Color Alterations, Flexural Strength, and Microhardness of 3DPrinted Resins Treated in Different Coloring Agents.

Purpose This study evaluated the color alterations, flexural strength and microhardness properties of two different 3D-printed permanent crown resins. Materials and Methods Samples were produced from two different 3D Print permanent crown resins: Group 1 (Saremco Crowntec; Saremco, Switzerland), Group 2 (P-crown Version 2; Senertek, Turkey). Color changes (ΔE values), flexural strenght and vickers hardness number of the samples were calculated. Data were analyzed with Shapiro-Wilk normality test, Independent-t test, and Mann Whitney-U tests. Significance level was accepted as P<0.05. Results ΔE values for red wine were found to be significantly higher in Group 1 (6.43Å}2.26; P<0.001). The flexural strength values (MPa) of Group 1 were significantly higher than Group 2 in all three solutions (P<0.001). There was no significant difference between the VHN values of the samples kept in wine and coffee solutions (P= 0.271; 0.827). Conclusion 3D printing resins are affected at different levels by coloring solutions. Microhardness and flexural strength of 3D print samples kept in different coloring agents are different.In the use of 3D printing resins, product selection should be made by taking into account the individual factors such as the eating and drinking habits of the patients and the physical properties expected from the sample.

Effects of three disinfection solutions on residual monomers released from resin nanoceramic CAD/CAM blocks.

The aim of this study was to evaluate the effects of three disinfection solutions on the amount of monomers released from resin nanoceramic CAD/CAM blocks using high performance liquid chromatography (HPLC). Forty resin nanoceramic CAD/CAM (Cerasmart, GC, Japan) samples (12x14 × 2 mm) were divided into four groups; each group was disinfected using one of four solutions (Group 1: no disinfectant; Group 2: 70 % ethanol; Group 3: 2 % glutaraldehyde; and Group 4: 1 % sodium hypochlorite) for 5 min. Analysis of residual monomers (UDMA and Bis-EMA) amounts was performed using an HPLC instrument (Dionex Ultimate 3000, Thermo Fisher Scientific). After 30 days, the amounts of monomers found were as follows: 14.54 ppm for Group 1; 9.28 ppm for Group 2; 10.60 ppm for Group 3; and 2.76 ppm for Group 4 (the smallest monomer amount) (p < 0.001). Disinfection of indirect restorations prior to cementation can reduce the amount of residual monomers remaining from resin nanoceramic CAD/CAM blocks.

Effect of repeated preheating on monomer elution from a bulk-fill composite resin.

Background: Due to incomplete polymerization of composite resin restorations, residual monomers adversely affect their mechanical properties and biocompatibility. Preheating of composite resins is advised to increase the degree of conversion and reduce monomer elution. This study aimed to analyze the effect of preheating and repeated preheating on the amount of monomer released from a bulk-fill composite resin. Methods: Forty samples were prepared using Filtek One Bulk Fill Restorative composite resin. Samples in one group were fabricated at room temperature, whereas the composite resins in the other groups were cured after 1, 10, or 20 repeated preheating cycles (55 °C), 10 in each group. Eluted urethane dimethacrylate (UDMA) and bisphenol-A-glycidylmethacrylate (BisGMA) monomers were measured with high-performance liquid chromatography (HPLC) 24 hours and 30 days after immersion. The data were evaluated using one-way ANOVA and post hoc Tukey tests. Paired-sample t tests were used to test the differences between time intervals. Results: At both time intervals, the greatest amounts of released BisGMA, UDMA, and total monomers were obtained from the control group, whereas 10 preheating cycles resulted in the least monomer elution. The decrease in monomer elution was not statistically significant after 10 preheating cycles compared with that after one preheating cycle (P>0.05). The group with 20 preheating cycles showed a greater amount of monomer elution compared to that with 1 and 10 cycles, which was statistically significant (P < 0.05). The amount of released monomers on day 30 was significantly higher than on day 1 (P<0.01). Conclusion: Preheating of the bulk-fill composite resin was shown to be effective in reducing monomer elution. However, monomer elution was adversely affected after repeated preheating cycles of 20.

Deep-learning approach for caries detection and segmentation on dental bitewing radiographs.

