Effect of polydeoxyribonucleotide with xenogeneic collagen matrix on gingival phenotype modification: a pilot preclinical study

Purpose: To investigate the effect of xenogeneic collagen matrix (XCM) with polydeoxyribonucleotide (PDRN) for gingival phenotype modification compared to autogenous connective tissue graft. Methods: Five mongrel dogs were used in this study. Box-type gingival defects were surgically created bilaterally on the maxillary canines 8 weeks before gingival augmentation. A coronally positioned flap was performed with either a subepithelial connective tissue graft (SCTG) or XCM with PDRN (2.0 mg/mL). The animals were sacrificed after 12 weeks. Intraoral scanning was performed for soft tissue analysis, and histologic and histomorphometric analyses were performed. Results: One animal exhibited wound dehiscence, leaving 4 for analysis. Superimposition of STL files revealed no significant difference in the amount of gingival thickness increase (ranging from 0.69 +/- 0.25 mm to 0.80 +/- 0.31 mm in group SCTG and from 0.48 +/- 0.25 mm to 0.85 +/- 0.44 mm in group PDRN; P> 0.05). Histomorphometric analysis showed no significant differences between the groups in supracrestal gingival tissue height, keratinized tissue height, tissue thickness, and rete peg density ( P> 0.05). Conclusions: XCM soaked with PDRN yielded comparable gingival augmentation to SCTG.