period. All 30 implants were clinically successful 5 years after prosthesis delivery (survival rate: 100%) and showed no signs of peri-implant infection. Peri-implant soft tissues were in good health (BoP at T2: 0% in 73% of patients; 25% in 13% of patients; 50% in 10% of patients; and 75% in 3% of patients). The mean PPD was 2.05 ± 0.56 mm at T0, 1.992 ± 0.6 mm at T1, and 1.867 ± 0.439 mm at T2. The mean MBL was 0.413 ± 0.440 mm at T0, 0.306 ± 0.388 mm at T1, and 0.263 ± 0.368 mm at T2. The mean PES, WES, and PES/WES indices (7.43 ± 1.04, 7.57 ± 0.82, and 15.00 ± 1.17, respectively) indicate good integration of soft tissues, satisfactory esthetics, and overall positive outcomes. Conclusions: The success rates, maintenance of MBLs, and periodontal and esthetic indices suggest the validity of implant-prosthetic rehabilitations with CAD/CAM abutments in cases of single crowns. [ABSTRACT FROM AUTHOR]

Purpose: To summarize and analyze all the evidence available concerning marginal bone loss (MBL) and implant failure between tilted and axial implants. Materials and Methods: An electronic literature search was conducted without any language restrictions, and only systematic reviews with meta-analysis or meta-analysis studies were included. Relative risks (RRs) and the differences in mean (MD) were calculated with 95% confidence intervals (CIs) for the assessed outcomes (in mm) of implant failure and MBL. Results: In total, eight studies were included. Based on the short-term results, a nonsignificant mean difference (MD = 0.00; 95% CI; -0.01-0.02; P value = .75) was recorded between tilted and axial implants supporting full-arch dentures. A significant mean difference was recorded at 3-year follow-up (MD = 0.08 95% CI = 0.05-0.11; P value < .00001) and at long-term follow-up (MD = 0.18; 95% CI = 0.15-0.20; P value < .00001). A nonsignificant difference was observed between tilted and axial implants regarding implant failure (RR = 1.02; 95% CI = 0.85-1.23; P value = .81). Conclusions: Based on the high- and moderate-quality studies with low risk of bias included in this review, no significant difference in outcome regarding implant failure was observed between tilted and axial implants supporting full-arch or fixed partial dentures. [ABSTRACT FROM AUTHOR]

Purpose: To conduct a systematic review and meta-analysis to examine the impact of titanium (Ti) base-supported single-implant restorations on peri-implant conditions. Materials and Methods: Six randomized controlled trials (RCTs) comprising 274 implants met the inclusion criteria and were chosen for data analysis. A random-effects model was employed for the meta-analysis. Results: Data from this study revealed that the Ti-base group exhibited a small but statistically significant increase in peri-implant marginal bone loss (MBL; mean difference = 0.088 mm; 95% CI = 0.003 to 0.17; P = .041) compared to the one-piece abutment group. These effects were consistent in the subgroup analysis of regularly threaded implants compared to the microthreaded subgroup. No significant differences were observed between the Ti-base group and the abutment group concerning probing depth (PD), bleeding on probing (BoP), and the risk of prosthetic-related complications. Conclusions: The use of a Ti-base in a single implant-supported restoration is associated with a slight increase in peri-implant MBL, while other peri-implant health parameters show no significant correlation. Therefore, the evidence of the impact that Ti-bases have on the peri-implant conditions of single implant-supported restorations is insufficient based on the findings of the present meta-analysis. [ABSTRACT FROM AUTHOR]

Healing outcomes of periodontal and implant-related regenerative procedures are closely related to wound stability, which is partially determined by biomechanical properties and behaviors of oral mucosal tissues. Studies on soft tissue behavior under biomechanical forces in oral regeneration models are scarce. Thus, this review aims to (1) contrast the microstructural differences between the attached gingiva (AM) and lining (LM) mucosa; (2) evaluate biomechanical behaviors of the two mucosal types; and (3) relate residual flap tension to the prevalence of wound opening after regenerative procedures. Compositional and structural differences between the AM and LM explain their biomechanical property differences. Wound destabilizers, including tissue recoil stemming from its viscoelastic property, muscle pull, and inflammatory edema (created after the flap-releasing procedure for primary wound closure) interfere with wound stability. Residual flap tension < 0.05 N is a prerequisite for sustained wound closure. Tissues under stress can exert negative cellular changes, resulting in necrosis and wound dehiscence. Biomechanical properties and the variations between AM and LM dictate the degree of wound stability. Efforts should be made to reduce the negative impact of the potential destabilizers to optimize wound stability. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to evaluate the efficacy of alveolar ridge preservation (ARP) therapy compared with unassisted socket healing (USH) in attenuating interproximal soft tissue atrophy. Adult patients who underwent maxillary single-tooth extraction with or without ARP therapy were included. Surface scans were obtained and CBCT was performed to digitally assess interproximal soft tissue height changes and measure facial bone thickness (FBT), respectively. Logistic regression models were conducted to investigate the individual effect of demographic and clinical variables. Ninety -six subjects (USH = 49; ARP = 47) constituted the study population. Linear soft tissue assessments revealed a significant reduction of the interproximal soft tissue over time within and between groups (P < .0001). ARP therapy significantly attenuated interproximal soft tissue height reduction compared to USH: -2.0 ± 0.9 mm mesially for USH vs -1.0 ± 0.5 mm mesially for ARP; -1.9 ± 0.7 mm distally for USH vs -1.1 ± 0.5 mm distally for ARP (P < .0001). Thin (< 1 mm) facial bone thickness (FBT) upon extraction was associated with greater interproximal soft tissue atrophy compared to thick FBT (> 1 mm), independent of the treatment received (P < .0001). Nevertheless, ARP therapy resulted in better preservation of interproximal soft tissue height, especially in thin bone phenotype, by a factor of 2 for the mesial site (+1.3 mm) and by a factor of 1.6 for the distal site (+0.9 mm). This study demonstrated that ARP therapy largely attenuates interproximal soft tissue dimensional reduction after maxillary single-tooth extraction compared to USH. [ABSTRACT FROM AUTHOR]

