The Use of Tissue Grafts Associated with Immediate Implant Placement to Achieve Better Peri-Implant Stability and Efficacy: A Systematic Review and Meta-Analysis.

Background: The goal of this systematic study and meta-analysis was to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants on healing and treatment outcomes. The primary outcomes studied were implant survival rate, pocket depth, marginal peri-implant recession, bone loss, bone thickness (volumetric change), interproximal bone level, mesial and distal papilla migration, and radiographic evaluation; and the secondary parameters were Pink Esthetic Score (PES), vertical distance from implant shoulder and bone, Visual Analogue Score (VAS), Implant Stability Quotient (ISQ), and biological complications (fistulas, pain, mucositis, and peri-implantitis). Methods: The PICO strategy was used to formulate the hypothesis under study: "For patients who underwent extraction and immediate implant placement, what is the efficacy of using any type of graft (bone or soft tissue) compared to non-grafting regarding the peri-implant parameters?" The electronic search process was performed on the MedLine/PubMed and Cochrane databases. It included randomized controlled trials (RCTs) from the last 11 years (from 2012 to November 2023), which were identified and analyzed. Results: Nine RCTs (κ = 0.98) were selected (403 patients and 425 implants); they were divided into three groups: bone graft (75 patients and 75 implants inserted), bone graft and membrane (213 patients and 235 implants inserted), and without bone graft (115 patients and 115 implants inserted). Three studies calculated the mid-facial mucosa level and two reported better results when a connective tissue graft was combined with the xenograft, whereas another study found better results in the combination of a dual-zone technique with a xenograft. Three studies evaluated the total Pink Esthetic Score (PES) at 12 months, where the authors found no significant difference in using a xenogeneic graft with or without a membrane. In the same period, the facial bone thickness was assessed in two articles; the authors reported better results in graft-treated and flapless groups. The risk-of-bias assessment found four studies with low risk, four with moderate risk, and one with a high risk of bias. The meta-analysis showed a medium level of heterogeneity for the mid-facial mucosa level analysis (I2 = 46%) and an overall effect size of 0.79 (95% CI [0.18; 1.40]), a statistically significant results (p = 0.01), with a tendency to favor the experimental group. Also, there was a medium level of heterogeneity among studies regarding total PES (I2 = 45%), with no significant differences between studies (p = 0.91). Homogeneous results (I2 = 0%) were found among studies analyzing facial bone thickness, favoring the experimental group; the forest plot showed an effect of 0.37 (95% CI [0.25; 0.50]), which was statistically significant (p < 0.00001) for this parameter. Conclusions: Then, it was possible to conclude that using bone and soft tissue grafting techniques associated with immediate implant placement (IIP), even though they are not fundamental, was a valuable resource to prevent significant tissue reduction, reaching greater bone stability and higher levels in the Pink Esthetic Score (PES) and Visual Analogue Score (VAS).

Aesthetic and radiographic outcomes using the root membrane technique in immediate adjacent implant placement: A retrospective clinical study with a 5- to 9-year follow-up.

PURPOSE: The root membrane technique was designed to preserve the buccal portion of the root in situ, preventing postextraction bundle bone loss and overlying soft tissue recession. Nevertheless, maintenance of the aesthetic gingival architecture around two or multiple adjacent implants, particularly in the anterior maxilla, remains a challenge, notably regarding the gingival contour and the interimplant papillae. The present study aimed to evaluate the clinical, aesthetic and radiographic outcomes for immediate adjacent implants placed using the root membrane technique in the anterior maxilla in a sample with a 5- to 9-year follow-up. MATERIALS AND METHODS: A retrospective clinical study was designed using the medical records of two private dental practices. A total of 40 patients who were treated using the root membrane technique for at least two adjacent implants and single-crown restorations between January 2010 and February 2019 were selected (100 implants). The clinical and radiographic data were analysed to assess implant survival/success, marginal bone loss and the pink aesthetic score. RESULTS: The cumulative survival rate after a mean follow-up period of 81.5 ± 30.5 months was 99.0% (implant-based) and 97.5% (patient-based), respectively. Between 1 and 5 years (n = 99), the mean marginal bone loss changed from 0.39 ± 0.07 mm to 0.36 ± 0.07 mm and subsequently to 0.37 ± 0.07 mm at the 7-year follow-up (n = 71) and 0.33 ± 0.07 mm at the 9-year follow-up (n = 14). The improvement from 1 year was significant at all the follow-up time points (P = 0.000). The mean global pink aesthetic score increased from baseline (11.33 ± 1.03) to 3 months after placement of the final restoration (11.73 ± 0.95) and the final observation (12.01 ± 0.87). This was a significant increase (P = 0.000 baseline to 3 months, 3 months to final observation and baseline to final observation). CONCLUSIONS: In this non-controlled retrospective study, adjacent implants placed using the root membrane technique achieved a satisfactory survival and success rate. The variation in marginal bone loss showed a significant positive trend from 1 year to 5 and 7 years. The overall pink aesthetic scores improved significantly between sequential observation periods. CONFLICT-OF-INTEREST STATEMENT: Dr Leitão-Almeida receives personal fees (for sponsored lectures) and non-financial support from MegaGen (Daegu, South Korea) outside of the submitted work; the other authors declare no conflicts of interests relating to this study.

Effect of crown to implant ratio and implantoplasty on the fracture resistance of narrow dental implants with marginal bone loss: an in vitro study.

BACKGROUND: Peri-implantitis is a biological complication that affects soft and hard tissues around dental implants. Implantoplasty (IP) polishes the exposed implant surface, to decontaminate it and make it less prone to bacterial colonization. This study investigates whether a higher clinical crown-to-implant-ratio (CIR) reduces implant fracture resistance and whether implants are more fracture-prone after IP in the presence of 50% of bone loss. METHODS: Forty-eight narrow platform (3.5 mm) 15 mm long titanium dental implants with a rough surface and hexagonal external connection were placed in standardized bone-like resin casts leaving 7.5 mm exposed. Half were selected for IP. The IP and control groups were each divided into 3 subgroups with different clinical CIRs (2:1, 2.5:1 and 3:1). The implant wall width measurements were calculated using the software ImageJ v.1.51 through the analysis of plain x-ray examination of all the samples using standardized mounts. A fracture test was performed and scanning electron microscopy was used to evaluate maximum compression force (Fmax) and implant fractures. RESULTS: IP significantly reduced the implant wall width (P < 0.001) in all reference points of each subgroup. Fmax was significantly higher in the 2:1 subgroup (control = 1276.16 N ± 169.75; IP = 1211.70 N ± 281.64) compared with the 2.5:1 (control = 815.22 N ± 185.58, P < 0.001; IP = 621.68 N ± 186.28, P < 0.001) and the 3:1 subgroup (control = 606.55 N ± 111.48, P < 0.001; IP = 465.95 N ± 68.57, P < 0.001). Only the 2.5:1 subgroup showed a significant reduction (P = 0.037) of the Fmax between the controls and the IP implants. Most fractures were located in the platform area. Only 5 implants with IP of the 2:1 CIR subgroup had a different fracture location (4 fractures in the implant body and 1 in the prosthetic screw). CONCLUSIONS: IP significantly reduces the fracture resistance of implants with a 2.5:1 CIR. The results also suggest that the CIR seems to be a more relevant variable when considering the resistance to fracture of implants, since significant reductions were observed when unfavorable CIR subgroups (2.5:1 and 3:1 CIR) were compared with the 2:1 CIR samples.