Evaluation of pediatric dentists' knowledge and approaches to tooth discoloration.

In recent years, esthetic expectations have come to the fore in pediatric dentistry, as in every field of dentistry. Therefore, to better meet patients' expectations, the steps taken to determine and improve the current level of knowledge of pediatric dentists on tooth discoloration gain importance. This study aims to measure the knowledge levels of pediatric dentists regarding tooth discoloration. A 33-questioned survey created online was emailed to pediatric dentists between March and December 2021. The first part included four multiple-choice and two open-ended questions regarding demographic characteristics. The second part was to measure the participants' knowledge of tooth discoloration. The last part was to evaluate the clinical approaches of the participants. Participants who agreed to answer all of the questions were included in the study (n = 129). The knowledge levels of the participants were scored according to the accuracy of their answers. The data were statistically analyzed using descriptive statistics and chi-square tests. Of the pediatric dentists who participated in this study, 16.3% had high knowledge, 79.8% had medium knowledge, and 3.9% had insufficient understanding of tooth discoloration. There was no correlation between time since dental school graduation and time spent practicing as a pediatric dentist (p > 0.05). The group with the highest average level of knowledge was the group most frequently encountered with tooth discoloration in the clinic (p ≤ 0.05). On average, pediatric dentists had moderate knowledge of tooth discoloration. The group with the highest average expertise in this field was the group that most frequently encountered and treated tooth discoloration. Information on tooth discoloration due to systemic factors was insufficient. To increase the knowledge level of pediatric dentists about the causes and treatments of tooth discoloration, it may be beneficial to establish training programs during and after specialization education.

Shear bond strength of calcium silicate-based cements to glass ionomers.

BACKGROUND: A shear bond strength between the biomaterial and restorative material is crucial for minimizing bacterial microleakage and ensuring a favorable long-term prognosis for vital pulp therapy. This study aimed to conduct a comparative evaluation of the shear bond strength between calcium silicate-based biomaterials utilized in vital pulp treatment and various glass ionomer cement materials, both with and without the application of adhesive agents. METHODS: A total of 270 acrylic blocks, each featuring cavities measuring 4 mm in diameter and 2 mm in depth, were prepared. Calcium silicate-containing biomaterials (ProRoot MTA, Medcem Pure Portland Cement, and Medcem MTA), following manufacturers' instructions, were placed within the voids in the acrylic blocks and allowed to set for the recommended durations. The biomaterial samples were randomly categorized into three groups based on the restorative material to be applied: conventional glass ionomer cement, resin-modified glass ionomer cement, and bioactive restorative material. Using cylindrical molds with a diameter of 3.2 mm and a height of 3 mm, restorative materials were applied to the biomaterials in two different methods, contingent on whether adhesive was administered. After all samples were incubated in an oven at 37 °C for 24 h, shear bond strength values were measured utilizing a universal testing device. The obtained data were statistically evaluated using ANOVA and post-hoc Tukey tests. RESULTS: The highest shear bond strength value was noted in the Medcem MTA + ACTIVA bioactive restorative material group with adhesive application, while the lowest shear bond strength value was observed in the ProRoot MTA White + Equia Forte HT Fil group without adhesive application (P < 0.05). CONCLUSION: Activa Bioactive Restorative may be considered a suitable restorative material in combination with calcium silicate-based biomaterials for vital pulp treatment. The application of adhesives to calcium silicate-based biomaterials can effectively address the technical limitations.

The osteoinductive potential of different root-end filling materials in a rat femur model

In pediatric dentistry, the enduring success of root-end filling materials employed for the establishment of apical plugs in immature teeth undergoing endodontic intervention is contingent upon their possessing a robust osteoinductive capacity. Hence, the primary objective of this study was to histologically assess the osteoinductive potential of four distinct dental materials, specifically recommended for retrograde filling applications, utilizing an animal hard tissue model. Within the designed experimental model, two bone defects measuring 2 mm in diameter and 2 mm in depth were created in both femurs of a cohort comprising 21 male Wistar albino rats. The first defect in the right femur was left blank as the control group, and Neo MTA Plus was placed in the second defect. The EndoSequence BCRRM Fast Set Putty was placed in the first of the defects on the left femur, and Endo Repair was placed in the second defect. Subjects were sacrificed after 7, 14, and 28 days of follow-up, and sections were examined to assess the degree of inflammation, connective tissue formation, and new bone formation. The data were statistically evaluated with Kruskal‒Wallis and post hoc Dunn's tests using SPSS 12 software. The bone healing levels of the Neo MTA Plus group were significantly higher than those of the other groups in all periods (p < 0.05). Bone organization in all groups decreased over time, and fibrous tissue was enriched. The results of this study demonstrate that NeoMta Plus has superior osteoinductive properties compared to other materials but that EndoSequence and Endo Repair have the potential to be developed.

Does childhood chemotherapy affect mandibular bone structures in a lifetime?

