Alveolar bone loss in a strain of mice.

Abstract

Alveolar bone loss with increasing age was compared in strain STR/N and random‐bred Swiss‐Webster mice. All animals were fed pelleted laboratory chow and tap water and killed at 3 month intervals from 3–18 months of age. Alveolar bone loss was quantitated by measuring loss of alveolar crest height on the lingual aspect of the defleshed right hemimandible, and by planimetric measurement of the quantity of trabecular bone in a single undecalcified mesiodistal section of the same hemimandible. The left hemimandible was fixed in formalin and examined histologically. There was a progressive severe loss of alveolar bone with increasing age in strain STR/N mice, which was not observed in random‐bred Swiss‐Webster mice. Histologically, the bone loss was associated with progressive gingivitis and periodontal pocket formation. The bone loss was not related to hair or bedding impaction or to obvious dental morphological differences between the two strains. Systemic disturbances such as generalized osteoporosis or diabetes mellitus were not present. The occurrence of bone loss in STR/N mice in the absence of any applied stimulus suggests that this strain is suitable for studying mechanisms of alveolar bone loss and factors capable of modifying bone loss.