Porcelain-Fused-to-Metal and All-Ceramic Implant-Supported Rehabilitation of Maxillary Lateral Incisors Agenesis

Method: Seventy-two patients affected by monolateral or bilateral agenesis of the maxillary lateral incisors were selected. One hundred and five narrow diameter implants were inserted and loaded 3 months after the surgical procedures. The final restorations were realized using either titanium abutments with aureo-galvan crowns veneered with feldspathic ceramics (group 1) or zirconia abutments with all-ceramic (alumina or zirconia) crowns stratified with dedicated veneering ceramics (group 2). The follow-up period ranged from 24 to 77 months. Both marginal bone resorption and soft tissue quality were evaluated. The data were statistically analysed using analysis of variance (ANOVA) for repeated measures, one-way ANOVA and Tukey’s post hoc test (p=0.05). 

Result: No statistically significant differences in functional and esthetic outcomes were found between group 1 and 2. During the 24- to 77-month follow-up period, no implant showed either pain and sensitivity or mobility. In group 1 survival and success rates of 97.1% (1 loss at follow-up) and 94.1% (1 estethic failure) were recorded respectively. Conversely, in group 2 survival and success rates of 98.6% (1 loss at follow-up) and 94.4% (1 chipping, 1 ceramic fracture, 2 unscrewings) were recorded respectively. After 77 months of functional loading, a cumulative survival rate of 98.1% and a cumulative success rate of 95.2% were calculated.

Conclusion: In case of maxillary lateral incisor agenesis, the implant–prosthetic approach has proved to be a reliable and predictable treatment to restore function and aesthetics. Satisfactory values of marginal bone resorption over time and optimal conditions of peri-implant tissue around narrow diameter implants were found around both titanium and zirconia abutments. Optimal aesthetic results were achieved using both aureo-galvan and all-ceramic crowns.