مجله دانشکده دندان پزشکی اصفهان
سال پانزدهم شماره 2 (پیاپی 67، تابستان 1398)

Dentofacial deformities have been described as changes that affect the jaws and dentition. Such deformities can be found in one jaw or in both jaws. Orthognathic surgery is a process in which dentofacial deformities and malocclusions are corrected with orthodontic and surgical operations of the facial skeleton. The aim of this study was to investigate epidemiological indices and some characteristics related to orthognathic surgery and compare data collected from patients requiring surgery with those from other communities and countries. This cross-sectional study was carried out on patients referring to an oral and maxillofacial surgery center in Isfahan. The subjects had undergone orthognathic surgery in 2011‒2015. Data were analyzed with SPSS 22, with t-test, one-way ANOVA and chi-squared test (α = 0.05). The mean patient age was 25.9 (range, 16‒45 years) with 67.7% (n = 203) and 32.3% (n = 97) female and male subjects, respectively. The most common facial pattern was class III (62%), followed by class II (32.7%) and class I (5.3%). The most common surgery was bimaxillary (57.3%), followed by BSSO (bilateral sagittal split osteotomy, 21.3%), Lefort I (16.3%) and SARPE (5%). Data showed 5.7% of patients had undergone genioplasty. Bimaxillary surgery was more often performed on patients with class III occlusal relationship. Orthognathic surgery was more common among women and young people. Class III deformity was the most common profile among patients seeking surgery in this region.

Odontogenic keratocyst (OKC) or keratocystic odontogenic tumor (KCOT) is a developmental odontogenic cyst which requires special attention due to its unique clinical and histopathological features. CK19 is expressed in non-keratinized normal epithelium and its expression increases during inflammation. Recently the use of this tumor marker has been suggested for identification of odontogenic cysts and tumors. Thus the aim of the present study was to evaluate the expression of CK19 in inflammatory and non-inflammatory keratocyst epithelial cells. This retrospective cross-sectional study was performed immunohistochemically on 25 inflamed and non-inflamed OKC paraffin blocks retrieved from the Archives of the Oral Pathology Laboratories of Isfahan Azad University and Isfahan University of Medical Sciences Medical Faculties. After selecting the samples, sections measuring 3‒5 µm in thickness were prepared. The intensity of cytoplasmic stainability was studied immunohistochemically in three different layers of cyst epithelium: basal, suprabasal and superficial under a light microscope at ×10 and ×40. Data were analyzed with Mann-Whitney test using SPSS 20 (α = 0.05). Expression of CK19 was seen in 100% of inflammatory OKCs and 84% of non-inflammatory OKCs. In inflamed OKCs expression of CK19 was seen in all the three layers of epithelium; however, in non-inflamed OKCs expression of CK19 was seen in the middle layer in only one sample (p value < 0.001). According to the results of the present study, CK19 was expressed in both inflammatory and non-inflammatory OKCs; however, the intensity of staining was different between the groups. In contrast to oral mucosal lesions CK19 was expressed in keratinized odontogenic epithelium. In odontogenic keratocyst, expression of CK19 was seen in response to inflammation as seen in oral lesions.

Temporomandibular joint disorder (TMD) has a significant effect on the sufferer’s social behavior, mental state and oral health-related quality of life. The aim of this study was to evaluate the relationship between TMD and oral health-related quality of life and mental health. In this analytical‒descriptive study, of patients with TMD, who referred to Dental School of Khorasgan University in 2016‒2017, 75 patients with TMD were selected for the case group, while 75 patients with the same conditions but without a TMD diagnosis were selected for the control group. The OHIP14 (Oral Health Impact Profile) questionnaire was used to evaluate each patient’s oral health and GHQ-28 (General Health Questionnaire) was used to evaluate mental health. Chronic pain was graded with RDC/TMD Axis11 (Research Diagnostic Criteria for Temporomandibular Disorders) questionnaire. Data were analyzed with regression analysis, ANOVA and Kruskal-Wallis test, using SPSS 22 (α = 0.05). OHIP14 indicators (prevalence, intensity and popularity) were significantly different between the case and control groups (p value < 0.0001). These scores were higher in female TMD patients compared to males and were higher in patients with high levels of chronic pain. GHQ-28 mental health indicators (materializing, stress, depression and mental issues) were significantly different between the two groups (p value < 0.0001). An increase in pain severity resulted in deterioration of mental health. Analysis of the relationship between mental health (GHQ-28) and oral health (OHIP14) revealed that patients with lower GHQ-28 scores had lower levels of oral health (p value < 0.05). TMD negatively affects oral health-related quality of life and mental health. Mental health and oral health levels are highly correlated in TMD patients; patients with mental health issues often score low in OHRQoL.

