Fas-L Expression in Articular Discs of Human TMJ

Thursday, October 10, 2013
Flavio de Alcântara Camejo DDS, MSc., School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), PhD student of the School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), Curitiba, Brazil
Luis Eduardo Almeida DDS, PhD, Oral & Maxillofacial Surgery, Hospital Universitario Evangelico de Curitiba, Curitiba, Brazil
Andrea Doetzer DDS, PhD, Oral & Maxillofacial Surgery, Hospital Universitario Evangelico de Curitiba, curitiba, Brazil
Karina Sao Thiago Caporal , Undergraduate student of the School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), Curitiba, Brazil
Viviane Ambros , Undergraduate student of the School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), Curitiba, Brazil
Paula Cristina Trevilatto DDS, MDS, PhD, School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), Professor of the School of Health and Biosciences at Pontifícia Universidade Católica do Paraná (PUCPR), Curitiba, Brazil
Background: In diseases of the TMJ, the synovium and articular cartilage produce various mediators, such as IL-1 and Fas-L (CD95L) that have the potential to induce chondrocyte death through necrosis or apoptosis. Previous studies have shown that mechanism of apoptosis plays an important role in the progression of ID of the TMJ. This study aims to examine, by immunohistochemistry, the expression of FasL, an apoptosis-inducing factor, in temporomandibular joint (TMJ) articular discs of patients with anterior disc deslocament with (ADDwR) and without reduction (ADDwoR) Methods: A sample of Forty-two (n=42) TMJ articular discs from 29 patients (mean age 32.7 years, range from 18 to 56 years) were recruited for study from the patient pool at the Evangelico School Hospital (Curitiba- PR, Brazil), between 2010-2012, and were divided into: 8 control, 17 ADDwR, 17 ADDwoR. The area of immunostaining was compared statistically between groups (p<0.05). Results: Statistically significant differences were found in the expression of FasL in TMJ discs between the three groups (p=0.001). ADDwR presented significant higher FasL expression when compared to ADDwoR (p<0.001). Conclusion: A higher area of in situ immunostaining of FasL was found in temporomandibular discs with reduction, which is the less severe condition. 

References: 1) Imirzalioğlu P, Uçkan S, Güler N, Haberal A, Uçkan D. Synovial apoptosis in temporomandibular joint disc displacement without reduction. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Nov;108(5):693-8. Epub 2009 Aug 28. 2) Loreto C, Almeida LE, Trevilatto P, Leonardi R. Apoptosis in displaced temporomandibular joint disc with and without reduction: an immunohistochemical study. J Oral Pathol Med. 2011 Jan;40(1):103-10. doi: 10.1111/j.1600-0714.2010.00920.x.