Timing for extraction of permanent first molars in school aged children: a pilot study.

Extraction of permanent first molars (P1Ms) could create gaps, tipping and/or rotating of neighboring teeth, which depend on the extraction timing. This study evaluated the outcomes of P1Ms extraction in children who were classified based on their permanent second molar's (P2Ms) dental calcification at the time of extraction. In this retrospective study, the evaluations were made for 406 panoramic radiographs (PRs) of children aged 7-14 years who had single P1M extracted. Twenty-nine children having pre- and post-treatment PRs were selected based on the inclusion criteria. First, 2 groups were formed based on the extraction time by using the pre-treatment PRs; Early extraction group (EE) (n = 15) including Nolla Grades 5-6-7, and late extraction group (LE) (n = 14) including Nolla Grades 8-9-10 for P2Ms. Then, the inclination degrees of neighbouring teeth on extraction side and contralateral quadrant (non-extraction) side were measured by using the post-extraction PRs. Mann-Whitney U test was employed, and the statistical significance was set at p < 0.05. The mesial tipping tendency of P2M was significant towards the extraction side both at EE or LE calcification grades of P2Ms (p > 0.05). The mesial inclination degrees of maxillary P2Ms showed no statistically significant difference between the two sides of LE group. The ideal extraction time should be determined according to the dental age to plan an appropriate occlusal maintenance.

Simulation of three intraoral radiographic techniques in pediatric dental patients: subjective comfort assessment using the VAS and Wong-Baker FACES Pain Raiting Scale.

BACKGROUND: Perception of pain associated with intraoral radiography in pediatric patients was evaluated through statistical comparisons of data obtained using the Wong-Baker FACES Pain Raiting Scale (WBFPRS) and visual analog scale (VAS) scoring. METHODS: A total of 75 pediatric patients aged 6-12 years were included in this study. Simulations of each of three radiological methods (analog films, CCD sensor and phosphorus plates) were performed on 25 pediatric patients. Following the simulations, the meaning of each facial expression on the WBFPRS and the numbers on the VAS were explained to each child. For the comparison between groups, the homogeneity of the variances was tested with Levene's test; because the variances were not homogeneous, Welch's test was used. Tamhane's T2 test was used because the homogeneity assumption was not provided to determine the source of the difference between the groups. RESULTS: When the conventional method was compared to the PSPL (photostimulable phosphor luminescence) method, no significant differences were noted in either the WBFPRS or VAS results (p >0.05). The results obtained from both of the scales were significantly different between the conventional method and the CCD sensor method (p < 0.05). When the PSPL and CCD sensors were compared, a significant difference was observed for the WBFPRS (p < 0.05). It was found the highest level of pain scores when used the CCD sensor method than the analog film and PSPL methods (p < 0.05). CONCLUSIONS: It is expected that digital radiographic techniques will be improved in the future and that their disadvantages will be eliminated, resulting in imaging devices that are more comfortable for pediatric patients.

Remineralization potential of P11-4 and fluoride on secondary carious primary enamel: A quantitative evaluation using microcomputed tomography.

The aim of this study was to assess the ability of self-assembling peptide (P11-4) diffusion, assembly, and remineralization to effect artificial secondary caries-like lesions in human primary teeth in vitro. Enamel-dentin blocks obtained from extracted human primary molars were embedded into epoxy resin blocks. Cavities (approximately 1 × 1 × 2 mm) were prepared on the surface using a high-speed diamond bur under constant water cooling and filled with composite restorative material (Filtek Z250; 3 M ESPE). The samples were immersed in demineralizing solution (20 ml) for 96 h to produce secondary caries lesions and divided into two groups according to the testing materials: fluoride varnish (Duraphat; Colgate, UK) and P11-4 (Curodont Repair; Credentis, Switzerland). Except for the control areas, all samples were remineralized for 3-5 min using the remineralizing agents, and then all the sections were placed in a pH-cycling system for 5 days at 35°C. The pH cycling procedure was followed by micro-CT analysis for the qualitative evaluation of surface changes. The Mann-Whitney U test was used to compare two independent groups. In the comparison of more than two dependent groups, Bonferroni smoothed pairwise analyses were used to determine the source of the Kruskal-Wallis H test difference. The results of the study revealed that the remineralization depths of the peptide group were higher than those of the fluoride group (p < .01). There was a statistically significant difference in remineralization effects between the fluoride and peptide groups. P11-4 can be considered as an effective remineralizing agent for secondary caries lesions.

Dental enumeration and multiple treatment detection on panoramic X-rays using deep learning.

In this paper, a new powerful deep learning framework, named as DENTECT, is developed in order to instantly detect five different dental treatment approaches and simultaneously number the dentition based on the FDI notation on panoramic X-ray images. This makes DENTECT the first system that focuses on identification of multiple dental treatments; namely periapical lesion therapy, fillings, root canal treatment (RCT), surgical extraction, and conventional extraction all of which are accurately located within their corresponding borders and tooth numbers. Although DENTECT is trained on only 1005 images, the annotations supplied by experts provide satisfactory results for both treatment and enumeration detection. This framework carries out enumeration with an average precision (AP) score of 89.4% and performs treatment identification with a 59.0% AP score. Clinically, DENTECT is a practical and adoptable tool that accelerates the process of treatment planning with a level of accuracy which could compete with that of dental clinicians.

Coronal microleakage of temporary restorations in previously restored teeth with amalgam and composite.

AIM: This study evaluated microleakage at the interface between various temporary restorative materials and existing amalgam or composite restorations, and dental tissues in previously restored teeth after partial removal of the restoration. MATERIALS AND METHODS: The distal half of amal gam (Ag) and composite restorations (Co) in 45 teeth were removed, then filled with temporary restorative materials (IRM, Coltosol and CLIP). After thermal cycling, microleakage was measured microscopically as the penetration of basic fuchsine according to a four-unit-scale: The data were evaluated with Friedman and Kruskal-Wallis tests using Bonferroni correction (p < 0.05). RESULTS: In almost all groups except the Co-IRM and Ag-CLIP interface, lower microleakage values were observed in temporary restoration-permanent restoration interfaces compared to temporary restoration-tooth interfaces. For the Ag and Co groups except for the Ag-IRM-b interfaces, the highest microleakage values were observed with IRM for b and c interfaces followed by Coltosol and CLIP. Interestingly, although CLIP was a temporary restoration, CLIP-tooth interface (Ag-CLIP-c) values were lower than amalgam-tooth interface (Ag-CLIP-a) values. CONCLUSIONS: CLIP provided a better seal against microleakage at amalgam and especially composite interfaces. This material also provided a better seal against microleakage at the tooth tissue interface. The use of a resin based temporary restorative material over partially removed resin composite restorations could be beneficial in achieving better resistance to marginal leakage. Within the limitations of this study, maintaining partially removed permanent restorations does not seem to cause a problem with achieving marginal seal.