Cost-effectiveness of restorative treatments for permanent molars with severe molar incisor hypomineralization: perspectives for the Brazilian public health system.

OBJECTIVES: To undertake a cost-effectiveness analysis of restorative treatments for a first permanent molar with severe molar incisor hypomineralization from the perspective of the Brazilian public system. MATERIALS AND METHODS: Two models were constructed: a one-year decision tree and a ten-year Markov model, each based on a hypothetical cohort of one thousand individuals through Monte Carlo simulation. Eight restorative strategies were evaluated: high viscosity glass ionomer cement (HVGIC); encapsulated GIC; etch and rinse adhesive + composite; self-etch adhesive + composite; preformed stainless steel crown; HVGIC + etch and rinse adhesive + composite; HVGIC + self-etch adhesive + composite, and encapsulated GIC + etch and rinse adhesive + composite. Effectiveness data were sourced from the literature. Micro-costing was applied using 2022 USD market averages with a 5% variation. Incremental cost-effectiveness ratio (ICER), net monetary benefit (%NMB), and the budgetary impact were obtained. RESULTS: Cost-effective treatments included HVGIC (%NMB = 0%/ 0%), encapsulated GIC (%NMB = 19.4%/ 19.7%), and encapsulated GIC + etch and rinse adhesive + composite (%NMB = 23.4%/ 24.5%) at 1 year and 10 years, respectively. The benefit gain of encapsulated GIC + etch and rinse adhesive + composite in relation to encapsulated GIC was small when compared to the cost increase at 1 year (gain of 3.28% and increase of USD 24.26) and 10 years (gain of 4% and increase of USD 15.54). CONCLUSION: Within the horizon and perspective analyzed, the most cost-effective treatment was encapsulated GIC restoration. CLINICAL RELEVANCE: This study can provide information for decision-making.

Gingival proteomics reveals the role of TGF beta and YAP/TAZ signaling in Raine syndrome fibrosis.

Raine syndrome (RNS) is a rare autosomal recessive osteosclerotic dysplasia. RNS is caused by loss-of-function disease-causative variants of the FAM20C gene that encodes a kinase that phosphorylates most of the secreted proteins found in the body fluids and extracellular matrix. The most common RNS clinical features are generalized osteosclerosis, facial dysmorphism, intracerebral calcifications and respiratory defects. In non-lethal RNS forms, oral traits include a well-studied hypoplastic amelogenesis imperfecta (AI) and a much less characterized gingival phenotype. We used immunomorphological, biochemical, and siRNA approaches to analyze gingival tissues and primary cultures of gingival fibroblasts of two unrelated, previously reported RNS patients. We showed that fibrosis, pathological gingival calcifications and increased expression of various profibrotic and pro-osteogenic proteins such as POSTN, SPARC and VIM were common findings. Proteomic analysis of differentially expressed proteins demonstrated that proteins involved in extracellular matrix (ECM) regulation and related to the TGFß/SMAD signaling pathway were increased. Functional analyses confirmed the upregulation of TGFß/SMAD signaling and subsequently uncovered the involvement of two closely related transcription cofactors important in fibrogenesis, Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). Knocking down of FAM20C confirmed the TGFß-YAP/TAZ interplay indicating that a profibrotic loop enabled gingival fibrosis in RNS patients. In summary, our in vivo and in vitro data provide a detailed description of the RNS gingival phenotype. They show that gingival fibrosis and calcifications are associated with, and most likely caused by excessed ECM production and disorganization. They furthermore uncover the contribution of increased TGFß-YAP/TAZ signaling in the pathogenesis of the gingival fibrosis.

Knowledge and perception regarding molar incisor hypomineralisation among dental students and dental hygienist students in Spain: a cross-sectional study.

