A mandibular fossa depth correlation with dental condition and age in humans. 120 fresh male mandibular fossas were measured from the deepest area of the fossa to a horizontal reference line. The samples were classified according to age and dental state (dentate, partially dentate and totally edentulous) and a multivariate analysis was employed. Subjects average age was 41.1 (20-85). There were more partially dentate individuals (59.16%) than dentate (30%) or edentulous ones (10.83%). Average fossa depth was 6.9 mm (6.6-7.1 mm 95%CI) which significantly decreased with increased age and dental health deterioration (p<0.01). A period of five years edentulism increased the likelihood of mandibular fossa flattening (<6.9 mm) by 20.6% and 7.2% in dentate ones. Our findings found an association between dental state and age as determinant factors in reducing mandibular fossa depth.