Dimensions of buccal bone and mucosa at immediately placed implants after 7 years: a clinical and cone beam computed tomography study

Abstract

The objective of this study was to evaluate the dimensions of buccal bone and soft tissue at immediately placed implants over a 7-year period. Twenty-four patients, that participated in a clinical prospective study and received implants immediately placed into extraction socket, were enrolled for this study. Residual bone defects were grafted with xenogenic bone substitute and covered by means of collagen membrane. Baseline examination included measurements of full-mouth plaque and bleeding scores, width of keratinized mucosa, and dimensions of residual bone defects at the buccal aspect. Seven years after implant placement, full-mouth plaque score, full-mouth bleeding score, width of keratinized mucosa, and probing pocket depth were assessed and cone beam computed tomography images acquired. Dimensions of buccal bone and soft tissue were evaluated on the cross-sectional cone beam computed tomography reconstructions. Differences between two time-points were tested using the two-sided t-test. Correlation analysis was used to investigate the influence of baseline bone defect dimensions on the bone dimensions measured at the 7-year follow-up. Fourteen patients attended the follow-up examination. In five implants almost no buccal bone was detected, whereas in the remaining nine implants the buccal bone was found covering the rough implant surface. No correlation was found between initial bone defects and bone dimensions at the follow-up examination. The sites without radiographically detectable buccal bone at the 7-year control presented with 1 mm more apical mucosal level in comparison to implants with intact buccal bone.