Papillary fill response in single-tooth implants using abutments of different geometry.

Objective To evaluate the influence of abutment geometry on papillary fill in the esthetic zone in a delayed crown protocol. Materials and methods Twenty-six subjects received two non-adjacent endosseous implants in the esthetic zone. Functional temporary crowns were installed 17-19 weeks later, using conventional (control) and curved (experimental) abutments. The abutments were randomized in each patient independently. Final crowns were cemented after 2 months ( T0). Standard intraoral photographs and radiographs were made to evaluate papillary fill after 12 months ( T12). The interproximal papilla fill was measured by means of the papilla index score ( PIS) and related to the maximum bone level between the implant and the adjacent root as well as the peri-implant marginal bone level at T12, both measured radiographically. Results No statistically significant difference between the experimental and the control group could be demonstrated ( P = 0.25). Ordinal regression analysis showed a positive correlation between the maximum bone level and papilla fill ( P < 0.01) and a negative correlation between the peri-implant marginal bone level and papilla fill ( P < 0.05). Conclusion A concave abutment does not exhibit a better fill of the papilla compared with a straight abutment in single-tooth implant placement using a delayed protocol in the esthetic zone after 12 months of function. [ABSTRACT FROM AUTHOR]