This study compared the survival, marginal bone loss (MBL), and prosthetic complications of 4.5-mm extra-short implants and longer implants splinted to the short implants via the restoration. A retrospective controlled cohort study was performed. The 4.5-mm extra-short group (study group; SG) included 48 consecutively placed implants. The control group (CG) included 48 implants splinted to the extra-short implants. The same surgical team treated the 39 included patients, and all implants were restored with a screw-retained fixed restoration and intermediate abutments. Immediate and conventionally loaded implants were included. All implants were in function during the follow-up period (14 ± 3.4 and 17 ± 13 months for SG and CG, respectively). No differences in technical complications were observed between the groups (one and two cases of screw loosening for SG and CG, respectively; two provisional prosthesis fractures for SG; P = .310). Marginal bone stability was similar for SG and CG at the mesial level (-0.01 ± 0.28 mm for SG vs -0.18 ± 0.72 mm for CG; P = .270) and at the distal level (0.02 ± 0.39 mm for SG vs -0.18 ± 0.68 mm for CG; P = .076). The same good clinical performance could be observed for 4.5-mm implants and longer implants under the same prosthesis. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the influence of immediate loading on the osseointegration and bone density of implants placed in a healed alveolar bone crest and supporting single crowns. Materials and Methods: Two solid titanium transmucosal mini-implants were placed in the distal regions of the mandible in 14 patients. One mini-implant was immediately functionally loaded, whereas the other was left unloaded. After 2 months of healing, biopsy samples were retrieved and the levels of new bone, old bone, and total bone (new + old) were assessed. Results: Histologic examination was performed on biopsies from 12 patients (n = 12). The new bone-to-implant contact percentage (BIC%) was 40.3% ± 16.8% and 55.1% ± 19.1% (P = .043) at the unloaded and loaded sites, respectively; in addition, the total BIC% was 44.9% ± 17.0% and 59.5% ± 18.8%, respectively (P = .034). The new bone density was 45.9% ± 11.6% for the unloaded implants and 45.9% ± 16.7% for the loaded implants (P = .622). Conclusions: Immediate loading had a positive effect on bone apposition at the implant surface, but no effect on bone density was observed after 2 months of healing. [ABSTRACT FROM AUTHOR]

Purpose: To assess the impact of implant placement at different time intervals on the esthetic and clinical outcomes in the esthetic zone. Materials and Methods: A literature screening was conducted in PubMed (MEDLINE), ScienceDirect, and Cochrane databases. Relevant articles were included according to selection criteria and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data was collected from studies published from 2017 to 2022 in English. Results: Nine articles were included, in which a total of 495 implants were placed; 250 of the implants were immediate, 109 were early, and 136 were delayed. Immediate implant placement (IIP) showed no statistically significant difference in Pink Esthetic Score (PES) compared with delayed implant placement (DIP). IIP showed significantly higher PES in comparison with early implant placement (EIP) (mean difference [MD] = -0.76; 95% CI = -1.50 to -0.02; P = .04). The probing depth (PD) was considerably greater for immediate implants than for delayed implants (MD = -0.62; 95% CI = -1.05 to -0.18; P = .005), and the Plaque Index (PI) was statistically greater for early implants compared with immediate implants (MD = 0.15; 95% CI = 0.11 to 0.19; P < .00001). All other soft tissue outcomes showed equal results. The marginal bone loss (MBL) was statistically higher in early implants compared with immediate implants (MD = 0.09; 95% CI = 0.02 to 0.16; P = .02). Conclusions: IIP had significantly superior PES, MBL, and PI results when compared with EIP. The PD was significantly higher for immediate implants compared with delayed implants. All other outcomes showed no significant difference between the three implant groups. It is important to highlight the limitations of this review such as the small number of studies included and the few reports on esthetic indices. [ABSTRACT FROM AUTHOR]

