Analysis of risk factors related to early implant failure: A retrospective study.

STATEMENT OF PROBLEM: Factors influencing early implant failure (failure during the healing period) in the rehabilitation and restoration of oral function in partially edentulous patients are unclear. PURPOSE: The purpose of this clinical study was to investigate several factors that may be associated with early implant failure. MATERIAL AND METHODS: This retrospective study was conducted on 3247 implants in 2061 patients between 2009 and 2022. Patient-related and surgery-related factors, including smoking; sex; diabetes; bone grafting; implant length, diameter, and design; adjacent teeth; and insertion torque, were manually retrieved and analyzed. Using univariate and multivariate analyses, a generalized estimating equation (GEE) model with chi-squared tests was employed to evaluate factors related to early implant failure (the failure before restoration) (α=.05). RESULTS: The mean ±standard deviation age of the study patients was 49.2 ±15.0 years (range 18 to 91). Ninety-nine implants (3.05%) failed during the healing period. Three factors were statistically significant regarding early implant failure: smoking (odds ratio [OR]=1.92, P=.008), implant design (tapered implants) (OR=1.84, P=.007), and implant length <10 mm (OR=2.98, P=.011). Factors including diabetes, bone grafting, anatomic location, adjacent teeth (endodontic therapy in the adjacent teeth and the distance between implant and adjacent teeth), healing method, and insertion torque did not exhibit a statistically significant higher early implant failure rate. Ninety-three sites with failed implants received new implants, and 6 of these 93 implants failed during the healing period. CONCLUSIONS: Within the limitation of sample size, smokers, implant length (<10 mm), and implant design (tapered implant) exhibited higher risk of early implant failure in this retrospective study. Implant insertion torque, healing method, adjacent teeth, and diabetes did not significantly influence the risk of early implant failure.

Factors impacting new bone formation in transcrestal sinus floor elevation followed by implant placement: a cross-sectional study.

OBJECTIVES: This study aimed to evaluate factors related to new bone formation (NBF) following simultaneous implant placement with transcrestal sinus floor elevation (TSFE). MATERIALS AND METHODS: Between 2008 and 2020, 357 implants (276 patients) were placed with TSFE. Clinical and radiographic examinations were performed at the preoperative, postoperative, restoration, and follow-up stages. Marginal bone loss, during healing, and the survival rate were retrospectively analyzed. RESULTS: Implant protrusion lengths (IPL: 3-5 mm) significantly influenced NBF during the healing period (P-value = 0.026, Odds Ratio = 1.15, 95% confidence interval = 1.02- 1.30). Bone grafting was correlated with NBF (P-value = 0.001). The distance between the implant and lateral wall of the sinus (mesial: P-value = 0.041, distal: P-value = 0.019, buccal: P-value = 0.032, lingual: P-value = 0.043) and angle between the implant and sinus floor significantly influenced NBF in four directions (mesial: P-value = 0.041, distal: P-value = 0.02, buccal: P-value = 0.047, lingual: P-value = 0.005). Implant shape (cylindrical or conical), perforations, smoking, and diabetes did not significantly affect NBF during the healing period (P > 0.05). CONCLUSION: Increasing the distance and angle between the implant and lateral wall of the sinus floor corresponded with reduced NBF. IPL may be an important factor that should be considered. CLINICAL RELEVANCE: Our study analyzed new bone formation following transcrestal sinus floor elevation among patients who underwent this procedure with simultaneous implant placement, several factors (including angle and distance between sinus and lateral wall and implant protrusion length) were included in our study.

The survival rate of transcrestal sinus floor elevation combined with short implants: a systematic review and meta-analysis of observational studies.

BACKGROUND: Currently, insufficient bone volume always occurs in the posterior maxilla which makes implantation difficult. Short implants combined with transcrestal sinus floor elevation (TSFE) may be an option to address insufficient bone volume. PURPOSE: The clinical performance of short implants combined with TSFE was compared with that of conventional implants combined with TSFE according to the survival rate. METHOD: In this systematic review and meta-analysis, we followed the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Articles were identified through PubMed, Embase, the Cochrane Library, and manual searching. Eligibility criteria included clinical human studies. The quality assessment was performed according to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. The odds ratio (OR) with its confidence interval (CI) was considered the essential outcome for estimating the effect of short implants combined with TSFE. RESULTS: The registration number is INPLASY202050092. Eleven studies met the inclusion criteria, including 1 cohort study and 10 cross-sectional studies. With respect to the 1-year survival rate, no significant effect was observed between short implants (length ≤ 8 mm) and conventional implants combined with TSFE (I2=0%, OR=1.04, 95% CI: 0.55-1.96). Similarly, no difference was seen between the two groups regarding the survival rate during the healing period (I2=10%, OR=0.74, 95% CI: 0.28-1.97) and 3-year loading (OR=1.76, 95% CI: 0.65-4.74). CONCLUSION: There was no evidence that the survival rate of short implants combined with TSFE was lower or higher than that of conventional implants combined with TSFE when the residual bone height was poor and the implant protrusion length of short implants was less than or similar to conventional implants. Nevertheless, the results should be interpreted cautiously due to the lack of random controlled trials in our meta-analysis.

Two-stage transcrestal sinus floor elevation-insight into replantation: Six case reports.

BACKGROUND: Transcrestal sinus floor elevation (TSFE) has been widely used in the oral clinic when the residual bone height (RBH) exceeds 5 mm. However, when there is insufficient RBH in the posterior maxilla, two-stage TSFE may be an option. CASE SUMMARY: This article introduces the concept of two-stage TSFE. Six patients had osseointegration failure after TSFE. For the first-stage surgery, we restricted the vertical bone augmentation as much as possible. At the second-stage surgery, the increased RBH was 3.28 ± 1.55 mm, which was beneficial for surgery. Five implants functioned successfully on schedule, but one implant failed again during the healing period. A third surgery was performed, and the implant functioned successfully. CONCLUSION: When RBH was less than 5 mm, two or more procedures of TSFE might result in a higher RBH.