Gingival biotype modification with collagen matrix or autogenous subepithelial connective tissue graft - Histologic and volumetric analysis in dogs -

Abstract

1. Background: Gingival biotype modification (GBM) is a surgical procedure to increase the gingival thickness at sites where gingival recession could be expected such as anterior teeth. Although it is common to use subepithelial connective tissue grafts (SCTGs) from the palate of patients, several biomaterials are used with the development of material science and convenience of surgery. In this study, we evaluated the volumetric effect and biocompatibility of porcine type I collagen matrix graft (CG) on the GBM compared to SCTG in the beagle model.

2. Methods: Six adult dogs were used in this experiment. Each dog received an autologous SCTG from their palatal donor site or CG at the labial attached gingiva by sub-periosteal tunneling technique. Scanning dental stone model and three-dimensional digital volume analysis were conducted to compare the effects of CG and SCTG on gingival thickness increase before and after surgery. Histological and histomorphometric analysis were performed to evaluate the healing pattern and biocompatibility of CG on the GBM at five months after the surgery.

3. Results: In the volume analysis, the increase of soft tissue thickness was 0.45 ± 1.07 mm and 0.69 ± 0.81 mm after one month, 0.06 ± 0.36 mm and 0.11 ± 0.32 mm after five months in the SCTG and CG groups, respectively with no significant difference between the groups. In the histological and histomorphometric analysis, the average soft tissue thickness was 1.80 ± 0.34 mm and 1.79 ± 0.40 mm in the SCTG and CG, respectively with no significant difference between the groups. Expressions of type I collagen and VEGF were found in both SCTG and CG groups at five months with no significant difference between groups in quantitative analysis.

4. Conclusions: CG and SCTG seem to have equivalent efficacy on the GBM in the volume increase and biocompatibility.