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Introduction. We aimed (1) to measure the mesiodistal and buccolingual widths of the permanent dentition in Iranian orthodontic patients, (2) to determine cut-off points for sex identification based on the mesiodistal and buccolingual diameters, and (3) to calculate Bolton indices. Methods. The mesiodistal and buccolingual dimensions of 28 maxillary and mandibular permanent teeth in 331 Iranian nonsyndromic orthodontic patients (dental casts and radiographs) aged 12 to 35 years old with fully erupted permanent dentitions (except the third molars and some sporadic cases of a few teeth missing or excluded) were measured. The anterior, posterior, and overall Bolton ratios were calculated in cases with no missing teeth in the 6-to-6 range. Potentially associated factors (the skeletal Angle classes, crowding, sex, jaws, sides, and age), as well as the value of these measurements for sex determination and cut-off points for sex identification based on these measurements were assessed using receiver-operator characteristic (ROC) curves, analysis of variance (ANOVA), Tukey, unpairedt-test, partial and Pearson correlation coefficients, and multiple linear regression (α=0.05). Results. Sex dimorphism was very frequent (P≤0.05in 41 out of 56 measurements). Only the buccolingual widths of the maxillary lateral and the mandibular central and lateral differed across the Angle classes (ANOVA/Tukey,P<0.05). Cut-off points were estimated for 38 dental measurements, which were proper for sex identification (P<0.05), with 8 (2 maxillary and 6 mandibular) measurements being highly appropriate (having areas underROC curves≥64%,P<0.05). Both the mandibular canines were the only teeth with all four measurements highly appropriate for this purpose. Controlling for the role of sex, aging was associated negatively with several crown dimensions (the buccolingual widths of the maxillary first and second premolar and mandibular second premolar and first molar; the mesiodistal diameters of the maxillary central, canine, first premolar, and first molar, mandibular central, lateral, first premolar, and first molar,P≤0.05, partial correlation coefficient). There were significant correlations among crown sizes. All the 28 (right/left-averaged) measurements were smaller in microdontia cases (P≤0.002). The anterior, posterior, and overall Bolton indices were 78.05, 105.42, and 91.87, respectively. There were correlations between the overall Bolton ratio with the other two Bolton ratios (PearsonR=0.696,R=0.740,P<0.0005) but not between the anterior and posterior Bolton ratios (R=0.045,P=0.459). The skeletal Angle classes might not be associated with the overall and anterior Bolton ratios (ANOVA, regression, Pearson,P>0.05). However, the posterior Bolton ratio was smaller in class II cases compared to classes I or III (Tukey,P≤0.045). In the whole sample, there was no sex dimorphism in Bolton ratios (t-test,P>0.05). However, in Angle class II patients, the anterior Bolton ratio was greater in men than in women (P=0.014). Conclusions. Sex dimorphism might be very common in the dentition of Iranians, with aging significantly reducing some measurements. The buccolingual widths of some incisors might differ across the skeletal Angle classes. Mandibular canines are the most appropriate teeth for sex identification. The Angle classes might not be associated with the anterior and overall Bolton ratios; nevertheless, the posterior Bolton ratio might be smaller in class II cases compared to others. In general, sex might not affect Bolton ratios; however, in class II patients, the anterior Bolton ratios might be larger in men.