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 explore the effect of adding an allogeneic soft tissue graft at the time of single implant placement using a fully digital workflow for implant placement and restoration without making either analog or digital impressions. Materials and Methods: A prospective randomized clinical study was performed enrolling 39 participants requiring single-tooth implants. The patients were randomized into one of two groups: (1) the graft group, which received an allogeneic dermal graft at the time of implant placement (n = 19), or (2) the nongraft group (n = 20). A fully digital surgical and restorative protocol was implemented for both groups. Intraoral scans were taken before implant placement (T0), at the time of final crown delivery (T1), and 1 year after placement (T2). Intraoral scans were aligned using Geomagic Control X 2020 software, and linear and volumetric changes in buccal tissues were measured at T0, T1, and T2. Implant survival, probing depths (PDs), and complications were recorded. Participants were asked to complete an Oral Health Impact Profile (OHIP)-14 survey at T0 and T2. Marginal bone levels were measured at T0 and T2 on periapical radiographs. Results: Overall, 39 participants completed surgery and restoration in the incisor, canine, premolar, and molar sites. Two early failures were recorded in central incisor positions (95% survival). Crown delivery without complication from the digital workflow (impressionless) was achieved for 36 out of 39 cases (92%), and implant depth control was the main challenge. At 1 year, 37 participants attended the follow-up appointment. Both groups showed gain in buccal tissue thickness without significant differences between the two groups for both linear and volumetric measurements (P > .05). Soft tissue grafting was associated with minimal added morbidity. The interproximal marginal bone changes were recorded as follows: -0.16 mm mesial and -0.12 mm distal for the graft group and -0.01 mm mesial and -0.11 mm distal for the nongraft group (P = .07 for mesial and .83 for distal). The OHIP score was significantly reduced at T2 compared to T0 (P = .003) for the entire cohort. Conclusions: Augmentation of the alveolar mucosa on the buccal aspect of single-tooth implants is associated with clinically favorable outcomes. A fully digital workflow has been validated to permit crown delivery on CAD/CAM abutments without implant impressions. [ABSTRACT FROM AUTHOR]

Objective: Periodontal disease is caused by subgingival bacteria that adversely affect the host immune system and create and maintain unmitigated inflammation in gingival and periodontal tissues. The condition is also linked to systemic conditions including cardiovascular disease, diabetes, and arthritis. Periodontitis elevates the bacterial load and spreads systemic inflammation through infection and inflammation. The main radiographic sign of periodontitis is marginal bone loss. Risk factors, including medications, smoking, age, and sex, are known to influence periodontal health. However, there is little information about the impact of systemic conditions and medications on tooth wear. The aim of the present study was to assess the association between systemic conditions and medications and radiographic signs of tooth wear and marginal bone loss. Method and materials: This retrospective analysis was conducted on a group of 2,223 consecutive patients who came for dental treatment in the clinics of a large Health Maintenance Organization in Israel. Data available for the study included details of concomitant systemic diseases and medication and fullmouth radiographic surveys. Odds ratio and logistic regression analysis were used to detect associations between systemic conditions and medication, and marginal bone loss and tooth wear. Results: The results indicated an elevated odds ratio for tooth wear associated with age, sex, and smoking across all age groups. Among young patients, those using proton pump inhibitors and psychiatric medications had an elevated risk of tooth wear. Age, smoking, and diabetes conditions were associated with an increased odds ratio for marginal bone loss in all age groups. Psychiatric medications and sex elevated the odds ratio for marginal bone loss only among older patients. Conclusion: The results highlight the significant impact of age, sex, and smoking on tooth wear, and extend these risks to alveolar bone loss when combined with diabetes and psychiatric conditions. [ABSTRACT FROM AUTHOR]

Diverse surgical approaches, such as resective, reconstructive, and combined therapy, have been proposed for peri-implantitis treatment. A resective surgical approach with an adjunctive modified implantoplasty refers to the modification of the implant body into a constricted area to mimic a "waist" silhouette. This modified technique forms an adequate concave smooth area that may favor the outcomes of resective surgical therapy for soft tissue adaptation, biofilm control, and possible peri-implant bone gain over the long term. The present case series aimed to exhibit the long-term clinical and radiographic outcomes of resective surgery with adjunctive implantoplasty over a 6- to 11-year follow-up. Four patients presenting four implants (one per patient) diagnosed with peri-implantitis (according to an established case definition) were included in the present case series. Patients underwent resective surgery, a modified implantoplasty approach, and implant surface decontamination. After surgical therapy, clinical and radiographic outcomes such as bleeding on probing (BoP), suppuration on probing (SoP), probing depth (PD), marginal recession (MR), modified plaque index (mPI), and marginal bone levels (MBLs) were recorded over a long-term follow-up period. Over the 6- to 11-year follow-up, mean BoP, PD, and SoP scores amounted to 17% ± 24%, 3.2 ± 0.66 mm, and 0%, respectively. Mean BoP, PD, and SoP scores were reduced by 67% ± 24%, 2.5 ± 1.26 mm, and 100%, respectively. Radiographic analysis revealed a mean radiographic bone gain of 3.1 ± 1.84 mm. Peri-implant marginal bone loss surface area decreased by 5.7 ± 3.77 mm2 over the long-term follow-up. Resective therapy with adjunctive implantoplasty promoted favorable clinical and radiographic outcomes at treated peri-implantitis sites over a long-term period. [ABSTRACT FROM AUTHOR]

