Abstract: Aim To determine the prevalence of MIH in 8- and 9 year-old children in the city of Kljuc, Bosnia-Herzegovina, and to describe the distribution and severity of the affected teeth.
Materials and methods Study design: All 8- and 9-year-olds (n=104) living in Kljuc (born 2004/2005) were invited to participate, and 103 were examined by a calibrated clinician. Written, informed consent was obtained from all participantsí relatives, as well as a questionnaire designed to assess potential risk indicators. Index teeth were all permanent first molars and incisors (12 teeth). Opacities (>1mm), post eruptive breakdown (PEB), atypical restorations and previous extractions caused by MIH were registered.
Results The prevalence of MIH was 11.7% (n=12), significantly higher for girls than for boys (14.6% vs. 9.7%; p<0.05). The maxillary first molars and incisors were 1.8 (p<0.02) and 2.3 (p<0.05) times more frequently affected than the mandibular ones, respectively. Seven (30%) of the affected molars had opacities, 8 (35%) had PEB and 8 (35%) atypical restorations. No molars had been extracted due to MIH. The use of penicillin due to adenoid infections in the first 5 years was associated with a higher prevalence of MIH (41.7% vs. 19.6%).
Conclusions The prevalence of MIH (11.7%) supports the data previously published from Bosnia-Herzegovina. Girls had higher prevalence of MIH than boys; first molars and incisors in the maxilla were almost twice as often affected as in the mandible. Use of penicillin in the first 5 years was associated with a higher prevalence.