Odontogenic cysts and tumors are important jaw lesions. Sometimes their behavior is influenced by non-epithelial factors. Myofibroblasts are specific cells of the stroma. Mast cells affect the differentiation and function of myofibroblasts. Regarding the importance of stroma in the progression of tumors, the present study examined the presence of mast cells and myofibroblasts and their effects on odontogenickeratocyst (OKC), odontogenicmyxoma (OM) and adenomatoidodontogenic tumor (AOT). In this cross-sectional descriptive-analytical study, 10 blocks of OM, 7 blocks of OKC and 6 AOT blocks from the Archives of the Department of Pathology, Isfahan Dental School, were stained with αSMA immunohistochemistry marker and toluidine blue histochemical marker. The mean number of myofibroblasts and mast cells, the color pattern of myofibroblasts and the severity of inflammation of the lesions were evaluated. Data was analyzed by SPSS 20 using Kruskal-Wallis, Mann-Whitney and chi-squared tests (α = 0.05). The degree of myofibroblast staining was not significantly different between the lesions (p value = 0.55), but the severity of inflammation was significantly different (p value = 0.02). The severity of inflammation in OKC was significantly higher than AOT (p value = 0.025) and OM (p value = 0.023) but there was no significant difference between AOT and OM lesions (p value = 0.87). There was a significant difference between the distribution patterns of the lesions (p value = 0.015). The frequency of the focal pattern in the OKC was minimal. The number of intact (p value = 0.72), degranulated (p value = 0.69) and total (p value = 0.75) mast cells were not significantly different between the lesions. There were no significant differences in the number of mast cells and myofibroblasts between the lesions, but myofibrroblasts were expressed with higher levels in OM, which is more invasive.

Over 95% of oral cancers are squamous cell carcinomas (SCC). The prevalence of oral SCC in subjects < 40 years of age has been reported to be 0.4‒3.9% of all the subjects with this lesion. The number of young patients with this malignant tumor has increased in recent years. The present study was undertaken to evaluate the clinico-pathological parameters of OSCC in patients in different age groups, referring to Isfahan Faculty of Dentistry. In this retrospective, cross-sectional study, we reviewed demographic data, clinical features and histopathological parameters of 80 OSCC cases in different age groups from the Archives of the Oral Pathology Department, Isfahan Faculty of Dentistry. The histopathological parameters and malignant tumor grades were evaluated by two oral pathologists. Data were analyzed with SPSS 22, using chi-squared and Mann-Whitney tests (α = 0.05). Of all the cases evaluated, 42 (52.5%) were female and 38 (47.5%) were male, with a female-to-male ratio of 1.1. Alveolar mucosa with 31 (38.8%) cases was the most common site of involvement in all the age groups. The most prevalent clinical feature of OSCC in the patients was exophytic lesion. Well-differentiated (grade 1) OSCC was the most common subtype of OSCC in all the age groups. There was no significant difference in the clinico-pathological parameters between the age groups (p value > 0.05). Based on the results of the present study, there was no specific histopathological parameter between different age groups with OSCC. Despite the increase in the number of young patients with OSCC, it is still considered a specific malignant tumor in old age groups.

Radiography prior to surgery or extraction of the mandibular third molar tooth is clinically useful in treatment planning of surgery. In this study, methodology of radiography prior to surgery was investigated. In this cross-sectional study, an observer randomly visited 20 dental clinics throughout Isfahan. Data, including dentists, patients and type of radiography of mandibular third molars, were collected. Data were analyzed with SPSS 20, using descriptive statistics as well Spearman’s and Pierson’s correlation coefficients (α = 0.05). A total of 200 cases were investigated, with 103 male and 97 female subjects. Of all the cases, 31 cases (15.5%) were without radiography, 6 cases underwent CBCT examinations (3%), 50 cases had panoramic radiographs (25%), 85 cases underwent periapical radiography (42.5%) and 28 cases (14%) underwent periapical-panoramic radiography prior to surgery of third molars. A total of 80 cases (40%) underwent coronectomy and 120 teeth (60%) underwent full tooth removal surgery. There was a significant relationship between the surgical technique and radiography (p value < 0.001). The most commonly used radiographic technique was intraoral periapical radiography. In all cases that underwent CBCT examination, coronectomy was performed and in all the cases with both intraoral periapical radiography and panoramic radiography coronectomy was carried out.