Surface contaminants on customized implant abutments could trigger an inflammatory response in the peri-implant tissues. The aim of this randomized controlled study was to assess the radiographic bone changes around implants restored with customized, platform-switched abutments, with and without autoclave treatment, 12 months after definitive restoration. Dental implants were placed 1 mm subcrestally in 64 systemically healthy patients (mean age: 63.3 ± 10.0 years; 31 patients had a history of periodontitis) to replace single or multiple missing teeth. According to a randomization list, abutments were subjected to steam and autoclave sterilization (43 implants, test group) or steam cleaning alone (44 implants, control group). Periapical standardized radiographs were taken at implant placement, prosthetic abutment connection, and 12 months after definitive cement-retained restoration. All implants were clinically stable without any sign of infection at the 12-month follow-up. An average marginal bone loss of 0.25 ± 0.19 mm was found in the test group compared to 0.35 ± 0.23 mm in the control group (no statistically significant difference), while the percentage of bleeding sites was significantly higher in the control group (8.7% ± 13.1% vs 19.1% ± 19.8%; P = .035). Autoclave treatment of customized abutments seems to reduce the inflammatory response around subcrestally placed implants. [ABSTRACT FROM AUTHOR]

Purpose: To assess the complications, satisfaction, and quality of life of patients rehabilitated with delayed and immediate loading of single crowns. Materials and Methods: An electronic search was conducted in PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, and Embase databases up to February 2023. Only prospective studies and randomized and nonrandomized clinical trials comparing immediate and delayed loading were included. For the quantitative analysis, dichotomous and consistent variables were evaluated with a 95% confidence interval. Results: A total of 20 studies were evaluated. No statistically significant difference was observed between protocols: satisfaction (I²: 0%; P = .42), quality of life (I²: 0 %; P = .05), biologic complications (I²: 9%; P = .17), mechanical complications (I²: 58%; P = .84), and survival rate (I²: 0%; P = .38). The subgroup analysis showed significant differences only for marginal bone loss (MBL) when immediate implants were placed in the mandible (I²: 15%; P = .01) and posterior zone (I²: 0%; P = .001). Conclusions: Complications and patient-centered outcomes for immediate single-implant crowns were comparable to delayed loading. Scientific evidence showed no significant difference between loading protocols for survival rates. Note that several factors could interfere with the complication events, implant failures, and MBL. The subgroup analysis showed that only immediate implants placed in the posterior mandible had a higher and statistically significant mean MBL. [ABSTRACT FROM AUTHOR]

Purpose: To assess the healing process of the extraction socket and the dimensional changes that occur after alveolar ridge preservation utilizing a polylactide-co-glycolide scaffold (PLGA). Materials and Methods: The present study involved the extraction of 28 teeth from 14 patients. The total number of sockets was 28, which were divided into two groups consisting of 14 test sockets and 14 control sockets. The study group (SG) was subjected to socket preservation with a PLGA scaffold while the control group (CG) was left for spontaneous healing. The dimensions were measured before and after operation at 1, 3, and 5 mm below the alveolar crest horizontally and the height of buccolingual bone vertically. Results: According to the histologic analyses, the PLGA scaffold was resorbed within 4 months. CBCT imaging revealed a decrease in the horizontal crest dimension at three distinct coronoapical levels in SG, measuring 2.05 ± 1.05 mm at -1 mm, 1.51 ± 0.89 mm at -3 mm, and 0.92 ± 0.7 mm at -5 mm. CG showed readings of 1.22 ± 1 at -1 mm, 0.92 ± 0.67 at -3 mm, and 0.73 ± 0.69 at -5 mm. In comparison to CG, SG showed a significant reduction in horizontal losses at -1 mm. Vertical crest dimensions decreased by 1.64 ± 1.11 mm for the buccal bone height and by 1.56 ± 1.08 mm for lingual bone height in SG; in CG, the buccal and lingual bone height had mean values of 2.08 ± 1.44 mm and 1.73 ± 1.27 mm, respectively. There was no statistically significant difference observed in the vertical losses between the groups. Conclusions: Following a period of 4 months, the PLGA scaffold was completely resorbed. Based on CBCT measurements, horizontal resorption was lower than CG at -1 mm coronally. [ABSTRACT FROM AUTHOR]

