Examination of surface porosity of current pulp capping materials by micro-computed tomography (micro-CT) method.

When dental pulp is exposed, it must be covered with a biocompatible material to form reparative dentine. The material used, besides being biocompatible, should have an ideal surface structure for the attachment, proliferation and differentiation of dental pulp stem cells. This study aimed to evaluate the porosity of the microstructures of four pulp capping materials using micro-computed tomography (micro-CT). Biodentine, Bioaggregate, TheraCal and Dycal materials were prepared according to the manufacturer's instructions using 2 × 9 mm Teflon molds. A total of 60 samples, 15 in each group, were scanned using micro-CT. Open and closed pores and the total porosity of the microstructures of the materials were assessed. The findings obtained from the study were analyzed via the Kruskal-Wallis test followed by the Mann-Whitney U test. The porosity of Bioaggregate was significantly higher than that of Biodentine, Dycal and TheraCal in all porosity values. While Biodentine did not show a statistically significant difference in open and total porosity values from either TheraCal or Dycal, closed porosity values of Dycal were significantly higher than those of Biodentine and TheraCal. Because of the affinity of cells to porous surfaces, the pulp capping materials' microstructure may affect the pulp capping treatment's success. From this perspective, the use of Bioaggregate in direct pulp capping may increase the success of treatment.

The effect of whitening toothpastes on colour change and surface roughness of restorative materials

To examine the colour change and surface roughness of giomer, microhybrid composite and nanohybrid composite after brushing with whitening toothpastes. Disc-shaped samples of giomer, microhybrid composite and nanohybrid composite were divided into three subgroups(n=10), with the initial colour measured with a spectrophotometer and the surface roughness measured with a mechanical profilometer. The samples, which were immersed in coffee solution were brushed once a day with whitening toothpastes (Opalescence Cool Mint (OCM), Colgate Optic White Extra Power (COW) and Signal White Now Gold (SWN)) for 12 days. Colour change and surface roughness were measured again after the colouring-brushing cycle. All of the analyses were performed using appropriate statistical hypothesis tests. The highest increase in surface roughness was seen in the microhybrid composite group applied with SWN (p<0.05). The group with the least increase was the giomer group applied with SWN (p<0.05). While the least colour change was observed in the COW applied nanohybrid composite group (ΔE00=1,814), the most colour change occurred in the COW applied giomer group (ΔE00=5.943). After the use of whitening toothpastes, the roughness of giomer, microhybrid composite and nanohybrid composite surfaces was increased and a colour change above the clinically accepted value was observed.

El objetivo del presente estudio fue evaluar el cambio de color y la rugosidad de la superficie de giomer, resina compuesta microhíbrida y resina compuesta nanohíbrida posterior al cepillado con dentífricos blanqueadores. Las muestras en forma de disco de cada material se dividieron en tres subgrupos (n=10), con el color inicial medido con un espectrofotómetro y la rugosidad de la superficie medida con un perfilómetro mecánico. Las muestras, que se sumergieron en una solución de café, se cepillaron una vez al día con pastas dentales blanqueadoras (Opalescence Cool Mint (OCM), Colgate Optic White Extra Power (COW) y Signal White Now Gold (SWN)) durante 12 días. El cambio de color y la rugosidad de la superficie se midieron nuevamente después del ciclo de coloración-cepillado. El mayor aumento en la rugosidad de la superficie se observó en el grupo de la resina compuesta microhíbrida al que se le aplicó SWN (p<0,05). El grupo de menor incremento fue el grupo de giomer aplicado con SWN (p<0.05). Mientras que el menor cambio de color se observó en el grupo de resina compuesta nanohíbrida aplicado con COW (ΔE00=1,814), el mayor cambio de color ocurrió en el grupo de giomer con COW (ΔE00=5,943). Posterior al uso de pastas dentales blanqueadoras, la rugosidad del giomer, y de las resinas compuestas microhíbridas y nanohíbridas aumentó, siendo que se observó un cambio de color por encima del valor clínicamente aceptado.

Evaluation of the effects of whitening toothpaste containing nanohydroxyapatite on surface roughness and color change in restorative materials.

