Journal of Research in Dental Sciences
Year:2008 | Volume:5 | Issue:3|Papers Count:8

Background and Purpose: Since this research project is a descriptive study and is an applied study, it can be helpful to analytical considerations in this respect. There is a dearth of research on this topic, therefore, few comprehensive studies exist in our chosen domain and the need for further studies of this type are clearly felt. In addition to providing information on the present condition of the number of files and cases of complaints in medical legislation, this study can illuminate the scope of medical law and the responsibility of the medical doctors.Materials and Methods: The researcher went to the center of Medical litigation in Tehran province and examined the complaints of the patients from 2003-2007. She made a comprehensive study of the files and considered the complaints made against dentists in the processes of surgery. The data obtained were then analyze and scrutinized.Findings: Among the 57 files which from 2003-2007were opened in treatment of surgery of jaw and mouth in Tehran's Medical legislation. Most complaints (%84) were about male dentists, %12/3 of which were because of fractures in jaw, %10/5 were about numbness of jaw, %7 were because of opening in sinus, %5/3 were because of entering the tooth into the sinus, %12/3 were because of the infection of jaw, %21/1 because of the mistaken excavation of the tooth, %8/8 were because of not preparing the radiographic, %3/5 were because of post-surgery bleeding, %7 were because of harm to the adjacent tooth, %5/3 were because of breaking tuberosity, %14 were because of pains after tooth excavation, and finally%8/8 were because of implant break. According to Medical legislation's report in 33 percents of the cases, the dentists were. cleared of the charges and in%67 they became convicted.Conclusion: According to reports received from the Legal Medicine Institution, there has Been an increase in individuals' referring in order to attend to the referees' problems and in treatment dissatisfaction in recent years. The most interesting and the most challenging decisions of Commissions was that in approximately one third of cases that the upper molar tooth entered the jaw sinus space when being pulled, the dentist has been acquitted and in about%85 of cases anesthesia has resulted in dentist's conviction which it seems controversial scientifically. Also, about%84 of cases of jaw fracture and jaw anesthesia resulted from the fault of dentist, lack of expertise and experience, and choosing patient incorrectly. It is worthy to note that most of jaw fractures and jaw anesthesia had occurred in Mandible. In case of existence of pain after pulling the tooth, the probability of conviction is zero.

Background and Aim: Three Dimensional obturation of root canal to preserve or reach the regeneration or healing of periodontal tissues is one of main goals of root canal therapy. Root end filling materials are used in numerous situations to reach the above goals. One of the common root end- filling materials is mineral trioxide aggregate which the foreign one is more expensive than Iranian one. The aim of this study was to compare the reaction of connective tissue to Iranian and foreign MTA.Materials and Methods: 40 rats were divided in to 5 groups of 8. The polyethylene tubes filled whit foreign and Iran made white MTA and also empty ones were implanted in subcutaneous connective tissue. The samples were examined histological after 7, 14, 30, 60 and 90 days and were scored as followings: 0, without inflammatory cells; without inflammatory reaction.1, less than 25 inflammatory cells; mild inflammatory reaction.2, 25 to 125 inflammatory cells; moderate inflammatory reaction.3, more than 125 inflammatory cells; severe inflammatory reaction. The samples were prepared for XRD test under (20- 120) X), and select major peak for comparisons. Kruskal-Wallis test with a significance level of p<0.05 was used to compare statistical differences.Results: Overall, inflammatory reactions were reduced in all groups gradually.Experimental groups had moderate to severe inflammation in 7 days interval which had significant difference with the control group having mild to moderate inflammation (p=0.04).). There was significant differences between Before and after exposure it seems that one biphasic calcium phosphate layer (derived from substrate), be generated also There was not any significant differences between experimental and control group in 14, 30, 60, 90 days (p>0.05).Conclusion: Inflammatory tissue reaction to subcutaneous implantation of Iranian and foreign MTA was the same.

Background and aim: Dental irreversible hydrocolloid (Alginate) is a major dental used world wide in many clinical procedures. The purpose of this study was to investingate the dimensional stability after prolonged storage of Alginate Elastic Chromo. This study was carried out in 2008 in Azad Islamic university.Method and Material: This experimental study was carried out by using labratory metal master model that contained two dies.20 impression were taken for master model by Alginate Elastic Chromo The four storage conditions were as follow: 0/5 hours, 24 hours , 48 hours, 120 hours, stone model were poured. Die's height, diameter and distance between dies were measured by profile projector and compared with labratory model by use ANOVA test.Results: There is no significant different between of four times casting. Height & distance dimensional change were less than 1/5% (Max distoration after 24 hours) but diameters were more than 1/5%.Conclusion: Alginate Elastic Chromo was not dimensionally stable over a 5 day period ( 120 hours). However, no effect of the times on dimensional change.

