Comparative Evaluation of Fracture Resistance between Two Alumina Ceramic Copings
AhmadHasan
Ahangari
Assistant Professor, Dept of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
author
Kianoosh
Torabi
Associate Professor, Dept of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
author
Milad
Motamedi
Postgraduate Student, Dept of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences,
Shiraz, Iran.
author
Saeed
Salehi
Postgraduate Student, Dept of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences,
Shiraz, Iran.
author
text
article
2011
per
Introduction: In spite of ceramics’ desirable esthetics and compressive strength, they are inherently prone to fracture and are weak against tensile and torsional loads. In-Ceram Alumina is a type of reinforced alumina which has been used as a core material for crowns and three units anterior bidges since 90s. Turkom-Cera is presented in the market recently which uses a simple method to produce single and multiple unit anterior and posterior restorations. The purpose of this study is to evaluate the fracture resistance of copings made by these systems.
Materials & Methods: 40 brass dyes were prepared and divided into two groups. To make the copings, impression was taken and model dyes were made. 20 ceramic coping were prepared according to manufacturers instructions for each group, cemented to brass dyes and kept in 100% moisture for one week. Load to fracture test was performed by Universal testing machine and load was applied by a speed of 0.5 mm/min. Fracture load was recorded for each specimen. Data were collected and entered to the SPSS software and t-test was done.
Results: The average fracture load for Turkom-Cera was 1273 N and was 1079 N for In-Ceram Alumina. The maximum and minimum values for the first group was 2490, 530 N and for the second group was 1490, 714 N respectively. According to t-test results with P-value<0.05 there was no significant difference between the two groups.
Conclusion: According to the close results for both groups, clinical performance of the Turkom-Cera ceramic copings would be similar to In-Ceram Alumina and a wide range of clinical use could be anticioated for this system.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
147
156
https://jmds.mums.ac.ir/article_954_eac93056f0985054d26af071d591d2c5.pdf
dx.doi.org/10.22038/jmds.2011.954
Drug Therapy for Psychological Disorders of Patients with Lichen Planus: A Longitudinal Ordinal Study
Habibollah
Esmaeilli
Associate Professor, Dept of Biostatistics, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran
author
Mohamad-taghi
Shakeri
Associate Professor, Dept of Biostatistics, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran
author
Fatemeh
Salmani
MSC Biostatistics Student, Dept of Biostatistics, School of Health, Mashhad University of Medical Sciences,
Mashhad, Iran
author
Hadi
Jabari Noghabi
Assistant Professor, Dept of Statistics, School of Mathematical Sciences, Mashhad University of Ferdowsi,
Mashhad, Iran
author
Zohre
Dalirsani
Assistant Professor, Dept of Oral Medicine, School of Dentistry, Mashhad University of Medical Sciences,
Mashhad, Iran
author
text
article
2011
per
Introduction: In medical research, longitudinal studies are widely used to describe the disease process and effectiveness of treatment. In these studies individual outcomes are recorded in different sections. Many of the medical findings are characterized by ordinal scale. Because of the relationship between ordinal responses and the structure of longitudinal studies, special statistical methods are used. In this paper, we describe and compare different statistical methods, and recommend the most appropriate method to analyze the effect of drug therapy for psychologically disturbed patients with oral lichen planus..
Materials & Methods:In this study, the data of a clinical trial on 45 patients with oral lichen planus conducted in Mashhad Dental School was used. The outcome was defined as an ordinal scale using cumulative logit link function. Data was analyzed by fixed and random effects model.
Results: The results showed that random effect models were more accurate than the fixed effects model. Time and mental disorder showed significant effects on both the random effects model and fixed effects model. Treatment had no significant effect on random effects model; while it exhibited a significant effect on the fixed effects model.
