OBJECTIVE: This study aimed to evaluate levels of expression of nestin, CD34 and transforming growth factor β3 (TGFβ3) in facial tissue of children with complete unilateral (CU) and complete bilateral (CB) cleft lip and palate (CLP). MATERIALS AND METHODS: Twenty-nine CLP patients were enrolled in this study (18 boys and 11 girls). Tissue samples were collected during primary and repeated plastic surgery correction for CU (n=10) or CB (n=19) cleft palate (age range 3 months - 9 years, 6 months). Immunohistochemistry was used to assess levels of nestin, CD34 and TGFβ3. Positively stained cells were graded semi-quantitatively. Data were analyzed to compare cell counts between CUCLP and CBCLP, and CLP at an age before and during primary dentition and CLP in mixed dentition age patients using the Mann Whitney U-test (P<0.05). RESULTS: Moderate to abundant numbers of nestin immunoreactive structures were observed in the oral mucosa. CD34 antibodies labeled all microvessels in lamina propria of the CLP affected tissue, while low numbers of TGFβ3 positive cells were scattered in the connective tissue. There were no statistically significant differences between the study groups. CONCLUSION: Expression of nestin in complete unilateral and bilateral cleft lip and palate affected soft tissue indicates a potential increase of tissue regeneration. CD34 positive oral mucosa cells suggest increased angiogenesis, while the sporadic expression of TGFβ3 indicates an insignificant role in the maintenance and growth of cleft affected oral mucosa stem or progenitor cells. Nevertheless, scarce expression of TGFβ3 suggests a role in cleft morphopathogenesis.publishersversionPeer reviewe