Dental attrition of Mayan Tzutujil children--a study based on longitudinal materials.

The purpose of this study was to evaluate dental attrition by measuring attrition volume on all types of teeth during facial growth, tooth shedding and eruption. Dental casts and cephalograms of 7 male and 7 female Mayan Tzutujil Indian children were used. Relationships were found between increase in vertical and horizontal facial growth and increase in attrition on the deciduous canines, first and second molars, permanent incisors and first molars in both arches and in both sexes. Significant increases in attrition were found on the deciduous second molars during eruption of the permanent first molars, and on the permanent incisors and first molars during eruption of the second molars in both arches and in both sexes. The results suggest that the function of attrition is 1) to compensate for increase in vertical and horizontal dimensions during facial growth, and 2) to adjust the occlusal surfaces during tooth eruption and occlusal development. In addition, an attritional index was developed to evaluate attrition among teeth. This index could be used in the future to make comparisons among different populations. Comparisons were made among Class I, II and III molar relations by using the attritional index, showing how it can be used to gain a better understanding of the characteristic patterns of dental attrition.