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Glass ionomer cements (GICs) are the common materials employed in pediatric dentistry because of their specific applications in class I restorations and atraumatic restoration treatments (ART) of deciduous teeth in populations at high risk of caries. Studies show a limited clinical durability of these materials. Attempts have thus been made to incorporate nanoparticles (NPs) into the glass ionomer for improving resistance and make it like the tooth structure. An in vitro experimental study was conducted using the required samples dimensions and prepared based on the test being carried out on the three groups with or without the modification of light-cured glass ionomer. Samples were grouped as follows: control group (G1_C), 2% silver phosphate/hydroxyapatite NPs group (G2_SPH), and 2% titanium dioxide NPs group (G3_TiO2). The physical tests regarding flexural strength (n = 10 per group), solubility (n = 10 per group), and radiopacity (n = 3 per group) were performed. The data were analyzed by Shapiro Wilks test, and one-way analysis of variance (one-way ANOVA), and multiple comparisons by post hoc Tukey's test. The p-value of < 0.05 was considered significant. No statistically significant difference was observed between the control group (G1_C) and (G2_SPH) (p = 0.704) in the flexural strength test, however differences were found between G2_SPH and G3_TiO2 groups, ANOVA (p = 0.006); post hoc Tukey's test (p = 0.014). Pertaining to the solubility, G2_SPH obtained the lowest among the three groups, ANOVA (p = 0.010); post hoc Tukey's test (p = 0.009). The three study groups obtained an adequate radiopacity of >1 mm Al, respectively. The resin-modified glass ionomer cement (RMGIC) was further modified with 2% silver phosphate/hydroxyapatite NPs to improve the physical properties such as enhancing the solubility and sorption without compromising the flexural strength and radiopacity behavior of modified RMGIC. The incorporation of 2% titanium dioxide NPs did not improve the properties studied.

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PURPOSE: Fixed restorations and dental enamel have different structures that produce different wear on opposing teeth, resulting in clinical problems. Therefore, it is necessary to determine the type of restoration that causes less wear on naturally opposing teeth to make recommendations. The objective of this study was to systematically analyze the evidence from observational studies and clinical trials on enamel wear in different ceramic restorations. STUDY SELECTION: The designs of the included studies were randomized clinical trials (RTCs), non-randomized clinical trials (non-RTCs), and observational studies (OS). The studies must answer the research question, be available in full text, be written in English or Spanish, and have had at least six months of follow-up. Protocol number: CRD42023397759. RESULTS: After screening 499 records, 20 RTCs were subjected to data extraction, 10 were excluded, 10 were included in the systematic review, and only 5 were included in the network meta-analysis. The risk of bias assessment reported moderate to high risk of bias, quality, and certainty of evidence was evaluated and rated as moderate. Network meta-analysis showed higher enamel wear was observed in natural dental enamel against metal-ceramic antagonists. CONCLUSIONS: Enamel wear occurs in all teeth, even when the antagonist is a natural tooth. The wear is larger on surfaces with the ceramic crown antagonists studied (metal-ceramic, glazed zirconia, and polished zirconia). It is necessary to conduct additional clinical trials with larger follow-up periods and sample sizes.

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Flowable composite resins are materials available for restorations in pediatric dentistry. However, these materials are subject to dangerous effects in the oral environment caused by acids that deteriorate and increase their roughness. Therefore it is important to evaluate the effect of different industrialized acid beverages on the roughness of flowable composite resins. An in vitro experimental study, was done using a convenience sample of 132 discs of 5 mm diameter by 2 mm depth of four flowable materials (FF (Filtek™ Z350 XT Flowable), TNF (Tetric® N-Flow), PF (PermaFlo®) and GF (Grandio® Flow)) exposed to three beverages (CC (Coca-Cola), AJ (apple juice), and FM (fermented milk)) and incubated at 37 ºC for 0, 15 and 30 days. The roughness (average roughness (Ra) and maximum height of profile (Rz) parameters) was measured at different intervals of time with a profilometer. For the data analysis, one-way analysis of variance (one-way ANOVA) and repeated measures analysis of variance (Repeated measures ANOVA) tests were applied (p < 0.05). In the roughness test before immersion, no differences were observed within the groups, with maximum roughness values for Filtek™ Z350 XT Flowable and minimum for PermaFlo®. However, at 15 and 30 days of immersion, the groups showed significant differences depending on the immersion drink, except Grandio® Flow in apple juice and fermented milk. The flowable materials studied presented specific behaviors according to the immersion period and drink used. The Filtek™ Z350 XT Flowable showed a similar increase in surface roughness independently of the drink used. Grandio® Flow was the most stable material against surface roughness changes after beverage immersion.

