Retrospective clinical study of minimally invasive full-mouth rehabilitations of patients with erosions and/or abrasions following the "3-step technique". Part 1: 6-year survival rates and technical outcomes of the restorations.

Purpose To evaluate the survival rates and technical outcomes of minimally invasive full-mouth rehabilitations in patients affected by dental erosion and attrition. Materials and methods For this retrospective study, 28 subjects (8 women, 20 men; mean age: 45.6 years) who suffered from generalized erosions and attrition and who were treated according to the 3-step technique were invited to participate. The patient records were reviewed, and the restorations were clinically and radiographically examined. This part of the study (part 1) evaluated restoration survival and technical outcomes using the modified United States Public Health Service criteria (mUSPHS). Survival analysis was performed using Kaplan-Meier survival statistics, and comparison between subgroups was made using log-rank test. For all other comparisons, cross-tabulations of occurrence were performed, and significance was tested using Pearson chi-square test. The level of statistical significance was set at P Results A total of 19 patients (3 women, 16 men; mean age: 45.6 years) agreed to participate. In these patients, 406 restorations (149 direct composites, 110 onlays, 147 veneers) supported by 365 teeth were examined. The mean time in service was 71.8 ± 28.6 months. Six failed restorations were identified; all were direct composites. The 6-year survival rates were 97.3% for direct composites, 98.2% for onlays, and 100% for veneers (P > .05). No differences were found among materials and locations of the restorations. Nineteen technical complications included 14 partial fractures, 3 fissures, 1 wear, and 1 decementation. The mUSPHS evaluation showed good technical outcomes. Presence or absence of a nightguard influenced restoration survival (P = .003). Conclusion Minimally invasive rehabilitations of patients with erosions/attrition with the 3-step technique are a reliable treatment option in the medium term. Protective nightguards are recommended.