Indiana University-Purdue University Indianapolis (IUPUI) / Molar Hypomineralization (MH) of the first permanent molars (FPMs) and the second primary molars (SPMs) is a common developmental defect of enamel, with global prevalence of 14% and 5% respectively. Children with MH represent a special pediatric population because their affected molars have extreme susceptibility to enamel breakdown, decay and tooth sensitivity. Although the problem of MH has been described almost twenty years ago mainly through reports from Europe, there is very little information about the problem from the USA. In this dissertation, MH was explored both from the perspectives of pediatric dentists’ (PDs) and at population level. The majority of the survey respondents perceived MH prevalence to be <10% in their clinical practice (62%). The most cited clinical challenge in managing MH teeth was “long-term success of restorations” (79%). When analyzed individually, responses differed significantly for different demographics and educational characteristics of the respondents (p<0.05). At population level, MH of the FPMs (Molar Incisor Hypomineralization (MIH) cohort: 337 schoolchildren, average age 9 years) and of the SPMs (Hypomineralized Second Primary Molar (HSPM) cohort: 423 schoolchildren, average age 7 years) had prevalence estimates of 13% and 6% respectively. In the MIH cohort, water fluoridation or non-Hispanic Black race/ethnicity was significantly associated with higher collective prevalence of enamel defect (EDs) (P<0.05), but not with the prevalence of MH of the FPMs. In the HSPM cohort, race/ethnicity was significantly associated with higher overall prevalence of EDs of SPMs, but not with the HSPM prevalence. Older age group (>10 years), living in central Indiana, and water fluoridation were significantly associated with higher overall prevalence of EDs (P<0.01), but not with the HSPM prevalence. Caries experience was significantly higher in children with MH of FPMs and/or SPMs than in the group without MH. We concluded that USA pediatric dentists’ respondents were well aware of the MH problem, but demonstrated discrepancies in different aspects of the MH problem. At population level, MIH and HSPM were common presentation with prevalence estimates similar to the global figures. Certain demographic characteristics were significantly associated with the overall prevalence of the enamel defects of the examined teeth.

Molar Incisor Hypomineralization definieras som ett specifikt tillstånd orsakat av störningar i den tidiga fasen av emaljbildning av en eller flera permanenta första molarer med eller utan involvering av permanenta incisiver. Tidigare studier har visat att standardiserad intraoral fotograferingsteknik kan vara användbar för epidemiologiska studier av emaljdefekter. Denna studies syfte var att utveckla och utvärdera en fotografisk klassificering av allvarlighetsgraden av Molar Incisor Hypomineralization genom att studera metodens validitet och reliabilitet. 164, 10-12 åriga svenska barn granskades fotografiskt avseende prevalensen av Molar Incisor Hypomineralization. Först granskades endast första molarens ocklusalyta, därefter ocklusal- och buckalyta. Granskningarna jämfördes sedan med en tidigare utförd klinisk registrering, baserad på etablerade kriterier. Den fotografiska metodens validitet och reliabilitet beräknades. Vid beräkning av validiteten framgick att överensstämmelsen mellan den fotografiska och kliniska registreringen låg mellan 82-84 % på individnivå. Sensitiviteten för den fotografiska diagnostiken av ocklusalytorna var 48 % och specificiteten 95 %. Motsvarande siffror då buckalytorna inkluderades var 73 % och 88 %. Metodens reliabilitet resulterade i Cohens Kappa koefficienter som motsvarade ”moderat” och ”good” inom Kappa statistiken. Fotografisk klassificering bedöms användbar för diagnostisering av molar incisor hypomineralization, förutsatt att registreringen föregås av noggrann diagnostisk träning och kalibrering. / Molar Incisor Hypomineralization is defined as a specific condition caused by disturbance in the early phase of enamel formation in one or more of the permanent first molars, with or without the involvement of permanent incisors. Previous studies have shown that standardized intraoral photographic technique can be useful in epidemiological studies of enamel defects. The aim of this study was to develop and evaluate a photographic classification of the severity of Molar Incisor Hypomineralization by studying the validity and reliability of the methods. 164, 10 – 12 year old Swedish children were examined photographically for Molar Incisor Hypomineralization prevalence. The first examination only included the occlusal surface of the first molars, thereafter the occlusal and the buccal surfaces were examined. The findings from the photographical examinations were compared to a previously performed clinical registration, based on recognized criteria. The photographical method´s validity and reliability was calculated. The agreement between the photographic and the clinical examinations varied between 82-84 % on individual level. The sensitivity for the photographic examination of the occlusal surface only, was 48% and the specificity 95%. Corresponding results for occlusal and buccal surface were 73% and 88%. The reliability of the method, calculated using the Cohens Kappa coefficient, was judged as “moderate” to “good”. The photographic diagnostic method seems to be useful for diagnosis of Molar Incisor Hypomineralization. However, careful diagnostic training and calibration prior to registration is necessary.

Background: Treatment of oral diseases can have a long-lasting impact on a child’s life well beyond its childhood years. The purpose of this study was to compare the impact of treatment on the oral-health-related quality of life (OHRQoL) of children with severe caries and severe molar incisor hypomineralization (MIH). Methods: A total of 210 children (mean age 9 years; 49% female) with severe caries (inner third of dentin) and severe MIH (post-eruptive breakdown, crown destruction) were included in the study. Both groups were matched according to age, gender, and social status. The German version of the Child Perception Questionnaire for 8–10-year-olds (CPQ-G8–10) was used before and after treatment to analyze the impact on OHRQoL. Results: Patients with severe MIH showed a significantly higher total CPQ score (17.8 (±10.6)) before treatment compared to the caries group (13.8 (±14.3)). The mean CPQ score in all subdomains decreased significantly after therapy in the MIH group. Children with severe carious lesions had similar results except in the domain “functional limitations”, as treatment led to only minor changes (2.9 (±3.6) to 2.2 (±2.6)). Conclusions: Despite a narrower treatment spectrum, patients with severe MIH experienced a greater overall improvement in OHRQoL compared to the caries group.

Background: Molar–incisor hypomineralization (MIH) has a strong negative effect on oralhealth-related quality of life (OHRQoL). Malformed teeth can be hypersensitive, and the discoloration might affect children’s appearances, reducing their well-being. The purpose of the study was to investigate how hypomineralized incisors and molars differ in children’s perceived OHRQoL. Materials and Methods: 252 children aged 7–10 years old were included and subdivided into three equal groups (n = 84). Group A included children with asymptomatic molars and affected incisors. Group B included children presenting only affected molars. Group C was the control group, with children showing no MIH. All participants were asked to complete the German version of the Child Perceptions Questionnaire (CPQ-G8-10) to measure OHRQoL. Results: Participants in the posterior group showed a median total CPQ of 13.4 (±1.7), which was significantly higher than scores in the anterior and control group, which showed a median total CPQ of 8.4 (±1.4) and 4.2 (±0.7), respectively. Children in the posterior group suffered more from oral symptoms and functional limitations, whereas the anterior group dealt more with social and emotional well-being problems. Conclusions: The position of the MIH-affected teeth causes different influences on perceived OHRQoL.