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Facial bone alterations on maxillary anterior single implants for immediate placement and provisionalization following tooth extraction: a superimposed cone beam computed tomography study.

OBJECTIVES
The purpose of this cone beam computed tomography (CBCT) study was to describe the facial bone changes around single implants for immediate placement and provisionalization following tooth extraction in the maxillary anterior.


MATERIAL AND METHODS
The data between 2008 and 2013 were collected retrospectively. Superimposed facio-palatal cross-sectional CBCT images for the implants were derived from preoperative and postoperative radiographs via standardized CBCT processes. Horizontal and vertical facial measurements on the implants were identified at preoperative and approximately 1-year postoperative follow-ups. Correlation coefficient for those parameters was evaluated.


RESULTS
A total of 12 single implants in 12 patients were included in this study. The mean loading period was 13.3 months (range 12-15 months). The median data of preoperative bone thickness 0.54 mm (A), preoperative vertical bone level 1.46 mm (B), postoperative bone thickness 1.77 mm (C), postoperative vertical bone level 1.08 mm (D), horizontal distance from outer surface of preoperative facial bone to implant surface 2.08 mm (E), horizontal gap distance 1.41 mm (E-A), horizontal bone resorption -0.26 mm (E-C), and vertical bone resorption -0.25 mm (B-D) were obtained. The data at the implant platform level (IPL) were selected for the horizontal measurements. Spearman's analysis demonstrated statistically significant correlations between B and D, C and E, E and E-A, and B and E-C (P < 0.01). Significant correlations between C and B, D, and E-A were also found, respectively (P < 0.05).


CONCLUSIONS
Immediate placement and provisionalization of single implants procedure in the maxillary anterior showed excellent outcomes with the small facial bone alterations around the implants. Neither preoperative facial bone thickness nor horizontal gap distance influenced the amount of facial bone resorptions.