Bone preservation or augmentation simultaneous with or prior to dental implant placement: A systematic review of outcomes and outcome measures used in clinical trials in the last 10 years

Dental Implant Survival Rates: Comprehensive Insights from a Large-Scale Electronic Dental Registry

BACKGROUND

This descriptive study aimed to assess the survival rates and outcomes of dental implants in one of the four national HMOs in Israel. Data are provided for the period from 1 January 2014 to 31 December 2022.

MATERIALS AND METHODS

This retrospective analysis utilized electronic medical records of patients who underwent dental implant placement during the specified period. Statistical analyses included chi-squared tests, Student's t-tests, and generalized estimating equation (GEE) analyses to identify potential risk factors associated with early and late implant failures.

RESULTS

A total of 158,824 dental implants were placed in 53,874 patients. The overall implant failure rate was 2.21%, while the early failure rate during the osseointegration phase-before prosthetic reconstruction-was 1.56%. Significant associations with implant failure were observed for male patients (2.53% failure rate), implants in the maxillary molar region (3%), and the central incisor region (3.37%), approximately double the failure rates seen in other implant sites (p < 0.001).

CONCLUSIONS

This extensive data analysis demonstrates a low overall failure rate for dental implants. The highest failure incidence occurred within the first year post-implantation, declining in subsequent years irrespective of rehabilitation status. Early failure risk factors differ based on various factors and should be carefully integrated into presurgical planning.

Patient-Reported Outcome Measures Following Implant Placement With Simultaneous Horizontal Bone Augmentation

OBJECTIVES

This study aimed to evaluate the impact of implant placement with simultaneous bone augmentation on patients' willingness to repeat the procedure. Secondary outcomes included assessing patient-reported outcome measures, clinical- and surgical-related factors affecting treatment outcomes.

METHODS

Subjects who were currently undergoing or have undergone implant placement with simultaneous bone augmentation in the esthetic region (maxillary second premolar to second premolar) were assigned to three groups: Group A (short-term), Group B (1-5 years post-surgery), and Group C (> 5 years post-surgery). Clinical assessments, dichotomous questions, and visual analogue scales were used to evaluate therapeutic outcomes according to the group of interest.

RESULTS

One hundred and fifty patients completed the study (n = 50 per group). In Group A, 16% experienced wound dehiscence (membrane exposure < 3 mm), and 2% had postoperative bleeding, infection, swelling, or abscess. Flaps extending beyond three teeth significantly increased early membrane exposure (p = 0.04). Patient-reported postoperative discomfort (p < 0.001) and wound healing scores (p < 0.04) decreased over time. Willingness to repeat the procedure was 100%, 88%, and 98% in Groups A, B, and C, respectively, with satisfaction rates of 98.2 ± 7.5, 91.2 ± 10.6, and 95.2 ± 10.9. No significant differences were found between Groups B and C for functional or esthetic satisfaction. However, Group C reported higher satisfaction and comfort (p < 0.001). Younger adults and women reported greater postoperative discomfort than older adults and men.

CONCLUSIONS

Implant placement with simultaneous horizontal bone augmentation in esthetic areas shows a high willingness of patients to repeat the procedure in the short-, mid-, and long-term. Additionally, this therapeutic approach yields low rates of postoperative complications and discomfort, along with high patient satisfaction related to functional performance, esthetics, and overall comfort.

Learn, unlearn, and relearn post-extraction alveolar socket healing: Evolving knowledge and practices

OBJECTIVE

This review was to offer a comprehensive analysis of currently available evidence on post-extraction alveolar socket healing, including i) the histological and molecular events during alveolar socket healing, ii) the dimensional ridge alterations after socket healing and controversies relating to sinus pneumatisation, iii) the patient-specific factors, procedural elements, and site-related variables influencing socket healing, iv) techniques and effectiveness of alveolar ridge preservation (ARP) procedure, and v) the philosophies and cost-effectiveness of ARP in clinical practice.