Background: The effects of whitening toothpastes containing nanohydroxyapatite on the surfaces of restorative materials are not well known. This study evaluated the changes in surface roughness and color of coffee-stained restorative materials after brushing with nanohydroxyapatite and other whitening toothpastes. Methods: Disc-shaped specimens were formed using microhybrid, nanohybrid, and supra-nano-filled composite (n = 30) and stained with a coffee solution. A brushing simulation was applied with toothpastes containing nanohydroxyapatite (Dentiste Plus White), perlite (Signal White System) and hydrogen peroxide (Colgate Optic White) for 7, 15, and 30 days. Color and surface roughness measurements were taken before and after brushing. Color change (∆E00) was calculated using the CIEDE2000 system. Results: Supra-nano-filled composite-Dentiste Plus White, supra-nano-filled composite-Colgate Optic White, and nanohybrid composite-Signal White System were the groups with the greatest color change observed on the 7th, 15th, and 30th days, respectively. The smallest color change was seen in the microhybrid composite-Signal White System, microhybrid composite-Dentiste Plus White, and nanohybrid composite-Dentiste Plus White groups on the 7th, 15th, and 30th days, respectively. No significant surface roughness changes were observed in the nanohybrid composite-Dentiste Plus White, supra-nano-filled composite-Colgate Optic White, supra-nano-filled composite-Dentiste Plus White, or supra-nano-filled composite-Signal White System groups. Conclusions: Whitening toothpaste containing nanohydroxyapatite provided a high degree of color change in the short term and did not create significant surface roughness in nanohybrid or supra-nano-filled composites.

Evaluation of plaque index, gingival index and oral health-related quality of life in obese patients / Evaluación del índice de placa, índice gingival y calidad de vida relacionada con la salud bucal en pacientes obesos

Obesity is a chronic disease that may be related to caries, periodontitis, xerostomia, and dental erosion, as well as increasing morbidity and mortality. The aim of this study was to evaluate the plaque index (Silness & Löe, 1964), the gingival index (Löe & Silness, 1963), and the oral health-related quality of life (OHRQoL) in obese patients. The study included 45 extremely obese, 45 obese, and 45 normal-weight individuals between the ages of 18 and 58. The plaque index and gingival index of the individuals were determined by clinical examination by probing. In addition, the Oral Health Impact Profile-14 (OHIP-14) questionnaire was used for the OHRQoL. The IBM SPSS Statistic 22.0 software program was used for the statistical evaluation of the study data. The plaque index and gingival index values were statistically higher in obese compared to normal weight individuals (p0.05). There was no statistically significant difference between the OHIP-14 total scores of the groups (p>0.05). Increased apparent plaque index and gingival index values in obese patients may adversely affect periodontal health.

La obesidad es una enfermedad crónica que puede estar relacionada con caries, periodontitis, xerostomía y erosión dental, además de aumentar la morbimortalidad. El objetivo de este estudio fue evaluar el índice de placa, el índice gingival y la calidad de vida relacionada con la salud bucal (CVSB) en pacientes obesos. El estudio incluyó a 45 individuos extremadamente obesos, 45 obesos y 45 de peso normal entre las edades de 18 y 58 años. El índice de placa y el índice gingival de los individuos se determinaron mediante examen clínico y sondaje periodontal. Además, se utilizó el cuestionario Oral Health Impact Profile-14 (OHIP-14) para la evaluación CVSB. Se utilizó el programa informático IBM SPSS Statistic 22.0 para la evaluación estadística. Los valores del índice de placa y del índice gingival fueron estadísticamente más altos en obesos en comparación con los individuos de peso normal (p0,05). No hubo diferencia estadísticamente significativa entre las puntuaciones totales de OHIP-14 de los grupos (p>0,05). El aumento del índice de placa aparente y los valores del índice gingival en pacientes obesos pueden afectar negativamente la salud periodontal.

A Novel Deep Learning-Based Approach for Segmentation of Different Type Caries Lesions on Panoramic Radiographs.

The study aims to evaluate the diagnostic performance of an artificial intelligence system based on deep learning for the segmentation of occlusal, proximal and cervical caries lesions on panoramic radiographs. The study included 504 anonymous panoramic radiographs obtained from the radiology archive of Inonu University Faculty of Dentistry's Department of Oral and Maxillofacial Radiology from January 2018 to January 2020. This study proposes Dental Caries Detection Network (DCDNet) architecture for dental caries segmentation. The main difference between DCDNet and other segmentation architecture is that the last part of DCDNet contains a Multi-Predicted Output (MPO) structure. In MPO, the final feature map split into three different paths for detecting occlusal, proximal and cervical caries. Extensive experimental analyses were executed to analyze the DCDNet network architecture performance. In these comparison results, while the proposed model achieved an average F1-score of 62.79%, the highest average F1-score of 15.69% was achieved with the state-of-the-art segmentation models. These results show that the proposed artificial intelligence-based model can be one of the indispensable auxiliary tools of dentists in the diagnosis and treatment planning of carious lesions by enabling their detection in different locations with high success.

Evaluation of a collagen-bioaggregate composite scaffold in the repair of sheep pulp tissue.

