Survey of congenitally missing teeth in orthodontic patients in Eastern Bavaria.

This retrospective study examined the occurrence of congenitally missing permanent teeth and the need for dental treatment in the Regensburg University Medical Centre of Eastern Bavaria. Using a dental administration software tool, a total of 1442 patients who presented for orthodontic treatment between 1994 and 2006 were identified. After exclusion of 89 patients with incomplete records, 1353 subjects (635 males and 718 females) remained for analysis. Of these, 1130 had no missing permanent teeth, 52 had cleft lips, 110 had one to two teeth missing, 34 had three to five missing teeth, and 27 had greater than or equal to six missing teeth. The analyses focused on the type and number of missing teeth and on differences in the severity of dental agenesis according to gender and to referrals from various geographic regions around Regensburg. The data were statistically analysed using two-tailed tests. The following teeth were most frequently missing: tooth 35 (5.9 per cent), 45 (5.1 per cent), 22 (4.0 per cent), 12 (3.6 per cent), 15 (3.1 per cent), and 25 (3.0 per cent). No statistically significant difference in gender was found for one to two missing permanent teeth (low degree), hypo- or oligodontia (severe degree), or cleft lip. The odds ratio (OR) of presenting with hypo- or oligodontia compared with no missing teeth was higher among subjects originating from geographic regions outside Regensburg than from those from Regensburg, and it was statistically significantly higher for patients from Passau {OR = 3.53 [95% confidence interval (CI) = 1.18-10.52]} and Landshut [OR = 3.65 (95% CI = 1.22-10.99)]. The high prevalence and severe degree of dental agenesis of permanent teeth found in these groups of patients likely reflects distinct referral patterns for patients originating from geographic regions outside Regensburg. These data reinforce the need for a specialized dental treatment centre with the capacity to adequately serve a large rural area in Eastern Bavaria.