SEX-RELATED CHANGES IN THE BONE-MINERAL CONTENT OF ATROPHIC MANDIBLES

In 25 edentulous anatomical mandible specimens (15 female, age range 6 9-90 years; 10 male, age range 68-88 years), the bone mineral content (BMC) was measured by dual-photon absorptiometry (DPA) and analyzed in a standardized area of the mandibular body. The results of our BMC ex aminations showed that there was a significant difference (P = 0.05) b etween the two sexes. Another notable fact was that, with advancing ag e, the values measured in the male mandibles tended to increase slight ly but in a statistically significant way. Those of the female mandibl es tended to decrease with age. A possible explanation for this observ ation may be derived from the fact that a reduction of the mandibular height leads to a reduction of the moment of resistance. As functional adaptation in order to preserve the stability of the atrophic body of the mandible, the amount of inner cortical bone of the male mandibles increases, leading to a reduction of the cancellous portion. In the m andibles of women, postmenopausal osteoporosis seems to prevent an ana logous compensation mechanism.