BACKGROUND: Molar incisor hypomineralisation (MIH) has a high prevalence in the Spanish pediatric population and is a precursor of carious lesions in teeth in which it is present. Although this pathology is included in the curricula of the Degree in Dentistry and the Training Cycle in Oral Hygiene in our country, the contents currently taught seem to be insufficient in relation to the level of knowledge that we have today about this condition. METHODS: A digital questionnaire of 18 questions was sent to a sample of 448 students attending the 4th and 5th year of the Degree in Dentistry and 2nd year of the Training Cycle in Oral Hygiene from different universities and vocational training centers in the Valencian Community. Descriptive and multivariate statistical analysis of the data was subsequently performed. RESULTS: Of the 290 questionnaires that were obtained, 53.8% were from students attending the 2nd year of a training course in oral hygiene and 46.2% were from students pursuing a degree in dentistry. Most of the respondents had heard about MIH (75.2%), mainly through master classes. However, most students had difficulties distinguishing MIH lesions from other lesions (58.3%). The degree of knowledge about MIH was greater among dental students in all the aspects evaluated: prevalence, diagnosis, prevention, and treatment. Of all the students, 83.8% were interested in increasing their training on MIH, especially in the areas of diagnosis and treatment. CONCLUSION: The results of the present study justify the need to expand the content on MIH, both theoretical and practical, in the educational curricula of the Degree in Dentistry and Integrated Vocational Training Centers in Spain.

Prenatal exposure to environmental toxins and comprehensive dental findings in a population cohort of children.

Environmental toxins are known to have many impacts on growth and development in humans, starting in utero. Alterations in amelogenesis, caused by chemical and physical trauma that occur during the antenatal, perinatal and postnatal time periods, may result in developmental defects in deciduous and permanent tooth enamel, as demonstrated in animal studies. These defects can be clinically visible and result in a variety of morphological and functional problems in the dentition. Since enamel does not remodel after formation, it may serve as a permanent record of insults during organ development.Our primary purpose was to investigate any possible relationship between intrauterine exposure to endocrine disrupting chemicals (phenols and phthalates) and developmental defects in enamel in children, while also accounting for fluoride exposure. Our secondary purpose was to report descriptively on findings from comprehensive dental examinations performed on 356 children that were drawn from the general paediatric population. A cohort of children from the Utah Children's Project (N = 356) that had full medical exams, comprehensive medical and family histories and available biospecimens were given extraoral and intraoral examinations. They also completed an oral health questionnaire. Standardized intraoral photographs were taken of the teeth and viewed by standardised examiners and the dental observations were recorded for a full inventory of findings, including: tooth morphology, caries, restorations, colorations, attrition, erosion, fractures and hypomineralization. Perinatal maternal urine samples were assessed for the concentration of fluoride, phenols and phthalates, including bisphenol A (BPA).Pairwise statistical analyses were done to correlate the dental findings with one another and with the presence of environment chemicals found in the urine samples. Hypomineralization was the most common finding (96% of children; 37% of deciduous teeth, 42% of permanent teeth), consistent with molar incisor hypomineralization (MIH) described in other human populations. No consistent correlations were seen between dental findings and the presence of phenols and phthalates in prenatal urine, but the number of samples available for the assessment was limited (n = 35).In conclusion, we found a high proportion of dental hypomineralization in a population based paediatric cohort, but did not find an association with prenatal exposure to phenols and phthalates.

Clinical performance of short fiber reinforced composite and glass hybrid on hypomineralized molars: A 36-month randomized split-mouth study.

OBJECTIVES: This study aimed to assess the clinical performance outcome at 36 months of molars with molar incisor hypomineralization and carious lesions, treated with two different restorative approaches following selective caries removal. METHODS: The children aged 6 to 12 years (18 female, 13 male) included in the study had at least two carious permanent first molars diagnosed with molar incisor hypomineralization. Sixty-two molars were restored in a split-mouth design. In all subjects, selective caries removal was performed so that caries was completely removed from the cavosurface walls and only soft dentin was left above the pulp chamber. Short fiber reinforced composite (SFRC; EverX Flow™) covered by micro-hybrid composite (G-Aenial® posterior composite) and Glass Hybrid (GH; Equia Forte® HT) were used as restorative materials. The restorations were evaluated according to modified United States Public Health Service (USPHS) criteria at baseline, 6, 12, 18, 24, and 36 month follow-ups. RESULTS: During the 36-month follow-up, eight GH and four SFRC restorations failed. The clinical success of both restorations decreased statistically over time (p < 0.001 for both). When variables such as restoration type, sex, age, tooth type, and time were included in the model, the risk of failure of the restorations of the left lower first molar was statistically significantly higher than that of the left upper first molar (p < 0.002). CONCLUSION: Direct composite restorations with SFRC and GH restorations perform similar clinical success with selective caries removal in the management of permanent molars affected by molar incisor hypomineralization. CLINICAL SIGNIFICANCE: SFRC or GH restorations with similar clinical success might be preferred for the management of MIH-affected molars.

