Comparative Analysis of Root Canal Dentin Removal Capacity of Two NiTi Endodontic Reciprocating Systems for the Root Canal Treatment of Primary Molar Teeth. An In Vitro Study

The objective of the present study was to evaluate and compare the dentin removal capacity of Endogal Kids and Reciproc Blue NiTi alloy endodontic reciprocating systems for root canal treatments in primary second molar teeth via a micro-computed tomography (micro-CT) scan. Materials and Methods: Sixty root canal systems in fifteen primary second molar teeth were chosen and classified into one of the following study groups: A: EK3 Endogal Kids (n = 30) (EDG) and B. R25 Reciproc Blue (n = 30) (RB). Preoperative and postoperative micro-CT scans were uploaded into image processing software to analyze the changes in the volume of root canal dentin using a mathematical algorithm that enabled progressive differentiation between neighboring pixels after defining and segmenting the root canal systems in both micro-CT scans. Volumetric variations in the root canal system and the root canal third were calculated using a t-test for independent samples or a nonparametric Mann–Whitney–Wilcoxon test. Results: Statistically significant differences (p = 0.0066) in dentin removal capacity were found between the EDG (2.89 ± 1.26 mm3) and RB (1.22 ± 0.58 mm3) study groups for the coronal root canal third; however, no statistically significant differences were found for the middle (p = 0.4864) and apical (p = 0.6276) root canal thirds. Conclusions: Endogal and Reciproc Blue NiTi endodontic reciprocating systems showed similar capacity for the removal of root canal dentin, except for the coronal root canal third, in which the Reciproc Blue NiTi endodontic reciprocating system preserved more root canal dentin tissue.

Development of an artificial intelligence-based algorithm to classify images acquired with an intraoral scanner of individual molar teeth into three categories

Background Forensic dentistry identifies deceased individuals by comparing postmortem dental charts, oral-cavity pictures and dental X-ray images with antemortem records. However, conventional forensic dentistry methods are time-consuming and thus unable to rapidly identify large numbers of victims following a large-scale disaster. Objective Our goal is to automate the dental filing process by using intraoral scanner images. In this study, we generated and evaluated an artificial intelligence-based algorithm that classified images of individual molar teeth into three categories: (1) full metallic crown (FMC); (2) partial metallic restoration (In); or (3) sound tooth, carious tooth or non-metallic restoration (CNMR). Methods A pre-trained model was created using oral-cavity pictures from patients. Then, the algorithm was generated through transfer learning and training with images acquired from cadavers by intraoral scanning. Cross-validation was performed to reduce bias. The ability of the model to classify molar teeth into the three categories (FMC, In or CNMR) was evaluated using four criteria: precision, recall, F-measure and overall accuracy. Results The average value (variance) was 0.952 (0.000140) for recall, 0.957 (0.0000614) for precision, 0.952 (0.000145) for F-measure, and 0.952 (0.000142) for overall accuracy when the algorithm was used to classify images of molar teeth acquired from cadavers by intraoral scanning. Conclusion We have created an artificial intelligence-based algorithm that analyzes images acquired with an intraoral scanner and classifies molar teeth into one of three types (FMC, In or CNMR) based on the presence/absence of metallic restorations. Furthermore, the accuracy of the algorithm reached about 95%. This algorithm was constructed as a first step toward the development of an automated system that generates dental charts from images acquired by an intraoral scanner. The availability of such a system would greatly increase the efficiency of personal identification in the event of a major disaster.

Comparison of the Effectiveness of Chemo-mechanical and Traditional Caries Removal Methods in Primary Teeth Using Micro-Computed Tomography

Purpose: The purpose of this study was to evaluate dentin mineral density before and after caries removal with the traditional caries removal technique and chemo-mechanical method, with or without the use of caries detection dye. Our null hypothesis was that the chemo-mechanical method with minimally invasive treatment would achieve an effect similar to that of conservative pediatric dentistry treatment. Materials & Methods: Forty-eight medium-sized, interfacial decayed primary molar teeth without pulpal perforation were selected. Two groups were formed by Papacarie Duo and conventional method; then four sub-groups were formed by two caries detection dye applied or not applied groups, twelve teeth were randomly divided into each group. The teeth were then treated with chemo mechanical and traditional caries removal approach. Teeth were scanned with the same voxel sizes using micro-computed tomography images to figure out the difference dentin mineral density and to calculate the removed dentinal volume after chemo-mechanical or traditional method application. Results: The results showed increase of cavity volume in the chemo-mechanical and traditional method groups. No significant difference was found for cavity volume and dentinal carious volume in both groups (p>0.05). The mineral density values of demineralized dentin were between 0.52-0.66 g/cm3 before caries removal, and 1.39-1.59 g/cm3 after removing caries. These values were found to be within the range of healthy dentin mineral density values again without any significant difference between groups (p>0.05). Conclusion: In conclusion, chemo-mechanical methods can be used effectively for removing the caries in the primary molar teeth similar to conservative treatments.

