فهرست مطالب

Avicenna Journal of Dental Research
Volume:5 Issue: 1, Jun 2013

  • تاریخ انتشار: 1392/12/25
  • تعداد عناوین: 7
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  • Seyed Javad Kia, Arash Mansourian *, Masoumeh Nikkhah, Nariman Nikparto, Najmeh Shanbezadeh Page 1
    Background
    Lichen planus is a disease with unknown etiology that affects the skin and the mucous membranes. Immune dysregulation in the pathogenesis of oral lichen planus (OLP) is well-known phenomenon..
    Objectives
    In this study, we compared the levels of the peripheral blood T lymphocytes between patients with OLP and control group..Patients and
    Methods
    In this study, 32 and 16 patients respectively with and without OLP were recruited. Five milliliters of the participants'' peripheral venous blood was drew in an EDTA-containing test tube and the levels of CD3+, CD4+, and CD8+ cells, CD4+/CD8+ and CD4+/CD3+ ratio were measured by means of two-color flow cytometry. The data were analyzed in SPPS v.19 by employing Mann-Whitney U test..
    Results
    There were no significant difference among the levels of CD3+, CD4+, and CD8+ lymphocytes and the ratio of CD4+/CD8+ and CD4+/CD3+ lymphocytes between patients and control group; however, there was a significant difference between male and female patients with respect to the levels of CD3+ and CD4+ lymphocytes and the ratio of CD4+/CD8+ and CD4+/CD3+ lymphocytes..
    Conclusions
    Our results confirm that only local immune mechanism known as skin-associated lymphoid tissue, not a systemic immunologic disorder, was involved in the OLP..
    Keywords: Lichen Planus, T, Lymphocytes, Peripheral Blood
  • Ebrahim Yarmohammadi, Mina Jazayeri, Zahra Khamverdi, Shahin Kasraei, Loghman Rezaei-Soufi * Page 2
    Background
    Teaching and educating students is one of the most important responsibilities of teachers. Polling from students is an important method to determine indicators for effective teaching..
    Objectives
    The purpose of the current study was to determine indicators of effective teaching from the point of view of dental students of the Dental Faculty of Hamadan University of Medical Sciences..
    Materials And Methods
    In this Cross-sectional study, there were 205 student participants from the dental faculty of Hamadan University of Medical Sciences. The valid and reliable researcher made questionnaire consisted of individual characteristics, teaching methods, knowledge and the power of communication. Data were analyzed by descriptive methods using the statistical package for social sciences (SPSS) v.13..
    Results
    In the field of knowledge, teaching method, power of communication and individual characteristics the priorities were subject predomination with average of 1.52, clear transmission with the average of 1.80, fair assessment with the average of 4.12 and fluent explanation with the average of 3.42, respectively..
    Conclusions
    Based on the students perspective, the most important aspect of effective teaching was teaching method. Having the ability in the subject clear transmission, being fair and clear communication were the priorities in each aspect..
    Keywords: Dentistry, Medical Education, Dental Students, Teaching Method
  • Masoumeh Khoshhal, Nazli Rabienejad, Abbas Shokri, Ali Heidari, Fariborz Vafae * Page 3
    Introduction
    McCune-Albright syndrome is a rare disease, characterized by triad of cafe-au-lait spots, endocrinopathies and fibrous dysplasia. These bone lesions are usually revealed during the first decade of life, together with pain, pathological fractures and secondary deformities..
    Case Presentation
    A 40-year-old female patient presented an opaque lesion at the left mandibular side of face, in a cone-beam computerized tomography (CBCT) view, during the implant placement evaluations. The patient had experienced precocious puberty and had undergone hysterectomy. Unilateral cafe-au-lait spots were present on patient’s left side of the face. There was no expansion in intraoral examination. The oral mucosa was also normal. No asymmetry was detected. The analysis of sample histopathology confirmed fibrous dysplasia..
    Conclusions
    In this patient we preferred following up. Afterwards, total surgical lesion resection can be performed. After a long-term follow-up, the area may receive an implant..
    Keywords: Cone, Beam CT, Dental Implant, McCune, Albright Syndrome
  • Parviz Torkzaban, Janet Moradi Haghgoo, Massoumeh Khoshhal, Syed Reza Arabi, Shilan Razaghi * Page 4
    Context: A key determinant for clinical success is the diagnosis of the bone density in a potential implant site. The percentage of bone-implant contact is related to bone density, and the axial stress contours around an implant are affected by the density of bone..Evidence Acquisition: A number of reports have emphasized the importance of the quality of bone on the survival of dental implants. The volume and density of the recipient bone have also been shown to be determining criteria to establish proper treatment plans with adequate number of implants and sufficient surface area. Previous clinical reports that did not alter the protocol of treatment related to bone density had variable survival rates. To the contrary, altering the treatment plan to compensate for soft bone types has provided similar survival rates in all bone densities..
