Dimensions of central incisors, canines, and first molars in subjects with Down syndrome measured on cone-beam computed tomographs

• The maxillary teeth of patients with Down syndrome are smaller than those of the controls.
• No clear sexual dimorphism was detected.
• Crown dimensions showed a progressive reduction with age.
• There appeared to be a degree of “fluctuating dental asymmetry.”

IntroductionThe literature on tooth dimensions in subjects with Down syndrome (DS) is scarce. To our knowledge, no studies have yet been published in which the morphometry of the teeth in DS subjects has been determined using computed tomography.MethodsThe study group consisted of 40 subjects with DS, aged 10 to 40 years. An age- and sex-matched control group was selected. Cone-beam computed tomography images were retrieved from the archive of the Santiago de Compostela University in Spain. The maxillary central incisors, canines, and first molars were evaluated. The following variables were analyzed: overall tooth length, crown height, root length, mesiodistal diameter, vestibular-palatine diameter, crown-to-root ratio, and cervical circumference.ResultsThe teeth of subjects with DS were smaller than those of the controls, although the crown-to-root ratio was maintained. No clear sexual dimorphism was detected, but the root lengths of the incisors were greater in male subjects. Crown height, mesiodistal diameter, and crown-to-root ratio showed progressive reductions with age. There appeared to be a degree of “fluctuating dental asymmetry” with respect to vestibular-palatine diameter and cervical circumference.ConclusionsOur findings confirm microdontia of the permanent teeth and progressive reductions in tooth sizes with age in persons with DS. These variations might be relevant to orthodontic treatment planning.