Showing 150 results for Zadeh
Hadi Asgharzadeh Shirazi, Mohammadreza Mallakzadeh,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: Hydroxyapatite coating has allocated a special place in dentistry due to its biocompatibility and bioactivity. The purpose of this study was to evaluate the relation between the hydroxyapatite thickness and stress distribution by using finite element method.
Materials and Methods: In this paper, the effect of hydroxyapatite coating thickness on dental implants was studied using finite element method in the range between 0 to 200 microns. A 3D model including one section of mandible bone was modeled by a thick layer of cortical surrounding dense cancellous and a Nobel Biocare commercial brand dental implant was simulated and analyzed under static load in the Abaqus software.
Results The diagram of maximum von Mises stress versus coating thickness was plotted for the cancellous and cortical bones in the range between 0 to 200 microns. The obtained results showed that the magnitude of maximum von Mises stress of bone decreased as the hydroxyapatite coating thickness increased. Also, the thickness of coating exhibited smoother stress distribution and milder variations of maximum von Mises stress in a range between 60 to 120 microns.
Conclusion: In present study, the stress was decreased in the mandible bone where hydroxyapatite coating was used. This stress reduction leads to a faster stabilization and fixation of implant in the mandible bone. Using hydroxyapatite coating as a biocompatible and bioactive material could play an important role in bone formation of implant- bone interface.
Hoorieh Bashizadeh Fakhar, Elham Sadat Emadian Razavi,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims Bone density is frequently used in medical diagnosis and research. The current methods for determining bone density are expensive and not easily available in dental clinics. The aim of this study was to design and evaluate the accuracy of a digital method for hard tissue densitometry which could be applied on personal computers.
Materials and Methods: An aluminum step wedge was constructed. 50 E-speed Kodak films were exposed. Exposure time varied from 0.05s to 0.5 s with 0.05 s interval. Films were developed with automatic developer and fixer and digitized with 1240U photo Epson scanner. Images were cropped at 10 × 10mm size with Microsoft Office Picture Manager. By running the algorithm designed in MATLAB software, the mean pixel value of pictures was calculated.
Results: Finding of this study showed that by increasing the exposure time, the mean pixel value was decreased and at step 12, a significant discrimination was seen between the two subsequent times(P<0.001). By increasing the thickness of object, algorithm could define the density changes from step 4 in 0.3 s and 5 in 0.5 s, and it could determine the differences in the mean pixel value between the same steps of 0.3 s and 0.5 s from step 4.
Conclusion: By increasing the object thickness and exposure time, the accuracy of the algorithm for recognizing changes in density was increased. This software was able to determine the radiographic density changes of aluminum step wedge with at least 4mm thickness at exposure time of 0.3 s and 5 mm at 0.5 s.
Hoorieh Bashizadeh Fakhar, Hanieh Kaviani, Mehrdad Panjnoosh, Ahmad Reza Shamshiri,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: It is crucial to verify the relationship between root apices and maxillary sinus floor in some surgical procedures like extraction and implant placement or in orthodontic movements like intrusion. Protrusion of roots into the sinus increases the risk of post extraction pneumatization which in turn decreases the available bone at the implant or denture sites. The aim of this study was to determine the panoramic radiology accuracy for defining the relationship between posterior root apices and the maxillary sinus floor by Cone Beam CT (CBCT).
Materials and Methods: Paired panoramic radiographs and CBCT images of 117 subjects were examined. 452 posterior maxillary roots including second premolar, first and second molar were classified by the means of the relationship with maxillary sinus floor. CBCT was used as Gold standard method, and the agreement of panoramic findings with CBCT was examined statistically. Data were analyzed using Chi-square and Multiple logistic regressions.
Results: Agreement of the panoramic and CBCT results were seen in 57.7% of all cases. Roots which had no contacts with the sinus floor (class 0) showed a high agreement of 89.5% between two imaging techniques. Roots in contact with sinus floor (class 1) showed 58.8 % and cases with root protrusion into sinus cavity (class 3, 4) showed 50% of agreement (P<0.001). Also in 36% of cases with no protrusion into the sinus cavity (class 0, 1, 2), panoramic showed protrusion. The agreement for the premolar was higher than molars (P<0.001)
Conclusion: The majority of roots which their images were projected on the sinus cavity had no vertical protrusion in CBCT cuts. Considering the results, in these cases CBCT can be recommended.
