Prevalence of symptoms of functional disturbances of the masticatory system in Swedish men.

Subjective and clinical symptoms of mandibular dysfunction and cuspal interferences were studied in 389 Swedish men (median age 32 years). Impaired chewing function was noted in about 10%, different types of parafunction in 26%, frequent headaches in 5%, TMJ or muscle pain in 3% and difficulties in mouth opening in 10% of the men. Locking or luxation of the mandible was the most prevalent clinical symptom (24%), followed by reduced movement capacity and deviation on opening of the mandible, TMJ-sounds and muscle tenderness. Sixty per cent of the men had one or more clinical symptoms of dysfunction. Subjective symptoms of dysfunction were positively correlated with reduced movement capacity of the mandible and tenderness of the masticatory muscles and temporomandibular joints upon palpation. Positive correlations were found between subjective symptoms of dysfunction and non-working side interference as well as single tooth contact on the working side. Locking or luxation of the mandible and TMJ-sounds were positively correlated with single tooth contact on the working side and TMJ-sounds and muscle tenderness with interferences in the retruded position of the mandible.