Objectives: This systematic review compares the impact of ball and locator attachments on marginal bone loss in implant-retained overdentures in completely edentulous patients. Method and materials: Following PRISMA guidelines, health science librarians completed literature searches from inception to 17 March 2023 in seven databases. There were 15,686 items exported to EndNote from Embase.com, CINAHL (EBSCO), Cochrane Library, Ovid MEDLINE-ALL, PubMed, Scopus, and Web of Science. Hand-searching added four more articles. After deduplication, 6,756 items were screened for eligibility. Twenty-nine studies were assessed by full text, of which ten studies, involving 424 subjects, were included in the review. Risk of bias assessment was conducted using the Cochrane risk-of-bias tool and the Newcastle-Ottawa scale. A meta-analysis was performed to synthesize and analyze the collective data from the selected studies. Results: The included studies used diverse methodologies, implant systems, and loading protocols. Most studies reported no significant difference in marginal bone loss between ball and locator attachments. The meta-analysis revealed high heterogeneity. Conclusion: The results of this systematic review suggest that ball and locator attachments exhibit similar performance in terms of marginal bone loss in implant-retained overdentures. However, the limited number, risk of bias, and heterogeneity of studies highlight the need for standardized research designs and larger sample sizes in future investigations to draw more definitive conclusions. [ABSTRACT FROM AUTHOR]

The management of marked horizontal bone atrophy represents a critical challenge for traditional implantology procedures. For this purpose, clinicians have developed several protocols and procedures to allow the most suitable and accurate surgical and prosthetic implant rehabilitation. Despite the development of guided bone regeneration methods and the use of small-diameter implants, the rehabilitation of thin bone areas is a clinical dilemma for the medium- and long-term survival of implant-prosthetic therapies. This clinical case evaluates the use of wedge-shaped implants for the full-arch rehabilitation of an atrophic maxilla with a thin ridge. This treatment choice allowed a minimally invasive rehabilitation, avoiding regenerative bone surgery, while respecting biologic and prosthetic limits. Furthermore, evaluation of the implant stability quotient and marginal bone loss values during the first year of follow-up allowed analysis of the behavior of this rehabilitation in fullarch maxillary cases. [ABSTRACT FROM AUTHOR]

This study assessed the effects of buccal contour augmentation for periodontally compromised teeth with horizontal bone loss. A total of 30 subjects were divided into Group A or Group B (n = 15 subjects per group). Group A received open-flap debridement (OFD) with buccal contour augmentation using deproteinized bovine bone mineral (DBBM), jointly referred to as contour augmentation for periodontal defects (CAPD; test group). Group B received only OFD (control group). Bleeding on probing (BOP), clinical attachment level (CAL), probing depth (PD), gingival recession (GR), keratinized mucosa width (WKM), keratinized mucosa thickness (TKM), and labial cortical plate thickness were compared at baseline and 1 year. BOP, CAL, PD, and GR did not show significant differences. TKM increased by 1.76 mm for Group A but decreased by 1 mm for Group B. WKM increased from 2.86 ± 0.4 mm to 3.6 ± 0.71 mm (P < .001) and from 2.93 ± 0.32 mm to 3 ± 0.7 mm (P = 0.5) for Groups A and B, respectively, which showed statistical significance. Labial cortical plate thickness increased from 0.94 ± 0.3 mm to 1.95 ± 0.54 mm (P < .001) for Group A but decreased from 0.87 ± 0.45 mm to 0.68 ± 0.31 mm for Group B. Visual analog scale scores for pain perception showed no difference between the two groups. CAPD for periodontally compromised teeth improves WKM and TKM. Long-term analyses are needed to determine its benefits in daily clinical practice. [ABSTRACT FROM AUTHOR]

Bone graft materials are often used in implant treatment to optimize functional and esthetic outcomes. The requirements for bone grafting materials are the ability to maintain space for bone regeneration to occur and the capability of being resorbed by osteoclasts and replaced with new bone tissue occurring in passive chemolysis and bone remodeling. Carbonate apatite (CO3Ap) granules (Cytrans Granules, GC) are a chemically synthetic bone graft material similar to autogenous bone minerals and more biocompatible than allografts and xenografts. The aim of this report is to evaluate the efficacy of CO3Ap granules in implant treatments when used alone or in combination with autogenous bone. The clinical findings and the radiographic and histologic assessments in three cases of immediate implant placement and lateral and vertical guided bone regeneration are reported. Despite the short-term follow-ups, histologic findings showed that CO3Ap granules were efficiently resorbed and replaced bone in clinical use. Furthermore, the clinical findings showed that CO3Ap granules maintained their morphology around the implant. This limited short-term case report suggests that this bone substitute is effective. However, further clinical studies and long-term reports of this new biomaterial are needed. [ABSTRACT FROM AUTHOR]

