Ying-Bin Yan1, Jiang-Ming Li2, E Xiao2, Jin-Gang An2, Ye-Hua Gan3, Yi Zhang4. 1. Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, PR China; Department of Oral and Maxillofacial Surgery, Tianjin Stomatological Hospital, 75 Dagu Road, Heping District, Tianjin 300041, PR China. 2. Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, PR China. 3. Laboratory of Molecular Biology and Center for Temporomandibular Disorders and Orofacial Pain, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, PR China. Electronic address: kqyehuagan@bjmu.edu.cn. 4. Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, PR China. Electronic address: zhangyi2000@263.net.
Abstract
OBJECTIVE: The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and condylar fracture healing. METHODS: The cDNA from either the bony ankylosed callus or fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and condylar fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. RESULTS: Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to condylar fracture at several time points (P < 0.05). CONCLUSION: Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.
OBJECTIVE: The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and condylar fracture healing. METHODS: The cDNA from either the bony ankylosed callus or fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and condylar fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. RESULTS:Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to condylar fracture at several time points (P < 0.05). CONCLUSION: Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.