Does information about MIH on dental homepages in Germany offer high quality? A systematic search and analysis.

PURPOSE: The internet is increasingly used to seek health information. A dental condition of increasing concern and public interest is molar incisor hypomineralisation (MIH), why we evaluated the information quality of German dentists 'websites on the topic of MIH. METHODS: A systematic search was performed by two independent investigators using three search engines. The information content of websites on MIH and technical, functional aspects, overall quality, and risk of bias were assessed using validated instruments (LIDA, DISCERN). Practice-related characteristics (practice type, specialization, setting, number and mean age of dentists) were recorded, and associations of these characteristics with websites' overall quality were explored using multivariable linear regression modelling. RESULTS: 70 sites were included. 52% were multipractices in urban areas (49%). The most common age group was middle-aged individuals (41-50 years). The average number of dentists/practice was 2.5. The majority met more than 50% of the DISCERN and LIDA criteria (90%, 91%). The MIH definition was frequently used (67%), MIH symptoms were described (64%), and 58% mentioned therapies. The prevalence of MIH was mentioned less frequently (48%). MIH example photographs were rarely shown (14%). In multivariable analysis, most practice-related factors were not significant for overall site quality. Only chain practices had slightly higher quality in this regard (2.2; 95% CI of 0.3-4.1). CONCLUSIONS: MIH is mentioned on a large proportion of dentists' websites. Overall technical, functional, and generic quality was high. Risk of bias is limited. While most websites provided a basic definition of MIH and its symptoms, important information for patients was missing.

Treatment choice for first permanent molars affected with molar-incisor hypomineralization, in patients 7-8 years of age: a questionnaire study among Swedish general dentists, orthodontists, and pediatric dentists.

PURPOSE: The aim of this study was to investigate attitudes and preferred therapy choice for first permanent molars (FPM) with Molar-Incisor Hypomineralization (MIH). METHODS: An online questionnaire was sent out to general dentists (n = 559) working in the Public Dental Service in Region Västra Götaland, orthodontists (n = 293), and pediatric dentists (n = 156) (members from each interest association), in Sweden. The questionnaire contained three parts: general questions regarding the respondents, patient cases, and general questions regarding extraction of FPMs with MIH. Statistics were carried out using Chi-squared tests, with a significance level of 5%. RESULTS: A response rate of 36% was obtained. Orthodontists and pediatric dentists were more prone to extract FPMs with both moderate and severe MIH, compared to general dentists. When restoring FPMs with moderate MIH, resin composite was preferred. Compared to the general dentists, the pediatric dentists were more prone to choose glass-ionomer cement in the FPMs with severe MIH. The most common treatment choice for FPMs with mild MIH was fluoride varnish. "When root furcation is under development of the second permanent molar on radiographs" was chosen as the optimal time for extracting FPMs with severe MIH, and the general dentists based their treatment decisions on recommendations from a pediatric dentist. CONCLUSION: Extraction of FPMs with moderate and severe MIH is considered a therapy of choice among general dentists and specialists, and the preferred time of extraction is before the eruption of the second permanent molar.

The prevalence of developmental defects of enamel in a cohort of adults with cystic fibrosis - A cross sectional study.

