Journal of Dentistry
Year:2021 | Volume:22 | Issue:3|Papers Count:12

Statement of the Problem: Studies on the efficacy of erbium laser for enhancement of enamel resistance to acid attacks and its effects on fluoride uptake by the enamel are limited. Purpose: This study sought to assess and compare the effects of erbium-doped yttrium alu-minum garnet (Er: YAG) laser irradiation and application of acidulated phosphate fluoride (APF) gel (alone and in combination) on remineralization of artificial white spot lesions (WSLs). Materials and Method: This in vitro, experimental study evaluated 90 buccal and lingual slabs of extracted human premolars. The specimens underwent pH cycling to induce WSLs. They were then randomly divided into 6 groups of caries-free positive control (c+), negative control with WSLs (ws), 1. 23% APF gel applied on the enamel (F), Er: YAG laser irradiation (80 mJ, 10 Hz, and 8 J/cm2) of enamel (L), APF gel application followed by laser irradiation (FL), and laser irradiation followed by fluoride gel application (LF). The fluoride ion content of specimens was measured before and after the intervention using a potentiometer. Data were analyzed by ANOVA (p< 0. 05). Results: APF gel application before/after laser irradiation maximally increased the fluoride uptake by the enamel (p= 0. 000). Application of APF gel in group F and laser irradiation in group L increased fluoride uptake by the enamel, compared with groups 1 and 2 (p= 0. 000). Laser-treated (L) and APF-treated (F) groups had no significant difference in this respect (p= 0. 945). Maximum fluoride concentration was noted in combined laser and fluoride groups (FL=332. 07ppm and LF=341. 27ppm) with no significant difference between the two (p= 1. 000). Conclusion: Er: YAG laser irradiation changes the chemical composition of enamel and probably promote its remineralization, especially when combined with APF gel application, which highlights its cariostatic potential.

Statement of the Problem: The efficacy of photodynamic therapy (PDT) in smear layer removal compared to the currently accepted protocol is not well established. Purpose: This study aims to evaluate the effect of PDT on smear layer removal from human root canal compared to combined use of irrigation solutions including sodium hypochlorite (NaOCl) and ethylene diamine tetra acetic acid (EDTA) by scanning electron microscopy (SEM). Materials and Method: In this in vitro study, straight roots from 48 extracted human maxil-lary incisors and canines were selected and decoronated. Instrumentation was completed with RaCe rotary system and normal saline irrigation between files. Then roots were randomly divided into 3 groups (n=16). Group 1 was the control group to confirm smear layer for-mation. In the group 2, the canals were irrigated with 2ml of 2. 5% NaOCl solution for 10 minutes and 2ml of 17% EDTA solution for 1 minute. In the group 3, PDT with methylene blue and diode laser (625nm, 150mW, for 5minutes) was the final procedure for smear layer removal. All the specimens were sectioned into two halves, gold coated, and analyzed under SEM. The smear layer in the coronal, middle, and apical thirds, were evaluated and scored by two examiners independently. Statistical analysis was done using Chi-square test. Results: It was observed that the NaOCl+EDTA removed the smear layer significantly better than PDT in the coronal and apical thirds (p< 0. 05) whereas PDT was unable to remove the smear layer in none of the root areas. At the apical thirds, there was no significant difference between NaOCl+EDTA and PDT (p< 0. 05). Both procedures were unable to remove smear layer from radicular dentine of this area. Conclusion: According to the results of this in vitro study, the use of PDT alone is not rec-ommended to remove smear layer. The combined application of NaOCl and EDTA is ineffec-tive in removing smear layer of apical third, despite its efficacy on the coronal and middle regions.

Statement of the Problem: Need assessment is considered as a key element of health care planning. Subjective measures can be useful tools in epidemiologic surveillances. Purpose: The aim of study was to evaluate inequality in perceived unmet oral health need (PUOHN) in adults in east of Iran. Materials and Method: In this cross-sectional population-based study, the target popula-tion included adult residents in the Mashhad and Kerman city. Data was collected through telephone interviews using a validated structured questionnaire. Phone numbers were ob-tained from telecommunication company. Participants were selected by stratified random sampling. Predisposing and enabling variables associated with PUOHN were included gen-der, age, educational level, job, insurance coverage, dental insurance, type of insurance, residential location, household size, and family economic indicators. Logistic regression was used to examine association of PUOHN and predisposing and enabling factors. Results: 1475 individuals participated in the study (response rate of 63%). 52% of partici-pants stated that their dental needs have not been met during the past year. The mean ages of respondents were 39 years old and 69. 8% were female. Logistic regression analyses indicat-ed living in rental house [OR=2 (95% CI 1. 25-3. 21), p Value=0. 004] and higher household size [OR=1. 19(95% CI 1. 003-1. 43), p= 0. 04] significantly associated with PUOHN. Conclusion: The results of this study indicated high PUOHN in the adult population of East Iran. Effective strategies must be implemented to provide accessible dental services regard-less of socioeconomic status.