    Results
    When bone density decreases and bone become softer, the implant surface in contact with the bone decreases, therefore treatment plan should be modified by changing the drilling protocol, using gradual loading and reducing the force on the prosthesis or increasing the loading area with increasing implant number, implant position, implant size, implant design (deeper and more threads with more pitch, squared shape) and implant body surface condition..
    Conclusions
    Once the prosthetic option, key implant position, and patient force factors have been determined, the bone density in the implant sites should be evaluated to modify the treatment plan. Inappropriate implant number or design in poor quality bone results in higher failure rates. Changing the treatment plan and implant design is suggested, based on bone density to achieve higher survival rates..
    Keywords: Bone Density, Dental Implant, Implant Design
  • Bijan Heidari, Fariborz Vafaei, Alireza Izadi, Amir Saleh, Zahra Dehbani, Sara Khazaei * Page 5
    Background
    Numerous factors have an effect on the accuracy of an impression and resultant cast, and these include: impression material, impression technique, tray selection, impression disinfection, storage time of impression before pouring, stone type used for fabrication of cast. Up to now, there has been little research conducted on the effect of contact time of acast with an impression, on the dimensional stability of a cast..
    Objectives
    The purpose of this study was to evaluate the effect of the contact time of silicone impression materials with stone casts, on the dimensional stability of resultant casts..
    Materials And Methods
    A total of 44 impressions were made from a stainless steel master model, with each one of two silicone impression materials (Elite HD+ and Speedex), and poured with Elite Master Type IV. The thickness of the light-body material (1 mm) was provided by using four copings. The resulting casts from each material were placed in four groups(n = 11) after each contact time with the impression (1 hour, 24 hours, 48 hours, 1 week). Distance between anterior and posterior abutments was measured for the casts and master model. Data were analyzed by two-way analysis of variance and a Tukey’s test..
    Results
    The relationship between the dimensional stability of the casts and the simultaneous effect of the impression material and contact time of the cast with the impression was not statistically significant (P = 0.099). Type of impression material on the dimensional stability of the cast had no significant effect (P = 0.163). Increased contact time of the cast with the impression resultedin increased dimensional change (P < 0.001)..
    Conclusions
    Dimensional stability of the casts after different contact time with the impression was acceptable. The best time to separate the cast from the impression was one hour after pouring the impression..
    Keywords: president, silicone impression material, Calcium Sulfate, Dental Cast
  • Mohammad Reza Jamalpour *, Ide Talimkhani Page 6
    Background
    In spite of common usage of the inferior alveolar nerve block (IANB), this method has some well-defined restrictions..
    Objectives
    The purpose of the present study was to compare these two techniques for the surgical removal of impacted lower third molars..Patients and
    Methods
    A total of 44 similarly impacted lower third molars (22 patients with two similar teeth) were selected. In each patient, one side was anesthetized with the Gow-Gates technique and another side with the IANB, randomly. The number of injections for achieving anesthesia, incidence of pain during injections, and the supplementary injections during surgery were recorded for each side.
    Results
    In Gow-Gates technique, less repetition of injection was required to achieve anesthesia as well as less supplementary injections during surgery; however, these differences were not significant statistically (P = 0.39, P = 0.11). The pain during Gow-Gates injections was significantly shorter than that of the IANB (P = 0.007)..
    Conclusions
    Even though the patients felt less pain during the Gow-Gates injection, this technique has no advantage over the IANB during surgical removal of impacted lower third molar..
    Keywords: Local Anesthesia, Mandibular Nerve, Inferior Alveolar Nerve
  • Farhad Faramarzi, Shahriar Shahriari, Abbas Shokri, Mitra Vossoghi *, Ghafar Yaghoobi Page 7
    Background
    Root and canal morphology of teeth has a significant role in endodontic treatment success. Third molars have strategic roles after losing first and second molars..
    Objectives
    This study investigated the morphology of permanent third molar using radiography in Dentistry University of Hamedan during 2011..
    Materials And Methods
    In this experimental study, 352 extracted molars (179 maxillary and 173 mandibular molars) were collected. After preparing access cavity and file placement in canals, to investigate the number of roots, canals and canal type periapical radiographies were taken from two directions (mesiodistal and buccolingual). The results were analyzed using SPSS version 16.0 software and descriptive statistics..
    Results
    According to the study on 173 mandibular third molars, 92.4%, 4.6%, and 2.89% had two, one, and three roots, respectively. Majority of them had two or three canals and most of mesial root canals were type 2; but in 179 maxillary third molars, findings showed that 67.6%, 15%, 11.7%, and 5.6% of teeth had three, one, two, and four roots, respectively, majority of which had three canals (68.7%). Canals of 100% of distobuccal and palatal roots and 91% of mesiobuccal roots were type 1..
    Conclusions
    However, root and canal anatomies of third molar teeth are unknown, but studies focusing on third molar teeth have shown their possibility of treatment..
    Keywords: Root Canal, Molar, Third, Mandible, Maxilla