Restorative Therapy of MIH-Affected Molars.

One fourth of teeth affected by molar incisor hypomineralisation (MIH) have required or will require treatment due to pain, sensitivity, or posteruptive breakdown. Restorative treatment becomes necessary in cases of severe MIH, characterized by posteruptive breakdown, which exhibits a wide range of clinical characteristics. Until approximately 20 years ago, all techniques, materials, and research were developed for treating caries lesions, not hypomineralisation. Research attempting to evaluate approaches to MIH treatment is recent and inconclusive. Therefore, there is still insufficient high-quality scientific evidence to establish a definitive clinical protocol for treating this condition. Recommendations based on best clinical practices can be provided rather than conclusions supported by a high level of evidence. To assist in clinical judgment regarding the best treatment strategy, eligible therapeutic options for restoring MIH-affected molars will be presented based on the strength and adhesive potential of the remaining hypomineralised enamel. The literature presents options for restorative materials ranging from direct alternatives such as glass ionomer cement and resin composite, through prefabricated devices, such as stainless-steel crowns and orthobands, to indirect restoration alternatives. However, it is essential to understand the indications of each restorative alternative and to know the restorative techniques, many of which are specifically developed to mitigate the difficulties encountered with the use of conventional techniques. Emphasis will be placed on the importance of adopting a personalized approach to restorative decision-making, considering the philosophy of minimal intervention dentistry and potential benefits for the patient's well-being and the family's needs.

Can the combination of proanthocyanidin and vitamin E or palm oil effectively protect enamel against in vitro erosive and abrasive challenges?

OBJECTIVES: This study aimed to assess the effect of proanthocyanidin, palm oil and vitamin E against erosive and erosive+abrasive challenges in vitro after enamel pellicle formation in situ. METHODOLOGY: Bovine enamel blocks (n=84) were obtained and divided into the following treatment groups: negative control (NC) - deionized water; positive control (PC) - SnCl2/NaF/AmF-containing solution; palm oil (PO); 2% proanthocyanidin (P2); vitamin E (VitE); 2% proanthocyanidin+palm oil (P2PO); and 2% proanthocyanidin+vitamin E (P2VitE). For 5 days, one half of the sample from each group was subjected to erosion and the other half was subjected to erosion+abrasion. The acquired enamel pellicle (AEP) was pre-formed in situ for 30 minutes. The specimens were then treated in vitro with solutions (500 µl, 30s for each group). Subsequently, the blocks were left in the oral cavity for another hour to obtain the modified AEP. The blocks were immersed in 0.5% citric acid (pH=2.5) for 90s, 4×/day. AEP formation and treatment were carried out before the first and third erosive challenges, and after these challenges, abrasive cycles (15s) were performed on half of the samples. Enamel wear was quantified by profilometry and data were analyzed by two-way ANOVA and Tukey's test (p<0.05). RESULTS: All groups showed higher wear when exposed to erosion+abrasion than when exposed to erosion alone (p=0.0001). PO, P2VitE, P2, and P2PO showed enamel wear similar to the PC group, but only PC, PO and P2VitE differed from the NC group. The other groups behaved similarly to NC. CONCLUSION: It was concluded that the combination of proanthocyanidin and vitamin E was effective in reducing wear in the face of in vitro erosive and erosive+abrasive challenges.

What can impact on the presence of carious lesions in first permanent molars? Revisiting the association between MIH and caries.

