Journal of Dental School, Shahid Beheshti University of Medical Sciences

Objectives Treating and accelerating the healing of oral ulcers caused by various surgeries or injuries have long been important to avoid financial loss and mental harm. Fibroblasts play an important role in wound healing. The current study aimed to produce a suitable synthetic material using cuttlebone and investigate its effect on gum fibroblast cells to help accelerate the healing of oral ulcers.  

Methods Chitin powder was extracted from squid bone (cuttlebone) to produce a synthetic material, which was subjected to physicochemical control tests. To make the samples, human gingival fibroblasts were cultured in a suitable medium and divided into four groups, namely chitin, gel, base (without active ingredient), and control groups. The effects of the produced synthetic material on the viability and proliferation of gingival fibroblast cells were investigated using MTT assay for 24, 48, and 120 hours. Data were analyzed using Dunnett's post-hoc test, Tukey's test, and one-way analysis of variance (ANOVA).

Results About 1.7 grams of chitin powder was obtained from 5 grams of cuttlebone powder. FTIR was used to identify chitin. A gel containing 1% chitin was selected. The results of MTT assay showed that the formulated gel had no toxicity, and the proliferation in chitin and gel groups increased over time compared to the control and base groups.

Conclusion It seems that using cuttlebone chitin to make a suitable gel-based synthetic material can accelerate the healing process of mouth ulcers.

Objectives Child labor is an important phenomenon affecting global health. However, studies concerning the oral and dental health of child laborers are limited. The present study aimed to assess the effectiveness of oral hygiene instructions in a group of child laborers under the protection of a charity.

Method In this cross-sectional interventional study, the sociodemographic information and the Oral Hygiene Index-Simplified (OHI-S) scores of a group of working children were collected. Oral hygiene tools were provided for the children, and proper instructions were given to them. After three months, the plaque index and the reasons for its non-reduction were gathered. Descriptive indices were calculated for data presentation.

Results A total of 79 child laborers (mean age, 11.8±1.29 years), including 30 females and 49 males, were evaluated in this study. Based on the results, 51 (64.6%) children had used a toothbrush at least once before the study. Three months after giving the oral health instructions and providing the oral hygiene tools, 12 children were removed from the study due to a lack of follow-up. Of the remaining 67 children, 34 had brushed their teeth at least once (64.7%) or twice (35.2%) a day. The OHI-S score reduction was statistically significant (P=0.013).

Conclusion According to the results, instructing working children on oral health and providing them with proper oral hygiene tools, such as toothbrush, toothpaste, and dental floss, could be effective in improving their oral health and could enhance their cooperation significantly.

Objectives Root fracture detection may be a challenging process due to difficulties in clinical and radiographic assessments. This study compared the diagnostic efficacy of Photostimulable Phosphor (PSP) intraoral digital receptor software alternatives for detection of vertical fractures in mandibular posterior teeth.

Methods In this diagnostic research, 60 human mandibular posterior teeth were chosen. Vertical fracture was induced on half of teeth using a hammer through a random method. Thereafter, the broken pieces were glued together using a superglue, and placed inside a sheep mandible. Next, utilizing a digital intraoral technique and a PSP sensor, radiographic images of every tooth were taken. All radiographies  were then subjected to computer adjustments such as sharpening, reverse-contrast, and enhancement. Three radiologists investigated the images of teeth after application of computer adjustments regarding existence of fracture. SPSS 22 was used for data analysis.

Results Among processed images, sharpness had the highest accuracy (89.3%) followed by enhancement (89%), and reverse-contrast (87%). Statistically, no significant difference was observed in diagnosis of vertical fractures of mandibular posterior teeth regarding sensitivity, specificity, accuracy, as well as positive and negative predictive value among main images (no effect) and the images on which sharpness, reverse-contrast, and enhancement by software were applied (P-value>0.05). For intra-observer agreement, Kappa value > 0.70 and for inter-observer agreement, kappa value=0.50-0.7 were found.

Conclusion Usage of sharpness, reverse-contrast, and enhancement software had no significant impact in diagnosing vertical root fracture of multi-rooted teeth (P-value>0.05).

Objectives Health workers are considered as an important part of society and a role model for service recipients. Quality of life related to oral health is a common concept to assess the impact of oral conditions and the impact of dental interventions that affect people in many aspects such as physical, mental, social and ability to perform daily activities of life. The aim of this cross-sectional study was to assess the quality of life related to oral health among the staff of Shahid Beheshti Dental School.

Methods This study was performed on 85 employees of Shahid Beheshti Dental School in 2021. The Participants completed the OHIP-49 (Oral health impact profile-49) questionnaire. Independent t-test, and one way ANOVA were used for data analyzing by SPSS 21 statistical software.

Results The mean total score of OHIP was 13.86 with a standard deviation of 12.44. The most problematic subscale physical pain (20.65±14.01). The psychological disability and social disability subscales were significantly associated with female gender (p<0.05), and there was no relationship between the mean OHIP scores and the rest of measured demographic variables, including age, marital status, level of education, and chronic disease.

Conclusion The results of the study showed that the quality of life related to oral health in dental staff was acceptable. On other hand, the Persian version of OHIP-49 questionnaire was validated to be used in Iran.

