Background and Objectives: Periodontium is an important tooth-supporting tissue composed of both hard (alveolar bone and cementum) and soft (gingival and periodontal ligament) sections. Due to the multi-tissue architecture of periodontium, reconstruction of each part can be influenced by others. This review focuses on the bone section of the periodontium and presents the materials used in tissue engineering scaffolds for its reconstruction. Materials and Methods: The following databases (2015 to 2021) were electronically searched: ProQuest, EMBASE, SciFinder, MRS Online Proceedings Library, Medline, and Compendex. The search was limited to English-language publications and in vivo studies. Results: Eighty-three articles were found in primary searching. After applying the inclusion criteria, seventeen articles were incorporated into this study. Conclusions: In complex periodontal defects, various types of scaffolds, including multilayered ones, have been used for the functional reconstruction of different parts of periodontium. While there are some multilayered scaffolds designed to regenerate alveolar bone/periodontal ligament/cementum tissues of periodontium in a hierarchically organized construct, no scaffold could so far consider all four tissues involved in a complete periodontal defect. The progress and material considerations in the regeneration of the bony part of periodontium are presented in this work to help investigators develop tissue engineering scaffolds suitable for complete periodontal regeneration.

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Background and Objectives: Some of the disadvantages of the heat-cured acrylic resins include high porosity, high water absorption, volume changes, and a lot of residual monomer. The development of polymer chemistry produced different kinds of materials such as polyamide, Acetal resins, and etc. Recently, polyamide materials are widely used in the manufacture of denture base. Denture bases made from this material are more flexible than conventional PMMA. There is a direct relationship between surface roughness (as a result of polishing) and the retention of microbial plaque. This study compared the surface roughness of 2 polyamide materials with a heat-cure acrylic resin.Methods: A total of 60 wax samples (30 × 15 × 4 mm) were made. For preparation of PMMA specimens, 20 of the samples were heated in the 165°F water bath for 9 hours. Other 40 wax samples were used for the preparation of polyamide samples (TCS and VAL), according to the factory instructions. Polyamide samples were heated for 11 minutes at 274°C-293°C and then, injection was done for them. After finishing and polishing, the thickness of the samples decreased to 3 mm. Roughness was measured by a stylus profilometer (the length of the cutoff = 0.8 mm and speed of pen movement 0.5mm/s randomly in 3 regions of each sample. The t-test was used for a statistical analysis. Results:There is a significant difference between surface roughness of heat-cure acrylic resin with polyamide materials (P < 0.05), however there is no significant difference between surface roughness of 2 types of polyamide materials (P > 0.05). The surface roughness of all specimens was higher than the threshold level (0.2 µ).Conclusions: Due to the high surface roughness of polyamide materials, the use of polyamide materials cannot be recommended for the construction of permanent appliance. Surface roughness of heat-cure acrylic resin of Meliodent (PMMA) was higher than the accepted standard.

Background:The patient-centered approach improves the quality of health care. Promoting this approach will increase the patients' satisfaction and improve interpersonal skills among health care providers. Objectives:The aim of the current study was to compare the viewpoints of interns toward the patient-centered approach in the beginning and the end of the internship at the Kerman University of Medical Sciences (KUMS). Methods: This longitudinal study was carried out at KUMS between March 2017 and July 2018. All medical students who had passed the internship entrance exam were selected through a census. The Persian version of the patient-practitioner orientation scale (PPOS) was completed at the start and the end of the internship. This instrument has 18 items in two 9-item subscales: sharing and caring. The minimum and maximum scores were 1 to 6, respectively. The higher the score, the more the patient-centered orientation. The data were analyzed by SPSS using independent and paired t-tests, ANOVA, and multiple linear regression. Results:The mean scores of PPOS were 3.92 ± 0.42 and 3.86 ± 0.37 at the beginning and the end of the internship, respectively. This difference was not statistically significant. The mean score of the caring subscale significantly increased during internship but no significant change was found in the mean score of the sharing subscale. Conclusions:The results of our study showed that the patient-centered attitude toward patient caring improved during the internship in the majority of interns but no significant improvement was found in terms of patient sharing. Significant progress can be made in the quality of physician-patient communication and patient satisfaction if necessary training programs are run on patient-centeredness.

Background: New cone beam computed tomography (CBCT) devices have the ability to take images with different fields of views (FOVs) and resolutions. The larger the FOV and the higher resolution of the image, the higher the patient's dose would be. Objectives: This research aims to analyze the diagnostic accuracy of FOV's different dimensions and the various resolutions in the diagnosis of mandibular condyle erosions. Materials and Methods: CBCT images using NewTom VGi (Verona, Italy) system in five different FOVs and resolutions (voxel size) were taken from eight human dried mandibles in which the erosion-like lesions were created on both condyles. Imaging was performed before and after the formation of erosion; afterwards, the images were evaluated by two maxillofacial radiologists to analyze the absence or presence of the lesions. Resultant data was evaluated by SPSS V. 22.0, McNemar and Kappa statistical methods. Results: The highest sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were attributed to 8 × 8 FOV and the lowest was attributed to 12 × 8 FOV. In analyzing different resolutions, the highest sensitivity, specificity, PPV, and NPV were attributed to high resolution (0.125 and 0.15 mm voxel size). There was no statistically significant difference between sensitivity, specificity, PPV, and NPV of different FOVs and different resolutions. Inter-observer and intra-observer cofficiency were at excellent range. Conclusion: Considering there was no significant difference between the results, it is possible to use voxels in larger size to reduce patient's dose in order to detect mandibular condyle erosions. In addition, FOV with lower patient's dose is the method of choice.