Genotype and malocclusion in patients with osteogenesis imperfecta

Structured Abstract Objects To investigate the relationship between genotype and severity of malocclusion in osteogenesis imperfecta ( OI ). Setting and Sample Population A total of 49 patients participated in this cross‐sectional study (age range: 5‐19 years; 28 females; diagnoses: OI type I, N = 7; OI type III , N = 11; OI type IV , N = 27; OI type V, N = 2; OI type VI , N = 2). Materials and Methods Sequence analysis of COL 1A1 / COL 1A2 and other OI ‐related genes was compared to the Peer Assessment Rating ( PAR ), an index reflecting the severity of malocclusion. Results The mutation spectrum was as follows: COL 1A1 , N = 22; COL 1A2 , N = 22, IFITM 5 , N = 2; SERPINF 1 , N = 2; no mutation detected, N = 1). Compared to patients with COL 1A1 mutations, patients with COL 1A2 mutations had significantly higher scores for total PAR , anterior cross‐bite, anterior open bite and anteroposterior buccal occlusion. Males with COL 1A2 mutations had significantly higher total PAR scores than females (median 36 vs 30, P  = .047, Mann‐Whitney test). Exploratory correlation between age and buccal vertical occlusion was noted in patients with COL 1A2 mutations (Spearman correlation: r  = .46, P  = .03, power = .50). Two patients with OI type V (caused by IFITM 5 mutations) had total PAR scores of 44 and 21. Both patients scored high for “segment.” Patients with OI type VI (due to SERPINF 1 mutations) scored similar to OI type V for “centreline.” Considerable difference was observed in the total PAR score between the 2 patients with OI type VI . They had total PAR of 43 and 2. Conclusion Type of disease‐causing mutation affects the severity of malocclusion in individuals with OI .