OBJECTIVES: The aim of this study is to recommend an automatic caries detection and segmentation model based on the Convolutional Neural Network (CNN) algorithms in dental bitewing radiographs using VGG-16 and U-Net architecture and evaluate the clinical performance of the model comparing to human observer. METHODS: A total of 621 anonymized bitewing radiographs were used to progress the Artificial Intelligence (AI) system (CranioCatch, Eskisehir, Turkey) for the detection and segmentation of caries lesions. The radiographs were obtained from the Radiology Archive of the Department of Oral and Maxillofacial Radiology of the Faculty of Dentistry of Ordu University. VGG-16 and U-Net implemented with PyTorch models were used for the detection and segmentation of caries lesions, respectively. RESULTS: The sensitivity, precision, and F-measure rates for caries detection and caries segmentation were 0.84, 0.81; 0.84, 0.86; and 0.84, 0.84, respectively. Comparing to 5 different experienced observers and AI models on external radiographic dataset, AI models showed superiority to assistant specialists. CONCLUSION: CNN-based AI algorithms can have the potential to detect and segmentation of dental caries accurately and effectively in bitewing radiographs. AI algorithms based on the deep-learning method have the potential to assist clinicians in routine clinical practice for quickly and reliably detecting the tooth caries. The use of these algorithms in clinical practice can provide to important benefit to physicians as a clinical decision support system in dentistry.

An artificial intelligence proposal to automatic teeth detection and numbering in dental bite-wing radiographs.

OBJECTIVES: Radiological examination has an important place in dental practice, and it is frequently used in intraoral imaging. The correct numbering of teeth on radiographs is a routine practice that takes time for the dentist. This study aimed to propose an automatic detection system for the numbering of teeth in bitewing images using a faster Region-based Convolutional Neural Networks (R-CNN) method. METHODS: The study included 1125 bite-wing radiographs of patients who attended the Faculty of Dentistry of Ordu University from 2018 to 2019. A faster R-CNN an advanced object identification method was used to identify the teeth. The confusion matrix was used as a metric and to evaluate the success of the model. RESULTS: The deep CNN system (CranioCatch, Eskisehir, Turkey) was used to detect and number teeth in bitewing radiographs. Of 715 teeth in 109 bite-wing images, 697 were correctly numbered in the test data set. The F1 score, precision and sensitivity were 0.9515, 0.9293 and 0.9748, respectively. CONCLUSIONS: A CNN approach for the analysis of bitewing images shows promise for detecting and numbering teeth. This method can save dentists time by automatically preparing dental charts.

In Vitro Effect of Temperature on Dentin Bond Strength of Universal Adhesive Systems / Efecto In Vitro de la temperatura sobre la resistencia de unión de los sistemas adhesivos universales a la dentina

ABSTRACT The aim of this study was to evaluate the shear bond strength (SBS) of two universal adhesives (Universal Single Bond and All Bond Universal) and a two- step self-etch adhesive system (Clearfil SE Bond) to dentine at various temperatures. Materials and Methods: One hundred and twenty dentin specimens were divided randomly to 12 groups, according to adhesive systems (Universal Single Bond and All Bond Universal, Clearfil SE Bond) and temperature ( 4ºC, 20 ºC, 36ºC, 55ºC) used. Dentin specimens were prepared (n :10, adhesives were applied, and composite cylinders were polymerized. Statistical analysis of the SBS data was performed using Two-way analysis of variance (ANOVA) and Tukey's Honestly Significant Differences post-hoc test. Results: The Clearfil SE Bond was shown to have higher SBS than the universal adhesives at all temperatures; however, there was no statistically significant difference (P>0.05). In both groups, the lowest SBS values were observed in the samples at 4°C while the highest SBS values were observed in the samples at 55°C. In this case, there was a statistically significant difference (P<0.05). Conclusions: The results suggest that the effectiveness of an adhesive may increase if it is preheated at 36°C or above before use instead of being used immediately after removal from the refrigerator or at room temperature.

RESUMEN El objetivo de este estudio fue evaluar la resistencia al cizallamiento (SBS) de dos adhesivos universales (Universal Single Bond y All Bond Universal) y un sistema de adhesivo de autograbado de dos pasos (Clearfil SE Bond) a la dentina en diferentes temperaturas. Materiales y métodos: Ciento veinte muestras de dentina se dividieron aleatoriamente en 12 grupos, de acuerdo con los sistemas adhesivos (Universal Single Bond y All Bond Universal, Clearfil SE Bond) y la temperatura (4ºC, 20ºC, 36ºC, 55ºC) utilizada. Se prepararon muestras de dentina (n: 10), se aplicaron los sistemas adhesivos y se polimerizaron los cilindros compuestos. El análisis estadístico de los datos de SBS se realizó utilizando el análisis de varianza de dos vías (ANOVA) y la prueba post-hoc de Tukey's. Resultados: El Clearfil SE Bond mostró tener un SBS más alto que los adhesivos universales en todas las temperaturas evaluadas; sin embargo, no hubo una diferencia estadísticamente significativa (P> 0.05). En todos los grupos, los valores más bajos de SBS se observaron en las muestras a 4°C, mientras que los valores de SBS más altos fueron obtenidos en las muestras a 55°C (P <0.05). Conclusiones: Los resultados sugieren que la efectividad de un adhesivo puede aumentar si se precalienta a 36°C o superior, antes de usarlo inmediatamente después de sacarlo del refrigerador o a temperatura ambiente.