Conclusion: To analyze longitudinal ordinal data, random effects model is recommended rather than fixed effect model.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
157
164
https://jmds.mums.ac.ir/article_955_9b8a5b4b3c7c3dd1a4e4a09edb677190.pdf
dx.doi.org/10.22038/jmds.2011.955
Evaluation of Stress Level and Related Factors among Students of Mashhad Dental School (Iran) in Academic Year of 2008-2009
Majid
Akbari
Assistant Professor, Dept of Restorative Dentistry, School of Dentistry, Mashhad University of Medical Sciences,
Mashhad, Iran
author
AmirHossein
Nejat
Undergraduate Student of Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
author
SeyedMehdi
Dastorani
Postgraduate Student of Endodontics, School of Dentistry, Yazd University of Medical Sciences, Yazd, Iran
author
Armita
Rouhani
Assistant Professor, Dept of Endodontics, School of Dentistry, Mashhad University of Medical Sciences,
Mashhad, Iran
author
text
article
2011
per
Introduction: Dental students are exposed to clinical environmental stresses in addition to educational environmental stresses. If psychological stressors become chronic and/or remain untreated, they result in psychological and physical symptoms. There are few studies about stress and dental students in our country. The aim of this study was to assess stress level and related factors sorted according to the academic year and gender, among dental students of Mashhad University of Medical Sciences during 2008-2009.
Materials & Methods: This study was a description-analytical and cross-sectional study. In this research two questionnaires were used concurrently and the information obtained was analyzed by the SPSS software.
Results: 52% of students showed abnormal levels of stress. Students of fourth academic year showed the highest level of stress. Stress levels in two genders were not significantly different. It was also characterized that university stressors played a more significant role in stress level than non-university stressors.
Conclusion: Based on the results of this study, and the findings of, high levels of stress among dental students as well as the harmfulness of high levels of stress, greater attentions must be given to this issue by the uthorities. Furthermore, the forth year students who have recently entered the clinic, are in the greatest need of help.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
165
176
https://jmds.mums.ac.ir/article_956_d5d3d8cd3b28dbb4c904ae5b12f98f95.pdf
dx.doi.org/10.22038/jmds.2011.956
Assessment of Incidence of Denture Hyperplasia Lesion in Biopsies Referred to Department Of Oral and Maxillofacial Pathology of Mashhad Dental School
Reza
Zare MahmoodAbadi
Assistant Professor, Dept of Oral & Maxillofacial Pathology, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
author
Shadi
Saghafi
Associate Professor, Dept of Oral & Maxillofacial Pathology, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
author
Parviz
Mahmoudi
Instructor, Dept of Oral & Maxillofacial Pathology, School of Dentistry, Mashhad University of Medical Sciences,
Mashhad, Iran
author
text
article
2011
per
Introduction: Complications resulting from removable denture consist of a wide range of oral mucosal lesions, the prevention of which and dealing with their complications are both the dentist’s and the patient’s responsibilities. The aim of this study was to evaluate the frequency of denture hyperplasia in Mashhad Dental School.
Materials & Methods: In this descriptive-cross sectional study, we aimed to assess the incidence of denture hyperplasia lesions on biopsies received in the Department of Pathology of Mashhad Dental School since 1357 till 1387 Collected data were statistically analyzed using the SPSS software and tables and diagrams were generated.
Results: The lesions results from denture were 5.6% of all lesions. From 462 cases, 368 cases occurred in women and 94 in men. In 97.8% of patients IFH and in 2.2% of patients IPH were found. In this study, IFH with 452 cases were observed more frequently in the female (79.7%) than the male subjects and in the 5th and 6th decades (68.2%). The common location of this lesion was mandible (69.9%) and anterior region (85.7%). Lesion enlargement (4.6%), Pain and burning (9%) sensation were recognized as the two most common referring factors to the dentist associated with these lesions.
Conclusion: In this study the IFH had the highest frequency and the IPH occurred only in a small percentage of lesions. Overall, the denture hyperplasia was more common in females in the 4th and 5th decades. The highest frequency of referring to the Dental School was between years 1367-1376 (54.9%).