OBJECTIVES: Cystic Fibrosis is an autosomal recessive condition. It is a multisystem disease treated with a broad range of pharmacological therapies, diet and nutrition, and physiotherapy. Previous studies suggest that people with cystic fibrosis have a higher prevalence of developmental defects of enamel which may place this population at a greater risk of developing oral diseases such as caries. The aim of this study was to assess a cohort of people with cystic fibrosis (PwCF) for the presence of developmental defects of enamel and compare the results with a control group of people without cystic fibrosis. METHODS: A cross sectional study involving 92 participants with cystic fibrosis and 92 controls was conducted in Cork University Dental School & Hospital. All participants completed a detailed questionnaire prior to undergoing a full clinical examination. The Developmental Defect of Enamel Index was used as a measurement index. All data was statistically analysed with the help of statisticians from Cystic Fibrosis Registry of Ireland. RESULTS: 64 % (n = 59) of PwCF had enamel defects compared to just 30 % (n = 28) of people without cystic fibrosis. The median number of teeth affected by enamel defects in the study group was 1.5, compared to 0 in the control group. CONCLUSION: In this study the cohort of PwCF had more enamel defects than people without CF. Further research is required to investigate the aetiology of these findings. CLINICAL SIGNIFICANCE: Clinicians should be vigilant after teeth have erupted in PwCF as they may have an increased susceptibility to developmental defects of enamel.

Molar-Incisor Hypomineralisation: Severity, caries and hypersensitivity.

OBJECTIVES: To investigate distribution of affected teeth and severity of molar-incisor hypomineralisation (MIH) in 8-9-year-old children. A second aim was to study association between severity of MIH and hypersensitivity, caries, and affection of incisors and second primary molars (SPM). METHODS: A total of 3013 children in one age cohort participated in a cross-sectional study, of which 851 children were diagnosed with MIH. A majority of these children were re-examined and MIH diagnosis based on the European Academy of Paediatric Dentistry criteria was confirmed in 538 children. The re-examinations were undertaken at the local clinics by one calibrated dentist. Data were tested with bivariate logistic regression analysis. Results were reported using frequencies, proportions, odds ratios (OR) and confidence intervals (CI). RESULTS: Almost half of the children with MIH (46.8 %) had at least one severely affected molar. Incisors were affected in 51.9 % of children with MIH, and the prevalence was higher in children with severe affection (57.4 %, p < 0.01). Among children with MIH, second primary molars were affected in 29.6 %, hypersensitivity in at least one first permanent molar was reported by 25.8 and 30.8 % had caries extending to dentine. Children classified with severe MIH were more likely to suffer from hypersensitivity (OR 5.62, 95 % CI 3.61-8.74) and dentine caries (OR 10.32, 95 % CI 6.46-16.50) than children with mild MIH. CONCLUSION: Prevalence of hypomineralised incisors and SPM were high in the studied children with MIH. Children with severe MIH had higher probability of incisor affection, dentin caries and hypersensitivity. CLINICAL SIGNIFICANCE: This study highlights the importance of understanding the association between MIH, caries and hypersensitivity, especially in children with severe MIH. These children need extensive and individualized care in the dental services to prevent caries and pain.

"Ethnic disparities in the prevalence of Molar-Incisor-Hypomineralisation (MIH) and caries among 6-12-year-old children in Catalonia, Spain".

AIM: To study the prevalence of MIH and caries in 6- and 12-year-old schoolchildren and their association with ethnic disparities and other relevant factors. BACKGROUND: In recent years, there has been uneven improvement in school children's oral health, highlighting inequalities in access to dental care and health outcomes, particularly among ethnic minorities. The most prevalent oral disease in childhood, caries, is preventable, as its risk factors are well known. However, MIH, a common condition affecting the enamel of permanent incisors and/or molars, has no established aetiology or preventive measures. METHODS: A cross-sectional study among schoolchildren was conducted in 725 children from Masnou (Barcelona, 2013) and in 577 children from Sant Andreu de Llavaneres (Barcelona, 2018-2020). Data collection was carried out by means of clinical examination and a selfreferenced questionnaire. Oral health outcomes included: presence of dental caries, presence of MIH, hypomineralised second primary molars (HSPM). All variables were analysed according to ethnic disparities and other variables such as socioeconomics, diet, hygiene habits, plaque and access to dental services. We performed multivariate Poisson regression models with robust variance to examine ethnic disparities in MIH and caries. CONCLUSION: This cross-sectional study based in Catalonia, Spain showed that there are ethnic disparities in caries as observed with other child's diseases; however, they do not seem to follow the same pattern for MIH. More studies are needed (i) to explore how MIH behaves among populations in terms of inequality; (ii) to study the aetiological factors of MIH; and (iii) to identify potential factors associated with MIH and caries that have not been studied and that may contribute to the observed ethnic disparities.

