مجله دانشکده دندان پزشکی اصفهان
سال شانزدهم شماره 4 (پیاپی 73، زمستان 1399)

 Oral cancer is one of the most common cancer types and is among the top ten leading causes of death in the world. Chemotherapy often results in bone marrow suppression, and reducing leukocytes it weakens the immune system. This study was conducted to examine general dentists and senior dental students' awareness of dental precautions before, during and after chemotherapy in the year 2018.

 The present study is a cross-sectional analytic one and, as far as the kind of research is concerned, it is an applied study. The data was collected based on field data collection method using a standardized self-report questionnaire whose measures of validity and reliability had been evaluated and confirmed to be adequate in previous studies. The population of the study comprised all of the general dentists (n = 1000) and senior dental students (n = 190) in Isfahan, and the sample comprised 140 participants. Data were analyzed via SPSS 22 software, and Chi-square.

 Among the students, the lowest and highest scores of awareness level turned out to be 7 and 16, respectively; however, among the dentists, the lowest observed score was 6, and the highest observed score was 16. The results indicated that the awareness level of the dentists and students under study was average. The mean knowledge score was 11.53 ± 25 and 11.74 ± 1.9 of 20 in dentists and students. There was no statistically significant relationship between the variables under investigation in this study (gender, age, years of job experience, the time passed since their dental private offices started to work) and the participants' level of awareness.

 The dentists and students were not aware enough. The dentists and students' lack of motivation and their unawareness of the important role of both early diagnosis of cancerous or precancerous lesions and being aware of dental precautions for patients who undergo chemotherapy are among the reasons justifying the lower than expected awareness level of the dentists and dental students in this study.

Tooth structure is exposed to continuous demineralization and remineralization in mouth. Balance between demineralization and remineralization depends on salivary concentration of calcium, phosphate and alkaline phosphatase. The aim of this study was to investigate the effect of chewing gum containing CPP-ACP on salivary concentration of calcium, phosphate and alkaline phosphatase in 7-11 years old children with severe caries.

In this analytical-descriptive study, 64 students through randomized sampling were chosen and divided into 2 groups of caries free and severe caries. Three saliva samples were gathered from participants, two hours after breakfast, 5 and 20 minutes after chewing of CPP-ACP gum. The samples were sent to laboratories were analyzed to find calcium, phosphate and alkaline phosphatase content. Data analysis was done by using the paired sample t-test, independent sample t-test at significance level (p value = 0.05) and the SPSS software, version 22.

The average concentration of salivary calcium in both groups caries free and severe caries of the participants, in the two time intervals after chewing gum, 5 and 20 minutes significantly increased (p value < 0.05). The average concentration of Salivary phosphate and alkaline phosphatase in both groups of 5 and 20 minutes, significantly decreased (p value < 0.05).

Chewing gum containing CPP-ACP can remineralized the tooth by increasing calcium and decreasing phosphate and alkaline phosphatase.

 Although using panoramic images of the third impacted molars and assessing their proximity to mandibular canal, this technique has limitations such as two-dimensional nature and magnifications occurred which calls to use a three-dimensional radiographic modalities such as CBCT. This study compared the location of the mandibular third molar’s roots regarding the inferior alveolar canal using panoramic radiography and CBCT techniques.

 In a descriptive-analytical trial, 103 radiographic images of the patients’ impacted mandibular third molars were selected from the archives of Radiology Department of Tehran Dental School and assessed by means of panoramic and CBCT techniques. Three oral & maxillofacial radiologists assessed the positions of the mandibular third molars’ roots regarding the inferior alveolar canal in the panoramic and CBCT images at 2 time intervals. The assessments were repeated for next 2 weeks again. And then they were done on CBCT images. Frequency and percent of panoramic signs indicating the proximity of the mandibular third molars regarding buccal, lingual and medial positions of the teeth were obtained among the observers and 2 time intervals and the results were statistically analyzed by chi-square test. Significance level was considered to be 0.05 (p value = 0.05).

