Abstract:

Objective　To study the characteristics of dental arches in the patients with facial asymmetry.Methods　20 facial asymmetrical patientswere chosen as the study subjects. Theywere 8 boys and 12 girls, aged from12-yearto 16-year old. 20 nor- mal occlusion persons without signs of facial asymmetry were chosen as control. Dental casts were measured by 3-dimension mea- suring machine. Dental arch asymmetry, coordination between upper and lower dental arch, and dental inclinationwere measured. SAS 6·03 was used in statistical analysis.Results　The distance from cuspid and the first bicuspid to the median palatal raphe in the side of crossbite was largerthan that of contralateral side in maxilla. The distance from cuspid, bicuspids and the firstmolarto the midline in the side of crossbite was smaller than that of contralateral side in mandible(P<0·05). The dental arch width of cuspid and first premolar in maxilla was smaller than that of mandible(P<0·05). Significant buccal inclination of the maxillary posterior teeth coupledwith lingual inclination of the mandibular posteriorteethwas found on the crossbite side. In contrast, signif- icant lingual inclination of the maxillary posterior teeth coupled with buccal inclination of the mandibular posterior teeth was found on the contralateral side(P<0·05).Conclusion　Thewidth of upper anterior dental archwas smaller, and the inclination of up- per and lower posterior teeth between crossbite side and counterside was different in facial asymmetry patients.

Key words: facial asymmetry, dental arch, symmetry, dental inclination, dental cast measurement