Retrospective and Clinical Evaluation of Aftermarket CAD/CAM Titanium Abutments Supporting Posterior Splinted Prostheses and Single Crowns.

Abstract

To evaluate the clinical outcomes of aftermarket computer-aided design/computer-assisted manufacturing (CAD/CAM) titanium abutments supporting splinted prostheses and single crowns in the posterior region. This study retrospectively evaluated the records of patients who received posterior implant-supported splinted restorations and single crowns supported by aftermarket CAD/CAM titanium abutments. Recall and clinical examination of the patients were performed between January 2017 and February 2018. A logistic regression was conducted to evaluate the influence of variables on the occurrence of complications and success rates. Correlations between the bone-level change and variables were calculated using the Spearman correlation. One hundred thirty-five patients with 287 implants (86 crowns and 97 splinted prostheses) were recalled and examined clinically and radiographically after a mean observation period of 6.3 ± 1.2 years (range 4.1 to 9 years). Failure of 3 implants led to a survival rate of 99.0%. Complications included 18 (9.8%) ceramic chippings, 15 (8.2%) screw loosenings, 8 (4.4%) decementations, 52 (38.5%) patients with peri-implant mucositis, and 9 (6.7%) patients with peri-implantitis. A significantly higher incidence of ceramic chipping occurred with bruxers (odds ratio [OR] = 3.939, 95% confidence interval [CI] = 1.28-12.09, P < .05). All screw loosenings occurred in single crowns. All decementations were observed in restorations cemented with temporary cement. Marginal bone loss around implants was significantly correlated with smoking (r = -0.155, P < .05). Hypertension was significantly associated with peri-implant mucositis (OR = 4.7, 95% CI = 1.65-13.39, P < .05). The technical success rate was 80.1%. The biologic success rate was 57%. There was no association between the restoration type and the success rates of the restorations. Using aftermarket CAD/CAM titanium abutments to support posterior restorations yielded comparable survival and success rates after a mean observation period of 6 years. However, in light of the relatively high incidence of screw loosenings, especially in patients receiving single-implant crowns, informing patients of the additional chairside aftercare with this type of treatment option is recommended.