Maxillary canine-first premolar transposition, associated dental anomalies and genetic basis.
Maxillary canine-first premolar (Mx.C.P1) transposition, an uncommon dental anomaly involving positional interchange of the two teeth, was studied using a sample of 43 subjects with the abnormality. Data were recorded on sidedness, sex, race, tooth agenesis, and peg-shaped maxillary lateral incisors for each case. Mx.C.P1 transposition occurred bilaterally in nearly one-quarter of the sample and favored female expression (sex ratio, M1:F3.8) and left-side occurrence (61% of unilateral cases). Familial occurrence was noted, as was a predilection for white subjects. Tooth agenesis (excluding third molars) and/or peg-shaped maxillary lateral incisors accompanied Mx.C.P1 transposition in 49% (21) of the subjects, four to ten times the normal rate of occurrence. Data from this study and the analysis of previously published cases provided strong evidence that Mx.C.P1 transposition is a disturbance of tooth order and eruptive position resulting from genetic influences within a multifactorial inheritance model.
Harvard School of Dental Medicine, Boston, MA.
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Peck
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Attia
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000848:Anodontia / Q000235:genetics; D001641:Bicuspid / Q000002:abnormalities*; D002648:Child; D003481:Cuspid / Q000002:abnormalities*; D005006:Ethnicity; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008310:Malocclusion / Q000453:epidemiology / Q000235:genetics; D008437:Maxilla; D011862:Radiography, Panoramic; D012737:Sex Factors; D014071:Tooth Abnormalities / Q000453:epidemiology / Q000235:genetics*; D014079:Tooth Eruption, Ectopic; D014481:United States / Q000453:epidemiology