Journal of Mashhad Dental School
Year:2008 | Volume:32 | Issue:2 (65)|Papers Count:13

Introduction: It is necessary to evaluate skeletal maturation in functional orthodontic treatments. The most common method for determining skeletal maturation is made upon assessing hand-wrist radiographs. Recently, different methods use cervical vertebrae on lateral cephalogram to determine skeletal maturation. The aim of this study was to evaluate the correlation between different methods of assessing skeletal maturation using cervical vertebrae and to c ompare those with hand-wrist radiograph.Materials & Methods: In this descriptive-analytical study, hand-wrist radiographs and lateral cephalograms in NHP were obtained from for 47 patients aged from 10 to 15 whom were admitted to the department of orthodontics of Mashhad dental school. On hand-wrist radiographs, skeletal maturation was assessed by means of TW3 method.Cervical vertebrae maturation was evaluated on lateral cephalogram using the methods described by Lamparski, Mito, Roman and Hassel & Farman. Correlation coefficient was determined between skeletal maturation values based on cervical vertebrae and hand-wrist radiographs by Pearson and Spearman analysis.Results: Correlation coefficient between cervical vertebral age (using Lamparski's method) and skeletal age (using TW3 method) was 0.81. For Mito's, Roman's and Hassel & Farman's methods the correlation coefficient was 0.80, 0.997 and 0.995 respectively. No significant correlation was revealed between cervical vertebral bone age (using Mito's & Lamparski's methods) in 10-13 year old boys and that of hand-wrist base (P>0.05).Conclusion: In all groups using, Roman's and Hassel & Farman's methods had a high correlation between cervical vertebrae and hand-wrist skeletal maturation. So, these two methods can be used as relable alternatives for hand-wrist radiograph in skeletal maturation evaluation.

Introduction: Previous studies have shown that in reimplanted immature teeth, pulp revascularization is relatively low.This study investigated the effect of topical doxycycline on pulp revascularization in replanted immature dog teeth.Materials & Methods: in this experimental study, 32 immature anterior dog teeth with 3-4 month age were extracted and kept in normal saline for 30 min. In group I, 16 teeth were replanted and in group II, 14 teeth were soaked in doxycyline for 5 min (1mg /10 cc saline) and then replanted. The observation time was 6-8 weeks. Next, the dogs sacrificed using vital perfusion method. After that, the teeth with surrounded tissue were removed in tissue blocks, histologically processed and evaluated by a pathologist and a microbiologist for presence of capillary in the lumen, odontoblastic layer, inflammation and microorganism. The results were statistically analysed using Mann-Whitney test.Results: It was revealed that topical application of doxycycline increased pulp revascularization (P=0.017) and frequency of new odontoblasts (P=0.035) and also decreased inflammation (P=0.027) in the pulpal lumen.Conclusion: The present study showed that topical treatment with doxycycline (1mg/10ml saline) for 5 minutes facilitated pulp revascularization in replanted immature teeth after replantation.

Introduction: The incidence of pain after root canal treatment is one of the main problems for patients and dentists.Many studies have been done on analgesics for alleviating pain after treatment. The purpose of this study was the comparison of analgesic effects of Tramadol and Ibuprofen after root canal treatment.Materials & Methods: In this clinical trial study, 40 patients who had vital one canal teeth were selected randomly.The patients were divided into two groups of A and B. The drugs were prepared identically as capsules containing 400mg of Iboprofen or 100mg tramadol hydrochloride. The patients were given one capsule followed by additional one capsule every 6 hours if the pain persisted.The patients were controlled for 3 days. The data were collected through a special chart at time intervals of 12, 24, 48 and 72 hours after treatment and finally were analyzed using Mann-Withney test with 95% confidence level.Results: The results showed that there was no significant difference between tramadol prescription compared with ibuprofen in 12 hour interval, but in 24, 48 and 72 hours after treatment, the difference was significant and the analgesic effect of tramadol was more than ibuprofen.Conclusion: Tramadol prescription compared with Ibuprofen has greater analgesic effect after root canal treatment in vital teeth after 12 hours and can be more effective than ibuprofen for severe pain relief.

