Journal of Dentistry, Shiraz University of Medical Sciences
Volume:20 Issue: 1, Mar 2019

Palatal rugae have been considered equivalent to fingerprints, as they are unique to each individual. It has been shown that palatal rugae are associated with specific racial groups and are known to aid sex identification. Due to the lack of any published data on palatal rugae morphology on Iranian children, the present study was performed. The present study aimed to investigate differences in the morphology of individual palatal in a sample of Iranian children. Additionally, it is intended to develop discriminant function to identify sex, based on rugae morphology. A total of 120 pre-orthodontic casts were evaluated for different rugae patterns using the Thomas and Kotze classification. The casts were equally distributed between sexes with an age range of 6-12 years. Rugae length, shape, and associated morphology were recorded and the independent t test and Chi-square test were used to compare the mean and relationship between the attributes. The discriminant function analysis was applied to the data in order to determine the applicability of palatal rugae patterns as an aid for sex identification. While the total rugae count showed an insignificant difference between the males and females, the rugae count on the right side of the palates showed a significant difference (p= 0.046). The primary rugae were most common in both sexes, followed by the secondary and fragmentary rugae. The most prevalent rugae shape between both sexes was the wavy rugae followed by the curve and straight shapes in males and the straight and curve shapes in females. A significant difference was observed in the number of the curve rugae between the sexes. Discriminant function analysis allowed sex differentiation with an accuracy of 60.8%. Palatal rugae shapes are unique to each individual and could be used as a potential tool for sex identification. Further research on a larger sample is required to fully confirm the application of this method (e.g. in forensic medicine) as a complementary technique for sex identification.

 Considering the clinical differences between central giant cell granulomas (CGCGs) and peripheral giant cell granulomas (CGCGs) despite their same microscopic feature and possible role of angiogenesis in this issue, The aim of the present study was to compare microvessel density (MVD) between CGCGs and PGCGs of the oral cavity using CD31 and CD34. Immunohistochemical staining was performed on 18 PGCGs and 19 CGCGs using a monoclonal antibody against CD34 and CD31. MVD was assessed and compared between the lesions using T-test for statistical analysis. p< 0.05 was considered significant. The expression levels of both CD34 and CD31 were significantly higher in CGCGs compared to PGCGs (p< 0.002 and p< 0.001, respectively). Significant differences in MVD assessed by both markers were observed between males and females in PGCGs (p< 0.05), but not CGCGs (p< 0.2). The combined evaluation of old- and newly-formed vessels by pan-endothelial cell markers showed differences between CGCGs and PGCGs, supporting the possible vascular-proliferative nature of the former. Whether this difference has a part in their diverse biologic behaviors and the role which pre-existent vessels play in comparison to neo-formed vasculature, requires further investigation.

As an important determinant of social acceptability, facial attractiveness can be influenced by decisions of orthodontists through treatment. The purpose of this study was to determine the difference in perception of facial attractiveness among male and female raters in different age groups through comparison of silhouettes. 208 subjects (99 male, 109 female) aged between 18 to 70 years were assigned to three groups of young adults, middle-aged and senior and rated pre-designed silhouettes on a 7-level rating scale (1= the least esthetic, 7=the most esthetic). Two series of 7 silhouettes were prepared for men and women in which the mandible was protruded or retruded in 2-mm increments from the average. The evaluators were asked to grade the profiles separately for male and female. T-test and one-way ANOVA were used for the statistical analysis with α = 0.05. The first and third age groups, favored female profile 2 among class II profiles. However, the second age group preferred the average profile. Male class II profiles were rated exactly as female ones among the three age groups. The average female class III silhouette was preferred in all age groups. The first and second age group preferred the average male profile in male class III silhouettes. The oldest group however, preferred profile 2. For both sexes, the least acceptable profile in each set of silhouettes was the most protruded or retruded. There were few differences in perception of facial attractiveness between different age groups. In all groups, even small mandibular protrusion was unacceptable and mild retrusion was considered attractive.

 To perform a successful endodontic treatment, sufficient knowledge about the number of root canals and their morphology is essential. Missed normal variations may burden this treatment. This study aimed to evaluate the presence of the second canal in the roots of mandibular central and lateral incisors in an Iranian population by employing CBCT images. This cross-sectional study recruited 180 CBCT image of mandible to evaluate the number of roots as well as the number and types of root canals. Data for each sample were collected in a data collection form set and analyzed by chi-square test using SPSS17 software. A total of 681 permanent mandibular incisors were assessed. All samples had one root. Most of the samples (70.3%) had only one canal (type 1 Vertucci classification). The frequency of dual-canal in samples was 29.7%; the prevalence of dual-canal in mandibular lateral teeth (35%) was more than the mandibular central teeth (23.9%, p< 0.05). Following type 1 canal, type 3 (15.7%), type 5 (12.9%), type 4 (0.7%), and type 2 (0.3%) canals had the highest frequencies respectively. Based on this study, presence of a second canal in mandibular lateral teeth (35%) is more common than in mandibular central teeth (23.9 %). The most common canal type observed was type 1 (according to Vertucci classification) followed by type 3.

