Labial soft tissue volume evaluation of different techniques for ridge preservation after tooth extraction: a randomized controlled clinical trial.

OBJECTIVE: To volumetrically evaluate soft tissue changes of different ridge preservation techniques compared to spontaneous healing 6 months after tooth extraction. MATERIALS AND METHODS: In each of 40 patients, one single-rooted tooth was extracted and four treatment modalities were randomly assigned to the following groups (n = 10 each): A) ss-tricalcium-phosphate-particles with a polylactid coating (ss-TCP), B) demineralized bovine bone mineral with 10% collagen covered with a collagen matrix (DBBM-C/CM), C) DBBM with 10% collagen covered with an autogenous soft tissue punch graft (DBBM-C/PG), D) spontaneous healing (control). Impressions were obtained before extraction and 6 months later, casts were digitized and volumetric changes at the buccal soft tissues were determined. One-way anova was performed and pair-wise Wilcoxon rank sum test with Bonferroni-Holm method was applied for comparison of differences between two groups. RESULTS: After 6 months, horizontal contour changes accounted for -1.7 +/- 0.7 mm (A), -1.2 +/- 0.5 mm (B), -1.2 +/- 0.7 mm (C) and -1.8 +/- 0.8 mm (D). None of the group comparisons reached statistical significance. CONCLUSIONS: Six months after tooth extraction all groups revealed a horizontal volume change in the buccal soft tissue contour. Application of DBBM-C/CM or DBBM-C/PG reduced the amount of volume resorption compared to ss-TCP or spontaneous healing without reaching statistically significant difference.