PURPOSE: This study aimed to compare the effects of the collagen-BioAggregate mixture (CBA-M) and collagen-BioAggregate composite (CBA-C) sponge as a scaffolding material on the reparative dentin formation. MATERIALS AND METHODS: CBA-C sponge (10:1 w/w) was obtained and characterized by Scanning Electron Microscopy (SEM) and Mercury Porosimetry. Cytotoxicity of the CBA-C sponge was tested by using the L929 mouse fibroblast cell line. Dental pulp stem cells (DPSCs) were isolated from the pulp tissue of sheep teeth and characterized by flow cytometry for the presence of mesenchymal stem cell marker, CD44. The osteogenic differentiation capability of isolated DPSCs was studied by Alizarin Red staining. The cells were then used to study for the compatibility of CBA-C sponge with cell proliferation and calcium phosphate deposition. The effect of CBA-C sponge and CBA-M on the induction of dentin regeneration was studied in the perforated teeth of sheep for the eight-week period. All the analyses were performed with appropriate statistical hypothesis tests. RESULTS: CBA-C sponge was found to be biocompatible for DPSCs. The DPSCs seeded on the CBA-C sponge were able to differentiate into the osteoblastic lineage and deposit calcium phosphate crystals in vitro. Reparative dentin formation was observed after the second week in the CBA-C sponge applied group. At the end of eight weeks, a complete reparative dentin structure was formed in the CBA-C sponge applied group, whereas necrotic tissue residues were observed in groups treated with the CBA-M. CONCLUSION: CBA-C sponge represents a better microenvironment for reparative dentin formation probably due to maintaining DPSCs and allowing their osteogenic differentiation and thus calcium phosphate deposition.

In vitro comparison of physical, chemical, and mechanical properties of graphene nanoplatelet added Angelus mineral trioxide aggregate to pure Angelus mineral trioxide aggregate and calcium hydroxide.

It is important to cover the pulp surface with a biocompatible material that is physically, mechanically, and chemically adequate. Graphene has the potential to form hard tissue, but at high doses, it shows toxic effects. It can be added to biocompatible materials at low doses to enhance their hard tissue forming potential. The aim of this study was to compare the physical, chemical, and mechanical properties of graphene nanoplatelet (GNP) added Angelus mineral trioxide aggregate (A-MTA) to pure A-MTA and calcium hydroxide. Homogeneous mixtures (created by adding +0.1 weight[wt]% and 0.3 wt% GNP to A-MTA), pure A-MTA, and Dycal were used. Three disc-shaped samples of each material were prepared using Teflon mold. Scanning electron microscope-energy dispersive X-ray (SEM-EDX), particle size, microhardness, and Fourier transform infrared spectroscopy (FTIR) analysis of the materials were performed in vitro. Data were analyzed using Kruskal-Wallis test followed by Conover test (p < .001). A-MTA and GNP added samples showed similar peaks in FTIR analysis. In the EDX analysis, the amount of carbon was observed with a higher increase at A-MTA + 0.3 wt% GNP than A-MTA + 0.1 wt% GNP. In the SEM image, hollow structure and particle size decreased as the amount of GNP increased; particle size was smaller at A-MTA + 0.3 wt% GNP than A-MTA + 0.1 wt% GNP (p < .001). A-MTA + 0.3 wt% GNP showed the highest microhardness while Dycal showed the lowest microhardness. The addition of GNP, a material with high potential for forming hard tissue, to the structure of capping materials can also positively contribute to the microhardness of the capping materials.

Comparative analysis of three different filling techniques and the effects of experimental internal resorptive cavities on apical microleakage.

OBJECTIVES: The aim of this study was to evaluate the sealing abilities of three different gutta-percha techniques in experimentally defective roots (EDR) and non-defective roots (NR). MATERIALS AND METHODS: Sixty canine teeth were divided into six groups of ten; Group 1, NR + cold lateral condensation (CLC); Group 2, EDR + LC; Group 3, NR + BeeFill; Group 4, EDR + BeeFill; Group 5, NR + Thermafil; and Group 6, EDR + Thermafil. Apical leakage was measured using a computerized fluid filtration meter with a laser system. RESULTS: Statistical analysis revealed that the CLC demonstrated more microleakage in the EDR than in the NR (P < 0.01). Thermafil demonstrated more microleakage in the NR than in the EDR (P < 0.01). No statistically significant differences were found between the BeeFill groups (P > 0.05). CONCLUSIONS: The results of this study indicate that internal resorptive cavities can affect the apical sealing properties of different root canal filling techniques, with Thermafil ensuring the lowest apical microleakage.