BACKGROUND: Chemotherapy, one of the most important treatment modalities for treating childhood cancers, is a major cause of bone loss in patients and survivors. OBJECTIVES: This study aimed to evaluate mandibular bone structures in childhood cancer survivors (CCSs) by means of fractal dimension (FD) analysis and the Klemetti index (KI), and to compare them with regard to the control group. MATERIAL AND METHODS: In this retrospective study, the panoramic radiographs of 49 CCSs were included as the study group and the panoramic radiographs of 49 cancer-free volunteers were included as the control group. Based on the panoramic radiographs, FD and KI were determined. RESULTS: No significant differences were observed between the study and control groups in terms of mean FD values for regions of interest (ROIs) ROI_1, ROI_2 and ROI_3 (p = 0.750, p = 0.490 and p = 0.910, respectively). The mean FD values for ROI_1 for the study and control groups were 1.08 ±0.18 and 1.07 ±0.14, respectively. The mean FD values for ROI_2 for the study and control groups were 1.11 ±0.13 and 1.09 ±0.13, respectively. The mean FD values for ROI_3 for the study and control groups were 1.15 ±0.14 and 1.15 ±0.15, respectively. Statistically significant differences between the study and control groups were noted only in the distribution of the KI categories (p = 0.015). CONCLUSIONS: Childhood chemotherapy may affect mandibular bone structures during a lifetime. The Klemetti index should be considered a useful clinical diagnostic tool for the examination of mandibular bone structures.

Microbiota of Endodontically Infected Primary and Permanent Teeth.

Purpose: Differences in the endodontic microbiome of permanent and primary teeth during the mixed dentition period are still unknown. The purpose of this study was to examine bacterial diversity in endodontically infected primary and permanent teeth using 16S rRNA gene sequencing and the QIIME 2 (Quantitative Insights Into Microbial Ecology 2) bioinformatics pipeline. Methods: Microbial samples from endodontically infected primary (n equals 15) and permanent (n equals 15) maxillary or mandibular molar teeth were subjected to next-generation sequencing analysis based on examination of the hypervariable V3 to V4 region of the 16S rRNA gene. Statistical analysis was performed using R software. Results: Of 1,664,926 reads and 2,237 operational taxonomic units, 14 phyla, 89 families, and 236 genera were identified. Firmicutes were the most commonly detected phyla in both endodontically infected primary and permanent root canals. Bacteroides and Proteobacteria were more common in primary teeth, whereas Actinobacteria and Verrucomicrobia were more common in permanent teeth. The overall canal microbiota composition was similar in endodontically infected primary and permanent teeth (P=0.338). Conclusions: This study provides a comprehensive assessment of microbiota composition in endodontically infected primary and permanent teeth and gives a deeper insight into the origin of the root canal infections.

The Effects of Mouthwashes on the Color Stability of Resin-Based Restorative Materials / Efecto de los enjuagues orales en la estabilidad del color de materiales restauradores a base de resina

Abstract: Objective: This study investigated the effects of three types of mouthwash on the color stability of three resin-based restorative materials (nanohybrid resin composite, sonic-activated bulk-fill material, and compomer). Materials and Methods: To this end, 120 cylindrical disc specimens were prepared and polished, after which they were incubated in distilled water for 24 hours for post-polymerization. The baseline color values of each specimen were measured with a spectrophotometer, then the specimens were randomly divided into four groups. Following immersion in the mouthwashes for 24 hours, the specimens were rinsed with distilled water and dried before the color measurement was repeated. The values of color change (ΔE₀₀) were subsequently calculated. A two-way analysis of variance and Duncan's post hoc multiple comparison tests were conducted to determine statistically significant differences among the restorative materials. Results: All samples showed discoloration after immersion, albeit some instances of discoloration were imperceptible. In this respect, a statistically significant difference was found among the restorative materials and mouthwashes (p<0.05). Imperceptible ΔE₀₀ values were derived on the nanohybrid resin composite and compomer, but perceptible and acceptable ΔE₀₀ values were detected on the sonic-activated bulk-fill materials (p<0.05). The clinically unacceptable discoloration was observed on the sonic-activated bulk-fill composite immersed in Listerine®. Conclusions: Clinicians should make recommendations based on the potential staining capacity of mouthwashes prescribed for daily use in restorative materials. In this way, the need for renewal of restorations due to discoloration could be avoided.

Resumen: Objetivo: Este estudio investigó los efectos de tres tipos de enjuague bucal en la estabilidad del color de tres materiales de restauración a base de resina (resina nanohíbrida, resina bulk-fill de activación sónica y compómero). Materiales y Métodos: Para ello se prepararon y pulieron 120 muestras de discos cilíndricos, después de lo cual se incubaron en agua destilada durante 24 horas pospolimerización. Los valores de color de base de cada muestra se midieron con un espectrofotómetro, después las muestras se dividieron aleatoriamente en cuatro grupos. Tras la inmersión en los enjuagues bucales durante 24 horas, los especímenes se enjuagaron con agua destilada y se secaron antes de repetir la medición del color. Posteriormente se calcularon los valores de cambio de color (ΔE₀₀). Se llevó a cabo un análisis bidireccional de la varianza y las pruebas de comparación múltiple post hoc de Duncan para determinar las diferencias estadísticamente significativas entre los materiales de restauración. Resultados: Todas las muestras mostraron decoloración después de la inmersión, aunque algunos casos esta fue imperceptible. Se encontró una diferencia estadísticamente significativa entre los materiales de restauración y los enjuagues bucales (p<0,05). Se obtuvieron valores imperceptibles de ΔE₀₀ en el compuesto de resina nanohíbrida y el compómero, pero se detectaron valores perceptibles y aceptables de ΔE₀₀ en la resina bulk-fill activada sónicamente (p<0,05). Se observó una decoloración clínicamente inaceptable en la resina bulk-fill activada sónicamente inmersa en Listerine®. Conclusiones: Los clínicos deben hacer recomendaciones basadas en la capacidad potencial de coloración de los enjuagues bucales prescritos para uso diario en los materiales de restauración. De esta manera, se podría evitar la necesidad de renovar las restauraciones debido a la decoloración.