Caries experience in children with molar-incisor hypomineralisation in Fujairah, United Arab Emirates and its association with hypomineralised teeth number.

BACKGROUND: Molar-incisor hypomineralisation (MIH) has been found associated with an increase in dental caries. Studies utilising the recent MIH diagnosis and calibration criteria recommended by the EAPD in 2021 are very scarce. Additionally, the available data in literature about the relationship between the hypomineralised teeth number (HTN) and caries come from only one study. PURPOSE: To assess the relationship between MIH and caries experience among children in the city of Fujairah, UAE, utilising the recent criteria recommended by the European Academy of Paediatric Dentistry (EAPD) in 2021, and to assess the relationship between the number of teeth affected with MIH, and dental caries. METHODS: One hundred and sixty-two children were included in this cross-sectional study, aged 7-9 years old. Children were examined for MIH according to Ghanim et al. (Eur Arch Paediatr Dent 16:235-246, 2015. 10.1007/s40368-015-0178-8) criteria and Ghanim et al. (Eur Arch Paediatr Dent 18:225-242. 10.1007/s40368-017-0293-92017) training manual. Caries experience was assessed with decayed, missing, filled (dmft, DMFT) scoring system. RESULTS: dmft mean was 6.56 (SD ± 3.78) and DMFT mean was 0.91 (SD ± 1.23). Children with MIH had significantly higher dmft (p = 0.003) scores. Children with higher HTN had significantly higher dmft (p = 0.008) scores. CONCLUSION: Children in Fujairah have extremely high caries scores. Children with MIH have more decayed, missing and filled teeth. Hypomineralised teeth number was positively associated with caries experience.

Prevalence and clinical presentation of molar incisor hypomineralisation among a population of children in the community of Madrid.

OBJECTIVE: The main objective of this study was to estimate the prevalence of molar incisor hypomineralisation (MIH), an alteration of tooth enamel with an estimated worldwide prevalence rate of 14%, among children using primary care services in the Community of Madrid, Spain. MATERIALS AND METHODS: This was a descriptive, cross-sectional and multicentre study. After calibrating all researchers and following the diagnostic criteria of the European Academy of Paediatric Dentistry (EAPD), children aged between 8 and 16 years who were users of the dental services at 8 primary oral health units of the Madrid Health Service (SERMAS) were included. The children underwent a dental examination, and the parents were asked to complete a questionnaire. RESULTS: The prevalence of MIH was 28.63% (CI: 24.61-32.65%). The age cohorts most affected by MIH were 8 years (21.4%) and 11 years (20.7%). The presence of MIH was greater among girls (85; 60.71%) than among boys (55; 39.28%). The mean number of affected teeth per patient was 4.46 ± 2.8. The most frequently affected molar was the upper right first molar (74.3%), and the upper left central incisor was the most affected incisor (37.85%). Opacities were the defects most frequently recorded (63.57%). CONCLUSIONS: The prevalence of MIH in this study is the highest of all relevant studies conducted in Spain.

Selective excavation and ozone therapy: new frontier of mini-invasive caries treatment in MIH paediatric patients. A case report.