 Laser can influence bonding mechanism by increasing the penetration depth of adhesive in smear layer. The effect of 940 nm diode laser on microtensile bond strength of adhesive to dentin has not been investigated in previous studies. The aim of this study was to evaluate the effect of 940 nm diode laser irradiation on microtensile bond strength of Single Bond 2 to dentin. Thirty sound premolars extracted for orthodontic reasons were randomly divided into five groups as follows: G1 or control: etching+ Single Bond2 (SB); G2: diode laser (940 nm wavelength, 1W power, continuous mode)+ etching+ SB; G3: etching+ laser irradiation+ SB; G4: etching+ SB+ laser irradiation+ adhesive curing; G5: etching+ laser irradiation+ SB +laser irradiation +adhesive curing. After the bonding procedure, Z250 composite resin was applied on the dentin surface in three layers of 2 mm thickness. After 24 hours of immersion in distilled water at 37°C and thermocycling for 1000 thermal cycles, the teeth were sectioned into 1mm2 sticks. The microtensile bond strength was measured using a universal testing machine. Bond strength (MPs) was analyzed by one-way ANOVA followed by HSD post hoc Tukey’s test (α=0.05). G4 (38.35±8.99) showed the significant highest bond strength compared to other groups (p= 0.000). G5 (25.16±6.14)showed significantly higher bondstrength than the control group (18.85±4.79)(p= 0.032).Bond strength of G2 (23.39±6.07)and G3 (22.85±5.11)groups was the same and similar to that in the control group (p> 0.05). Based on the results of this study, it may be concluded that dentin surface irradiation with 940 nm diode laser after adhesive application and prior to curing can significantly increase the bond strength of composite to dentin.

 Sealing ability is one of the most important factors for successful endodontic treatment. Some studies have shown that the powder to liquid ratio can influence the properties of dental materials. Subsequently, this may happen for those used for sealing in endodontics. The purpose of this research was to assess the microleakage of calcium-enriched mixture cement (CEM cement) apical plug in different powder to liquid ratio. Ninety-six extracted human single root and single canal teeth were decoronated. Working length was determined using ≠15 k-file. Canal preparation was performed using step back method. Samples were divided into 3 groups randomly. CEM cement was placed into the canal with 1.13, 2.27 and 3.40 powder to liquid ratio in the group 1, 2 and 3, respectively. After complete setting of CEM cement, the micro leakage value was evaluated using fluid filtration method. Data were analyzed using ANOVA and Scheffe tests. The bubble movement in three groups showed a statistically significant difference (p< 0.001). Minimum and maximum bubble movements were observed in the group with powder to liquid ratios of 3.40 and 1.13 respectively. Increased CEM Cement powder to liquid ratio will increase the sealing ability of this material as apical plug. Considering the conditions of this study, the powder to liquid ratio of 3:40 provided the best sealing ability.

 Burning sensation in Hashimoto patient’s oral cavity is an unknown prevalent problem. This study aimed to evaluate the prevalence and intensity of burning mouth syndrome (BMS) in patients suffering from Hashimoto’s thyroiditis in all public hospitals in Shiraz, 2016. A total of 153 patients with Hashimoto’s thyroiditis were selected based on simple random sampling. The initial level of thyroid stimulating hormone (TSH), Anti-TPO (thyroperoxidase), Anti-TG (thyroglobulin), Free T3 (triiodothyronine) and Free T4 (thyroxine) serum as the indices of Hashimoto’s thyroiditis was assessed. The BMS intensity was measured according to each patient's verbal or nonverbal expression about the pain experience based on visual analog scale (VAS). Based on the clinical evaluation and interview, only 19out of 153 cases (12%) reported BMS. The mean BMS was 3 based on VAS. Statistically significant association was detected between the level of TSH (p= 0.0001), Anti-TPO (p= 0.035), Anti-TG (p= 0.0001), Free T3 (p= 0.0001), Free T4 (p= 0.0001) indices in patients with BMS. Significant association was also observed between the level of Anti-TPO (p= 0.0001), Anti-TG (p= 0.0001), Free T3 (p= 0.0001) and TSH (p= 0.0001) indices and BMS intensity. However, no significant association was found between the BMS severity and Free T4 (p= 0.056). The level of TSH, Anti-TPO, and Anti-TG, Free T3, and TSH indices of Hashimoto’s patients were associated with the presence and severity of BSM. However, Free T4 level was only associated with the presence of BMS and not the intensity.

