مجله دانشکده دندانپزشکی مشهد
سال چهل و ششم شماره 1 (پیاپی 120، بهار 1401)

Impaction of maxillary canines is one of the common developmental disorders in all societies worldwide, including Iranian adolescents. It can bring about serious problems for adjacent teeth and the jaw. Therefore, early detection of this issue is of utmost importance. The present study aimed to determine the frequency and axial inclination of impacted canines based on OPG radiography in patients referred to Mashhad Dental School. In this descriptive, cross-sectional, and retrospective study which assessed 4,058 OPG radiographs in Mashhad Dental School, the prevalence of impacted canines was determined based on age, gender, region, the existence of other impacted teeth, and axial inclination based on Yamamoto’s classification system. Moreover, the relationship of gender with impacted tooth region and existence of other impacted teeth. A p-value of 0.05 was considered statistically significant. Out of 4, 058 OPG radiographs, 38 (0.94%) cases had maxillary canine impaction. The abundance of impacted canines was higher in women (57.9%) than men (42.1%) and in the age range of 16-20 years. Regarding association with other impacted teeth, the highest frequency was related to the mandibular third molar (38.46%). Out of 38 cases of impacted canines, the most frequent type was type II impaction (58.3%). The results of the Chi-Square test demonstrated that gender was not significantly correlated with the impacted tooth region and the existence of other impacted teeth. As evidenced by the obtained results, the prevalence of maxillary canine impaction in the study population was high, and therefore, the impaction of this tooth should always be considered in radiographic images, especially in routine examination duration adolescents and adults.

Lichen planus is a relatively common chronic inflammatory mucocutaneous disease with unknown etiology and pathogenesis. Dyslipidemia caused by chronic inflammation results in the formation of atherosclerotic plaques which is associated with the risk of cardiovascular diseases. There is a dearth of studies with conflicting results in this regard; therefore, the present study aimed to compare the lipid profile as a risk factor for cardiovascular disease between patients with oral lichen planus and healthy people. This case-control study was conducted in 2019. Firstly, the aim of the study was explained to the patients and written consent was obtained. Thereafter, the patients' blood pressure and body mass index (BMI) were recorded in the data collection form. The patients were referred to the laboratory to check their cholesterol (HDL, LDL) and triglyceride levels. Data were analyzed in SPSS software (version 18) using the Mann-Whitney U test to analyze the data and compare the indicators in the two groups. The mean age scores of the participants were obtained at 46.7±16.9 and 41.5±10.1 years in the Liken Plan oral and control groups, respectively, and they did not differ significantly (P=0.59). There was a statistically significant difference between the two groups in terms of LDL and HDL, and the rates of LDL and HDL were higher in healthy people and OLP patients (P=0.036 and P=0.04, respectively); nonetheless, they were in the normal range in both groups. Dyslipidemia was normal in patients with OLP, and oral lichen planus did not appear to be a single risk factor for dyslipidemia.

Caries happen by the interaction between microorganisms causing caries and carbohydrates on the tooth surface. Studies show the presence of Streptococcus mutans and Lactobacillus acidophilus bacteria in caries lesions. Considering the relative resistance to antibiotics among bacteria and given the antibacterial effect of Citrullus Colocynthis, this study aimed to evaluate the antimicrobial effect of this plant.

After preparing the extract by the maceration method, serial dilutions of 1:2, in which each concentration contains an active ingredient equal to half of its previous concentration, were prepared from 16384 to 8 µg/ml. Afterward, in each plate, 100 μl of different concentrations of extracts, culture medium (2×), and standard bacterial suspension were added. The plates were incubated in an anaerobic jar at 37°C for 48 h. Following that, minimum inhibitory concentration was determined by observation.

Ethanolic extract inhibited the growth of Lactobacillus acidophilus at the concentration of 16384 µg/ml, and the aqueous extract inhibited the growth at the concentrations of 16384 and 8192 µg/ml. The ethanolic and aqueous extracts inhibited Streptococcus mutans growth at the concentrations 16384 and 8192 µg/ml.  

The inhibitory effect of ethanolic and aqueous extracts of Citrullus colocynthis on Streptococcus mutans was the same, and considering that only very high concentrations have antibacterial effects, none of the extracts had antibacterial effects on this bacterium. Regarding Lactobacillus acidophilus, none of the extracts had antibacterial effects on this bacterium.