BACKGROUND: The term hypomineralisation of molars and incisors (MIH), introduced in 2001 by Weerheijm et al., describes a clinical state of hypomineralisation of permanent molars with frequent involvement of the incisors. MIH is considered a global dental problem with a prevalence ranging from 2.4% to 40.2% in the entire world paediatric population. The continuous increase in the prevalence of enamel anomalies, including MIH, indicates the need to define new intervention protocols based on the technological advances that are revolutionising paediatric dentistry. The use of ozone associated with the selective and minimally invasive excavation of the dental tissue combines the antibacterial properties of the gas with an ultra-conservative approach aimed at the maximum conservation of the dental tissue. The operative protocol described can be an important tool in the prevention and treatment of MIH. The aim of this work is to illustrate an operative clinical protocol based on the combined use of selective excavation and ozone for the treatment of carious lesions in paediatric patients with MIH.

Management of permanent incisors affected by Molar-Incisor-Hypomineralisation (MIH) using resin infiltration: a pilot study.

PURPOSE: To compare the aesthetic improvement of Molar-Incisor-Hypomineralisation (MIH) opacities treated by applying Icon-Etch for three cycles with the opacities treated by Icon-Etch for once, in the course of resin infiltration technique. METHODS: Thirty incisors were sorted based on the colour of the opacities and then distributed according to the number of Icon-Etch cycles using a randomisation table into the groups: (1) White/Creamy one cycle, (2) White/Creamy three cycles, (3) Yellow/Brown one cycle, (4) Yellow/Brown three cycles. The primary outcomes of applying the resin infiltration to the opacities were compared amongst groups according to the parents' satisfaction, the amount of coverage, and the colour matching with the surrounding sound enamel. The stability of the results after 3 months was evaluated using a spectrophotometer. RESULTS: The colour of the opacity pre-treatment affected the outcomes significantly (p < 0.05), compared according to the method of application (p > 0.05) in terms of parents' satisfaction. Whilst the multiple applications for Icon-Etch cycles showed more coverage amount in White/Creamy opacities than the application ones (p < 0.05); in colour matching, there was no statistically significant difference between the two methods (p > 0.05). For yellow/brown opacities, some negative results occurred with the single Icon-Etch cycle. CONCLUSION: In MIH opacities, it is possible to rely on the resin infiltration as a minimally invasive method to achieve acceptable results, especially with multiple Icon-Etch cycles applications in the white/creamy opacities. The colour stability has not been affected by either the colour of the opacity or the number of cycles.

Molar incisor hypomineralization and oral health-related quality of life: a sample of 8-12-years-old children.

OBJECTIVES: The study aimed to evaluate the impact of molar incisor hypomineralization (MIH) and tooth sensitivity on the oral health in terms of the quality of life (OHRQoL). In addition, the impact of tooth maturity on tooth sensitivity was evaluated in the study. MATERIALS AND METHODS: Children aged 8-12 years with and without MIH participated in this descriptive cross-sectional study. They were chosen through the convenience sample technique. The Pediatric-Oral-Health-related-Quality-of-Life (POQL) scale was used to assess OHRQoL. The presence of the MIH and decayed, filled and missing teeth due to caries (using dmft/s, DMFT/S indexes) were recorded. The tooth sensitivity and dental maturity status were evaluated with the Shiff-Cold-Air-Sensitivity-Scale (SCASS) and Demirjian-method, respectively. Statistical analysis of the data was performed by Pearson Chi-Square Test and Mann-Whitney U test (p<0.05). RESULTS: In this study, the participants were a total of 260 children, half were affected by the MIH. Their mean POQL scores were higher than those of the children without MIH with a statistically significantly difference in the total child scale score (p=0.014). Among the children with the MIH, child total QoL score was found to be higher in SCASS positive response group (p=0.011). The teeth with MIH (p<0.001) showed higher response to the stimulus. According to the dental age and dental maturity categories of the children with MIH, the total child scale score was found to be higher in the SCASS category (p=0.011), and the response status to the SCASS was statistically significant (p=0.042 and p=0.05, respectively). CONCLUSIONS: Among the children with MIH, the OHRQoL was found to be negatively affected. The teeth with the MIH tend to reveal more tooth sensitivity than healthy teeth. Many conditions such as having MIH, and tooth sensitivity might have an impact on the OHRQoL. In addition, more sensitivity to the stimulus was observed in the teeth with lower tooth maturity status; the dental age and dental maturity might have effects on tooth sensitivity. CLINICAL RELEVANCE: Considering the negative impacts due to MIH, the evaluation of OHRQoL is critical for dentists to employ a well-defined guide in their clinical decisions.