Statement of the Problem: Traditional clinical criteria are usually not sufficient for determin-ing the sites of active periodontal disease, monitoring the response to treatment, or measuring the susceptibility to future disease development. Past studies have shown that heat shock pro-tein 70 (HSP70) are involved in the etiology of periodontal disease. Purpose: The aim of this study was to evaluate the level of HSP70 in saliva of patients with chronic periodontitis (CP). Materials and Method: In our case-control study, the saliva samples of 45 patients with CP and 45 age-and sex-matched healthy subjects were collected. Salivary HSP70 was measured by enzyme-linked immunosorbent assay method. The results were analyzed by statistical tests using SPSS 16 and the statistically significant difference was set at p< 0. 05. Results: In this study, the mean salivary HSP70 level was 2. 81± 0. 61ng/ml in the patient group and 1. 96± 0. 77ng/ml in the healthy group, with a significant difference (p< 0. 05). In addition, the results of spearman correlation analysis showed a positive correlation between salivary HSP 70 and clinical periodontal index. Conclusion: The results of this study showed that the salivary HSP70 level in patients with CP is higher than that in healthy subjects. As a result, salivary HSP70 might be considered as a marker in the pathogenesis of CP.

Statement of the Problem: The association of genetic polymorphisms with periodontitis has been studied extensively. The interleukin-17 (IL-17) is a group of cytokines, which comprises six different molecules (IL-17A, B, C, D, E & F). Among these, IL-17A & F are the most commonly understood cytokine, which plays a critical role in inflammatory diseases and peri-odontal inflammation. Purpose: To evaluate whether IL-17A gene polymorphism is associated with increased risk of chronic periodontitis in type 1 diabetes patients. Materials and Method: This quantitative case-control study was carried out in 60 subjects in 4 groups. The study groups included group A: 15 type 1 diabetes patients (T1DM) with chron-ic periodontitis (CP), group B: 15 T1DM patients without CP, group C: 15 Non-diabetic pa-tients with CP, group D: 15 Non-diabetic patients without CP. Blood samples were drawn from the subjects and analyzed for IL-17A polymorphism by using the polymerase chain reaction-restriction fragment length polymorphism method. Results: There was no statistical significant difference seen in the genotype distribution among CP patients with or without T1DM and healthy controls. Odds ratio and p value indi-cated that increased risks for CP were associated with IL-17A allele (G) in patients with T1DM. This allele was correlated with worse clinical parameters of CP in T1DM patients. Conclusion: The present study revealed that IL-17A (rs2275913) polymorphism was not associated with increased risk for CP in T1DM patients.

Statement of the Problem: The stimulation of odontogenic activity is considered an essen-tial property for biomaterials used in vital pulp therapy. Purpose: The present study aimed to evaluate the effect of the incorporation of zeolite con-taining silver-zinc nanoparticles (Ze-Ag-Zn) into Angelous mineral trioxide aggregate (AM-TA) on the odontogenic activity of human dental pulp stem cells (HDPSCs). Materials and Method: In this in vitro study, HDPSCs were treated with 2% wt of synthe-sized Ze-Ag-Zn particles+AMTA, AMTA and Ze-Ag-Zn disks. The negative control cells did not receive any treatment. Then, cell viability was measured using the MTT assay after 7 and 14 days of the treatment course. The alkaline phosphatase (ALP) activity and calcium ion level were also measured in the supernatant culture media using auto-analyzer kits. The obtained data were analyzed using one-way ANOVA and Student t-test where appropriate. The level of the statistical significance was set at p< 0. 05. Results: The results indicated that HDPSCs treated with AMTA and AMTA+Ze-Ag-Zn particles did not show any significant cell death compared with the control cells after 14 days of the treatment course while the ALP activity and calcium ion levels were significantly (p< 0. 05) elevated. Also, the addition of AMTA particles to the cell culture media resulted in increased ALP activity and calcium ion level compared with HDPSCs treated with AMTA+ Ze-Ag-Zn particles on day 7 of the treatment course (p< 0. 05). Conclusion: It seems that the incorporation of Ze-Ag-Zn particles into AMTA did not have any significant positive effect on the biomineralization properties of AMTA.

Statement of the Problem: The extrusion of intracanal debris is one of the challenging problems related to almost all root canal preparation systems, which may cause flare-ups and impairment in the healing process. Purpose: This study was conducted to evaluate the amount of apically-extruded debris during root canal preparation using Medin (MEDIN Co., Czech Republic) rotary system compared with two common rotary systems, including ProTaper (Dentsply Maillefer., Swit-zerland) and RaCe (FKG Dentaire, Switzerland). Materials and Method: In this in vitro study, Sixty mandibular premolars with single canal were randomly assigned to three groups (n=20). The root canals were prepared with Medin, ProTaper, and RaCe rotary instruments based on their manufacturers’ instructions. The debris were collected into pre-weighted Eppendorf tubes. The weight of the extruded debris was calculated by subtracting the pretreatment weight of the vials. Data were analyzed using the Kruskal-Wallis test at a 5% significance level. Results: Medin instrument caused significantly less debris extrusion in comparison with ProTaper and RaCe (p< 0. 05). The differences between the ProTaper and RaCe rotary sys-tems were not statistically significant (p= 0. 752). Conclusion: Within the limitations of this in vitro study, Medin rotary system produced less apical extrusion than ProTaper and RaCe.