 The removal of a third molar tooth associated with a pathological condition is usually an easy decision. However, it is necessary for clinicians to know about the prevalence of preoperative pathologies associated with impacted mandibular third molars to the identification of the prophylactic approach to be applied to symptom-free impacted third molars. The objective was to investigate the effect of the angulation of impacted mandibular third molars on the prevalence of associated pathologies. In this retrospective study, we examined the panoramic radiographs of 954 patients referred for impacted third molar surgery. A total of 1598 impacted mandibular third molar teeth were included in the study. Pathological conditions included the caries on distal surface of the adjacent second molar, caries on impacted mandibular third molars, bone loss distal to the adjacent second molar, the radiolucent area distal to the impacted mandibular third molar were determined. Caries were observed more in the impacted third molar (18.9%) compared to the adjacent second molar (15.8%). The radiolucent area on distal surface of the impacted mandibular molar was 11%, while the periodontal bone loss distal to the adjacent second molar was 4.9%. Mesioangular-impacted mandibular third molars had high risk of caries development on second and third molar. The prevalence of periodontal tissue damage to the adjacent second molar was higher in horizontal and mesioangular angulation. Vertical and distoangular-impacted mandibular third molars had high risk for bone loss at distal aspect. The prevalence rate of pathological conditions in mesioangular impacted teeth was higher.

 In dental profession, exposure to risk factors of musculoskeletal disorders raises the probability of musculoskeletal injuries in different parts of the body. This study aimed to determine the prevalence of musculoskeletal disorders (MSDs), assess the risk of MSDs, and determine the risk factors of musculoskeletal injuries among dentists of Shiraz city. In this cross-sectional study, 136 dentists of Shiraz city were randomly selected. The data were collected by Nordic musculoskeletal questionnaire (NMQ). Ergonomic assessment of exposure to MSDs risk factors was carried out by assessment of repetitive tasks (ART) technique. In order to assess dentists’ exposure to MSDS risk factors, the method of ART (ART) was adopted. This method has been designed to assess the risk of those tasks, which require repetitive motion of upper limb, especially hands and arms. The collected data were analyzed through SPSS Software (version. 22). The study regarded p value of <0.05 as significance level. Mean age of the participants was 35.6±8.7 years. The 12-month prevalence of MSDs among dentists was 91.9%. The results suggested that risk of MSDs among dentists was high. The results of logistic regression analyses indicated that female gender (p< 0.001) and exercise for less than 3 hours per week (p= 0.001) played significant roles in occurrence of MSDs among the study population. Additionally, the results of ART assessment revealed that risk of MSDs in the right side of the subjects’ bodies was higher. The findings showed that risk of MSDs and their prevalence in the study population was high with significant association. Based on the results of regression modeling, it seems necessary to pay proper attention to factors associated with MSDs to develop ergonomic solutions to reduce or eliminate musculoskeletal injuries.

 It is expected that the prevalence of caries would be more in diabetics than in non-diabetic individuals due to the complications subsequent to metabolic changes such as xerostomia and increased glucose level in saliva. On the other hand, the restriction of glucose consumption in the diabetics’ diet would be a reason to justify decreasing dental caries in them. The aim of this study was to compare the mean DMF (decayed, missed due to decay, and filled teeth) index in type I diabetic and healthy children. The DMF index was assessed in 100 type I diabetic children (9-14 years-old, mean= 12±1.23) and compared with the DMF index in 100 age- and sex-matched metabolically healthy controls. Data were collected through a questionnaire and clinical examinations and analyzed statistically by t-test and one-way ANOVA. The results showed that there were no significant differences between the mean DMF index of diabetic children and healthy children. The mean DMF was significantly lower in those who regularly used a toothbrush and dental floss than in those who did not use in both groups (p< 0.05). Diabetes did not affect dental condition by itself but adequate oral hygiene had an important role in controlling caries and promoting oral status.

Tapia’s syndrome is an infrequent complication of airway manipulation. It is usually due to an extra-cranial ipsilateral injury to the hypoglossal nerve and the recurrent laryngeal branch of the vagal nerve, which can happen after any surgery. It is usually characterized by unilateral paralysis of the muscle of the tongue and vocal cords although it can also occur bilaterally. We present a patient with postoperative unilateral hypoglossal and recurrent laryngeal nerves palsy that occurred after cosmetic malar augmentation for esthetic correction of the left cheek flatness with an uncomplicated transnasal intubation. We report the first case of Tapia’s syndrome after porous polyethylene implantation for cosmetic cheek reconstruction. The patient was treated immediately after the diagnosis with 0.5mg dexamethasone for two weeks. After three months, the movements of the vocal cord and tongue movement started to improve and the patient’s hoarseness fully recovered after six months.

Epitheloid hemangioendothelioma (EHE) is a rare vascular neoplasm of intermediate malignant potential. EHE commonly involves lungs, liver soft tissue, and bone. EHE is extremely rare in tongue and up to our best knowledge only nine cases of EHE of tongue reported in the literature. Clinically EHE usually presents as an asymptomatic mass. Microscopically, EHE exhibits proliferation of epitheloid cells and spindle shaped endothelial cells. Epitheloid cells show cytoplasmic vacuoles with few cells containing RBCs. A 34-year-old male presented to our institution with the chief complain of swelling on the base of the tongue from eight months. Surgical excision was done. An extensive work up of immunohistochemistry was done using different markers including CD 31, CD 34, Ki 67, Factor VIII, and BCL2. Correlation of histopathology and immunohistochemistry confirmed the diagnosis of EHE. The follow up period of 2 years was uneventful.