Cephalometric analysis based on estimated natural head Orientation (NHO) could be used as reliable method as registered natural head position(NHP) without related technical problems. This study have been carried out in purpose of preparing a template that makes the use of extracranial reference possible. Cephalograms and photographs from 60 orthodontic patients’ files (30 males and 30 females) with proportionate profile and normal occlusion were analyzed. First, photographs adjusted into natural head position using estimated method then they were transmitted to cephalograms. From landmark N on cephalograms, true vertical and true horizontal lines were drowned. Then hard and soft tissue landmarks were identified and according to coordinate system and mean values, standard facial profile was obtained for male and female separately. The graphic mean face became incorporated into transparent sheets to form template for different gentle and size. SPSS 17 was used for statistic analysis. Difference less than 0.05 was considered significant. The comparison between two gentle registering on landmark N and true vertical line showed that linear measurements on the hole, are larger in males than females. Also in the males, forehead and chin are more prominenced and nasiolabial angle is less than females. use of proportional cephalometric template based on NHO could be an usful diognostic tool that leads to accurate and fast analysis.

Amalgam is one of the most commonly used dental restorative material; however, because of its mercury content, risks of mercury release and its low resistance to corrosion, its clinical use is still a matter of debate among researchers. In this research four different commercially available amalgam products in Iran were studied and their mechanical, microstructural and corrosion resistance were studied and compared. In this study, four different samples of commercially available amalgam (Cinalux, Owzan Company, Iran; Honghai Tech., China; ARDENT Amalgam, Sweden; and SDI [GS-80], Australia) were prepared and mixed with mercury in an amalgamator. Then a hardened sample, measuring 6 mm in diameter and height, from each brand was evaluated by scanning electron microscopy (SEM) for ultrastructural characteristics. In addition, 3 samples from each brand undewent a compressive test in a one-axis compression test device. Resistance to corrosion of 3 samples from each brand was tested by polarization method in saline solution. To exactly compare the quantitative data, one-way ANOVA was performed using Graph Pad Prism 6 software program (α = 0.05). The results showed that although none of the samples had Gama-2 harmful phase, because of differences in the morphology of phases, they exhibited differences in corrosion resistance in the saline solution. Furthermore, their mechanical properties were different due to differences in the morphology of phases and all of them had brittle behavior and their compression strength was >300 MPa. According to the results, the microstructure of amalgam significantly affects its mechanical properties and corrosion resistance. In addition, all the samples evaluated in the present study formed identical phases.

A dentist must be aware about the medications that he/she prescribes, particularly those taken by patients with systemic disorders. The present study focused on the level of knowledge of general dentists in Ardabil concerning the medications prescribed during root canal treatment. The present cross sectional–descriptive study focused on the knowledge possessed by Ardabil general dentists concerning the medications prescribed during root canal treatment in 2016‒2017. To this end, we developed a questionnaire which was completed by as many as 80 general dentists. The questionnaire consisted of questions on demographic data and level of awareness of the dentists. Data were analyzed with SPSS 23, using descriptive statistics and one-way ANOVA (α = 0.05). The results suggested that the level of knowledge on the drugs prescribed during root canal treatment was moderate (14.56 ± 6.91). Furthermore, the results showed that the mean knowledge levels of the dentists concerning the medications prescribed during root canal treatment were significantly different in terms of age, experience and university of origin (p value < 0.05). In contrast, there was no significant difference in terms of gender and source of knowledge acquisition (p value > 0.05). The level of knowledge of the general dentists in Ardabil concerning medications prescribed during root canal treatment was moderate. The inverse relation between the experience and level of knowledge indicates that knowledge of the dentists is not updated relative their increasing experience and no serious measures have been taken to update their knowledge. This reveals the need for consideration of retraining courses for the dentists concerning the medications prescribed during root canal treatment.

