Mandibular growth, remodeling, and maturation during infancy and early childhood.

OBJECTIVE

To describe the growth, maturation, and remodeling changes of the mandible during infancy and early childhood.

MATERIALS AND METHODS

Seven Bolton-Brush Growth Study longitudinal cephalograms (N = 336) of each of 24 females and 24 males, taken between birth and 5 years of age, as well as early adulthood, were traced and digitized. Five measurements and nine landmarks were used to characterize mandibular growth, remodeling, and degree of adult maturity.

RESULTS

Overall, mandibular length showed the greatest growth changes, followed by ramus height and corpus length. Corpus length was the most mature of the three linear measures; ramus height was less mature than overall mandibular length. The greatest growth rates occurred between 0.4-1 year; yearly velocities decelerated thereafter. The ramus remodeled superiorly only slightly more than it remodeled posteriorly. Male mandibles were significantly (P < or = .05) larger, displayed greater growth rates, and were significantly less mature than female mandibles. There were no significant differences in mandibular growth or maturation between Class I and Class II patients.

CONCLUSIONS

The mandible displays decelerating rates of growth and a maturity gradient during infancy and early childhood, with males showing more growth and being more mature than females.