Introduction: Radiography is the most common method for measurement of working length, but it is not the ideal method. The application of radiography in children is more dangerous and difficult in respect to radiation hazard, technical problems, superimposition of permanent teeth bud on primary teeth, and so on. Electronic Apex Locator (EAL) is a device for determination of working length. In the present study, we evaluated the in vitro accuracy of EAL in Measuring resorbed root canal length in primary teeth.Materials & Methods: This analytical-descriptive study was conducted on 112 canals of extracted primary teeth that had at least 2.3 of root length. After preparation of the access cavity and removing pulp chamber tissue, the lengths of the canals were measured by Dentaport ZX and the real length of the canals were determined straightly with 0.5 mm accuracy. Then two measurements were compared. Data were analyzed by paired T test and intra class correlation and p<0.05 was considered as the limit of significance.Results: The accuracy of Dentaport ZX for carefully determination of apical foramen was 52.7% and in the range of -0.5 to +0.5 mm from apical foramen was 91.1%. There were a straight powerful linear correlation between measurements by eye and Dentaport ZX.Conclusion: According to the results of this study, using Dentaport ZX in endodontic treatment for primary teeth especially for non-cooperative children is recommended.

Introduction: According to the increase in producing of amalgam in our country and because of the costness of this material it is necessary to compare an Iranian amalgam with non-Iranian amalgam. The objective of this one-year study was to evaluate the clinical criteria of recurrent caries, marginal adaptation, anatomic form, surface morphology and surface luster in class II amalgam restorations.Materials & Methods: In this clinical trial study, thirteen participants aged 20 to 35 years were selected.  Two premolars of each one were prepared for normal class II cavity preparations and then were restored with two types of spherical high copper amalgams (Sina, Coeten). Next, according to USPHS system, the clinical criteria were evaluated in three intervals; immediately after restoration, 6 months and 12 months after treatment. For comparison of two amalgams in respect to clinical criteria, chi-square test was used (a=0.05).Results: a-Rating for all of the criteria in two amalgams after 6 months showed a reduction in comparison with baseline and also after 12 months compared with six month period. There was no significant difference in clinical criteria in each time interval for two amalgams (P>0.05). The most reduction in a-Rating was seen in surface luster of Sina but this was not statistically different from Colton.Conclusion: After one year, the recurrent caries was observed in gingival floor of class II high copper amalgam restorations which was more significant than the other factors.

Introduction: When the prosthetic treatment of whole masticatory system and patient occlusion are done, the duration time of temporary restoration increases. In this period, one temporary restoration should have the properties of an ideal prosthesis. Therefore, the material selection for making a temporary restoration is important. The aim of this experimental study was the comparison of marginal integrity of temporary crowns made from two types of temporary materials; self cured acrylic resin (Tempron), and light cured composite resin (Revotek.lc).Materials & Methods: In this experimental invitro study, 20 brass dies with 1mm width shoulder finishing line were prepared which had 7mm height, 7mm basal diameter and 8 degree convergence angle. A coping was made from the brass sleeve for each die to build up the prepared form. Dies were divided into two groups of 10, and then the temporary restoration was made directly. After cementation of cases on related dies, the marginal gap was scaled by a microscope with 100 degree magnification. Next, they were put under occlusal load (40N) for 50000 cycles and 3400 cycles of thermocycling (5-55oc). Finally, the marginal gap was scaled in post dot. Data analysis was done by student t-tests with 95% significance level.Results: 1. The average marginal gap in self cured acrylic resin before occlusal load and thermocycling was less than light cured composite resin, but this difference was not significant (P=0.19). 2. The difference of marginal gap between Tempron and Revotek after occlusal load and thermocycling was not significant (P=0.48). 3. The comparison of gap before and after thermocycling and occlusal load revealed that marginal gap decreased after thermocycling and occlusal load in Revotek more significantly than Tempron (P=0.042).Conclusion: The results of this study showed that Tempron and Revotek lc in both invitro and direct fabrication had good marginal integrity before and after occlusal load and thermocycling, but Revotek lc revealed a better result in gap reduction.