SOURCES AND STUDY SELECTION

To investigate the dimensional profiles of the alveolar ridge following unassisted healing, an overview of systematic reviews was conducted in February 2024 by two independent reviewers. Four electronic databases were searched in Pubmed, Embase, Web of science and Cochrane Library between 2004 and 2024 to identify all relevant systematic reviews on post-extraction healing. A further manual search of reviews was also conducted. The articles were further reviewed in full text for relevance. The AMSTAR-2 appraisal tool was adopted to assess methodological quality. Current research pertaining to other listed objectives was objectively analysed in narration.

DATA

11 out of 459 retrieved studies were selected and ultimately covered in this review on the dimensional changes of alveolar ridge following natural healing: Seven systematic reviews and four systematic reviews with meta-analyses. The methodological quality of all included reviews was critically low.

CONCLUSION

This review thoroughly examines the healing profiles of post-extraction alveolar sockets and highlights the dynamic process with overlapping phases and the inter-individual variability in outcomes. ARP procedure is a potential strategy for facilitating prosthetic site development, while the current evidence is limited. Herein, an individualised and prosthetically driven approach is crucial. Further well sized and designed trials with novel biomaterials need to be undertaken, and the role of artificial intelligence in predicting healing and assisting clinical decision-making could be explored.

CLINICAL SIGNIFICANCE

By advancing our understanding of alveolar socket healing and its management strategies, clinicians can make more informed decisions regarding patient and site level assessment and selection, surgical techniques, and biomaterial choices, ultimately contributing to the enhanced healing process with reduced complications and improved quality of life for patients undergoing tooth extraction and dental implant treatments.

One-piece versus two-piece zirconia abutment supported single implant crown in the esthetic region: 3-Year results from a split-mouth randomized controlled clinical trial

OBJECTIVES

To compare the clinical, radiographic, and immunological outcomes between one-piece versus two-piece zirconia abutments supported single implant crowns in the esthetic region.

MATERIALS AND METHODS

The study followed a split-mouth, double-blind, and randomized controlled clinical design for a duration of 3 years. Twenty-two eligible patients with 44 implants were randomly assigned to two groups: Group 1 (one-piece zirconia abutment with zirconia base, n = 22) and Group 2 (two-piece zirconia abutment with titanium base, n = 22). The primary outcome was the technical complication rate. Additionally, survival rates, cytokines concentrations in peri-implant crevicular fluid (PICF), peri-implant conditions, marginal bone loss, and pink/white esthetics score (PES/WES) were assessed as secondary outcomes.

RESULTS

Twelve of 22 patients attended the 1-year follow-up (due to the COVID pandemic), and 19 patients attended the 3-year examination. Two abutments in Group 1 were fractured after 10 and 12 months in function. Additionally, one screw loosening occurred in Group 1 at 1-year follow-up. The 3-year technical complication rate was significantly higher in Group 1 than that in Group 2 (15.79% vs. 0%, p < .001). The 3-year implant survival rate was 100% in both groups. The concentration of IFN-γ in PICF was significantly upregulated in Group 2 (p = .018). Furthermore, the IL-6 concentration was positively correlated with BOP% (p = .020).

CONCLUSIONS

Two-piece zirconia abutments exhibited superior technical performance compared to one-piece designs during a 3-year follow-up in the anterior region. However, further long-term research is necessary to verify the immunological stability of two-piece zirconia abutments.

Full block or split block?-Comparison of two different autogenous block grafting techniques for alveolar ridge reconstruction

OBJECTIVE

To evaluate radiographic bone gain after alveolar ridge augmentation with two different designs of autogenous block graft harvested from the mandible.

MATERIALS AND METHODS

Alveolar ridge defects were evaluated by preoperative cone beam computed tomography (CBCT) and grafted in a staged approach using intraoral block grafts. The ridge augmentation was either performed using the full-block technique (group 1) or the split-block technique (cortical plate with autogenous bone chips) (group 2). After 4 months of bone healing, a further CBCT scan was performed before implant placement. Horizontal and vertical bone gain were measured.

