Incidence of inter-proximal papilla between a tooth and an adjacent immediate implant placed into a fresh extraction socket: 1-year prospective study

Background: Implant single-tooth replacement with a natural appearance is a challenging and demanding procedure. The aim of this prospective study was to identify the factors affecting the presence of an inter-proximal papilla between a tooth and an implant. Methods: Forty-six patients with a total of 46 teeth scheduled for tooth extraction and immediate implant placement into fresh sockets were included in the study. Immediate implants were positioned after teeth removal. After 4 months of healing, the implants were restored with single crown fixed prostheses. The following parameters were assessed: (1) presence/absence of the inter-proximal papilla, (2) gingival index, (3) inter-implant tooth distance (ITD) and (4) distance from the base of the contact point to the inter-dental bone (CPB). A computerized analysis was performed to determine ITD and CPB values after converting perioapical radiographs to digitalized images. Statistical analyses were performed to determine the effect of ITD and CPB on the presence or absence of the inter-proximal papilla. Results: All the implants were restored, so that a 100% of implant survival rate was observed after 12 months of function. Mean values were recorded for ITD and CPB parameters, respectively. When ITD was 3-4mm, and CPB was 3-5mm, the inter-proximal papilla was significantly present (P<0.05). Conclusions: The recommended inter-proximal space dimensions are 3-4mm between an implant and the adjacent tooth, and 3-5mm between the base of the CPB. The interaction between the surgical and prosthetic plans represents the key factor to optimize the edentulous site for predictable anterior single-implant esthetics.