Introduction: Use of light-Curing units is an inseparable part of dentistry. They are used for curing conventional composites, glass inomers, and liners and for bonding orthodontic brackets. It is then necessary to evaluate recently developed light curing units (LED) and compare them to conventional halogen units at different distances. This study aimed to compare the effect of LED and Halogen light curing units at different distances on composite (Z250) microhardness.Materials & Methods: Microhybrid composite (Z250) with a Bis-GMA base (3M, ESPE) was used in this in vitro study.Plexiglass molds were provided with 10×10cm size and 2mm height and filled with composite Z250. Samples were then devided into four groups of ten each. Samples in the first group were cured using Halogen light curing unit (Astralis 7) at 0mm. Second group were cured using Astralis 7 at 5mm. Third group were cured using Apoza light Curing unit at "0mm" and the fourth group were cured using Apoza light curing unit at "5mm". After 20 second curing, samples were held in room temperature for 24 hours. Then microhardness test (Vickers, model 6100) was performed, over three separate points with distance of 1mm with each other on superior and inferior surfaces of each samples. The analysis was done with ANOVA.Results: Statistical analysis revealed that microhardness on superior surface of Astralis 7 group at both “0mm and 5mm” was significantly higher than Apoza group. It was also revealed that microhardness in both units at “0mm” was significantly higher than “5mm”. BTR (bottom / top Ratio) at LED (Apoza) was significantly higher than Halogen (Astralis 7).Conclusion: Microhardness of all samples at a distance of “0mm” was significantly higher than samples curing at a distance of “5mm”. Microhardness of Z250 on superior surface after curing with Astralis 7 (Halogen) was significantly higher than samples curing with Apoza (LED) light curing unit. BTR at LED was significantly higher than Halogen.

Introduction: Dental Aesthetic Index (DAI) is an orthodontic index on the basis of aesthetic standards defined by the community. The main goal of this study was to evaluate the orthodontic treatment needs of 14-18 year-old students in Shiraz using DAI.Materials & Methods: Using random cluster sampling process in this descriptive-analytical study, 1818 students (965 boys and 853 girls) who were 14-18 years old without any orthodontic treatments were selected. The information was gathered by the method recommended by World Health Organization (WHO) and using a questionnaire that contained demographic characteristics. The data were analyzed by chi-square and T-tests.Results: In 12.3 % of students, treatment was highly needed and in 8.1% of them treatment was mandatory. There was a significant difference in DAI score between girls (27.2) and boys (25.9) (P<0.001). About half (48.3%) of samples did not need orthodontic treatment and almost one fifth of them (21%) had severe malocclusion who needed orthodontic treatment.Conclusion: Orthodontic treatment need in adolescent students of Shiraz was comparable to Spanish adolescents, more than Caucasians of Australia and Nigerian people but less than Japanese adolescents.

Introduction: Facial growth pattern especially the mandible is one of the important factors in diagnosing and treatment planning. There are some parameters for evaluation of the growth pattern that symphysis morphology is one of them.The aim of this study was to evaluate symphysis morphology in different growth patterns and malocclusions of Iranian orthodontic patients to determine correlation and relation between them.Materials & Methods: This descriptive cross-sectional study was carried out on 150 cephalometric radiographs of the patients (72 males and 78 females) who had been selected through non probability sampling method. These patients were 13 to 26 years old with mean of 19.1±2.2 years. Height, Dept.h, ratio and angle of symphysis were measured and compared with sagittal & vertical parameters in cephalomtric radiographs. The data were analyzed & compared using ANOVA, and Pearson correlation test through SPSS software.Results: The results showed that there was a significant correlation between symphysis morphology as height, ratio and angle of symphysis with growth pattern of the patients (P<0.01). However, this relation in Dept.h of symphysis was not significant (P>0.05). This study showed that longer symphysis (28.5±2.4), greater height to Dept.h ratio (2.5±2.5) and acute angle (76.3±3.3) of symphysis to mandibular plane were accompanying with vertical growth pattern, while, shorter symphysis (20.2±1.9), less height to Dept.h ratio (1.2±0.4) and obtuse angle (83.8±1.9) of symphysis to mandibular plane were accompanying with horizontal growth pattern.Conclusion: Symphysis ratio (height to Depth) is the most important index of symphysis morphology and could be used as an easy way in determining growth pattern.