Recovery of Candida spp. from a denture rat model

Denture stomatitis is a common infection in denture wearers. This study evaluated the recovery of Candida spp. from the palate of Wistar rats after using an acrylic device with single and mixed-species of Candida spp. After approval of the Ethics Committee, 84 male and female Wistar rats were used. Custom-made acrylic devices were fabricated for each animal and sterilized by microwave irradiation. Single and mixed species biofilms of C. albicans (Ca), C. glabrata (Cg), and C. tropicalis (Ct) were grown on the devices for 48 h at 37°C. Rats were anesthetized and the devices were cemented on the molar teeth (n=5 for each sex and Candida spp.). Rats received a carbohydrate-rich diet. Single and mixed species were inoculated in the oral cavity thrice after three-day intervals. Controls received only dentures without Candida spp. After 4 weeks, the devices were removed, the palates were swabbed, and diluted samples were plated on Agar Sabouraud Dextrose and CHROMAgar Candida for colony counting and presumptive identification, respectively, after 48 h. Data were analyzed by 3way ANOVA (α=5%). There was a significant interaction (p=0.003) between sex and species. For females, all groups recovered significant values (p≤0.027) compared with controls. For males, groups with Ct as single and dual-species showed the lowest values without difference (p≥0.183) with the control. The groups with triple-species showed the highest values but without difference (p≥0.071) with the groups with single and dual-species, except males with Ct. Ct alone showed reduced recovery from palate of male rats.

Outcomes and Stability of Anterior Open Bite Treatment with Skeletal Anchorage in Non-Growing Patients and Adults Compared to the Results of Orthognathic Surgery Procedures: A Systematic Review

The objective of this review is to evaluate, on the basis of the available literature, if anterior open bite (AOB) can be successfully treated with the intrusion of molar teeth using skeletal anchorage in non-growing patients and adults and if this treatment modality provides comparable results to those obtained by orthognathic surgery procedures. Methods: A systematic review of published data in major databases from 2000 to 2021 was performed. Results: In total, 92 articles were included in title and abstract screening, and only 16 articles (11 concerning AOB correction by molar intrusion with skeletal anchorage, and five considering AOB treatment by orthognathic surgical intervention) qualified for thorough data extraction and analysis. Conclusions: On the basis of this review, it seems to be possible to obtain successful results for AOB treatment in non-growing patients and adults by means of the intrusion of molar teeth with skeletal anchorage. However, due to the different methods of assessing treatment outcomes used by different authors, it is not possible to state conclusively whether the treatment of AOB by means of molar intrusion with skeletal anchorage provides long-term results that are comparable to orthognathic surgery procedures.

Effect of Different Cavity Disinfectants on Microleakage

BACKGROUND Cavity disinfectants are frequently used for the elimination of bacteria that remain in the cavity, which are shown as the cause of secondary caries. However, its effect on microleakage from the tooth-restoration interface is still under investigation. The purpose of this study was to compare and evaluate the effects of the use of three different cavity disinfectants on microleakage in Class V composite restorations. METHODS For this study, 28 permanent third molar teeth without caries and restoration were used. Class V cavities of 4 mm x 3 mm x 3 mm were prepared on the buccal surfaces of each tooth. The teeth were randomly divided into 4 groups, with 7 teeth in each group. No cavity disinfectant was applied to the teeth in group 1. Tubulicid Red Label (Dental Therapeutics AB, Sweden) cavity disinfectant was applied to the 2nd group teeth, Cavity Cleanser (BISCO Inc., USA) cavity disinfectant to the 3rd group teeth, and Oxygenated Water (Dermosept, Turkey) cavity disinfectant to the 4th group teeth. Composite resin with universal adhesive and nanohybrid filler was applied to all samples in the groups in accordance with the recommendations of the manufacturers, and finishing and polishing processes were performed. Then, the thermal cycle (NOVA, Konya, Turkey) procedure was applied. After the restorations were covered with nail polish, they were kept in a 5 % basic fuchsin solution. The teeth were cut vertically in the buccolingual direction and examined with a stereomicroscope at x 40 magnification. The results were statistically evaluated with Kruskal-Wallis and Mann-Whitney U tests. RESULTS When the microleakage scores were compared between the control group and the groups treated with Tubulicid Red Label (p:0.204), Cavity Cleanser (p:0.204) and Oxygenated Water (P: 0.788), it was determined that there was no statistically significant difference (P > 0.05). CONCLUSİONS It was determined that different cavity disinfectants applied in Class V cavities did not have a negative effect on microleakage and the closest results to the control group were seen in the group where cavity cleanser disinfectant containing 2 % chlorhexidine digluconate was applied. KEY WORDS Cavity Disinfectants, Class V Cavity, Microleakage.