Jalil Modaresi, Vahid Shirani, Mohammad Malekzadeh,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: Electric pulp tester is a valuable instrument to examine tooth’s pulp vitality. There is no agreement about the response of immature teeth to electric pulp tester and the reason is expressed as the failure of nerve fibers’ development. The aim of this study was to investigate the effect of patient’s age on the tooth response to electric pulp tester.
Materials and Methods: In this cross-sectional study, 300 maxillary central permanent teeth in 150 volunteers were examined by using electric pulp tester. The volunteers were classified in 5 age groups of 7-8, 9-10, 11-12, 13-4, and 30-35 and teeth lacking sound and healthy pulp were excluded. Data were analyzed using SPSS-16 software, one-way analysis of variance, and Tukey post hoc test.
Results: The average response to electric pulp tester in age groups of 7-8, 9-10, 11-12, 13-4, and 30-35 years old were 2.9±0.1, 2.8±0.1, 2.3±0.1, 2.2±0.1 and 1.8±0.1 ,respectively. This indicated that by increasing teeth age, they responded to lower level of electric pulp tester. In subjects less than 14 years old, there was no significant difference between neighboring groups (P=0.3) however, a significant difference was observed between subjects less than 14 years old and adults (P<0.001).
Conclusion: This study showed that immature teeth responded at higher levels to electric test however, all teeth responded to electric pulp tester.
Mehdi Jafarzadeh, Maryam Haji Ahmadi, Hajar Esmaielian, Hadi Moshkel Gosha,
Volume 27, Issue 3 (9-2014)
Abstract
Background and Aims: Successful pediatric dentistry depends on the dentist's technical skills, as well as his/her ability to acquire and maintain a child's cooperation. The correction of dentist’ performance in this area affects the view of parents and increases the quality of dental services. The aim of this study was to evaluate the attitudes of general dentists toward behavior guidance techniques in Isfahan.
Materials and Methods: In this descriptive- analytic cross-sectional study, 100 general dentists of Isfahan city were selected with simple random sampling technique. They were asked to complete the questionnaire inquiring their attitude toward four different behavioral management techniques . An appropriate question about each of the methods was proposed by the authors, along with demographic characteristics including: gender, age, university, year of graduation, work experience, the mean number of pediatric patients referred in one month was provided in the form of a questionnaire. To evaluate the attitude of dentists to the questionnaire, the score from 1 to 5 was given to each item and the total score was considered. Higher score indicated more positive attitude of dentist. Data were analyzed using T-test, Pearsons correlation and one-way ANOVA (P<0.05).
Results: The mean scores for dental behavioral management techniques were positive reinforcement (4.2±2.7), general anesthesia (3.5±4.4), N2O sedation (3.4±4.4) and pharmacologic sedation (3.2±2.7), respectively. There were no significant differences between the mean score of dentist attitude and age, gender, clinical experience and the number of pediatric patient (P>0.05).
Conclusion: General dentists’ attitudes towards different behavior management techniques were associated with age, gender, clinical experience and the number of pediatric patient. General dentists’ tend was more towards non-drug behavior control methods such as positive reinforcement.
Davari Abdolrahim , Daneshkazemi Alireza , Modaber Maryam , Malekzadeh Mohammad ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: The most effective preventing tooth decay method is fluoride compounds applications. Some studies suggested that APF gels caused changes on the superficial physical properties of composite. Therefore, the purpose of this study was to evaluate the marginal microleakage of class V composite restorations before and after AFP gel application.
Materials and Methods: The class V cavities in buccal surfaces of 45 molar teeth were made in such a way that occlusal margin was placed in enamel and cervical margin in cement. In group 1, at first fluoride-therapy and then cavity preparation and restoration by composite resin was done. In group 2, at first the class V cavities were prepared and restored, then fluoride-therapy was carried out. In group 3, cavities were prepared and restored with no fluoride-therapy. The dye penetration rate in occlusal and cervical margins was examined by stereomicroscope. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney test.