OBJECTIVE: Assess whether the independent variables (IV) such as number of MIH-affected molars, MIH severity, past caries experience, visible plaque index (VPI), gingival bleeding index (GBI), age, and gender affect the presence of caries lesion (DMF_s) in first permanent molars, considering or not atypical restoration in MIH-affected molars as a previous caries lesion. METHODS: A sample of 476 schoolchildren, aged 6-10 years, were evaluated for MIH and caries diagnosis, using the Severity Scoring System (MIH-SSS) and the International Caries Detection and Assessment System (ICDAS), respectively. From the ICDAS, the DF-s/ D-s and df-s were calculated. The Zero-inflated Negative Binomial Regression was used to evaluate the impact of the IV on the dependent variable, considering or not the restorative component in MIH-affected molars. RESULTS: When the presence of caries was evaluated with the restorative component, age, MIH severity and past caries experience had a significant impact on the dependent variable (R2 = 0.176). Without the restorative component in MIH-affected molars, only age and past caries experience were statistically significant (R2 = 0.167). CONCLUSION: Since in the case of MIH teeth restoration may be attributed to post-eruptive breakdown rather than previous caries lesions, in the present study MIH did not influence the presence of caries lesions in the MIH-affected molars showing that restoration is not an adequate parameter for measuring the historical occurrence of caries. CLINICAL RELEVANCE: The first permanent molars may not necessarily be at an increased risk of caries due to MIH if the etiological factors for caries development are effectively managed.

Can the combination of proanthocyanidin and vitamin E or palm oil effectively protect enamel against in vitro erosive and abrasive challenges?

Abstract Objectives This study aimed to assess the effect of proanthocyanidin, palm oil and vitamin E against erosive and erosive+abrasive challenges in vitro after enamel pellicle formation in situ. Methodology Bovine enamel blocks (n=84) were obtained and divided into the following treatment groups: negative control (NC) - deionized water; positive control (PC) - SnCl2/NaF/AmF-containing solution; palm oil (PO); 2% proanthocyanidin (P2); vitamin E (VitE); 2% proanthocyanidin+palm oil (P2PO); and 2% proanthocyanidin+vitamin E (P2VitE). For 5 days, one half of the sample from each group was subjected to erosion and the other half was subjected to erosion+abrasion. The acquired enamel pellicle (AEP) was pre-formed in situ for 30 minutes. The specimens were then treated in vitro with solutions (500 µl, 30s for each group). Subsequently, the blocks were left in the oral cavity for another hour to obtain the modified AEP. The blocks were immersed in 0.5% citric acid (pH=2.5) for 90s, 4×/day. AEP formation and treatment were carried out before the first and third erosive challenges, and after these challenges, abrasive cycles (15s) were performed on half of the samples. Enamel wear was quantified by profilometry and data were analyzed by two-way ANOVA and Tukey's test (p<0.05). Results All groups showed higher wear when exposed to erosion+abrasion than when exposed to erosion alone (p=0.0001). PO, P2VitE, P2, and P2PO showed enamel wear similar to the PC group, but only PC, PO and P2VitE differed from the NC group. The other groups behaved similarly to NC. Conclusion It was concluded that the combination of proanthocyanidin and vitamin E was effective in reducing wear in the face of in vitro erosive and erosive+abrasive challenges.

Comparison between two molar incisor hypomineralization detection criteria in epidemiological surveys.

BACKGROUND: There is no consensus on which molar incisor hypomineralization (MIH) indices are more suitable for epidemiological surveys. AIM: To compare the operational aspects and diagnostic ability of the MIH index (simplified/MIH_s and extended/MIH_e) with the MIH-Severity Scoring System (MIH-SSS) in classifying and diagnosing MIH. DESIGN: This cross-sectional study assessed the indices in a homogeneous group of 680 6- to 10-year-old schoolchildren in Bauru, Brazil, who had at least one first permanent molar, ensuring consistent conditions. Followed by toothbrushing, the children seated on school chairs were examined by the two calibrated researchers under artificial lighting, using mouth mirror and WHO probe, and chronometer recording the duration of examinations. RESULTS: The prevalence of MIH was 24.7%. The most common characteristic of MIH was demarcated opacity, with a prevalence of 81.7% and 85.45% according to the MIH_s and the MIH-SSS, respectively. A positive association was observed among the MIH_s, the MIH_e, and the MIH-SSS (chi-squared test; p < .01). The MIH-SSS demonstrated a shorter average application time than both versions of the MIH index (ANOVA/Tukey; p < .05). Additionally, fluorosis was found to be the most prevalent among other developmental defects of enamel, with a prevalence of 38.38%. CONCLUSION: All systems effectively diagnosed MIH and its characteristics.