Toothache is one of the most common complaints related to dental services. People may experience high levels of anxiety when visiting a dentist or avoid receiving services. The term dental anxiety is used to describe a specific type of anxiety caused by the dental environment. The present study aimed to investigate the psychological factors affecting dental anxiety.Materials &

The present study was conducted based on a descriptive-cross-sectional design. Participants were selected via convenience sampling. The sample in this study included 328 patients referred to dental clinics in Kermanshah in 2020-2021. The instruments used in this study included the Pain Anxiety Questionnaire (PASS-20), Dental Anxiety Inventory (DAI), and Mental Pain (OMMP). Finally, after data collection, the data were analyzed in SPSS software (version 24) using Pearson correlation and multiple regression analysis.

Based on the results of the Pearson correlation coefficient, pain anxiety showed a positive and significant correlation with dental anxiety (r=0.45) and mental pain (r=0.25) (P=0.001). Based on the results of multivariate regression analysis (Enter), pain anxiety (β=0.356) and mental pain (β=0.139) were significant predictors of dental anxiety (P<0.05).

As evidenced by the results of the current study, it can be concluded that psychological factors, such as pain anxiety and mental pain, are effective in dental anxiety. Furthermore, a great deal of pain anxiety can increase dental anxiety due to people’s distorted perceptions of dental services.

Passing through the traditional methods of impression making and using the latest technology of digital scanners forces us to compare the positive and negative characteristics of these tools with those of the usual methods adopted in dentistry. One of the most important concerns regarding digital formatting is the accuracy of these scanners. This laboratory study was conducted to evaluate the effect of the topography of the prepared tooth and the location of the tooth in the maxillary arch on the accuracy of the intraoral scanners, taking into account the parameters of precision and trueness.

In this study, two canine and molar mandibular teeth were used, which were prepared for all-ceramic restoration. The use of ceramic die in this study provided us with the advantage of eliminating the need to use powder. Each ceramic sample was scanned 10 times by CEREC Omnicam and 3Shape Trios 3 scanners. The reference scanner was Open Tech. Finally, using the software, the STL format of the scans was prepared, and the obtained data were compared with the study reference scanner to assess precision and trueness. Statistical analysis of data was performed to find the differences using the Shapiro-Wilk test and paired t-test.

The results of the present study showed that in the molar teeth, the highest value and mean of the precision and trueness parameters were observed in the 3Shape Trios 3 scanner. However, the CEREC Omnicam scanner showed the lowest value and mean ​​of precision and trueness. No significant difference was observed between the two types of scanners in canine teeth in terms of mean precision and trueness.

It can be claimed that in preparing the molar tooth for an all-ceramic restoration by intraoral scanners in the molar tooth, the 3Shape Trios 3 scanner was more accurate than the CEREC Omnicam. Nevertheless, there was no such significant difference in canine teeth.

Successful endodontics training is the integration of students' skills and knowledge as the basis for mastery and competence in the work. Therefore, they can perform satisfactory non-surgical endodontic treatment on single-rooted and multi-rooted teeth. The present study aimed to determine the results and evaluate the success rate of endodontic treatment to improve the outcome of treatment conducted by general students of Mashhad Dental School in 2011-2012.

A total of 70 records of treated patients were reviewed by students, and they were recalled for follow-up. The success of endodontic treatment was firstly assessed based on clinical criteria and then based on radiographic criteria in one of three groups: success, failure, and unknown. Other factors including age, gender, tooth area, jaw, post-restoration, causes of inappropriate treatment, and student’s educational level that could affect success were also assessed.

In the present study, 74.3%, 20%, and 5.7% of treatments were successful, failed, and unknown, respectively. Twelve (17.1%) teeth were extracted. The highest success rate was observed in health restoration and it was clinically significant (P=0.076). Age, gender, type of teeth, and jaw also had no significant effect on treatment outcome (P> 0.05). Only a significant association was observed between students' courses and the success rate of treatment (P <0.05). Also, the highest success rate was seen in proper root canal treatment and health restoration (96.4%), but there was no statistically significant association (P=0.448).

The success rate of the 70 endodontic treatments performed by undergraduate students from Mashhad dental school was 74.3%. Proper restoration after root canal therapy is a factor affecting the treatment results.

The present study aimed to determine the effect of different disinfection procedures on the dimensional stability of condensational silicone impression materials.

In this laboratory study, 84 impressions of an aluminum die were made with condensation silicone impression materials. The impressions were assigned to four groups of 21 based on the disinfection procedures: immersion in the 5.25% sodium hypochlorite, immersion in 2% glutaraldehyde solution, and the use of spray deconex. The impressions which were not disinfected served as controls. After treatments, impressions were poured, and respective stone casts were measured and compared with the aluminum die at three dimensions of mesiodistal, occlusogingival, and buccolingual, as well as the space between two dies. The obtained results were reported by ANOVA.

