Occlusal characteristics in 3-year-old children – results of a birth cohort study

BACKGROUND: Aim of this prospective study was to determine prevalence of malocclusion and associated risk factors in 3-year-old Thuringian children. METHODS: Subjects (n = 377) were participants in a regional oral health programme, a birth cohort study with the aim to prevent caries (German Clinical Trials Register DRKS00003438). Children received continuous dental care since birth. Occlusal characteristics (overjet, overbite, anterior open bite, canine relationship and posterior crossbite) were measured at the age of 3 years by one calibrated clinician using a vernier caliper (accuracy 0.1 mm; Münchner Modell 042-751-00, Germany). A regular parent survey was conducted to assess risk factors for development of malocclusion. RESULTS: Three hundred seventy seven children (mean age 3.31 ± 0.70 years; 52.5 % male) were examined. Children had a mean overjet of 2.4 ± 0.8 mm and the mean overbite was 0.8 ± 1.2 mm; 58.8 % of the children had a normal overjet ≤3 mm and 88.8 % a normal overbite with < [Formula: see text] overlap. Prevalence of malocclusion was 45.2 % (10.9 % anterior open bite, 41.2 % increased overjet ≥3 mm, 40.8 % Class II/III canine relationship, 3.4 % posterior crossbite). All children who sucked the thumb had a malocclusion. Children who used a pacifier had greater odds of having a malocclusion at age of 3 years than children without pacifier use (OR = 3.36; 95 % CI: 1.87–6.05). Malocclusion and dental trauma were associated, but not statistically significant (OR = 1.83; 95 % CI: 0.99–3.34; p = 0.062). Malocclusion was not associated with gender, migration background, low socioeconomic status, preterm birth, special health care needs, breathing or dietary patterns (p > 0.05). CONCLUSIONS: Non-nutritive sucking habits were important risk factors for development of a malocclusion in the primary dentition.