Postnatal changes in osseous and mucosal morphology of the hard palate.

We investigated the postnatal changes in the dimensions, configuration, and surface pattern of the hard palate in 68 skulls, ranging in age from birth to 90 years of age. The number of palatine rugae of the palatine mucosa was assessed in 168 living subjects aged 11-98 years. Before the first dentition appeared, the osseous palate was concave, smooth, and lacked alveolar processes. In maxillar specimens from the end of the first year to the end of the fourth year of life, balloon-like osseous formations, containing the elements of permanent teeth, appeared bilaterally behind the deciduous incisors. With age, the concavity of the palate diminished and became flat with the loss of the teeth. The presence of teeth was associated with the height of the alveolar ridge, which decreased from 7.3 +/- 4.4 mm in specimens with intact teeth to 4.7 +/- 4.1 mm in specimens without teeth (P = 0.020). Palatine rugae were a common finding in living subjects, but were more often absent in older age (2.2% in 11-50 age group vs. 12.8% in 51-98 age group, P = 0.0183). Our results suggest that the morphology of the hard palate rapidly changes during deciduous and permanent teeth eruption and is related to the presence of alveolar ridges and teeth in adults. Palate osseous morphology may be morphologically and functionally independent from its mucosal morphology. Changes in the morphology of the osseous palate are clinically relevant for dental prosthetics and tooth implantation.