Is there a rise of prevalence for Molar Incisor Hypomineralization? A meta-analysis of published data.

Since Molar Incisor Hypomineralization was first described as a pathologic entity, public perception often suggests a considerable rise in prevalence of the respective disease. Since there are still considerable doubts regarding the etiology and-accordingly-prevention of MIH and respective therapeutic approaches are difficult this question is of considerable clinical and public interest. Accordingly, a systematic literature search in accordance with the PRISMA guidelines for systematic reviews on Medline, Cochrane Database, EMBASE, LILACS, Web of Science, Google scholar, Scopus was performed to retrieve original articles reporting the prevalence of MIH as defined by the European Academy of Pediatric Dentistry (EAPD). From initially 2360 retrieved titles, 344 full texts were assessed for possible inclusion and finally 167 articles of mainly moderate to high quality and based on data of 46'613 individuals were included in the meta-analysis. All studies published before 2001 had to be excluded since it was not possible to align the findings with the EAPD classification. Studies varied considerably regarding cohort size (25 to 23'320, mean 1'235)) and age (5.6-19 y, mean 9.8 y). Over all studies, the weighted mean for the prevalence for MIH was 12.8% (95% CI 11.5%-14.1%) and no significant changes with respect to either publication year or birthyear were found. A sub-analysis of eleven studies reporting on the prevalence in different age groups, however, revealed strong evidence for an increasing prevalence between the years 1992 (3%) and 2013 (13%).Therefore, based on data from cross-sectional studies a possible rise in prevalence of MIH remains unclear. Future prospective large-scale studies under standardized examination conditions with an emphasis on examiner calibration are needed to gain better understanding in the evolution of the prevalence of MIH.

Development of undergraduate students' diagnostic accuracy for the classification of molar incisor hypomineralization.

INTRODUCTION: One of the major difficulties with respect to molar incisor hypomineralization (MIH) is its classification and differentiation from other enamel development defects (EDDs). The aim of this study was to evaluate diagnostic accuracy in dental students to classify MIH as well as its differentiation from other EDDs by combining conventional theoretical classes and e-learning-assisted pre-clinical practices. METHODS: In this one-group pre-test and post-test study, 59 second-year students assessed 115 validated photographs using the MIH Index on the Moodle learning platform. This index assesses the clinical features and extent of MIH, differentiating it from other EDDs. Students received automatic feedback after the pre-test. Two weeks later, students re-evaluated the same photographs. Both pairwise accuracy and overall diagnostic accuracy were estimated and compared for pre- and post-testing, with the area under the curve AUC, along with 95% confidence intervals (95% CI). RESULTS: The lowest diagnostic accuracy was for the ability to discriminate between white or cream-coloured demarcated opacities and hypomineralization-type defect that is not MIH. The overall pre-test accuracy was AUC = 0.83 and increased significantly post-test to AUC = 0.99 (p < .001). The overall accuracy to discriminate the extent of the lesion also increased significantly post-test (p < .001). CONCLUSION: Diagnostic skills to classify MIH can be developed by combining conventional theoretical classes and e-learning-assisted pre-clinical practices.

Effect of photobiomodulation on the efficacy of anesthesia in maxillary permanent molar teeth with molar incisor hypomineralization: A randomized clinical trial.