Background and aim: One of the dentists' problems is the identification of proximal caries. B.W. radiograph is the most traditional method that is used in proximal caries detection. Another method can be used caries identification (especially in proximal caries) is the using of digital system that carry out by traditional scanner& digital camera. Its aim in vitro study was the comparison between the diagnostic power of conventional and digitized radiographs in detecting proximal caries.Methods and Materials: 40 extracted molars were selected. Cavities were prepared by 1/2 round bur D& Z under contact point. Then cavities were become deeper and larger by 1, 2, 3 & 4 round burs on 40 proximal surfaces of dentals. B.W. radiographs were taken and digitized by a digital camera"DSC-W200Sony cyber- Shot with 6, 9, 12 Mp. The conventional and digitized radiographs were observed by 4 experienced radiologists.Results: The mean of sensitivity in B.W. method is 97.5%, the mean of specificity is 91.25%, in detection by digital camera with resolution 6Mp the mean of sensitivity is 98.125%, the mean of specificity is 88.75%, with resolution9Mp the mean of sensitivity and specificity are 95.75%, 91.25% respectively; with resolution 12Mp, the mean of sensitivity and specificity are 98.75%, 92.5%. No significant differences were showed between them.Conclusion: This study showed, digital camera can be used for digitizing conventional radiographs, saving in computer, observing when ever and sending to a far place.

Background and aim: Pemphigus vulgaris is a mucocutanous disease with a prevalence of 1% to 5% was reported. It includes2% of oral erosive lesions.The most common sites of oral lesions are soft palate, buccal mucosa, labial mucosa, and gingiva. Painful oral lesions interfere with oral hygiene and lead to increased susceptibility to periodontal disease. long term use of immunosuppressive drugs, on the other hand, can increase periodontal disease susceptibility.Material and methods: In this case report study, a 42 years female who has had oral Pemphigus vulgaris for 9 years and was under treatment was, referred for treatment of generalized aggressive periodontitis. The medical history, complications, periodontal findings, diagnosis, treatment plan and periodontal prognosis One mentioned.

Background and aim: According to the frequent tooth loss at molar sites and necessity to replace them, the purpose of this study was to evaluate the short term clinical and radiographic outcomes of fresh molar sockets immediately implanted, with tapered wide platform implants.Materials and Methods: 10 patients with the mean age of 46 were treated with the immediate implantation of 12 wide diameter and wide platform implants in the molar sites.Following the atraumatic extraction of molars and preservation of the interradicular septum, implantswere placed. Immediately after the insertion of healing abutment, implant primary stability was tested with the Periotest and the crestal bone level was estimated with the periapical long-cone radiographs.Four months later patients were recalled for final evaluations, the crestal bone loss was measured and the periotest values were judged with the Wilcoxon test.Results: All 12 implants were reported with no pain, infection and continuous radiographic lucency.The average PTV1 and PTV2 reported were -4.9±0.99 and -4.6±1.37 (-2 to -7).The difference between PTVs wasn' t statistically significant (P>0.05).The average crestal bone loss was 0.54±0.96.Conclusion: Successful results were achieved with wide diameter and wide platform implants with the appropriate case selection and surgical technique.

Background and aim: Marginal integrity in all ceramic restorations is one of the important element of the success rate. Whether, there was not favourable marginal integrity between tooth margin and crown, it caused gingival inflammation and caries recurrence. according to the importance of design preparation in the marginal integrity, in this study decided to assess the marginal integrity between 2 different type of the marginal preparation: shoulder and heavy chamfer, at Azad university, school of dentistry in 2008.Methods & material: This experimental research has been done in vitro with the single blind technique. one standard die with 7mm height, 5mm diameter was prepared by the milling machine. the preparation design consists half shoulder 90 degree & in the other half heavy chamfer, whit 1mm depth in both of them. and then crowns were made of IPS e.max press & after cementation, were ground at the buccolingually direction. then they were coated by gold & observed under SEM.Results: Marginal gap in shoulder preparation was 16/42±1/904 & in heavy chamfer site was 19±1/054.Conclusion: The marginal gap in the shoulder preparation was less than heavy chamfer preparation.

Background and aim: With the advent of increased orthodontic treatment for adult patients and the increasing use of esthetic brackets, the importance of researches regarding microorganism msadherence to these brackets are emphasized. The aim of this study was to determine the influence of different orthodontic bracket materials (metal & ceramic) on growth & adherence of Streptococcus mutans & Candida albicans.Materials and Methods: This experimental invitro study was accomplished on 72 specimens. Two types of brackets from the premolars were used: metallic and ceramic.Streptococcus mutans and Candida albicans and the association of both were studied.Small plates containing noutrient broth medium with 20% sucrose added were inoculated with each of the microbial suspensions. The brackets were placed in the plates. The samples were incubated at 37°C for 5 days. After that the brackets and the supernatant were removed from the plates and the colony forming units (CFUs) adhering to the glass were counted macroscopically. some of the brackets were studied with electron microscopy.Results: The study was accomplished on 72 specimens. The adherence of microorganisms was decreased by the. Metallic brackets and increased by the ceramic ones (p<0.001).study with electron microscopy shows the same results.Conclusion: The growth & adherence capacity of Streptococcus mutans & Candida albicans is different in the presence of various orthodontic bracket materials. Therefore we propose that the use of metallic brackets may be useful in a particular group of patients with a risk of candida albicans infection, such as patients with diabetes or immunosuppressive states and also when decrease in caries risk and periodontal disease is considered.