[Age-related changes in the pulp chamber and its wall in human canine teeth]

A total of 21 extracted, vital human canines (i.e., 8 maxillary and 13 mandibular) of patients between 40 and 78 years of age has been used to study, by means of X-rays and scanning electron microscopy, the age-related restriction of the pulp chamber and of the root canal, and the structure of its inorganic dentinal walls. This was done at the mesial and distal as well as the vestibular and oral aspects of the pulp chamber walls. In addition, the density of the openings of the dentinal tubules was, under standardized conditions, determined at the coronal part of the pulp chamber, in the middle of the root canal and apically on each of the four aspects of the pulp chamber, i.e. vestibularly, mesially, orally and distally. The results demonstrated that (1) pulp chamber and root canal of both maxillary and mandibular canines, with increasing age of the patients, does not become very much restricted in the vestibulo-oral direction and only very little or patchwise in the mesio-distal direction, (2) fibrodentin that causes such restriction, is deposited in greater amounts only after 60 to 70 years of age, and (3) the density of the tubules is very variable, rather similar in the coronal crown chamber and the middle of the root canal, both mesio-distally and vestibulo-orally, and decreases sharply towards the root apex. These findings are discussed mainly with respect to the age-related changes in the pulp chamber and root canals of human central and lateral incisors.