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
177
184
https://jmds.mums.ac.ir/article_957_5442fe823fbcbc1c6492892ba2afd99a.pdf
dx.doi.org/10.22038/jmds.2011.957
Comparison of Two Bonding Systems: Self Etch Versus Etch and Rinse in Effectiveness of Fissure Sealants on Newly Erupted First Permanent Molars
Katayoun
Salem
Assistant Professor, Oral & Maxillofacial Pathology, Dental Research Center, School of Dentistry, Guilan University of Medical Sciences, Guilan, Iran
author
Fatemeh
Shahsavari
Assistant Professor, Oral & Maxillofacial Pathology, Islamic Azad University, Dental Branch, Tehran, Iran
author
Arash
Anisian
Assistant Professor, Dept of Epidemiology, School of Medical, Shahid Beheshti University of Medical Sciences,
Tehran, Iran
author
Mehran
Moradi
Dentist
author
text
article
2011
per
Introduction: Pit and fissures are the most common affected sites of caries occurance in newly erupted first permanent molars, however effectiveness of sealants are questionable in these teeth,due to difficulties in moisture control. The purpose of this study was to evaluate and compare the impact of two different categories of dentin bonding agents on sealant performance.
Materials & Methods: 56 pairs of sealants (122 teeth) were placed bilaterally and randomly on the occlusal surface of both upper and lower first molars with either dentin bonding agent. With no preparation of the surface, Adper prompt or Excite both were applied as one layer and cured before sealant placement. Caries assessment was performed according to the CCC method (Color, Coverage, Caries) introduced by Deery et al. (2001) at 6-month intervals for 12 months. Partially or totally lost sealants were replaced at each recall visit. Data were analyzed using the Wilcoxon test.
Results: Total etch and Excite were significantly superior in both retention and caries prevention (P=0.0001). Excite showed a significantly greater retention in the mandible than maxilla (P=0.027), whilst Adpaer prompt showed no difference between the jaws.. Among the teeth whose sealants were lost, progression of caries was greater in the Adper Prompt group.
Conclusion: According to findings of this study, application of total-etch and bond is preferred to self-etch adhesives before sealant application in newly erupted first permanent molars.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
185
194
https://jmds.mums.ac.ir/article_958_3dca7f104e5205e76fd27182080f2931.pdf
dx.doi.org/10.22038/jmds.2011.958
Level of Glycemic Control in Diabetic Patients Reffering to Zahedan Dental School (Iran) in 2005
Leila
FarhadMolashahi
Assistant Professor, Dept of Oral Medicine, School of Dentistry, Zahedan University of Medical Sciences, Zahedan, Iran
author
Hamideh
Kadeh
Assistant Professor, Dept of Oral & Maxillofacial Pathology, Zahedan University of Medical Sciences,
Zahedan, Iran
author
Shirin
Saravani
Assistant Professor, Dept of Oral & Maxillofacial Pathology, Zahedan University of Medical Sciences,
Zahedan, Iran
author
AliReza
Dashipoor
Instructor, Dept of Nutrition & Food Sciense, School of Medical, Zahedan University of Medical Sciences, Zahedan, Iran
author
text
article
2011
per
Introduction: Currently, diabetes is a basic problem in many countries. Increase in the prevalence of diabetes places dentists in the position of the first member of a health care team to detect new cases of diabetes. Besides, dentists must also be able to render dental care to patients who are already being treated for diabetes. Because of importance of glycemic control of diabetic patients in dental treatment plan and strong correlation between oral complications and level of glycemic control, the purpose of this study was to evaluate the level of glycemic control in diabetic dental patients before dental procedures.
Materials & Methods: At this cross sectional study, 100 diabetic patient's reffered to Oral Medicine Department of Zahedan Dental School, were studied (from May to March 2005). After an informed consent of diabetic patients, patient’s blood sample was taken in standard conditions, sent to laboratory to detect level of HbA1c and the level of glycemic control was determined in patients. Data were analyzed by the Chi-square, Mann-Whitney, Kruskal-Wallis and t-tests.
Results: Thirty two percent of patients had good glycemic control (6%≤HbA1c≤7.5%), 28% of patients had fair control (7.6%≤HbA1c≤8.9%) and 35% of them had poor control of diabetes (9%<HbA1c<20%). There were no significant correlations between age, sex, education, duration of disease and HbA1c level, but there was a significant association between medication type and HbA1c level (P=0.008).