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BACKGROUND: A good level of knowledge in dentists is crucial for an early diagnosis of oral cancer (OC). In Latin America there are a few studies of OC knowledge among dentist, those has been performed in Brazil, Colombia, and Chile, and their results showed low level of OC knowledge. On the other hand, there is no publication in which the level of knowledge of dentists in Mexico has been addressed. Therefore, this study aimed to assess knowledge of OC and to determine the association of the level of knowledge with sociodemographic characteristics among dentists in Mexico. METHODS: A cross-sectional online survey was designed to obtain information via questionnaire. The questionnaire was developed in the Spanish language, and the content validity was determined. The study was conducted among Mexican dentists with a 23-item questionnaire that was designed to be anonymous. The sample size was calculated using the finite population formula. Based on the responses, the level of knowledge of OC was categorized as very low, low, regular, good, or excellent. Additionally, the association between sociodemographic characteristics and the level of knowledge about OC was evaluated. RESULTS: This research was conducted on a sample of 387 dentists. Most of the respondents were general dentists and worked in urban zones. The majority of dentists lacked a specialty (76.7%). Additionally, most of the respondents were students (44.2%). The level of knowledge of the participants was between regular and good (77.8%). On the other hand, concerning self-evaluation, most of the participants considered their knowledge of OC to be regular (50.6%). In addition, there was no association between sociodemographic characteristics and knowledge about OC. CONCLUSIONS: This research identified some weaknesses in most Mexican dentists' knowledge of OC.

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Background: The use of novel materials as an artificial extracellular matrix for stem cell growth is a current strategy of increasing interest for regenerative medicine. Here, we prepare thermal-remolded membrane scaffolds from poly(3-hydroxybutyrate) grafted with 2-amino-ethyl methacrylate hydrochloride. However, it is unclear whether these membranes are useful for tissue engineering. Results: The mechanical properties, tribology, and morphology of the dense membranes were assessed. The results show that tensile strain at break and roughness of the compressed membrane decrease with increasing graft degree. Moreover, graft copolymer membranes showed lower resistance to scratching, greater degree of swelling and higher brittleness than un-grafted P(3HB) films. Thus, it effectively supports the growth of dermal fibroblast, as demonstrated by epifluorescence microscopy. Conclusions: It is concluded that the developed membrane can be properly used in is the restoration of skin tissue. How to cite: González-Torres M, Sánchez-Sánchez R, Solís-Rosales SG, et al. Poly(3-hydroxybutyrate) graft copolymer dense membranes for human mesenchymal stem cell growth.

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Los dientes pueden presentar trastornos originados por factores externos o hereditarios que afectan su forma. Dens in dente es una anomalía durante el desarrollo que resulta en la invaginación del esmalte y dentina, en la cara lingual o vestibular, que puede extenderse profundamente dentro de la raíz. El talón cuspídeo es caracterizado por la proyección de una cúspide accesoria en el cíngulo de los órganos dentarios anteriores y la superficie oclusal de los posteriores. Se presenta el caso de una niña de 7 años de edad, con dens in dente y talón cuspídeo en el incisivo central superior derecho que provoca interferencia oclusal prematura, sin sintomatología. Se realizó desgaste gradual del talón cuspídeo, con aplicación de fluoruro de sodio. El diagnóstico temprano de anomalías dentales en pacientes pediátricos es la clave para un tratamiento conservador y preventivo para el adecuado funcionamiento masticatorio y estético del paciente (AU)

Teeth may have disorders caused by external or hereditary factors that affect their shape. Dens invaginatus is an anomaly during development that results in invagination of the enamel and dentin, lingual or vestibular surface, which can extend deeply into the root. Talon cusp is characterized by the projection of an accessory cusp in the cingulate area in anterior and occlusal aspects of the posterior teeth. We present a case of a 7 year old girl with dens invaginatus and talon cusp on the maxillary central incisor that causes premature occlusal interference, without symptomatology. The treatment employed were gradual wear of cuspal talon with several applications of sodium fluoride. Early diagnosis in pediatric patients is the key to a conservative and preventive treatment for a proper masticatory and aesthetic functioning of the patient (AU)

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