Statement of the Problem: Intraosseous lesions of jaws can be imaged by cone beam computed tomography (CBCT) and ultrasonography (USG). The knowledge of imaging features of these two methods about intraosseous jaw lesions is important for dental radiology. Purpose: The aim of this study is to evaluate artificial mandible intraosseous lesions by using CBCT and USG. Materials and Method: In this in vitro study, intraosseous lesions containing water, milk, olive oil, and liver were evaluated in 60 artificial mandibles by using CBCT and USG. Lesion sizes were compared between CBCT and USG. Lesion sizes were measured on the anterior-posterior, bucco-lingual, and superior-inferior sides. Hounsfield unit (HU) values of the lesions in CBCT images were compared between different materials. Echogenicity of the lesions were evaluated in USG images. One sample t and one-way Anova tests were used for the statistical analysis of the study (p˂ 0. 05). Results: In all size measurements of the lesions, mean CBCT values were statistically high-er when compared with USG. In CBCT images, statistically difference was found between the HU values of lesions containing olive oil and other lesion contents. In USG images, echogenicity of water, milk and olive oil was found to be anechoic and the echogenicity of liver was found to be hypoechoic. Conclusion: CBCT was found to be more accurate than USG in measurement of the size of mandibular intraosseous lesions. According to the results of our study, it was thought that only oil content could be differentiated by using CBCT HU values. It was found that lesions with liquid and non-liquid contents could be differentiated with their echogenicity difference in USG images.

Statement of the Problem: Oral health is one of the most important public health prob-lems. The DMF index is used to assess oral health status. Purpose: This study was performed to evaluate oral health status based on DMF index in adults in Fars province. Materials and Method: This cross-sectional study was performed on 8911 people aged 40 to 70 years under the Kharameh cohort study in 2020. Demographic and oral health factors were collected during interviews and clinical evaluation. T test, ANOVA, and linear regres-sion tests were used for data analysis. Results: The mean and standard deviation of DMF index was 18. 06± 8. 7in all individuals under study. Multiple linear regression results showed that diabetes (OR=1. 1 95%CI: 0. 9-1. 9 p= 0. 0001), smoking (OR=4. 4 95%CI: 4-4. 9 p= 0. 0001) and underweight (OR=2. 1 95%CI: 1. 1-3. 1 p= 0. 0001) are the factors affecting the increase in DMF index. Other fac-tors such as high level of education, economic and social class, flossing, and living in a village have been inversely related to the DMF index. Conclusion: The results of this study are a warning about the importance of reducing dental costs to increase the level of access of people with low economic and social levels and in-crease health literacy in relation to oral health.

Statement of the Problem: The inferior alveolar canal (IAC) is a bony canal that starts from mandibular foramen at the inner surface of the mandibular ramus and extends along the ramus and body of mandibular bone in forward and downward directions to the mental foramen. Inside the mandibular canal, there are lower alveolar artery and a nerve with the same name. Understanding the anatomical details of the lower alveolar canal, including position, pathway and morphology to prevent complications in surgical procedures in the lower jaw such as mandibular impacted molar surgeries, mandibular nerve block injection, or even root canal treatment of mandibular teeth is important. Purpose: The purpose of this study was to investigate the course and direction of IAC in mandibular bone and its relation to anatomical factors such as gonial angle and location of entrance of IAC in the mandibular ramus. Materials and Method: This cross-sectional study evaluated a sample of 280 digital pano-ramic images. All samples were Iranian. The pattern and direction of the IACs were record-ed according to age and gender and the relation of these patterns to the gonial angle of man-dible and the entry point of the IAC in mandibular ramus were evaluated. Results: The results showed that the course of canal, the entrance point of the canal and the gonial angle were the same between different age groups and between two genders. There was no significant relation between the course of canal and the two anatomical variables mentioned (p> 0. 05). Conclusion: Considering the increasing frequency of implant surgeries and presence of different courses of the mandibular canal and concerning the important complications such as paresthesia caused by damage to the mandibular nerve, panoramic radiography is neces-sary before any surgery in this area to avoid unwanted injuries to the neurovascular system if other advanced modalities are not available.

Castleman‟ s disease (CD), otherwise known as angiofollicular lymph node hyperplasia, is a rare, poorly understood disorder, which often occurs in a mediastinum. Involvement of parotid gland is a considerably infrequent event. We present a 15-year-old boy patient with a swelling in the left parotid gland that has been diagnosed with CD. The clinical features, radiographic findings, and treatment plan are discussed. Furthermore, a thorough literature review demon-strated 57 published cases of CD in salivary gland with their summarized features.

Proper knowledge of the anatomic structure of the root canal system is a vital prerequi-site for successful root canal therapy. This report presents the endodontic management a two-rooted lower first premolar with five root canals. A similar case has not been report-ed to date. The use of cone beam computed tomography (CBCT) in rare and doubtful cases helps establish an accurate diagnosis and render successful endodontic treatment thereafter. This article helps broaden our knowledge about the possible anatomic diversi-ties as to teeth with more roots and root canals than expected normally.