Evaluation of relationship between curve of spee and temporomandibular joint symptoms in patients referred to Occlusion section of Prosthodontics department of Mashhad Dental School

Background & Aim: Thetemporomandibular joint works in conjunction with other neuromuscular components. Defects in any of these components or factors prevent their coordinated activity and lead to temporomandibular disorders (TMD). The aim of this study was evaluation of relationship between depth of curve of spee and symptoms of temporomandibular disorders in patients referred to Occlusion section of Prosthodontics department of Mashhad Dental School during 2018-2019. Material and methods: 55 patients were studied in Mashhad Dental School. TMD symptoms included pain severity, maximum mouth opening (MMO), and the joint click was examined. Pain severity was assessed using the Visual Analogue Scale. Then, the alginate impression was prepared from the mandible and casts made and trimmed with type IV stone. Finally, a digital ruler used to measure the depth of the curve of Spee in the mandible and the relationship between the symptoms and the depth of curve of Spee measured by independent t-test. Results: Thirty-eight women (69.1%) and 17 men (30.9%) with a mean age of 28.1 ± 7.2 years and age range of 15 to 52 years were studied. The mean total depth of curve of Spee in females was 2.08 ±0.78 mm and in males was 1.72 ± 0.67 mm, which was not statistically significant (p = 0.86). Also, the mean total depth of curve of Spee in patients with and without TMJ click was 1.82 ± 0.52 mm and 2.09 ± 0.90 mm, respectively which was not statistically significant (p = 0.18).Also, there is no siginificant difference between  MMO and severity of pain with curve of space. (P>0.05) Conclusions: In this study, although the mean depth of Curve of Spee in the patients with joint click was lower than the patients without joint click, this difference was not statistically significant. There was also no significant relationship between other symptoms of patients with TMD including pain intensity, maximal mouth opening (MMO) and Curve of Spee in the mandible.