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Curved abutment design does not significantly impact crown or gingival esthetics as assessed by PES and VAS scored by dentists and patients, respectively.

Abutments with a circumferential groove do not lead to a different response of the mucosal margin compared with a regular abutment, and are no more resistant upon removal than regular abutments after 6 weeks of function.

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.

Gingival biotype and crown dimensions may be important predictors for the esthetic outcome of surgical procedures. However, the visual distinction between "thick" and "thin" biotype may not be a suitable predictive parameter of surgical outcome. Intraoral photographs of 73 Indian and Dutch subjects were matched with respect to age and gender and were used to determine the gingival biotype (subjective assessment) and crown dimensions (objective assessment). Intraobserver and interobserver agreement was determined for subjective measurements (Cohen's kappa), and the error of the method was calculated for the objective measurements (Dahlberg formula). Intraobserver agreement for the subjective assessment of gingival biotype was adequate (κ = 0.49-0.60), but interobserver agreement was poor (κ = 0.10), whereas the error of the method for objective assessment of crown dimensions was small. The mean crown width-length angle is smaller in Dutch as compared to Indian subjects in this sample (P < .05). Crown dimensions may be a more quantitative approach and could become a future norm to predict outcomes of implant restorative and surgical procedures, bearing in mind that cross-cultural differences may be present.