Objectives Tooth decay is a common disease of childhood. If the pH level in the mouth repeatedly falls below 5.5 for an extended period of time, dental demineralization can eventually result in tooth decay or caries. Yogurt is a fermented milk product that is consumed all over the world. In this study, we aimed to compare salivary pH changes in children aged 6-12 years following the consumption of plain, probiotic, and fruit yogurt.

Methods A total of 51 children were randomly allocated into three groups of 17 people. On the day of the experiment, a sample of primary non-stimulating saliva was obtained from each participant one hour after breakfast. Next, the participants were given 10 cc of selected yogurt, including peach, probiotic, and plain yogurt, all of which were produced by the same company. After 10 minutes, another salivary sample was obtained from each participant. The pH of both samples was calculated using a measuring device, and the difference between the two measurements was considered as the amount of pH change. Analysis of variance (ANOVA) and paired t-test were used for between- and within-group comparisons, respectively.

Results There was a significant difference in the salivary pH level, based on the within-group comparison of peach and probiotic yoghurt groups (P=0.001), while no significant difference was found in the plain yoghurt group (P=0.366). Also, according to the between-group comparisons, significant differences were found between the peach and probiotic yoghurt groups (P=0.001) and also between the peach and plain yoghurt groups (P=0.001) in both comparison, peach group showed more decrease in PH level.

Conclusion Both fruit yogurt and probiotic yogurt can temporarily reduce the salivary pH levels. However, due to the lower critical point of demineralization, there are no concerns about the development of dental caries.

Objectives Chronic periodontitis is the most common type of periodontitis and a multifactorial disease in which a set of factors such as microbial plaque, environment, systemic conditions and genetics play a role in its development. Periodontal destruction occurs due to the host's immune response to microbial stimulation, which can lead to tooth loss. The purpose of the present study is to investigate the correlation between IL-6 gene polymorphism (rs1800795) and chronic periodontitis in an Iranian population.

Method This case-control analytical study was conducted on 54 patients with chronic periodontitis and 66 healthy individuals referred to the dental clinics of Shahid Beheshti, Zanjan, and Mashhad universities of medical sciences. After clinical examination and classification of subjects, blood samples (10 cc) were taken. The genomic DNA was extracted using salting-out method. The desired variant was amplified using PCR-RFLP method. Reaction products were analyzed after electrophoresis with 1% agarose gel. Data were analyzed with Pearson's chi-square and Hardy-Weinberg equilibrium tests, and P<0.05 was considered as the significant level.

Results The frequency of GG, GC, and CC genotypes was 41%, 44%, and 15%, in the patient group, and 36%, 42%, and 21%in the control group, respectively. There was no significant difference between the two groups in terms of the distribution of any of the inheritance patterns (P>0.05).

Conclusion The present study showed no relationship between IL-6 gene polymorphism (rs1800795) and chronic periodontitis in the studied population.

Objectives Periodontitis is a multifactorial disease in terms of etiology, including microbial, environmental, systemic, and genetic factors, and the host's immune response causes periodontal destruction. The present study was done to investigate the association between rs4986790 polymorphism of the TLR4 gene with chronic periodontitis in an Iranian population.

Method The present case-control study was conducted on 120 people, including two groups of control (n=66) and patient (n=54) in 2022. A periodontist evaluated the periodontal condition of the people, 5 milliliters of blood sample was taken from participants, gene sequence was determined using the PCR-RFLP method, and statistical analysis was performed using the chi-square test to determine the association between the disease and the mentioned polymorphism.

Results 64 participants (53.33%) were male, and the rest were female. The frequency of the A allele was 89% in the patient group and 90% in the control group, and the frequency of the G allele was 11% in the patient group and 10% in the control group. Also, the frequency of AA and AG genotypes was 78% and 22% in patients, and 80% and 20% in the control group, respectively (P=0.65). There was no statistically significant association between the genders, the presence of a specific allele or genotype with the occurrence of the disease. The odds ratio (OR) of the developing periodontitis in the heterozygous group compared to the homozygous group was calculated to be 0.78% (P=0.65).

Conclusion There was no association between TLR-4 gene polymorphism and chronic periodontitis in the studied population.

Keywords TLR4 Receptor; Chronic periodontitis; Single nucleotide polymorphism

I am Writing to share my professional opinion regarding the application of Artificial intelligence (AI) in oral and maxillofacial radiology. Intelligent systems (i.e., AI), are machines able to mimic the cognitive functions of humans to perform tasks of problem-solving and learning. AI is becoming important in radiology due to its ability to detect abnormalities in radiographic images. These systems have reduced radiologists’ workload by rapidly recording and presenting data, and thereby monitoring the treatment response with a reduced risk of cognitive bias. Some of the most common applications of AI in dentomaxillofacial radiology are: tooth and implant classification and identification, 3D cephalometric landmark detection, lesion detection (periapical, jaws, and bone), and osteoporosis detection. Therefore, these intelligent systems have an important role to play and could be used by dentists as an adjunct to other imaging modalities in making appropriate diagnoses and treatment plans.

However, AI potentials and pitfalls should be thoroughly assessed especially in critical cases, and it seems even when achieving high success rates, radiologists’ supervision is necessary in most cases.