Comparison of tooth size discrepancy in Cl two malocclusion patients with normal occlusions

Statement of Problem: There must be a proper mesiodistal tooth size ratio [Bolton analysis] between maxillary and mandibular teeth for good occlusal interdigitation. Therefore the Bolton analysis should be considered during diagnosis, treatment planning and predication of ultimate results

Purpose: The purpose of this study was to appraise tooth size ratios in Cl II malocclusion group and compare them with normal individuals

Materials and Method: This study was carried out on 60 pre-treatment orthodontic casts of class II malocclusion patients and 60 diagnostic casts of normal occlusion individuals which were selected through cluster sampling in accordance with the selective criteria. Each group consisted of 30 men and 30 women. The greatest mesiodistal diameters of all the teeth on each cast were measured by a digital caliper with 0.01mm accuracy except the second and third molars. Then tooth size ratios were analyzed as Bolton described. The statistical analysis were performed by chisquare and t-tests using SPSS

Results: The prevalence of anterior and overall tooth size discrepancy was relatively high [28.3%, 20%], showing no significant difference between men and women [p> 0.05]. The mean of anterior and overall tooth- size ratios in Cl II malocclusion group were 79.18 and 92.39 respectively, which were statistically different from the Bolton study [ideal occlusion] ratios [p< 0.05].There were no statistical difference between the means of anterior and overall ratios of men and women, neither in Cl II malocclusion group nor in the normal individual group [p> 0.05]

Conclusion: Considering the high frequency of tooth size discrepancy among CLII patients and the significant difference in Bolton ratios between this malocclusion and ideal occlusions; it seems that tooth size discrepancy can be considered as a possible etiologic factor and Bolton analysis should be performed as a pre-treatment diagnostic tool for this type of malocclusion

Correlation between dental and chronological age in 6-15 years old orthodontic patients in Qazvin

The use of different stages of tooth eruption is preferred to estimate the children chronological age as it is less affected by hormonal changes or nutritional status. The most accurate method developed for determination of dental age is the Demirjian technique as indicated by different studies. The objective of this study was to assess the correlation between dental age and chronological age in 6-15 years old orthodontic patients in Qazvin in 2010. In this descriptive analytic study, 468 individuals [255 females and 213 males] were selected based on simple sampling and the dental age for each person was determined by Demirjian technique based on 7 mandibular left teeth. The chronological age was calculated by subtracting the birth date from the panoramic date. The correlation between the dental age and chronological age was assessed by Pearson coefficient and the difference between two genders evaluated. Significant and direct correlation was found between the chronological age and dental age [r=0.912 for females and r=0.905 for males]. With the exception of age 12 in males, the dental age of each individual was higher than the chronological age. The highest and the lowest differences between the two dental age and chronological age in each gender was noted in chronological ages of 6 and 14 in males and 6 and 8 in females, respectively. Based on results found in the presents study, it seems that the Demirjian technique to be valid for dental age estimation among Iranian people. However, the development of exclusive tables for Iranian population is necessary due to the overestimation of the individual's dental age compared to the chronological age

[ study on efficacy of NSAIDS in controlling pain caused by orthodontic treatment]

Considering the pain as one of the most significant reasons for patients avoiding orthodontic treatments, the topic of pain control appears to be of prime importance for both clinicians and patients. This study was aimed at determining the efficacy of commonly used non-steroidal anti- inflammatory drugs [NSAIDs] in controlling pain following orthodontic procedures. This was a double-blind clinical trial performed on a total of 75 patients, randomly divided into 5 groups following the placement of their initial arch wires. The members of each group received one of the 5 different treatments [Ibuprofen 400 mg, Naproxen 250 mg, Mefenamic acid 250 mg, Aspirin 325mg, and starch as placebo]. After receiving 2 doses of drugs [one hour before and six hours after bonding] the patients indicated the severity of their pain on a 100mm horizontal line [VAS] during mastication, biting, fitting on anterior and posterior teeth in different specified times. Statistical analyses were carried out based on ANOVA and t-test. The pain increased soon after the placement of the arch wire and reached its peak in 24 hours. In all cases, the least pain was reported following the administration of Ibuprofen and the most after taking placebo. Although all NSAIDs were more or less effective in controlling pain, ibuprofen was found to be relatively of higher efficacy in decreasing the pain

use of orthodontic need index [IOTN] in a referred Iranian population

IOTN index has been used in different countries for assessment of orthodontic treatment needs in recent years. This index has two components, an aesthetic component [AC] and a dental health component [DHC]. The aim of this study was assessment of orthodontic needs on the basis of IOTN index in those people who had come for orthodontic treatment. We used IOTN index in order to assess the orthodontic treatment needs of 343 applicants [262 females and 81 males] with a mean age of 18.1 [standard deviation 3.8 years]. Who had come for treatment during a certain period of time [8 months] For determining the AC we used a set of 10 pictures graded on the basis of aesthetical features of teeth. The DHC Component of Index that has five degrees was determined bases on study casts with standard preparation. If necessary and for more accuracy panoramic radiographies of patients were also used. The analysis of the obtained data was performed using Kappa, Chi-square and Spearman's tests. The results with determination of subjective needs on the basis of AC by patient's perceived need indicate a lock of significant relation between gender and the patients' perceived need for AC [p<0.05]. Most of these patients had determined their AC to be between grades 1-4, the results of AC determination through normative need assessment were the same as the results of perceived need Assessment. Which in case of DHC determination it was revealed that most subjects had a grade between 4 and 5, and there was a significant relation between DHC and type of malocclusion [p>0.05]. Subjective data of IOTN index alone can not be considered an appropriate indicator of orthodontic treatment needs determination

prevalence of Anterior Open Bite and the associated dentoskeletal malformations in 9-14 year-old students of Qazvin

Anterior Open Bite [AOB] is one of the most severe orthodontic diseases to treat and often with poor prognosis. However, an early diagnosis accompanied with proper evaluation of etiological factors may lead to a shorter therapeutic period and also a better prognosis. To determine the prevalence of AOB and the associated clinical and cephalometerical changes in 9-14-year-old students of Qazvin. 1461 students [males: 701, female: 760] were evaluated and AOB was found in 56 students [32 boys and 24 girls]. Thirty students out of 56 were referred to the School of Dentistry for a lateral cephalometric radiography. Thirty lateral cephalogram x-rays were also taken from students with normal occlusion as control group. The prevalence of AOB in 9-14-year-old students in Qazvin was 3.83% which was significantly higher in girls than boys. From a cephalometric point of view, the articular, gonial, sum of post, SN-MP and basal angles significantly increased but UAF/LAFH and UAFH were decreased. Patients with Anterior Open Bite showed a downward backward lower jaw rotation with a growth pattern in their faces more vertical than horizontal. The posterior upper teeth in patients were also over-erupted which must be considered in treatment plan