Introduction: Hemophilic patients need special care and attention in dentistry. The purpose of this study was to evaluate the oral and dental health of hemophilic patients in Khorasan Province in 2003.Materials & Methods: This descriptive analytical study was performed on 42 hemophilic patients (7-34 years old) in Khorasan Hemophilia Center in 2003 during the past six months. Demographic characteristics and a history of coagulation problems and the related treatments were filled for patients. DMFT and modified gingival index (MGI) were recorded for them. Data were analyzed using Mann Whitney, Fisher’s exact and Kruskal Wallis tests.Results: Common age for the first manifestations was between 6-12 months (81%). Familial involvement was reported in 47.6% of patients. The most common dental problem was bleeding during eruption or exfoliation of deciduous teeth (31%). Viral infection with HBV or HCV was reported in 40% of cases. DMFT Index significantly increased by age in this study (6.2±2.5 in 7-12 year old and 13.1±3.2 in ³25 year old patients). DMFT index was over 10 in 42% of patients. MGI index had a significant increase by age (P=0.01). 66.7% of 25 year and above patients had third grade gingival inflammation.Conclusion: Regarding the unsatisfactory oral health status in these patients, dental health care and prevention seems necessary and can be effective in prevention of dental problems and the consequent bleedings and the complex treatments.

Introduction: Different systems are introduced for orthodontic treatments. Two common systems which are used today are standard edgewise and straight wire methods. For comparing treatment outcomes, occlusal indices have greatest validity. Also buccolingual inclination and mesiodistal angulations of teeth may have a great effect on treatment results. In this study we used Peer Assessment Rating Index (PAR) and Andrews' standards for comparing of treatment outcomes of these two systems. The purpose of this study was to compare the changes of PAR index and buccolingual inclination and mesiodistal angulations of teeth during orthodontic treatment of class I patients by means of standard edgewise and straight wire methods.Materials & Methods: In this descriptive analytical study 100 study models (pre-treatment and post treatment) of 50 classes I patients were evaluated by PAR index and Andrews' standards. Twenty five class I patients treated with standard edgewise method and twenty five class I patients treated with straight wire method were selected among the patients of a private clinic. Occlusal characteristics and buccolingual inclination and mesiodistal angulations of all teeth were measured on the study models, respectively before and after treatment. Then PAR index and buccolingual inclination and mesiodistal angulations of the teeth were compared between the two groups by means of Student-t and Mann-Whitney tests. The level of significance was set at 95%.Results: There was no significant difference in sex and age between two groups of patients. PAR index did not show a significant difference between the two groups. Comparison of buccoligual inclination and mesiodistal angulations of teeth with Andrews' standards did not show any significant difference between the two groups except for mesiodistal angulations of the upper central incisors and buccolingual inclination of the upper incisors. These parameters were closer to Andrews' standards in straight wire group. Duration of treatment and number of visits were significantly less in straight wire group than standard edgewise.Conclusion: Occlusal characteristics according to PAR index and buccolingual inclination and mesiodistal angulation of teeth (except for mesiodistal angulations of the upper central and buccoligual inclination of the upper incisors) were similar in edgewise standard and straight wire methods. Straight wire treatment goals were accomplished in shorter duration than standard edgewise treatment.

Introduction: Granular cell tumor is a benign and nonprevalent tumor with unknown etiology that frequently presents as a nodule in oral mucosa with a diameter less than 2cm without signs and symptoms. However it can appear as an ulcer or a mass with keratotic surface. In this article three case of lingual granular cell tumor referred to oral medicine department of Mashhad dental school were reported.Results: In all patients, a firm nodule on lateral border of tongue was seen but different changes in surface of lesions such as keratosis and ulcer and roughness suggested the diagnosis of squamous cell carcinoma. The diagnosis of granular cell tumor was confirmed by histopathologic examination and lesions were completely excised.Conclusion: Probable pseudoepitheliomatous hyperplasia, roughness on the surface, ulcer or keratosis of these kinds of lesions could lead to Clinical and hisopathologic misdiagnosis. It is necessary to be aware of all kinds of clinical manifestation of granular cell tumor and differentiate it from other lesions such as mesenchymal tumors or reactive lesions such as irritation fibroma and malignant epithelial lesions such as squamous cell carcinoma.