Association Between Body Mass Index and Dental Caries in a Turkish Subpopulation of Adults: A Cross-Sectional Study.

PURPOSE: To evaluate the relationship between decayed, missing and filled teeth (DMFT index) and body mass index (BMI) in a Turkish population of adults aged 20-30 years who did not have any chronic diseases. MATERIALS AND METHODS: This study was conducted on a total of 394 patients. DMFT index was used to define the number of teeth with decays, teeth with fillings, and missing teeth. The body weight and height of the study participants were measured with a digital scale and height rod. BMI was calculated by dividing the body weight by the square root of the height. One-way analysis of variance (ANOVA) and Bonferroni tests were used to compare three or more groups and to compare two groups, respectively. The statistical significance level was evaluated at p < 0.05. RESULTS: Differences in DMFT index among BMI groups was found to be statistically significant (p = 0.001; p < 0.01). DMFT index was significantly higher in the obese group than in the normal-weight group (p = 0.001) and overweight group (p = 0.001). No statistically significant differences were found between DMFT indices of study participants of normal weight and those who were overweight (p > 0.05). CONCLUSION: Positive correlation was observed between obesity and DMFT index. Coadministration of obesity prevention programmes and preventive oral health programmes can improve public health to a better point.

Influence of Bulk-Fill Composites, Polimerization Modes, and Remaining Dentin Thickness on Intrapulpal Temperature Rise.

OBJECTIVES: The aim of this study was to compare the effects of different bulk-fill resin composites, polimerization modes, and the thickness of remaining dentin on the increase of intrapulpal temperature. METHODS: Human-extracted upper premolar teeth (n = 10) were used to design a single-tooth model with remaining dentin thicknesses of 1 mm and 0.5 mm. Estelite Bulk-fill Flow (Tokuyama, Japan), Surefil SDR™ Flow (Dentsply Caulk, Brazil), Filtek Bulk-Fill Posterior (3M, USA), and SonicFill™ 2 Bulk-fill (Kerr, USA) composites were applied according to the manufacturer's instructions. The standard and high modes of a light emitted diode (LED) light curing unit (LCU) (VALO™ Utradent, USA), were used for polymerization. In order to mimic the in vivo conditions of pulpal circulation, digital flowmetry (SK-600II, SK Medical, China) was used. Intrapulpal temperature rise was measured using K type thermocoupling (CEM DT 610B, Robosem Engineering, China). Data were analyzed using three-way variance analysis (ANOVA) and the independent t-test. RESULTS: No significant statistical differences in intrapulpal temperature rise between low viscosity bulk-fill composites (SDR and Estelite) were found. The lowest intrapulpal temperature rise was found in groups which used the Filtek Bulk-fill composite. Decreases in the remaining dentin thickness increased the intrapulpal temperature rise. SIGNIFICANCE: This study demonstrated that remaining dentin thickness, filler ratio of bulk-fill composites, and power and application time of the LED-LCU may affect intrapulpal temperature rise.

Effects of adhesive systems at different temperatures on the shear bond strength of orthodontic brackets.

Background. The temperature might affect the physical and mechanical properties of adhesive materials by reducing the polymerization rate. The present study aimed to evaluate the effect of temperature on the shear bond strength of metallic orthodontic brackets using various adhesive resin systems. Methods. Extracted human premolar teeth were randomly assigned to 8 groups (n=10) for bonding with the two available orthodontics adhesive systems (Transbond XT and NeoBond) at different temperatures: refrigeration temperature (4°C), room temperature (20°C), human body temperature (36°C) and high temperature (55°C). The shear bond strength (SBS) test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The adhesive remnant index (ARI) was assigned to the fractured orthodontic brackets. Data were analyzed with one-way ANOVA, post hoc Tukey tests and independent t-test. Results. Transbond XT exhibited higher SBS values compared to Neobond at all the tested temperatures; however, a statistically significant difference was not observed (P>0.05). The SBS results were minimum at 4°C and maximum at 36°C in both the adhesive groups (P<0.05). Conclusion. Pre-heating orthodontic adhesives up to the body temperature prior to bonding the brackets in orthodontic treatment increased the bond strength of orthodontic brackets.