Results: There was no statistically significant difference between groups ( P=0.975).
Conclusion: Fluoride-therapy using AFP gel before and after class V composite restorations, had no significant effect on the microleakage of dentin and enamel margins.
Feizi Ghader , Kaviani Naser , Mehrparvar Roza , Binandeh Elham Sadaat , Tabrizizadeh Mehdi , Saatchi Masoud ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Postoperativee endodontic pain is an outstanding problem for dental patients. Therefore, a successful management of endodontic pain has become as one of the main dental objectives. The aim of the present study was to compare the postoperative endodontic pain in patients under general anesthesia versus local anesthesia.
Materials and Methods: For conducting this clinical trial study, 50 patients having mandibular molars candidate for root canal therapy were selected. Twenty-five patients treated under general anesthesia because of their fear, anxiety or gag reflex. Other 25 patients treated under local anesthesia. All teeth were prepared using engine-driven rotary system in a crown-down technique and filled using lateral condensation technique. Heft- parker visual analog scale was used to measure the degree of pain at 6, 12, 24, and 48 hours after the treatment. Mann-Whitney, Chi-square, and T-tests were used to compare the intensity of postoperative pain between the groups.
Results: The mean intensity of postoperative pain in local and general anesthesia groups at 6, 12 and 24 hours had statistically significant difference (P<0.05).
Conclusion: Postoperative pain in patients who treated under general anesthesia was significantly less than the patients who treated under local anesthesia.
Arami Sakineh , Aghasadeghi Mohamadreza , Tabatabaie Masome Hasani , Darvishpour Hojat , Sheikhzadeh Sedigheh ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Hepatitis B is an important infection route in dentistry requiring different disinfectants to prevent its transmission. The aim of this study was to compare the effects of chemical disinfectants (FD366, ISORAPID and 5% sodium hypochlorite 2/100) to remove Hepatitis B infections from the dental surfaces.
Materials and Methods: In this experimental laboratory trial, serum of 10 HBV patients was poured into microtubes, FD366, ISORAPID and hypochlorite disinfectants were added to them. PCR experiments with viral diagnostic kits were used to diagnose the virus genome. Real time PCR was used to evaluate after incubation with the disinfectants. The reductions occurred in the viral load of Hepatitis B were statistically analyzed using Kruskal-wallis and Mann-Whitney U tests .
Results: No significant antiviral efficacy was noted following the application of FD366 and ISORAPID disinfectants (P=0/07). However, hypochlorite showed the most efficacy to disinfect Hepatitis B and a significant difference was found among them (P<0.0001).
Conclusion: Under the study limitations, FD366 and ISORAPID disinfectants did not show adequate efficacy to remove Hepatitis B virus. Hypochlorite was the most effective disinfectant.
Sahebi Majid , Hajizadeh Moslem ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Temporomandibular joint disorders are common problems among patients referring to dental schools and clinics. However appropriate treatment modalities are performed for the TMD patients in dental school, the results and success rate of these treatments are not studied distinctly. The aims of this study was to determine the treatment performed for temporomandibular patients at the TMJ department of Tehran University dental school in 2010-11 .
Materials and Methods: In a descriptive cross-sectional trial, 85 TMD patients treated at the TMJ department of Tehran University dental school were examined at least 3 months after the treatments. The patients demographic data ,TMD signs and symptoms and the improvements occurred in TMD disorder were determined (complete, partial and no improvement). The patients satisfaction regarding the treatment results were investigated and data were analyzed regarding the presence of different TMD signs and symptoms before and after the treatment using Mann-Whitney U test .
Results: TMJ pain (35 cases, 42.2%), click (33 cases, 39.8%) and muscle tenderness (26 cases, 31.3%) were the most prevalent obtained signs and symptoms. The mean age of the patients were 32.3 years old while females were the predominant group (72 cases vs.11 one). 44 individuals (53.0%) were treated by splint, 11 ones (13.3%) with anterior repositioning splint and 17 individuals (92.5%) were managed by physiotherapy plus splint. 65 patients (87.3%) were satisfied with the results and 16 ones (19.3%) were not. After the treatment, patients with TMJ pain (P<0.001) and muscle tenderness (P<0.001) showed significantly lower satisfaction than that of patients with no signs. No other significant differences were noted between patients satisfaction regarding the presence of TMD signs and symptoms (P>0.05) .