Conclusion: Diabetic dental patients glycemic status may not be controlled at a desired level and dentists have to change dental treatment plan accordingly, thus attention should be paid to the glycemic control in diabetic dental patients before any procedure.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
195
204
https://jmds.mums.ac.ir/article_959_f1d9bae694f0f1c81686b421238c637c.pdf
dx.doi.org/10.22038/jmds.2011.959
A Survey of Microbial Contamination of New Acrylic Removable Denture's Made in
Yazd (Iran) Dental Laboratories 2009
MohammadHossein
LotfiKamran
Assistant Professor, Dept of Prosthodontics, School of Dentistry, Shahid Sadoughi University of Yazd Medical Sciences, Yazd, Iran
author
AbbasAli
JafariNodoushan
Associate Professor, Medical Mycologist, School of Medicine, Shahid Sadoughi University of Yazd Medical Sciences,
Yazd, Iran
author
Abbas
FalahTafti
Assistant Professor, Dept of Prosthodontics, School of Dentistry, Shahid Sadoughi University of Yazd Medical Sciences, Yazd, Iran
author
SeidSajjad
Mosavi
Dentist
author
Maryam
Sadah
Laboratory BS, Dept of Bacteriology & Parasitology, School of Medicine, Shahid Sadoughi University of Yazd Medical Sciences, Yazd, Iran
author
Marzieh
Modaresi
Laboratory BS, Dept of Bacteriology & Parasitology, School of Medicine, Shahid Sadoughi University of Yazd Medical Sciences, Yazd, Iran
author
text
article
2011
per
Introduction: Microbial contamination of removable denture and their contact with saliva and oral tissues can cause microbial cross-contamination among dental clinic personnel, dental laboratories and patients. These microorganisms can cause unpredictable infections especially systemic, pneumonia and even cardiac infections in elderly and immunosupressed patients. The aim of this study was to identify the microorganisms on the surface of removable prostheses ready for delivery (new dentures) in Yazd dental laboratories
Materials & Methods: Fifty five new removable complete dentures were randomly selected from 5 Yazd dental laboratories. All dentures were washed by 100ml of sterile normal saline, centrifuged and precipitants were used for culture on the specific microbial media. Finally, the isolated aerobic, anaerobic microbial colonies and isolated fungi were identified according to diagnostic tests.
Results: Bacterial contaminations were seen in all prostheses whereas 58.2% showed fungal contaminations. Staphylococcus, nonpathogenic Neisseria spp, Corynebacteria, Acenitobacteria, E. coli, and Entrobacter spp were the common isolated bacteria in the current study. Saprophyte fungi such as Aspergillus, penicillium, mucor and yeasts especially Candida species were the most isolated fungi from dental prostheses in the present study.