RESULTS

In this retrospective study, 91 patients were grafted with block grafts (36 patients with full-block grafts; 55 patients with split-block grafts) resulting in 171 block grafts in total. The mean horizontal bone gain was 3.37 ± 0.71 mm in group 1 and 5.79 ± 2.20 mm in group 2. A linear mixed-effect model also showed a statistically significant group difference (p < 0.001, estimate: 3.455, 95% CI: [2.082-4.829]). The mean vertical bone gain was 2.85 ± 0.73 mm in group 1 and 7.60 ± 1.87 mm in group 2. A linear mixed-effect model also showed a statistically significant group difference (p: 0.029, estimate: 3.126, 95% CI: [0.718-5.557]). Mean marginal bone level was 0.33 ± 0.37 mm (group 1) and 0.17 ± 0.29 mm (group 2).

CONCLUSION

The split-block technique resulted in a greater bone gain than the full-block technique. This effect was observed in both the vertical and the horizontal dimensions.

Early tissue and healing responses after maxillary sinus augmentation using horizontal platelet rich fibrin bone blocks

BACKGROUND

The effects of horizontal platelet-rich fibrin (H-PRF) bone block on the healing and immune response during sinus augmentation have not been fully investigated histologically at early time points.

METHODS

Eighteenth male New Zealand white rabbits underwent bilateral sinus augmentation and were divided into two groups: deproteinized bovine bone mineral (DBBM) alone and H-PRF + DBBM (H-PRF bone block) group. Maxilla samples were collected at 3, 7 and 14 days post sinus augmentation procedures and analyzed using histological staining for the number of inflammatory cells, new blood vessels and evidence for early osteoclast bone turnover/remodeling. Furthermore, the effects of H-PRF bone blocks on the migration of osteoblasts and THP-1 macrophages were evaluated using a Transwell assay in vitro.

RESULTS

A higher number of immune cells were found in the H-PRF bone block group at 3 and 7 days post-surgery when compared to the DBBM alone group,most notably in the regions close to the mucosal lining and bone plates. Furthermore, a significantly greater number of new blood vessel formations and early signs of osteoclast development were found in the H-PRF bone block group at 14 days. The in vitro transwell assay further confirmed that culture medium from H-PRF bone block markedly promote the migration of osteoblasts and THP-1 macrophages.

CONCLUSIONS

The findings from this study have shown that H-PRF bone block is capable of increasing early immune cell infiltration leading to the acceleration of neovascularization and speeding the process of bone metabolism in vivo following maxillary sinus grafting with DBBM.

Buccal bone thickness and mid-facial soft tissue recession after various surgical approaches for immediate implant placement: A systematic review and network meta-analysis of controlled trials

AIM

To evaluate the relative efficacy and confidence in the precision of the results of different surgical interventions for immediate implant placement in the anterior area.

MATERIALS AND METHODS

Electronic searches were performed in PubMed, Embase, and Cochrane CENTRAL. Randomized controlled trials comparing different surgical techniques in anterior jaws for type 1 implant placement were included. Outcome measures included implant survival (primary outcome), buccal bone thickness (BBT) reduction, and mid-facial soft tissue recession (MSTR). Risks of bias assessment, network meta-analysis (NMA), sensitivity analysis, and quality-of-evidence assessment were performed.

RESULTS

Twenty-two studies reporting on 948 subjects and 5 surgical interventions were included. Fourteen early failures were reported. Compared with open-flap surgery without tissue augmentation (F-N) and looking at BBT preservation, NMA showed that there was moderate confidence that flapless surgery with hard tissue augmentation (FL-HTA) was better than flapless surgery without tissue augmentation (FL-N) or open-flap surgery with hard tissue augmentation (F-HTA) (mean difference -0.8 mm, 95% confidence interval: -1.1 to -0.5 mm; -0.6 mm, -0.9 to -0.4 mm; and -0.5 mm, -0.7 to -0.3 mm, respectively). There was moderate confidence that flapless surgery with hard and soft tissue augmentation (FL-HTA&STA) could significantly prevent MSTR compared with FL-HTA (-0.5 mm, -0.7 to -0.3 mm) and FL-N (-0.6 mm, -1.2 to -0.04 mm). However, there was no significant additional benefit in BBT with the FL-HTA&STA approach compared to the FL-HTA approach (-0.30 mm, -0.81 to 0.21 mm).

CONCLUSIONS

For immediate implant placement in the anterior areas, the FL-HTA approach better preserves BBT (moderate confidence); adding STA improves the stability of the mid-facial soft tissue level (moderate confidence) but at the expense of BBT (low confidence).