Based on the results, 5.25% Sodium hypochlorite and deconex showed the most significant dimensional changes in terms of increasing die height. Moreover, in terms of the distance between the two dies, sodium hypochlorite demonstrated the least dimensional changes and did not differ from the control group. Sodium hypochlorite solution led to a significant increase in buccolingual and mesiodistal dimensions of die. Nonetheless, the glutaraldehyde solution reduced these dimensions. The dimensional changes of the deconex group and the control groups were not significantly different.

The impressions of the control group showed the least dimensional changes of buccolingual, mesiodistal, and height, and also there was no significant difference between control and sodium hypochlorite groups in terms of the distance between the two dies. The use of glutaraldehyde in clinical practice is recommended for the disinfection of impressions that have been fabricated for the fixed single crowns.

Geographic tongue is the inflammation of the dorsal surface of the tongue with no definite etiology. In this study, salivary levels of cortisol and α-amylase in participants were measured to investigate the correlation of stress-related biomarkers with the occurrence of geographic tongue.

In this case-control study, unstimulated saliva samples of 90 participants (45 patients with geographic tongue and 45 control subjects) were collected, and the level of cortisol and alpha-amylase were measured, subsequently. Data were analyzed using SPSS software (Version 20) through Student’s t-test. A p-value less than 0.05 (P˂0.05) was considered statistically significant.

Salivary alpha-amylase level was obtained at 116.7±8.2 (u/ml) and 114.6±8.7 (u/ml) in patients with geographic tongue and the control group, respectively, indicating no significant difference between the two groups (P=0.8). Moreover, the level of salivary cortisol was obtained at 4.8±2.3 (ng/ml) and 6.9±3.4 (ng/ml) in the groups of control and case, respectively, which indicated a remarkable increase in the case group (P=0.001).

Although the level of salivary cortisol was higher in patients with geographic tongue, no significant relationship was observed between the risk of geographic tongue and alpha-amylase level. However, the evaluation of the correlation between geographic tongue and stress requires more clinical and para-clinical examinations.

Due to the increasing rate of implant surgery, the present study aimed to determine the effect of informing patients about implant surgery and details of the treatment on their pain and anxiety level.

In this clinical trial, patients' level of anxiety was initially determined by DAS-R (Dental Anxiety Scale, Revised) questionnaire; thereafter, only the patients with moderate and high levels were included. A total of 22 eligible patients were randomly assigned to two groups. In the study group, the patients were provided with a pamphlet containing basic information and details of operative procedures using, whereas this information was withheld in the control group. The state anxiety (SA) index was used to assess anxiety before and after surgery. Pain during and one week after surgery was assessed using the Visual Analogue scale (VAS) index. Patient satisfaction with the treatment process and the dentist’s satisfaction with the convenience of the procedure were determined and compared between the two groups one week after the intervention. Data were analyzed using T-test, Mann-Whitney, paired t-test, and Pearson correlation coefficient. (α=0.05 as a significance level)

Based on the results, the two groups did not significantly differ in terms of the mean anxiety before and after surgery, as well as pain during and after the trial (P= 0.49, 0.57, 0.65, 0.51, respectively). Furthermore, dentist convenience (P=0.193) and patient satisfaction (P=0.611) were not significantly different between the groups.

As evidenced by the results of this study, there were not any significant differences between the two groups in the assessed variables; nonetheless, the experienced anxiety in both groups was lower than anticipated.

The anxiety of children and their lack of cooperation during dental treatments have made their behavioral management a great challenge for dentists and families. This study aimed to introduce a new technique in children's behavioral guidance called "Prize-Distraction" and compare its efficacy with a "conventional distraction" technique.

This case series study was performed on the dental treatment of three cases (two boys and one girl) using behavioral guidance methods of "Prize-Distraction" and "Story-Telling Distraction" with a split-mouth (cross over) design. The children's behavioral reactions were evaluated using the "Sound Eye Motor (SEM)" scale during local anesthesia injection and tooth extraction procedures. Our results showed that the samples showed fewer behavioral reactions during the treatment using the "Prize-Distraction" method, compared to the "Story-Telling Distraction" technique.

In all three cases, the results of the sum of SEM scores at different times when using the "Prize-Distraction" technique were lower than those in the other technique. It seems that the "Prize-Distraction technique" can have promising results in guiding children's behavior during dental procedures. Further studies are needed to evaluate the effectiveness of this new technique.