Genetic polymorphisms associated with developmental defects of enamel: A systematic review.

BACKGROUND: Polymorphisms in genes related to enamel formation and mineralization may increase the risk of developmental defects of enamel (DDE). AIM: To evaluate the existing literature on genetic polymorphisms associated with DDE. DESIGN: This systematic review was registered in the PROSPERO (CRD42018115270). The literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and in the gray literature. Observational studies assessing the association between DDE and genetic polymorphism were included. The Newcastle-Ottawa Scale was used to assess the risk of bias. RESULTS: One thousand one hundred and forty-six articles were identified, and 28 met the inclusion criteria. Five studies presented a low risk of bias. Ninety-two genes related to enamel development, craniofacial patterning morphogenesis, immune response, and hormone transcription/reception were included. Molar-incisor hypomineralization (MIH) and/or hypomineralization of primary second molars (HPSM) were associated with 80 polymorphisms of genes responsible for enamel development, immune response, morphogenesis, and xenobiotic detoxication. A significant association was found between the different clinical manifestations of dental fluorosis (DF) with nine polymorphisms of genes responsible for enamel development, craniofacial development, hormonal transcription/reception, and oxidative stress. Hypoplasia was associated with polymorphisms located in intronic regions. CONCLUSION: MIH, HPSM, DF, and hypoplasia reported as having a complex etiology are significantly associated with genetic polymorphisms of several genes.

Restorative Techniques for Permanent First Molars Affected by Hypomineralization: A Systematic Review.

Purpose: There are several restorative modalities for molar hypomineralization, but there is no consensus on the best approach. The purpose of this review was to describe restorative approaches applied to permanent first molars (PFM) with molar hypomineralization (MH). Methods: This review was registered (PROSPERO database CRD42017078336). Searches were conducted in the PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library databases and grey literature. From a total of 1,751 studies, 12 that compared restorative treatments for PFM with MH were included. The risk of bias of the studies was assessed using the Cochrane Collaboration and the Newcastle-Ottawa Scale. The success rate was the primary outcome. Results: The restorative treatment options were direct restorations with amalgam, glass ionomer cement, and resin-based composite as well as indirect restorations with stainless steel, porcelain, ceromer, and gold crowns. The restorative techniques, considering the type of isolation and the removal of caries and hypomineralization, vary between the study. There was also a lack of standard clinical criteria for restorative evaluation. The follow-up period ranged from six to 216 months. The success of direct restorations ranged from 86.3 to 100 percent. For indirect restorations, success ranged from 91.3 to 100 percent. Conclusions: There were multiple clinical protocols for MH. The studies presented heterogeneity in the restoration technique, time, and clinical criteria for restorative follow-up. Direct restorations with glass ionomer cement and resin-based composite could be the first choices for restoration. Further randomized clinical trials on a restorative treatment for MH are needed.

A Survival Analysis of Different Pulp Therapies in Decayed Primary Teeth

Abstract Objective: To identify the clinical and radiographic conditions associated with failure of pulp therapy in primary teeth through a survival analysis. Material and Methods: A total of 1000 records of children assisted at the pediatric dentistry clinic of the Federal University of Parana, Brazil, from the years 2000 to 2010, were analyzed. The mean evaluation time was 10.61 months (minimum/maximum: 1/28) from the report of pulp therapy. The different types of treatments analyzed included indirect pulp treatment (IPT), direct pulp treatment (DPT), pulpotomy and pulpectomy. The Kaplan-Meyer method and log-rank test were used for the survival analysis. Exodontia was considered as the outcome variable and censors included: traumatic tooth loss, presence of the tooth in the oral cavity and physiologic tooth exfoliation. Results: A total of 122 records reporting pulp therapy in the primary teeth were selected. From this, 16 teeth (13.12%) were extracted. Survival analysis showed that pulpectomy presented lower survival rates when compared to conservative therapies (p=0.0297). Teeth with furcal lesions and pathological root resorption before pulp therapy had lower survival rates when compared to those that did not present these conditions (P=0.006). Presence of fistula and abscess after pulp therapy were also associated with lower survival rates (P=0.0062 and 0.0143, respectively). Conclusion: Signals of pulp necrosis were associated to lower survival rates in primary teeth submitted to pulp therapy.

Systemic Exposures Associated with Hypomineralized Primary Second Molars.

Purpose: Hypomineralized primary second molars (HPSMs) are clinically represented by demarcated opacities in the enamel, involving from one to four primary second molars. The purpose of this cross-sectional study was to investigate the systemic exposures associated with hypomineralized primary second molars. Methods: A representative population-based sample of 731 eight-year-old children was randomly selected. Data on systemic exposures were collected via a structured questionnaire given to the children's mothers. The HPSMs were clinically assessed by calibrated examiners according to the modified-DDE (developmental defects of enamel) index and European Academy of Paediatric Dentistry criteria. Associations were analyzed by Poisson multiple regression considering a temporal hierarchical approach. Results: The prevalence of HPSMs was 9.4 percent (95 percent confidence interval equals 7.0 to 12.0 percent). Children whose mothers presented with hypertension were found with an Adjusted Prevalence ratio (PRa) of 1.73 (P=0.044) and mothers who used tobacco (PRa equals 2.44; P=0.001) during pregnancy had a significantly higher prevalence of HPSMs. The presence of complications during delivery (PRa equals 1.83; P=0.032) and the occurrence of otitis media during early childhood (PRa equals 1.68; P=0.043) also presented a higher prevalence of HPSMs. Conclusion: The use of tobacco, presence of hypertension, complications during delivery, and otitis media during the first years of a child's life are associated with a higher prevalence of hypomineralized primary second molars. (Pediatr Dent 2019;41(5):364-70).