Purpose: To determine the relationship between bone loss that occurs during the peri-implantitis process and variations in implant stability using resonance frequency analysis (RFA) measurement methods. Materials and Methods: Forty selftapping implants were placed in cow ribs, and study scenarios were established according to the affected implant side and bone loss depth (n = 10 implants per group): Case 1 = bone loss on one side (vestibular); Case 2 = bone loss on two opposite sides (buccal and lingual); Case 3 = bone loss on two adjacent sides (buccal and mesial); and Case 4 = foursided bone loss (circumferential). For each group of 10 implants, first a bone loss of 0 mm was evaluated, then 4-mm defects (simulating 1/3 of bone loss) were created and evaluated, and finally 8-mm defects (simulating 2/3 of bone loss) were created and evaluated. Osteotomy measurements were made with a periodontal probe. For each implant, RFA was measured by the same operator using the Beacon system (Osstell). Results: The initial implant stability quotient (ISQ) values of the 40 implants exceeded 70, reflecting an average of 73 in the buccolingual (VL) and 74.8 in the mesiodistal (MD) directions. ISQ measurements in the 10 implants in which bone dehiscence was performed on the vestibular aspect reflected a decrease in ISQ values as bone loss increased. When generating bone loss in two opposite sides (buccal and lingual), a greater decrease in ISQ values was observed when 2/3 of the implant were affected. The average VL ISQ measurement was less than 70 when at sites with 2/3 of bone loss. Conclusions: When bone loss occurs on only one side of the implant, the ISQ values decrease, but the implant maintains good stability. The same occurs when two opposite sides of the implant are affected, as the unaffected side has the least decrease in ISQ value. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of interleukin-6 (IL-6) inhibitor (tocilizumab) on bacterial infection-associated bone resorption around implants during osseointegration in rabbits. Materials and Methods: At total of 24 male, 9-monthold New Zealand white rabbits were included, and their two mandibular anterior teeth were extracted. Three months after extraction, 24 one-piece Dentium implants (Ø 2.5 mm, intraosseous length of 12 mm) were inserted in the anterior mandible, and the rabbits were divided into four groups (n = 6 per group). Different treatment methods were used in each group: blank control group (BC); only silk ligation (negative control [NC]); silk ligation and injection with minocycline hydrochloride ointment (positive control [PC]); and silk ligation and injection with tocilizumab at 8 mg/kg via the auricle vein (experimental [EP]). Eight weeks later, the animals were sacrificed, and samples were collected and then analyzed using microcomputed tomography (microCT) scanning, immunohistochemical analysis, and histologic analysis. Results: From the microCT measurement, the ratio of the bone volume to the total volume (BV/TV) in the EP group was 67.00% ± 2.72%, which was higher than that in the other three groups (58.85% ± 2.43% in the BC group, 55.72% ± 2.48% in the PC group, and 36.52% ± 3.02% in the NC group). From immunohistochemical analysis, the expression of IL-6 was found to be higher in the NC group than in the BC, PC, and EP groups, but there was no statistical difference between these three groups. Furthermore, the RANKL (receptor activator of nuclear factor-κB ligand) expression was the lowest in the EP group, followed by the BC group, the PC group, and the NC group, which had the highest expression; there was no difference between the NC and PC groups. Upon histologic analysis, significant new bone was found on the implant surfaces in the EP group, sparse and less new bone could be seen in the BC and PC groups, and the most serious bone resorption occurred in the NC group. Conclusions: Tocilizumab, an inhibitor of IL-6, has a certain effect in preventing bone loss around implants caused by bacterial infection during the osseointegration period. [ABSTRACT FROM AUTHOR]

Purpose: This prospective study evaluated the marginal bone level and periodontal parameters 6 years after placement of a convergent transmucosal neck implant. Materials and Methods: In total, 71 implants were placed in 60 patients. Of these, 52 implants were placed with a flapless technique and with the convergent neck exposed by 1 mm (early and delayed placement), while 19 implants were placed immediately after extraction (immediate placement). At least 3 months after insertion, customized abutments were applied and provisional resin crowns were cemented, while being careful to prevent any tissue compression. After 3 weeks, definitive metal-ceramic crowns were designed with the finish line at the soft tissue level and free from any compression. The implant survival rate at 6 years, marginal bone level changes (ΔMBL, mm), and Pink Esthetic Score (PES) were evaluated. Gingival phenotype was determined before the implant surgeries (thin/thick). A three-level hierarchical model was examined with a random intercept and random slope on follow-up time at the patient level and a random intercept at the implant level. Results: In all, 57 patients with 67 implants reached the 6-year point; 3 patients (5.0%) dropped out. The implant survival rate was 100%. ΔMBL from baseline to 24 months was 0.58 mm (95% CI: 0.48, 0.68), while ΔMBL from 24 to 72 months was 0.33 mm (95% CI: 0.19, 0.47). PES improved steadily from 6 to 48 months (+0.96; 95% CI: 0.71, 1.20), with overall stability at 72 months. No correlation between MBL and PES was observed. A significant association was found between thick gingival phenotype and less MBL variation. Greater implant diameter offered more MBL stability after 3 years but resulted in lower PES values. Conclusions: The use of convergent transmucosal neck implants placed with a flapless transmucosal approach with the crown margin positioned at the gingival level preserved marginal bone and guided gingival morphology for up to 72 months. The gingival phenotype was the parameter that most affected the soft and hard tissues. In the long term, implant placement timing was not related to MBL. [ABSTRACT FROM AUTHOR]