Conclusion: The results showed that the treatments presented for the TMD patients at Tehran University dental school were successful and most patients received satisfactory treatment.
Sandra Mehralizadeh, Peyman Mehrvarzfar, Sima Taghizadeh, Maryam Edalat, Mahashad Mohebi,
Volume 28, Issue 2 (7-2015)
Abstract
Background and Aims: Diagnosis of vertical root fractures often poses a clinical dilemma. Diagnosis of VRF in intraoral radiographs, except in cases where the beam is perpendicular to the direction of fracture is difficult. Misdiagnosis often leads to wrong decisions about the design of teeth future treatment plan. The aim of this study was to determine the diagnostic accuracy of reverse contrast enhancement options in digital radiography, and to compare it with the original images to find a suitable method to detect vertical root fracture.
Materials and Methods: In this experimental study, digital radiography with phosphor plate detector was taken from 40 extracted single root teeth. From each intact and fractured tooth, the original and reverse contrast images captured and stored. Two expert observers viewed the images twice with an interval of two weeks. Diagnostic criteria (Accuracy, PPV, NPV, Specificity and Sensitivity) in form of absolute and complete for each observer and each images was calculated. Inter and intra observer reliability was obtained using Mc-Nemar test.
Results: No significant differences in inter-observer reliability between the initial appearance and reverse contrast was observed (P>0.05), but in view of the intra-observer reliability in two cases, the difference was significant (P<0.05). No significant difference in the accuracy, sensitivity, specificity and PPV was observe between the two used images (P>0.05), whereas significant difference between the two images was found in NPV index (P<0.05).
Conclusion: The use of reverse contrast enhancement option for detection of vertical root fracture did not show significant difference from initial view.
Mohsen Shirazi, Yasamin Farajzadeh Jalali, Hojat Darvishpour,
Volume 28, Issue 3 (10-2015)
Abstract
Background and Aims: Cleft lip and palate patients require orthodontic treatments during their childhood and adolescence. Tweed diagnostic triangle as well as cephalometric assessments provides important data regarding the skeletal patterns for the treatment and diagnostic purposes. The present study determined the cephalometric changes of Tweed triangle in the cleft lip and palate patients compared to normal patients.
Materials and Methods: In total, 101 cleft and palate patients as well as 95 normal individuals with the balanced age, gender and race were evaluated. All the cleft and palate patients had similar treatment histories. Radiographic clichés were obtained from both groups and the images were traced after identifying the anatomic landmarks. The studied landmarks included points, lines, and plans as well as dental and skeletal angles and distance ratios measured in radiographic images. The landmarks were statistically analyzed using Student t test.
Results: Significant differences were found between the cleft lip and palate patients and normal individuals regarding craniofacial complex morphology (P<0.001). Gender did not show significant effect on the cephalometic indices changes (except to IMPA and FMIA angles). Tweed angle changes were more in the males than that of females between normal and cleft lip and palate patients. Mandibular retrusion (decreased SNB), gonial angle opening, increased mandibular plan inclination and facial anterior height were similar in the normal and cleft lip and palate individuals while no significant differences were found between two groups regarding cranium indices (P>0.05).
Conclusion: In total, significant differences were observed between normal and cleft lip and palate individuals regarding Tweed diagnostic triangle area. These differences were decreased IMPA and increased FMA and FMIA angles. No significant differences were found in terms of other indices.
Reza Masaeli, Tahereh Sadat Jafarzadeh Kashi, Farhad Shafiei,
Volume 28, Issue 3 (10-2015)
Abstract
Poly (lactic-co-glycolic acid) is a biodegradable polymer which has used in a different fields of medical applications. As PLGA is approved by FDA(food and drug administration) the range of this usage is increasing in comparison to the past. Particularly, PLGA are also developed for the dental field in the form of scaffolds, films, membranes, microparticles, or nanoparticles. PLGA scaffolds have been used to regenerate damaged tissues together with stem cell-based therapy. There is solid evidence thatthe development of PLGA microparticles and nanoparticles may be beneficial to a wide range of dental fields such as endodontic therapy, dental caries, dental surgery, dental implants, or periodontology. The aim of the current paper was to review the recent advances in PLGA materials and their potential uses in Dentistry via exploring related literature during 2004 till 2016 in Science Direct and PubMed.
