Dentist, Centre for Special Care Dentistry, CBT Rijnmond, Rotterdam, The Netherlands.
Am J Orthod Dentofacial Orthop. 2010 May;137(5):584.e1-9; discussion 584-5. doi: 10.1016/j.ajodo.2009.10.032.
The purposes of this study were to investigate the patterns of tooth agenesis (oligodontia and nonoligodontia), maxillary canine impaction, and tooth transposition in subjects with Down syndrome and to determine whether congenital heart disease and hypothyroidism are parameters in tooth agenesis.
The study included 114 patients with Down syndrome. The data were quantified by using standardized records, clinical examinations, panoramic radiographs, and solo roentgenograms. The subjects were differentiated into oligodontia (6 or more teeth missing) and nonoligodontia (5 or fewer teeth missing).
In these patients with Down syndrome, 59.6% had missing teeth. Those in the nonoligodontia group showed a tendency toward a negative correlation between congenital heart disease and agenesis (P = 0.093; odds ratio = 0.49) but a slight positive correlation between hypothyroidism and agenesis (P = 0.060; odds ratio = 3.71). In the oligodontia group, there was a quantitatively and qualitatively different pattern, indicating another phenotype. When both mandibular central incisors were missing, there was a remarkable chance for oligodontia (P = 0.001; odds ratio = 38.8). In the mandible, symmetrical agenesis of the canines and lateral incisors was more frequent in the nonoligodontia group.
The oligodontia (with a different phenotype) and nonoligodontia groups had different patterns of agenesis. Maxillary canine impaction was not related to absence of the lateral incisors. Absence of both mandibular central incisors was a high predictor for oligodontia. Congenital heart disease and hypothyroidism are parameters involved in tooth agenesis.
本研究旨在探讨唐氏综合征患者的牙齿缺失（少牙症和非少牙症）、上颌尖牙阻生和牙齿易位的模式，并确定先天性心脏病和甲状腺功能减退症是否为牙齿缺失的参数。
本研究纳入了 114 例唐氏综合征患者。使用标准化记录、临床检查、全景片和单独的 X 光片对数据进行量化。将患者分为少牙症（缺失 6 颗或更多牙齿）和非少牙症（缺失 5 颗或更少牙齿）。
在这些唐氏综合征患者中，有 59.6%的患者有缺牙。非少牙症组中，先天性心脏病与缺失呈负相关趋势（P=0.093；比值比=0.49），但甲状腺功能减退症与缺失呈轻微正相关（P=0.060；比值比=3.71）。在少牙症组中，存在另一种表型的数量和质量上不同的模式。当下颌中切牙均缺失时，少牙症的发生几率显著增加（P=0.001；比值比=38.8）。在下颌中，非少牙症组的犬齿和侧切牙对称性缺失更为常见。
少牙症（具有不同的表型）和非少牙症组的缺失模式不同。上颌尖牙阻生与侧切牙缺失无关。下颌中切牙均缺失是少牙症的高度预测因素。先天性心脏病和甲状腺功能减退症是牙齿缺失的相关参数。