Purpose: The structural and compositional similarities between dentin and alveolar bone form the basis for utilizing dentin for bone regeneration. Various authors have recommended using treated mineralized, partially demineralized, or demineralized dentin grafts instead of xenografts because of their comparable clinical and radiographic results and lower costs. The current study therefore compared the effect of untreated mineralized dentin grafts (UMDGs) versus xenografts in vertical and horizontal augmentation around dental implants that were immediately placed in the mandibular anterior region. Materials and Methods: A total of 56 patients who required immediate dental implant placement in the mandibular anterior region were randomly allocated to group I (study), where ground dentin was washed with normal saline and placed around the dental implants, or group II (control), where a xenograft was used. The primary implant stability was measured at the time of implant placement. Secondary implant stability, plaque index (PI), bleeding index (BI), probing depth (PD), and keratinized mucosa width (KMW) were assessed at baseline (time of definitive abutment and provisional crown placement) and then at 3, 6, and 12 months. Pain and the number of analgesics consumed were assessed daily during the first postoperative week. Marginal bone loss (MBL) and radiodensity were assessed radiographically. Results: There were no significant differences between the groups in terms of postoperative pain, the number of analgesic tablets consumed, peri-implant mucositis, or peri-implantitis. Both groups showed comparable results for the PI, BI, and PD. Moreover, there was no statistical difference between the groups with regard to primary implant stability and secondary implant stability at baseline and 12 months. Group I showed significantly lower secondary implant stability after loading at 3 and 6 months and significantly greater bone loss and lower bone density before exposure. KMW and MBL after exposure were significantly higher in group I at all time points. Conclusions: Although UMDGs showed similar clinical results to xenografts, including primary and secondary implant stability, they had higher resorption rates than xenografts. Therefore, treatment of the dentin graft is required. Thus, the authors do not recommend using UMDGs. [ABSTRACT FROM AUTHOR]

Purpose: To answer the following focus question: In preclinical in vivo experimental models, do oral implants placed in overdimensioned (OD) sites present greater biomechanical properties and histomorphometric parameters of osseointegration compared to implants placed in standard or undersized implant sockets? Materials and Methods: Online databases were searched for controlled animal studies reporting on OD sites up to February 2023. The relative implant-final drill discrepancy (IDD) was used to categorize the control and test groups according to surgical drilling protocol: (1) control: undersized (IDD > 0.5 mm) or standard (IDD = 0.2 to 0.5 mm); and (2) test OD: stress-free oversized (IDD = 0.0 to -0.1 mm); test GAP: friction-free oversized (IDD = -0.1 mm). Random-effects meta-analyses were performed for the outcomes of insertion and removal torque values (ITV and RTV, respectively), bone-to-implant contact (%BIC), and bone density (%BD) for short- (0 to 2 weeks), intermediate- (3 to 4 weeks), and long-term (= 5 weeks) healing periods. Results: Of the 527 records identified, 13 studies met the eligibility criteria. Histologically, the OD and GAP groups prevented ischemic necrosis and extensive bone resorption at the bone-implant interface in both the marginal cortical layer and the trabeculae. Faster and increased rates of bone formation, characterized by primary osteons and highly vascularized tissue, took place in OD sites between 1 and 5 weeks of healing. Meta-analyses indicated statistically significant benefits in favor of (1) control vs OD for short-term healing in extraoral sites, with pooled estimates (weighted mean difference) of ITV = 25.35 Ncm, %BIC = 2.10%, and %BD = 26.19%; (2) control vs OD for long-term healing in intraoral sites, with %BD = 11.69%; (3) control vs GAP for intermediate-term healing in extraoral sites, with %BD = 3.03%; and (4) control vs GAP for long-term healing in extraoral sites, with RTV = 5.57 Ncm. Conclusions: Oversized surgical preparation of the implant site does not seem to provide any additional benefit compared to standard or undersized sites regarding quantitative parameters of osseointegration. However, it does minimize marginal bone resorption and yields better-quality bone healing, despite the comparable results among different experimental animal models in the late postoperative period. [ABSTRACT FROM AUTHOR]

Objective: This retrospective study analyzed radiographic bone levels of 10,871 dental implants in a cohort of 4,247 patients over a 22-year period. The objectives of the study were to assess and explore risk factors associated with the radiographic bone level of dental implants. Method and materials: A longitudinal observational cohort study based on data collected from 1995 to 2019 was conducted on implants placed by a single periodontist. Inclusion criteria included both partially and fully edentulous sites. Exclusion criteria were patients who were considered ASA 3 or greater. Information on medical and dental status prior to implant placement such as diabetes and smoking were included in the analysis. Implant factors such as the implant characteristics (length and diameter) and surgical site were recorded. The outcome assessed was the prevalence of bone loss around implants and any associative factors related to the bone loss. Results: Overall, dental implants lost an average of 0.05 ± 0.38 mm of bone 2 to 3 years after placement and 0.21 ± 0.64 mm 8 years after placement. The soft tissue condition was evaluated using the Implant Mucosal Index (IMI), and bone loss around dental implants was significantly higher when bleeding on probing was multi-point and moderate, multi-point and profuse, and when infection with suppuration was recorded. The mean difference in bone level between smokers and nonsmokers was 0.26 mm (P < .01) over a 4-year period. A mean difference of 0.10 mm (P = .04) in bone loss over 4 years was found between those with an autoimmune disease compared to those without. The diameter of the implant and immediate loading of the dental implant did not influence the radiographic bone levels over time. Conclusions: This large dataset of dental implants highlights predictive risk factors for bone loss around dental implants and the impact these risk factors have on the implant bone level. Consideration of these risk factors by both the dental team and the patient prior to dental implant placement will promote success of the treatment. [ABSTRACT FROM AUTHOR]