 Of total 103 impacted mandibular third molars, 56 (54.4%) had lingual location, 25 (24.3%) had medial location and 22 (21.3%) shoed buccal locations of the roots towards mandibular canal. (p value < 0.002) The frequency of the root deflections (p value < 0.003), diversion of canals (p value < 0.03), narrowings of the roots (p value < 0.005), interruption of the borders (p value < 0.006) and narrowing of the canals (p value < 0.04) were higher in the buccal positions of the third molar roots towards the mandibular canal compared to other positions. The differences were statisticaly significant in some cases. However, the frequency of darkening of the roots (p value < 0.04) was higher in the lingual positions of the third molars than other positions. The agreements of the obervers was acceptable when assessing the images regarding indices of the proximity of third molars’ roots and mandibular canal.

 Then, CBCT technique is a valuable tool to assess the location of the mandibular impacted third molars regarding the inferior alveolar canal. Using CBCT images of impacted third molars, the risk of damage to the alveolar nerve can be reduced.

 There are several factors involved in postponement of referral to the dentist, which can affect the child's co-operation during treatment. The purpose of this study was to investigate the reasons for postponement in referring to dentistry and its effect on anxiety and behavior of the child while working in dentistry.

 In this descriptive-analytical study, 96 children aged 5-10 years old living in Isfahan with more than 12 months delayed were included. Initially, the parents completed the questionnaire to the causes of delay in referring to the dentistry. Then the anxiety and behavior assessment of the child was filled with a Venham questionnaire by a dentist. Data were analyzed by Mann-Whitney, One-way ANOVA, and Kruskal-Wallis tests using SPSS 22 software. The significance level was less than 0.05.

 The high cost of treatment was the most important factor in postponing and prevention of dental pain was the most important factor in the referral. There was no significant relationship between delay and behavioral scores (p value = 0.523) and anxiety (p value = 0.499), but the results show that increase in delay rates, children show a higher anxiety score and a more negative attitude. There was a significant and reverse correlation between postponement and age of the child (p value = 0.002).

 It seems that the parents consider the most important factor for postponement dental treatment as a high cost of treatment. The higher the delay in referring to the dentist, the more anxiety the child will be during treatment, and the child will show a more inappropriate behavior.

 Various symptoms have been attributed to tooth eruption. Further, parents use different strategies to reduce or eliminate these symptoms. This study was aimed to evaluate parental information about eruption of primary teeth in Isfahan, Iran. 

 This descriptive, cross-sectional survey was conducted on 100 parents having six-month- to three-year-old children referring to the dental clinics or offices in Isfahan. A questionnaire with validated face and content validity was designed to collect data. It included questions about demographic characteristics, eruption time and the first erupted tooth, symptoms of eruption, and control of symptoms. Data were analyzed by frequency distribution, relative frequency, descriptive indices, and chi-square test via SPSS 22.0. p value < 0.05 was considered to be statistically significant.    

The most frequent symptoms parents agreed with included high tendency to bite and chew, high saliva flow, and gingival inflammation, respectively. Fever was the most frequent symptom the majority of parents disagreed with. The most frequent methods used by the parents included hugging the child and amusing the child. The most frequent disagreement was reported for the use of sleeping drugs. No significant correlation between parental information about tooth eruption and economic status, parental education, parental age, and number of children was found. (p value < 0.05) The mean score of parental information was 2.37 ± 0.97 and degree of response was 96%.   

Parents’ knowledge about tooth eruption was moderate and acceptable awareness on symptoms of tooth eruption and methods of decreasing the symptoms was found.

 Patients without teeth are most likely to face denture mandibular. Overdentures based on the mandibular implant lead to greater stabilization of the prosthesis, resulting in improved function and patient satisfaction. The aim of this study was to evaluate the effect of implant overdentures and the type of attachment on patients' satisfaction and quality of life.

 In this retrospective study fifty-nine patients who their overdentures had been under force for at least three years, were recalled. After conducting clinical examinations and completing the relevant form, they completed two forms, OHIP21 and VAS, to assess the quality of life of patients and their satisfaction with implant-supported overdentures. The data was entered into SPSS software. Kolmogorov-Smirnov Sample test was used to find data distribution. Also tests Kruskal-Wallis, Mann-Whitney and post hoc LSD were used to measure the results of the questionnaires (α ≤ 0.05).