Introduction: The Size and shape of the teeth are genetic characteristics. Anomaly in tooth size and shape is due to disturbances in a sequence of morph differentiation and his to differentiation in tooth bud formation periods and is more common in permanent dentition than deciduous teeth. The most common tooth size discrepancy is in the upper lateral incisor and upper and lowers 2nd premolar teeth. About 5% of malocclusions are due to tooth size discrepancy. For having the best occlusion, we must have the appropriate size and shape of teeth. As there is a relation between deciduous and permanent teeth, proper evaluation and timely intervention are essential for achieving a good occlusion in anterior and posterior segments of permanent teeth. Thus we need interceptive orthodontic in mixed dentition period with a good treatment plan for removing the malformed tooth at the proper time and appliance therapy for eruption guidance of other teeth. Case Report: A rare tooth anomaly (double teeth) in deciduous teeth: The case reported here is a 9- years old boy with a delayed eruption of the right lower permanent lateral incisor and gemination of lower right deciduous canine and crowded upper incisors that refer to the orthodontic department of dental school of Ahvaz Jundishapur University of Medical Sciences on7th October of 2020. Conclusion: After creating patient’s file, the further steps of molding from the patient and gathering all diagnostic records such as panoramic radiography, intraoral photography was carried out and ordered to remove the malformed baby tooth afterward. In the next stage, on the patient's treatment, we installed a strap onto the patient's first permanent molars, remolded them, then created a lingual arch to maintain the vegetative space in the lower permanent canine and prevent its collapse, and increased the patient's overbite. Keywords: Tooth, Deciduous, Dental occlusion.

Backgrounds: Quality of life related to oral health impact profile-14 (OHIP-14) is one of the important dimensions of quality of life. Since using narcotics or stimulants increases the incidence of periodontal diseases, we aimed to determine impact of Oral health-related quality of life in narcotic or stimulant addicts who referred to maintenance methadone therapy (MMT) centers in Ahvaz City, Iran.Methods: It was descriptive-analytical cross-sectional study which has conducted on 187 narcotic and stimulant addicts who referred to MMT centers in Ahvaz city; 2020. The data collection tools included the demographic variables and the standard OHIP-14 questionnaires. Descriptive statistics, independent t-test, one-way analysis of variance, and LMS test were run at the significance level of less than 0.05. Results: The mean and standard deviation of the participants' age was 36.03 ± 8.98 years. The quality-of-life scores related to oral health were 34.89 ± 6.50 totally as well as 37.37 and 33.96 in narcotic and stimulant addicts, respectively. The total quality of life related to OHIP-14 did not have a significant relationship with variables of age, life companions, level of education, number of children, economic status, employment status, insurance status, underlying disease, toothbrush use status, last dentist visit, and number of missing teeth (P> 0.05). However, a significant difference was found between the quality of life related to oral health based on the type of substance used (narcotic or stimulant), so that the mean quality of life related to oral health was higher in narcotic addicts than stimulant users (P Conclusion: The quality of life related to OHIP-14 was more unfavorable in stimulant users than narcotic users. So, policy makers and authorities are required to focus their interventions and research programs to improve health-related quality of life in addicts, especially stimulant users.

Summary Objective Initial stability of miniscrews is an important factor in their success as orthodontic anchorages. One of the factors affecting this stability is the stresses exerted to the bone by the screw. Since the distribution and extent of stresses and strains produced during insertion or removal of miniscrews had not been measured before, this study used finite element analysis (FEA) to measure these parameters in tapered versus cylindrical screws with or without pilot sockets. Materials and methods An FEA model of maxilla, pilot hole, and tapered/cylindrical miniscrews were created from 875 CT scan data. The bone cortex was considered 2 mm thick. The cancellous bone was reconstructed below the cortical bone. Miniscrews were modelled on the basis of commercial titanium tapered and cylindrical miniscrews (1.6 mm wide, 8 mm long). The diameter and length of the guiding hole were considered to be 1.1 and 1.5 mm, respectively. The miniscrews were inserted (and removed) between the maxillary second premolar and first molar. Stress/strain produced in the bones or screws were measured. Results During screw insertion, in all setups, the highest stress existed within both the bone and screw, when the screw was in the cortical bone; after insertion into the cancellous bone, the stress suddenly dropped. In cylindrical screws, the highest amount of stress was distributed around the neck which was used for screw driving. In tapered screws, the stress was mostly distributed around the front one-third of the screw. During screw removal, the results of four setups were rather similar with stresses concentrated around screw necks, in the depth of the screw hole, and around the bone surface. The greatest bone stress during insertion was caused by the pilot-less tapered screw (10.18 MPa) and the lowest stress was exerted by a pilot-less cylindrical screw (0.74 MPa). Conclusion Most of the stress and strain is tolerated by the cortical bone and not the cancellous one. Using cylindrical miniscrews might be more bone-friendly. However, all cases had stresses below tolerable thresholds, and hence are safe.