This retrospective study evaluated the clinical outcomes of surgical crown reattachment in the treatment of complicated crown-root fractures in permanent teeth in 35 patients. Treatments were defined as follows: surgical crown reattachment combined with internal fixation with a fiber-reinforced core post, ostectomy, and reattachment of the original crown fragment. Patients were examined to record the periodontal pocket depth (PD), marginal bone loss, tooth migration, and coronal fragment looseness or loss. In most cases, the fracture lines on the palatal aspect were located below the alveolar crest. About 20% to 30% of teeth had periodontal pockets ≥ 3 mm present at least 1 year after surgery. Significant PD differences were observed between the traumatized teeth and adjacent untraumatized teeth at 6 months. The available evidence suggests that surgical crown reattachment is a feasible and effective technique for managing complicated crown-root fractures in permanent teeth. [ABSTRACT FROM AUTHOR]

Purpose: To retrospectively determine the cumulative survival rate (CSR) and marginal bone level change (ΔMBL) around novel hybrid design tissue-level (TL) dental implants that support multiple-screw-retained restorations. Materials and Methods: Implant CSRs were analyzed at the implant and patient level using Kaplan-Meier estimates. ΔMBL was measured by comparing the periapical loading and follow-up visit radiographs using an improved standardized digital methodology based on image gray levels. ΔMBL outcomes were subject to linear mixed regression to identify potential risk factors. Results: A total of 301 TL implants in 69 patients with an average age of 62.6 ± 11.7 years (range: 36 to 87 years) at the time of implant placement were considered for the analysis. All 301 implants were successfully restored and loaded. The 54-month CSRs at the implant and patient levels were 98.9% (95% CI: 96.7 to 99.6) and 95.3% (95% CI: 86.1 to 98.5), respectively. ΔMBL after a mean follow-up of 22 ± 10.7 months after loading was 0.00 ± 0.57 mm. None of the implant sites showed marginal bone loss exceeding 1.5 mm. Multivariate regression analysis revealed a significant association between ΔMBL and the loading protocol (P = .027) but not between ΔMBL and age or transgingival height. Conclusions: The high CSRs and stable peri-implant marginal bone levels support the use of recent TL implants, which have a hybrid design inherited from the bone-level implant-abutment connection, as a suitable treatment option for restoring partially or fully edentulous patients with a good mid-term prognosis. These results should be complemented by further prospective studies in a real-world multicenter private practice setup that represents the daily realities of implant treatment. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the soft tissue response to the placement of additively manufactured subperiosteal jaw implants (AMSJI) in the severely atrophic maxilla and to identify possible risk factors for soft tissue breakdown. Materials and Methods: An international multicenter study was conducted, and 15 men (mean age: 64.62 years; SD: ± 6.75) and 25 women (mean age: 65.24 years; SD: ± 6.77) with advanced maxillary jaw resorption (Cawood and Howell Class V or more) were included in this study. General patient data were collected, and all subjects were clinically examined. Inclusion criteria were patients who underwent bilateral AMSJI placement in the maxilla at least 1 year prior. Exclusion criteria were patients who did not have patient, surgeon, or dentist consent to participate in the study before their inclusion. Results: A total of 40 patients were enrolled, with a mean follow-up period of 917 days (SD: ± 306.89 days). Primary implant stability was achieved postoperatively in all cases, and all implants were loaded with a final prosthesis. At the time of the study, only 1 patient showed mobility (> 1 mm) of the bilateral AMSJI. Due to mucosal recession, exposure of the framework was seen in 26 patients (65%) and was mainly in the left (21.43% of 26) and right (18.57% of 26) midlateral region. A thin biotype and the presence of mucositis were found to be risk factors (P < .05). Although not significant, smokers had a risk of developing a recession that was nearly seven times (odds ratio: 6.88; P = .08) greater than that of nonsmokers. Conclusions: Twenty-six (65%) patients presented with a recession in one (or more) of the seven regions after oral rehabilitation with bilateral AMSJI placement. Several risk drivers were evaluated. The collapse of soft tissues around the AMSJI that led to caudal exposure of the arms was correlated with a thin biotype and the presence of mucositis. [ABSTRACT FROM AUTHOR]