BACKGROUND: Difficulty in anesthetizing teeth that have been diagnosed with molar incisor hypomineralization (MIH) is a frequently reported clinical problem. The effects of low-level laser application (photobiomodulation) on the efficacy of anesthesia during the dental treatment of patients with MIH have not yet been studied. AIM: To assess the effects of photobiomodulation therapy (PBMT) on the efficacy of anesthesia in maxillary permanent molar teeth with MIH. DESIGN: This prospective, parallel-arm control, randomized, triple-blind clinical trial included children aged 7-12 years. Maxillary permanent first molar teeth with MIH that required pulpotomy treatment were included. Seventy participants were randomly divided into two groups: experimental (with PBMT) and control (placebo). In the experimental group, before the administration of local infiltration anesthesia, PBMT (diode laser: 940 nm; continuous mode; 0.5 W; 78 J/cm2) was applied to the oral mucosa for 60 s each. In the control group, the laser probe was channeled toward the mucosa but was not activated. Pain scores were evaluated during the access cavity preparation of the pulpotomy treatment (when using the dentin cutting handpiece and while entering into the pulp) using the Face, Legs, Activity, Cry, Consolability (FLACC) scale. Additional anesthesia requirements were assessed in both groups. The data obtained were analyzed for statistical significance (p < .05). The chi-squared test was used to determine the effect of PBMT on categorical outcomes. RESULTS: The no-pain scores of the experimental group were higher than those of the control group (29% vs. 20%). Moderate-to-high pain was more frequent in the control group than in the experimental group (43% vs. 20%). While 31% of the experimental group required supplemental anesthesia, 49% of the control group required supplemental anesthesia during pulpotomy of the tooth with MIH. No statistical difference, however, was found between the two groups in terms of pain scores and the need for supplemental anesthesia (p = .235, p = .143). CONCLUSIONS: Anesthesia with and without PBMT caused no difference in pain during the treatment of maxillary molar teeth with MIH.

Predictors of Developmental Defects of Enamel in Primary Maxillary Central Incisors Using Bayesian Model Selection.

INTRODUCTION: Localized non-inheritable developmental defects of tooth enamel (DDE) are classified as enamel hypoplasia (EH), opacity (OP), and post-eruptive breakdown (PEB) using the enamel defects index. To better understand the etiology of DDE, we assessed the linkages amongst exposome variables for these defects during the specific time duration for enamel mineralization of the human primary maxillary central incisor enamel crowns. In general, these two teeth develop between 13 and 14 weeks in utero and 3-4 weeks' postpartum of a full-term delivery, followed by tooth eruption at about 1 year of age. METHODS: We utilized existing datasets for mother-child dyads that encompassed 12 weeks' gestation through birth and early infancy, and child DDE outcomes from digital images of the erupted primary maxillary central incisor teeth. We applied a Bayesian modeling paradigm to assess the important predictors of EH, OP, and PEB. RESULTS: The results of Gibbs variable selection showed a key set of predictors: mother's prepregnancy body mass index (BMI); maternal serum concentrations of calcium and phosphorus at gestational week 28; child's gestational age; and both mother's and child's functional vitamin D deficiency (FVDD). In this sample of healthy mothers and children, significant predictors for OP included the child having a gestational period >36 weeks and FVDD at birth, and for PEB included a mother's prepregnancy BMI <21.5 and higher serum phosphorus concentration at week 28. CONCLUSION: In conclusion, our methodology and results provide a roadmap for assessing timely biomarker measures of exposures during specific tooth development to better understand the etiology of DDE for future prevention.

Why orthodontists need to know about molar incisor hypomineralization.

Molar incisor hypomineralization (MIH) is a systemic developmental qualitative defect of the enamel that affects 1-4 first permanent molars with or without incisor involvement. Enamel hypomineralization is identified visually as a demarcated opacity with a clear border with varying extensions and can be white, yellow, or brown. This opacity is characterized by a reduced quality of enamel that is of normal thickness but not fully mineralized. It is very common for the affected teeth to present with posteruptive breakdown, making them susceptible to caries, leading to their subsequent loss. Thus, MIH is a significant dental problem with clinical, economic, and psychosocial implications. The planned extraction of compromised teeth is a valid alternative to complex restorative treatment. Orthodontists' involvement is essential in developing effective treatment strategies for children affected by MIH, contributing to their oral health and well-being.