Seyedeh Tahereh Mohtavipour, Somayeh Nemati, Alieh Sadat Javadzadeh Haghighat, Seyedeh Saeedeh Mohtavipour, Mina Sadadt Mirkhani,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: Elongation of styloid process may result in development of Eagle syndrome with associated symptoms. This study aimed to assess the frequency of elongated styloid process (ESP) and to evaluate its prevalence according to sex and age.
Materials and Methods: This study was conducted on digital panoramic radiographs of patients refered to the Oral Radiology Department of dental school, Guilan University of Medical Sciences. Styloid process length was measured and classified as elongated, pseudoarticulated, or segmented. Calcification patterns were determined as A, B, C, and D. ESP was defined as length > 30 mm. Data were analyzed by SPSS using T-test, Chi square, Pearson, and Spearman (P<0.05).
Results: A total of 505 digital panoramic radiographs taken from 227 males (45%) and 278 females (55%) aged 10 to 72 (40.1±12.9) years were evaluated. Elongated styloids were present in radiographs of 230 (45.5%) individuals. There was no significant difference in the ESP frequency between males (46.09%) and females (53.91%) (P=0.63). Type I and calcification B pattern showed more frequency than that of other categories.
Conclusion: According to these findings, elongated styloid process was a common condition among the studied population and had a significant correlation to the age.
Farnaz Farahat, Abdolrahim Davari, Motahare Amiri, Ebrahim Mokarizadeh,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: Dental erosion refers to the loss of tooth structure by being scratched chemically without bacterial involvement which needs to care about due to its prevalence and treatment problems. This study was designed with the aim of evaluation of the frequency of dental erosion and its causing factors in patients referring to yazd dental school in 2012-2013.
Materials and Methods: In this cross-sectional study, 400 patients referring to yazd dental school were randomly selected. All of their teeth were evaluated in three surfaces (buccal, lingual and occlusal). The BEWE score was used for classification the extent of damages. Also, patients were given a questionnaire that included patient demographic information and questions to investigate the causes of dental erosion. Data were analyzed using SPSS version 17 and Mann-Whiney, Fisher exact, and Chi-square tests.
Results: In this study, 138 men and 261 women were participated with the mean age of 33.26±10.83. 84 persons (21.1%) had erosion. There was a direct and significant relationship between the dental erosion and patient's age (P >0.001). Also, there was a direct relationship between the dental erosion and reflux and consumption of lemon and pickle, beverages, soft beer and juice (P>0.001).
Conclusion: Consumption of lemon and pickle, beverages, soft beer and juice increases the risk of erosion. Considering the prevalence of dental erosion in about 21% of patients, it is necessary to pay more attention to the knowledge of the causes of erosion and reduction strategies of it.
Hadi Ghasemi, Arezoo Ebnahmadi, Maryam Moezzyzadeh, Masoud Geramipour,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: Dental students’ evaluation of teachers’ educational activity is crucial for the improvement of dental school’s performance. The process of the evaluation needs a valid and reliable tool. This study aimed to produce and validate a questionnaire for the evaluation of dental school teachers by students.
Materials and Methods: A group of 15 teachers in the Shahid Beheshti dental school gave their opinions regarding the characteristics of an ideal teacher using nominal group technique. These characteristics together with characteristics gathered from similar studies made the base of a questionnaire which later underwent a validity and reliability assessment by means of the calculation of Content Validity Index (CVI), Content Validity Ratio (CVR), and Cronbach’s alpha coefficient.
Results: The preliminary questionnaire included 94 items in four categories naming: ethics, educational capability, practical capability, and managemet. After calculating CVR and CVI for each item, 23 items with CVR<0.33 and 20 items with CVI<0.79 have been excluded from the questionnaire leaving a questionnaire with 54 items. The overall reliability of this questionnaire using Chronbach’s alpha coefficient was 0.96.