 Gender does not have a significant effect on people's satisfaction and quality of life. Retention in ball and bar attachment and overall satisfaction in bar and clip attachment were significantly higher than locator. The type of attachment has no effect on implant anchorage problems and prosthetic problems.

 The level of satisfaction and quality of life of patients using implant-supported overdenture in mandible did not affected by gender. Also, the type of attachment could not affect the prosthetic and implant problems, and the quality of life improved with the increase in the number of implants.

 Bone remodeling is a continuous and complex process and it seems that the morphologic changes in mandible is under the influence of age and dental status of the patient. The Gonial angle is a region of mandible that affects from these changes. The aim of this study is the evaluation of Gonial angle size and its correlation with cortical thickness and height of mandibular residual body in various dental status by means of panoramic radiography.

 In this cross sectional study 252 panoramic radiographs of patients who went to Sari Dental School Clinic were examined. Dental status of patients was recorded in the form of relevant information and the patients were categorized in three different groups: Dentate, Partially Dentate and Edentulous group. Panoramic measurement was performed by using software DFW v2.8. All the data were analyzed by software SPSS v16 and descriptive statistics and methods of inferential statistics (p value < 0.001).

 The mean size of gonial angle in dentate, partially dentate and edentulous was 119.92 ± 3.79, 123.48 ± 3.43 and 127.14 ± 5.20 degrees. The mean height of cortical thickness in dentate, partially dentate and edentulous was 3.52 ± 0.73, 3.12 ± 0.54 and 2.86 ± 0.71 mm. The mean height of mandibular residual body in dentate, partially dentate and edentulous was 25.62 ± 2.50, 19.95 ± 3.07 and 14.75 ± 4.67 mm.

 Gonial angle size has an inverse ratio with cortical thickness and height of residual mandibular body

 The facial oral pain and symptoms of sinusitis is one of the concerns of patients especially dentists which can be associated with Haller cells. The aim of this study was to evaluate the prevalence of Haller cells of an Iranian population and its relationship with inflammatory sinus disease using CBCT images.

 In this descriptive- analytical research (in 2018) samples were selected from all available CBCT images of patients referring to Tabriz school of dentistry. Haller cells cases were selected and the samples were examined for the presence of inflammatory sinus disease in the coronal and axial sections. The data from CBCT images were entered in NNT viewer version 2.17 and the images were reviewed by two oral and maxillofacial radiologists. Then agreement between the two observers was measured by Kappa coefficient. Data were analyzed using SPSS 20 and Chi-Square test and p value < 0.05 was considered.

 For total sinuses, the prevalence of Haller cells was 44.5% and it was 70.3% for chronic sinusitis. Haller cells were 48.4% unilateral and 52.6% bilateral. There was no significant difference in the frequency of Haller cells between men and women. Statistical analysis showed there was significant correlation between Haller cells presence and sinusitis (p value < 0.05).

 According the results of this study, people with Haller cells are more likely to develop inflammatory sinus disease.

 Bacteria growing in dental plaque have increasing resistant to antimicrobial agents. The present study aimed for reduction of biofilm formation by streptococcus mutans isolated from dental plaque by protease enzyme.

 Streptococcus mutans from dental plaque was isolated in Blood agar medium and then was identified by biochemical tests and sequencing of 16S rRNA coding gene. Bacterial biofilms were formed in wells of microtiter plate in Triptic Soy Broth medium supplemented with 1% sucrose after 48 hrs incubation in 37ºC. Then the volumes equal to 1.12, 2.24 and 4.4 units per well of protease was separately added to recently formed biofilms in different wells based on the manufacturer protocol and effects of them was studied on reduction of biofilms in 60, 90, 120, 150 and 210 minutes by spectrophotometer. Mean differences between independent groups were compared with Kruskal-Wallis test and SPSS25 software statistical tests and paired means were compared with Mann-Whitney test at 95% significance level.

 Streptococcus mutans was isolated from dental plaque had 98.90% similarity to LPB0225 strain and had intermediated adherence. Reduction of biofilm percentage by Streptococcus mutans LPB0225 was observed in every of units of enzyme and in every periods of times. The most biofilm percentage reduction by Streptococcus mutans LPB0225 was observed in 1.12 units of enzyme in 90 minutes with 97% reduction. Biofilm percentage reduction in 1.12 units of enzyme in 60, 150 and 210 minutes had significantly differences with each other (p value = 0.0008).