In Vitro Comparison of ICDAS And DIAGNOdent Pen in The Diagnosis and Treatment Decisions of Non-Cavitated Occlusal Caries / Comparación In Vitro de ICDAS y DIAGNOdent Pen en el diagnóstico y decisiones de tratamiento de la caries oclusal no cavitada

Abstract The aim of this study was to compare the efficacy of the ICDAS and the DIAGNOdent Pen in the diagnosis of occlusal caries lesions without cavitation, and for basing treatment decisions on the results obtained. Eighty permanent molar teeth that were healthy and non-cavitated or that had an initial occlusal lesion were evaluated. All teeth were investigated using DIAGNOdent Pen and ICDAS by four examiners. Histological evaluation of teeth was performed using stereomicroscopy by a histologist and different experienced dentist. For evaluation of the data, weighted kappa values (kw), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and likelihood ratio (LR+) values of the tests were calculated. The diagnostic results obtained using the DIAGNOdent Pen were found to correlate better with the results obtained from histological sections than those obtained using ICDAS. When the treatment decisions of the observers depending on the results of ICDAS, and ICDAS and DIAGNOdent Pen combination were compared with the decisions made based on histological examinations, the decisions based on ICDAS and DIAGNOdent Pen combined (kw: 0.522) were more accurate than the ones based on ICDAS (kw: 0.415) alone. In conclution, professional experience is an effective factor in diagnosing occlusal caries lesions without cavitation with ICDAS and in making treatment decisions for them. DIAGNOdent Pen is sufficient in diagnosing occlusal caries lesions without cavitation.

Resumen El objetivo de este estudio fue comparar la eficacia de ICDAS y de DIAGNOdent Pen en el diagnóstico de lesiones de caries oclusales no cavitadas. Ochenta molares permanentes sanos y no cavitados fueron utilizados. Todos los dientes fueron investigados usando DIAGNOdent Pen e ICDAS por cuatro examinadores. La evaluación histológica de los dientes se realizó mediante estereomicroscopía por un histólogo y por un dentista con previa experiencia. Los resultados diagnósticos obtenidos con el DIAGNOdent Pen se correlacionan mejor con los resultados obtenidos a partir de las secciones histológicas cuando comparados a los obtenidos utilizando ICDAS. Las decisiones basadas en el uso combinado de ICDAS y DIAGNOdent Pen (kw: 0.522) fueron más precisas que los basados en ICDAS (kw: 0.415). En conclusión, la experiencia profesional es un factor eficaz en diagnóstico de lesiones de caries oclusal sin cavitación con ICDAS y en la toma de decisiones de tratamiento. DIAGNOdent Pen es una herramienta confiable para diagnosticar lesiones de caries oclusales sin cavitación.

In vivo comparison of the efficacy of DIAGNOdent by visual inspection and radiographic diagnostic techniques in the diagnosis of occlusal caries.

OBJECTIVE: The purpose of this study was to compare in vivo the efficacy of DIAGNOdent measurements in the diagnosis of occlusal caries with conventional diagnostic methods (visual inspection and radiographic methods). METHODOLOGY: A total of 187 molar teeth in 161 individuals (87 female, 74 male) between the ages of 18 and 25, who were admitted to the Ondokuz Mayis University Faculty of Dentistry, Department of Restorative Dentistry, were included in this study. The study was evaluated by Ondokuz Mayis University Faculty of Medicine Ethical Committee and approved as ethically applicable. In the diagnostic phase of the study, all subjects' teeth were evaluated by two observers sequentially by visual inspection, radiography, and using DIAGNOdent. Carious lesions on the occlusal surfaces of molar teeth, which were evaluated by visual inspection, radiography and DIAGNOdent, were removed by using rotational cutting devices. Resulting cavities following caries removal were visually evaluated, and the level of caries was determined. RESULTS: Statistically significant differences were found when the visual inspection results, radiographic evaluation results, and DIAGNOdent evaluation results of two observers were compared for cavity depths. CONCLUSION: Although DIAGNOdent is an important diagnostic device, particularly for diagnosing hidden carious lesions in the dentine layer, it should be used along with visual examination in clinical practice, as DIAGNOdent is not superior to visual examination in detecting early stages of carious lesions.