Candidiasis is the most common fungal infection in oral cavity, usually caused by Candida albicans. Since one of the most common complications of denture wearing is denture stomatitis, presence of opportunistic microorganisms such as C. albicans and colonization of denture base by these microorganisms, the aim of this study was to compare the effects of three different methods of acrylic resin processing on adherence and colonization of C. albicans. In this experimental study, 60 square acrylic resin samples, measuring 10×10×10 mm3 (Ivoclar Vivadent, Liechtenstein) were processed with three methods of preparation: cold-cured [CC], heat-cured [HC] and injection-molded [IM]. Yeast suspensions were incubated on the surface of resin blocks for 40 minutes and then washed with 1 mL of sterile saline solution; 20 µL of this solution were inoculated on Sabouraud dextrose agar and incubated at 37 C. The colony counts were determined after 24 and 48 hours. At 60- and 120-minute intervals the colony counts were determined again. Data were analyzed with SPSS 20, using two-way ANOVA and paired t-test (α = 0.05). The method of preparation of acrylic resin (p value = 0.001) and duration of proximity of acrylic resin with the yeasts (p value < 0.001) were significant. The lowest colony counts were observed in the cold-cured method. In all these three methods and durations of proximity of acrylic resin and C. albicans, the colony counts at 48 hours were significantly higher than those at 24 hours (p value < 0.001). The acrylic resin preparation method affected the adhesion and colonization of C. albicans. Considering the lower colonization in cold-cured acrylic resin, it is the most appropriate acrylic resin, especially for those with poor oral hygiene or those susceptible to fungal infections.

The most favorable orthodontic treatment outcomes are obtained when the treatment starts at the most appropriate stage of growth. In such a case, it will have the least potential complications and the best therapeutic stability. Many researchers have shown that chronological age is not a reliable method for evaluation of skeletal development. It is very important to use a reliable index to identify different stages of skeletal maturation. The aim of this study was to examine the relationship between maturation of cervical vertebrae and calcification of teeth in children 9-14 years of age. In this cross-sectional study, cephalometric and panoramic radiographs of 200 patients were used. The patents were aged 9‒14 years and had referred to the Department of Orthodontics of Isfahan Dental School and specialty clinics. In this study, to determine the calcification of canines, first premolars, second premolars and second molars, Demirjian et al technique was used; in addition, Baccetti et al technique was used to evaluate the different stages of skeletal maturation. Data was analyzed using SPSS 23 and Spearman’s correlation coefficient (α = 0.05). The results of this study showed a significant correlation between the calcification of canines, first and second premolars, and the second molars on both the left and right sides with different stages of cervical maturation. Spearman’s correlation coefficient for different teeth were as follows: canines, r = 0.5; first premolars, r = 0.5; second premolars, r = 0.6; and second molars, r = 0.6; p value < 0.001). However, in boys the relationship was significant only in the left molar teeth (r = 0.3), right molar teeth (r = 0.26) and left canine teeth (r = 0.3), (p value < 0.001). The correlation between calcification of teeth and cervical vertebrae in girls was significant; in boys it was significant only in second molar teeth and left canine teeth.

One of the most important steps in root canal treatment is to determine the exact working length as an effective factor in the success of treatment. Various tools and methods have been introduced to determine the working length, including electronic apex locators. This study was undertaken to compare the accuracy of three electronic apex locators, Root ZX, Woodpecker and Coxo in determining the actual working length. In this in vitro study, 30 maxillary central incisors meeting the inclusion criteria were selected and the working length of each tooth was determined by three electronic apex locators: Root ZX, Woodpecker and Coxo. After irrigating the root canals with 6% hypochlorite and 0.9% normal saline solutions, electronic measurements were performed using a #15 K-file in the range of 1±0.5 mm at the apical constriction according to the manufacturer's instructions. After abrading 4 mm of the root end, the actual working length was calculated under a microscope from the distance between the coronal reference point and the apical constriction. Data were analyzed with chi-squared test and Fisher’s exact test, using SPSS 16 (α = 0.05). The accuracy rates of Root ZX, Woodpecker and Coxo apex locators were 76.7% and 100%, 90% and 100%, and 93.3% and 100% in the range of 1 ± 0.5 mm, respectively. No significant differences were found between the working lengths measured by three apex locators and the actual working lengths. According to the results of this study, none of the three apex locators exhibited accuracy of 100% exactly at the apical constriction. There were no statistically significant differences between the working lengths obtained by three apex locators and the actual working lengths.