Conclusion: Consulting an expert group that are familiar with different aspects of educational performance of faculty teachers, it was concluded that applying various methods for validity and reliability, and considering local culture values are useful for the preparation of the questionnaire for similar studies in Iran.
Saeed Nemati Anaraki, Hamed Karkehabadi, Nazanin Zeinab Garshasb Zadeh,
Volume 29, Issue 1 (7-2016)
Abstract
Background and Aims: Microleakage is one of the most common problems in bonding systems, which cause different clinical shortcomings such as post operative sensitivity, marginal discoloration and pulp necrosis that can decrease those using bonding systems. The aim of this study was to compare the microleakage of three self etch bonding agents (generation 6 and 7) in class 5 composite cavities.
Materials and Methods: In this experimental study, 30 facial class 5 cavities were prepared in 30 human premolar teeth which were freshly extracted for orthodontic purposes. Cl V cavities were prepared in 2*3*2 mm dimensions. Occlusal margins were in enamel and gingival ones in cementum and randomly divided into 3 groups of 10 each. Then the cavities were treated by clearhil SE Bond (Kuraray, Japan), G Bond (GC, Japan), and Opti Bond Solo Plus (Kerr, USA), according to the manufacturers’ insductions. Then the cavities were filled using Z100 resin composite. The specimens were then immersed in a 50% AgNo solution for 24 hrs. Then, the teeth were cut buccolingually to be evaluated for dye penetration with stereomicroscope. Data were analyzed using Kruskal-Wallis test.
Results: This study revealed that Opti bond solo plus had type1 microleakage (dye penetration up to 1/3 of cavity) in 80% of specimen, and type 4 microleakage (along axial wall) in 10%. Clearfil SE bond had no leakage in 50%, type1 in 40% and type 2 (up to 2/3 of cavity) in 10%. But there was no significant difference in the microleakage at the gingival margins between 3 groups (P>0.05).
Conclusion: Clearfil SE Bond and G bond could prevent microleakage more effectively than that of Opti Bond Solo Plus on the occlusal margins. However, no difference in the microleakage on the gingival surfaces was found.
Ali Eskandarizadeh, Shahram Farzin Ebrahimi, Niloofar Shadman, Saeed Rahmani,
Volume 29, Issue 1 (7-2016)
Abstract
Background and Aims: Slow polymerization rate in early stage of light curing process leads to higher monomers movement and entering in polymer network that cause higher mechanical properties.The aim of this study was to evaluate the effect of light activation methodes (immediate, 5 and 10 minutes delay) on the push-out bond strength of cemented fiber posts in different regions of root canal with two types of resin cements.
Materials and Methods: In sixty extracted human single canal, the teeth were decoronated from cement enamel junction and after root canal therapy, FRC postec plus were cemented with two resin cements, Duolink and Variolink 2, in three curing methods; immediate, 5 and 10 minutes of delay. After storing in a dark place for 24 hours, they were cut into three sections: coronal, middle and apical. The push-out bond strength test was performed using a universal testing machine. The failure modes were observed using a stereomicroscope. Data were analyzed using ANOVA and Tukey post hoc test (P<0.05).
Results: In Duolink, immediate light curing had significantly higher bond strength than that of two delayed methods (P>0.05). In immediate light curing method, regardless of root region, Duolink had higher push-out bond strength than that of Variolink 2 (P=0.02). In all subgroups, there were reductions in the bond strengths from coronal to apical. Mixed failure at the cement-fiber post interface was predominent in all groups.
Conclusion: 5 and 10 minutes delay caused reduction in the push-out bond strength for Variolink 2 but did not have significant effect for Duolink resin cement.