 The protease enzyme was able to reduce the dental plaque of Streptococcus mutans LPB0225. The survey on the effect of this enzyme on mixed dental plaques is suggested to control dental caries and plaques created on dentures, and to prevent periodontal diseases caused by dental plaque.

 Due to importance of color determination in the success of cosmetic treatments, we decide to evaluate the prevalence of lateral maxillary incisor color with different systems and compare results with each other, by the hypothesis that there is no difference between the color determination of prosthodontist, dental technician and dental student.

 This cross - sectional study was performed in 2016 on the maxillary lateral teeth of 120 patients came to Kermanshah dental school aged between 20-30 years. The teeth color of each patient was reported by three observers using Vita classic, 3D-master color samples and finally spectrophotometer. Then parameters L, a, b and ΔE were calculated for each patient. Data were analyzed by the use of SPSS 16 with Friedman (α = 0.05) and Wilcoxon (α = 0.017) statistical tests.

 The most common color observed in the Vita classic was A2 (25.83%) and in the 3D-master color sample was 2R2.5 (21.67%). The calculated ΔE of the prosthodontist in Vita classic color samples was less than the other observers (p value < 0.001). In 3D-master, ΔE of dental technician was lower than dental student (p value = 0.016). In other cases, the difference was not significant.

 The most common tooth color in the study population with Vita classic was A2 and with 3D-master was 2R2.5. The accuracy of color determination by prosthodontist in Vita classic was higher than of the technician and the student. In 3D-master, dental technician was more precise than the student.

 Pediatricians are the first group of health care providers who are responsible for medical care of infants. On the other side the prescribed drugs, especially in liquid dosage forms can increasingly cause dental caries. If pediatricians advise preventive methods to parents and refer children to the dentist properly, dental caries will be obviously controlled. The aim of this study was evaluation of knowledge, attitude and practice of pediatricians regarding effect of pediatric medications on oral health of children. 

 This cross-sectional descriptive-analytic study was conducted among 94 pediatricians in Isfahan, Iran, based on a structured questionnaire with closed questions. Data were analyzed using SPSS software version 22 and using one-way ANOVA, t-test, Pearson and Spearman correlation coefficient and Cronbach's alpha coefficient. With confidence intervals of 95%

 Out of total number of samples, 48.9% were female and 51.1% were male. The average age of total sample was 48 ± 10.75 years. The average score of knowledge in the entire sample was 7.9 ± 1.4 based on 0-10, the attitude was 21.8 ± 3.3 based on 0-28 and the practice was 11.6 ± 2.1 based on 0-15. Pearson correlation coefficient showed that there was a direct and relative relationship between the average score of knowledge and attitude (p value < 0.001, r = 0.520).

 Findings from this study revealed a relatively high positive attitude, sufficient knowledge and good practice regarding the effect of pediatric medication on oral health of children among pediatricians.

 Various symptoms have been attributed to tooth eruption. Further, parents use different strategies to reduce or eliminate these symptoms. This study was aimed to evaluate parental information about eruption of primary teeth in Isfahan, Iran. 

 This descriptive, cross-sectional survey was conducted on 100 parents having six-month- to three-year-old children referring to the dental clinics or offices in Isfahan. A questionnaire with validated face and content validity was designed to collect data. It included questions about demographic characteristics, eruption time and the first erupted tooth, symptoms of eruption, and control of symptoms. Data were analyzed by frequency distribution, relative frequency, descriptive indices, and Chi-square test via SPSS 22.     

The most frequent symptoms parents agreed with included high tendency to bite and chew, high saliva flow, and gingival inflammation, respectively. Fever was the most frequent symptom the majority of parents disagreed with. The most frequent methods used by the parents included hugging the child and amusing the child. The most frequent disagreement was reported for the use of sleeping drugs. No significant correlation between parental information about tooth eruption and economic status, parental education, parental age, and number of children was found. The mean score of parental information was 2.37 ± 0.97 and degree of response was 96% (p value < 0.05).   

Parents’ knowledge about tooth eruption was moderate and acceptable awareness on symptoms of tooth eruption and methods of decreasing the symptoms was found.