This study established about 50 anteroposterior and vertical cephalometric norms of five tracing analyses in Iranians, using a large sample.Lateral cephalographs of 130 subjects (85 females, 45 males, with an average age of 22.77 ± 2.55 years (range 20-29)) were traced manually using the Ricketts, Holdaway, Z-Merrifield, Epker, and Legan-Burstone soft tissue analyses. The role of age and sex on measurements, as well as the comparisons between Iranian norms with Caucasians from European decent, was determined statistically (α = 0.001).Age had no significant effect (all P values 0.01). Sexual dimorphism existed in terms of numerous parameters. Compared to analysis standards, upper lip to E-plane, nose prominence, upper lip thickness, nasomental angle, Z angle, interlabial distance, subnasale perp to chin, subnasale-stomion:stomion-menton, subnasale-lower lip:lower lip-menton, interlabial gap, and vertical lip-chin ratio were smaller in Iranians. Superior sulcus depth, skeletal profile convexity, upper lip strain, upper lip curvature, H-angle, soft tissue chin thickness, nasofacial angle, subnasale perp to upper lip, subnasale perp to lower lip, maxillary prognathism, lower face throat angle, upper lip protrusion, lower lip protrusion, mentolabial sulcus, and lower vertical height-depth ratio were greater in Iranians compared to the norm (P ≤ 0.001).A great degree of sex dimorphism might exist among Iranians. Many textbook norms might not be the best options for diagnosis or treatment of Iranians.

Introduction Factors affecting the attractiveness of soft-tissue profile have been assessed in only a few studies, with limited methodologies (such as few variables, small sample sizes) and bivariable analyses. Therefore, this study was conducted to elucidate esthetic factors of profile silhouettes among a long list of cephalometric variables with the use of multivariable analyses for the first time. Methods Profile silhouettes of 70 Iranians (35 men and 35 women) with Class I/good occlusions and balanced faces were rated twice by 10 Iranian laypersons, and were given overall profile beauty scores (from 10 to 50). After careful landmark identification by 3 orthodontists, unrepeated cephalometric measurements (from Holdaway, Ricketts, Z-Merrifield, Epker, and Legan-Burstone analyses) were traced twice on all cephalographs. The effects of these variables (plus sex and age) on profile beauty scores were assessed with the use of Pearson coefficient and multiple linear regression. Cephalometric characteristics of Persian attractive profiles (scores from 40 to 50) were compared with Caucasian orthodontic norms (α = 0.05). Results The following variables were significant in the best models: soft-tissue facial angle (β = −0.348, P = 0.016), nose prominence (β = −0.245; P = 0.044), skeletal profile convexity (β = 0.255; P = 0.052), upper lip curvature (β = 0.405; P = 0.042), nasolabial angle (β = 0.546; P = 0.000), nasofacial angle (β = 0.259; P = 0.028), Z-angle (β = 0.557; P = 0.015), H-angle (β = −0.360; P = 0.013), upper lip to E-plane (β = 0.691; P = 0.001), lower lip to E-plane (β = −0.674; P = 0.002), Sn–lower lip (β = 0.338; P = 0.055), lower lip–menton (β = −0.299; P = 0.025), Sn FH-perp to upper lip (β = −0.425; P = 0.001), Sn-Stms:Stms-Me′ (β = −0.372; P = 0.016), facial convexity angle (β = 0.710; P = 0.000), lower lip protrusion (β = −0.342; P = 0.005), and interlabial gap (β = −0.179; P = 0.050). Sex and age were not associated with profile attractiveness (P > 0.75). Conclusions More convex skeletal and soft-tissue profiles, less prominent noses with higher tips, subnasales anterior to the upper lip, more protruded upper lips, less prominent lower lips, smaller interlabial gaps, and more protruding chins might improve profile esthetics.