Comparative histological evaluation of intra- and extraorally de-epithelialized connective tissue graft samples harvested from the posterior palate region

Background: Autologous connective tissue graft (CTG) is generally considered the gold standard for peri-implant soft tissue phenotype modification and root coverage therapy. The presence of epithelial remnants in CTG has been associated with complications after soft tissue augmentation surgery. However, a specific method for de-epithelization that is patently superior has not been identified yet. This study aimed to evaluate the effectiveness of two different approaches to de-epithelialize CTG samples harvested from the posterior palate. Methods: Patients in need of periodontal or implant-related surgery that required harvesting a CTG from the posterior palate region were recruited. CTG samples harvested with an indirect approach were de-epithelialized using either an intraoral (IO group) or an extraoral (EO group) method. Tissue specimens were subsequently processed for histological analysis. The presence or absence of oral epithelial remnants was determined by two examiners using light microscopy. Results: Twenty-four patients, who provided a total of 46 analyzable CTG samples, were enrolled in this study. Histological assessment revealed that 19 out of 22 samples in the IO group were free of epithelial remnants. In the EO group, 20 out of 24 samples did not exhibit epithelial residues. These results translate into 86.4% and 83.3% of epithelium-free samples in the IO and EO groups, respectively. Conclusions: Although the intraoral method may provide several practical advantages compared with the extraoral technique, both approaches for de-epithelialization of CTG samples harvested from the posterior palate region tested in this study were comparably effective. However, none of these methods ensured complete removal of the oral epithelium in a predictable manner, which should be considered in clinical practice.