Craniofacial Morphology Affects Bite Force in Patients with Painful Temporomandibular Disorders

Craniofacial morphology affects masticatory performance in healthy dentate subjects, but little is known about its effects in patients with painful temporomandibular disorders (TMDs). Forty-eight female patients (mean age of 28±5.8 years) with painful TMDs underwent lateral cephalometric radiography. Using Ricketts' cephalometric analysis and the Vert method, subjects were assigned to three groups according to their craniofacial morphology: brachyfacial (n=22), mesofacial (n=13), and dolichofacial (n=13). Research diagnostic criteria for TMD were used to confirm the TMD diagnosis for each patient. Pain intensity was reported by each patient based on a visual analog scale (VAS). Maximum bite force (MBF) was measured with pressure sensors placed on the first molar site. Masticatory performance (MP) was assessed by chewing a silicone-based artificial material and determining the resulting particle size by the sieve method. Chewing ability (CA) was evaluated for seven food types and analyzed by a VAS questionnaire. Data were analyzed by one-way ANOVA followed by a Tukey-Kramer test (p<0.05). MBF differed in each group, with brachyfacial patients having the highest MBF values. There was no difference in MP among the groups. The groups differed only in their ability to chew one of the seven evaluated food types. In summary, craniofacial morphology affects the MBF without impairing MP or CA in patients with painful TMDs.