Mohtavipour Seyedeh Tahereh , Seyedeh Saeideh Mohtavipour, Alieh Sadat Javadzadeh Haghighat, Shiva Sadeghi, Maryam Rezvani, Bahar Mahmoud Khalesi,
Volume 29, Issue 1 (7-2016)
Abstract
Background and Aims: Estimating the canal length is essential for reaching to a proper endodontic treatment. Any error and miscalculation in estimation of the working length, especially in curved canals, can result in complication during and after root canal therapy. The introduction of digital radiography has enabled us to measure curved canal length. The purpose of this study was to evaluate the calibration tool of Complementary Metal Oxide Semiconductor (CMOS) digital system in estimation of working length.
Materials and Methods: In this in-vitro study, 80 extracted molar teeth were selected and randomly divided into three groups based on angle and radius of canal curvature. A 5 mm orthodontic wire was placed on the lateral surface of the root. Conventional radiographs were taken after insertion of endodontic file in the apical third of root canals. Radiographic images were scanned and imported to the software of CMOS digital system. Two observers estimated the file lengths with and without using calibration tool of digital measurement software. The correlation between observers was evaluated and then data were analyzed using Paired T-test with 95% confidence.
Results: Overall agreement between observers was good. There was no significant difference between the mean values of calibrated measurement and true file length in the basis of canal curves (P>0.001). However, there was significant difference between the mean values of uncalibrated measurement and true file length in the basis of canal curvature (P<0.001).
Conclusion: The calibrated measurement of file length was more accurate than that of the uncalibrated file length measurement.
Mehrdad Ghane, Seyed Jalal Pourhashemi, Ahmad Jafari, Hajar Shekarchizadeh,
Volume 29, Issue 1 (7-2016)
Abstract
Background and Aims: The aim of this study was to assess the oral health behaviors in women with addiction history.
Materials and Methods: A cross-sectional study was carried out in women drug treatment centers under the supervision of Welfare Organization of Tehran province in Iran. Data collection process was conducted in three centers including a questionnaire with an interview format, clinical examination, and Chi-Square test and MANOVA for statistical analysis.
Results: The mean age of 95 women participating in this study was less than forty, whereas the age of starting drugs was twenty two. A majority of the patients were unemployed (71%) and more than that of two-third did not have a diploma education. Almost half of dentate participants had never or rarely brushed their teeth. Most of them had never used dental floss, while more than half had three or more times snacks or sweet drinks and more than three-fourth were daily smokers. The MANOVA analysis showed that the type of clinic to be visited, age, used stimulant, drug dependency length, the last time a dentist being visited and the brushing period had a statistically significant relationship with Decayed Teeth (DT), Missing Teeth (MT) and Filled Teeth (FT) (P<0.05).
Conclusion: Women with the prior drug addiction history had an unpromising oral health status which was obvious in their self-perceived oral health. Taking the appropriate preventive and therapeutic actions aiming for promoting oral health status of them seems to be necessary.
Sara Koosha, Masoomeh Kandi Bidgoli, Azadeh Raouf, Reza Ezatian,
Volume 29, Issue 2 (11-2016)
Abstract
Background and Aims: Constant dynamic and static activities are considered as the main cause of musculoskeletal problems among dentists. The aim of this study was to evaluate the musculoskeletal problems and related factors among dentists in specialized clinics and dental schools in Tehran in 2014 using the REBA method.
Materials and Methods: In this cross-sectional study, the dentists from clinics of dental schools in Tehran were selected as individual targets. Nordic anddemopghrphic questionnaire were completed through interview from dentists. In order to assess the musculoskeletal disorders, REBA method (Rapid Entire Body Assessment) was used. In this method, positions and postures of the dentists during their work was observed and recorded. Data was analyzed using Regression Logestic test.
Results: The obtained results showed that among 100 dentist, 6% were in the very high risk (15-11) for musculoskeletal problems and 17% and 25% were in high-risk (10-8) and average risk (7-4), respectively. Based on the findings from Nordic questionnaire, the most skeletal- muscle travail were related to the neck (60%), lumbar (58%) and rear (46%) consequently. It seemed that factors such as gender, body mass index (BMI), height, specialty, body posture during the work (standing or sitting), smoking and using the direct or indirect vision, had an impact on the musculoskeletal disorders.
Conclusion: Findings from the final scoring of REBA showed that a high percentage of dentists were struggling with skeletal- muscle problems and they were in moderate to high range of risk for these type of disorders.