Conclusion: Results of the present study showed bacterial and fungal contamination even on newly made prostheses. It seems that control and prevention of cross-contamination should be taken more seriously in dental practices and laboratories.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
205
212
https://jmds.mums.ac.ir/article_960_a50863c6bd47c825758be54058da3959.pdf
dx.doi.org/10.22038/jmds.2011.960
Comparative Study of IL17 in Normal and Symptomatic Dental Pulps by Immunohistochemistry Technique
SeidBehrooz
Mousavi
Professor, Dept of Endodontics, School of dentistry, Isfahan University of Medical Sciences & Head of Professor Torabinegad Research Center, Isfahan, Iran
author
Parviz
Deyhimi
Associate Professor, Dept of Oral & Maxillofacial Pathology, School of dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
author
Mohammad
Hosinian
Postgraduate Student of Endodontics, School of dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
author
Alireza
Andalib
Assistant Professor, Dept of Immunology, School of Medical, Isfahan University of Medical Sciences, Isfahan, Iran
author
text
article
2011
per
Introduction: IL17 is a pro-inflammatory cytokine which is often produced from CD4+ Th17 cells and uncertainty exists about its protective or destructive function. One of destructive functions of IL17 is through acting on osteoclasts. The aim of this study was to evaluate IL17 protein expression in tissue obtained from normal and symptomatic dental pulps. Materials & Methods: Healthy dental pulp samples and irreversible dental pulp samples were obtained from 20 third molars and 20 carious molars respectively. After tissue processing, pulp samples were immunostained with IL17 antibodies. Thereafter, distribution and staining intensity of IL17 proteinwas evaluated by the SID score and findings were analyzed using the Mann-Whitney U test. Results: Analysing SID score with Mann-whitney test showed significant difference in IL17 (P=0.002) between symptomatic dental pulp tissues (2.35±1.23) and healthy samples (1.15±0.93). Conclusion: The results indicated that significantly a greater level of IL17 is found in pulps of symptomatic teeth than those of normal teeth. Therefore IL17 may be suggested as a pathologic marker of inflammatory function in irreversible pulpitis.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
213
222
https://jmds.mums.ac.ir/article_961_d6594ae3b13f1c1fd6895bd61744fa74.pdf
dx.doi.org/10.22038/jmds.2011.961
Pindborg Tumor. Review of Articles
Ataollah
Habibi
Associate Professor, Dep of Oral & Maxillofacial Surgery, School of Dentistry, Oral & Maxillofacial Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
author
text
article
2011
per
The present profile of the Pindborg Tumor or calcifying epithelial odontogenic tumour (CEOT) is based on a literature survey of 210 (193 intraosseous & 17 extraosseous) published tumour cases. The CEOT is a benign, though occasional locally invasive, slow-growing neoplasm occurring as intraosseous (95%) and extraosseous (5%) variants. 52% of intraosseous CEOT are associated with an unerupted tooth. CEOT shows a relative frequency of 1% all of odontogenic tumor. The extraosseous variant is diagnosed slightly earlier (mean age 34 years) than the intraosseous type (mean age 39 years). Both variants have an almost 1:1 gender ratio. The intraosseous CEOT shows a maxilla: mandible site ratio of 1:3 and are mainly located in the premolar/molar region. The present authors present evidence that the CEOT originates from the complex system of dental laminae or remnants.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
223
236
https://jmds.mums.ac.ir/article_962_f92ac295752341cfb800b59a933899bf.pdf
dx.doi.org/10.22038/jmds.2011.962
An Obturator-Eye Combination Prosthesis Using Magnets: A Clinical Report.
Jafar
Gharechahi
Professor, Dept of Prosthodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
author
AmirTaher
MirMortazavi
Postgraduate Student of Prosthodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
author
text
article
2011
per
Introduction: Rehabilitation of facial defect with an intraoral communication is a difficult challenge for the maxillofacial prosthodontist. The use of magnets is the most efficient means of providing combination prostheses with adequate retention and stability.
The aim of this report was to describe a simple method of fabricating an obturator-eye combination prosthesis using magnets.
Case Report: A 54-year-old edentulous female patient with the history of diabetes mellitus, hypertension and coronary bypass surgery was referred for definitive prosthetic rehabilitation 8 months after the surgical resection of a mucormycosis intraoral-facial combination defect. The patients underwent a partial left maxillectomy and left orbital exoneration which removed all adjacent tissues. Swallowing and mastication problems were experienced postoperatively, and the patient complained from her appearance. The proposed treatment plan included construction of a maxillary complete denture with a palatal obturator and a mandibular complete denture. Magnets were used to attach the oculopalpebral prosthesis to the maxillary obturator.
Conclusion: The prosthetic rehabilitation of a patient with a combined intraoral-extraoral defect was presented. Use of retention magnets retains denture and makes it stable and comfortable for the patient. This treatment improves oral function as well as esthetics.
Journal of Mashhad Dental School
Mashhad University of Medical Sciences, School of Dentistry
1560-9286
35
v.
3
no.
2011
237
242
https://jmds.mums.ac.ir/article_963_b98fcf18cc5cbfa6d6277e9194529faa.pdf
dx.doi.org/10.22038/jmds.2011.963