JOURNAL OF ISLAMIC DENTAL ASSOCIATION OF IRAN (MAJALLAH-I-DANDANPIZISHKI)
Year:2003 | Volume:15 | Issue:1 (44)|Papers Count:11

With regard to the importance of marginal adaptation of casting restorations on prepared teeth and effect of investing methods. This study evaluated the marginal gap of full casting crowns fabricated with "one layer wet ring liner" and "two layer wet ring liner". The study conducted experimentally 10 of the same wax patterns, immediately after refining margin on the metal die, were invested under each foretold investing method, using phosphate bonded investment (Accufit). Castings were produced using base metal alloy (Verabond). Marginal gap, of each casting, along four predetermined reference marks on the die, under stereoscopic microscope, were photographed by digital camera. "blind" operator performed the measurements in micron' using the scale of photoshop. Data were analyzed with Univariate ANOV A at P=0.05. Marginal gap (Mean±SD) of casting fabricated with the "one layer wet ring liner" was (46±32µm) and with the "two layer wet ring liner" was (50±28µm). For the marginal gap, casting fabricated with the "one layer wet ring liner" were not significantly (P =.654) different from those fabricated with the "two layer wet ring liner". Marginal gap showed no statistically significant (P > .05) difference, among along four reference marks in each investing method. Distribution of dispersion and inconsistency of casting fit showed no statistically significant (P =0.152) different between investing methods. "One or two layer wet ring liner" are desirable and reliable methods to fabricate dental castings with clinically acceptable marginal gap.  

Dental diseases in children have high prevalence the purpose of this study was to assess the effectiveness of oral health game on brushing skill and plaque score of school children. A Quasi-experimental study was carried on 220 subjects randomly and sampling was done on the fourth grade's girl students. A checklist was used to measuring the brushing skill and plaque score. t. test showed that there is a significant statistical difference between two groups brushing skill (P= 0.000) and plaque score (P= 0.000). The effectiveness of oral health game was 96.9% in brushing skill and the plaque score to 14.7%.  

The purpose of this study is to investigate the success and failure rates regarding the three levels of root canal obturation (Overfilled, Underfilled, Flushfilled), and the factors affecting them. 111 patient (1377-1379) with one of the 3 levels of obturated root canals, were examined clinically and radiographically after one year. Patients having a combination of: two or three obturated level, with apical perforation, having root or crown fracture, with no function, no coronal seal, Severe periodontal disease 'related to dental pulp, and also patients unavailable for following up were all excluded from the study. Of 29 flushfilled type 96.6% showed successful, 3.4% questionable results. Of 40 overfilled type 60% had successful results and 25% questionable results and 15% were failures. Of 42 underfilled types, 50% had successful results, 23.8% questionable results and 26.2% were failures. The findings revealed that the prognosis of treatment in the flushfilled root canal type was stronger; The same was true regarding the overfilled one, being superior over the underfilled type.    

Recognizing canal configuration is necessary for a correct endodontic therapy, and having no information about canal configuration causes failure in therapy. Since one of the most effective factors in canal configuration is race, we decided to have a laboratory and clinical research in Isfahan. The aim is to recognize canal co figuration of the maxillary second premolar and compare the clinical and laboratory results. 1- Laboratory study (In vitro): 105 maxillary second Premolar were selated then .we disinfected them in CLONA 5.25%. We made a correct access cavity on the teeth. In order vacute the pulp tissue in chamber and canals, we placed them in H2O2 35% for 15 days. and HN03 5% for 3 days to be decalcified. Then we used 70%, 90%, 100% isopropyl a1chole to dehidrate the teeth. After the above processes we injected India ink in - 1.8 P, in canals and canal configuration. Clinical study (In vivo): In this study we selected 132 maxillary second premolar treated in graduate and under graduate departments of Isfahan University school of dentistry. Then we studied every radiograph using a negatoscope, the results were analyzed the data. 1-laboratory (In vitro) results: Out of 105 maxillary second Premolar (researchable), 30 type 1(28.6%),13 type II (12.4%), 48 type III (45.7%), 12 type IV (11.4%) also 2 with three canal (1.9%) were out of Weine classification. 2- Clinical (In vivo) Results: Out of 132 maxillary second premolar, 82 type I (62.13%), 21 type 11 (15.91%), 25 type III (18.92%), 4 type IV (3.04%) in this study don't observe three canals. The outcoming results of this study are different from other researches. Perhaps the differences are caused by some factors such as race and method. Also the clinical results are too different from laboratory results and it is because of method. The laboratory study is more prease.      

The objective of this research was to determine the incidence of oral lesions in patients psoriasis in Loghman-Hakim hospital Tehran In 2002. This is a descriptive survey. The study was made on 100 consecutive patients with the clinical diagnosis of psoriasis from the department of dermatology of Loghman- Hakim hospital and these were examined clinically and interviewed. After collecting cases history and performing clinical examinations, information questionnaire forms were collected. The incidence of oral lesions in patients were determined and actual frequency of them with 95% possibility in community was evaluated. Also, effect of associated factors with the incidence of lesions was assessed. Of the 100 patients, 52 were males 48 were females with mean age of 38±17 years. The mean duration of the disease was 10.5 years 49% of patients had oral lesions including 46% fissured tongue, 16% geographic tongue and 4% ectopic geographic tongue. Age, sex, systemic disease and smoking had not a significant relationship with the incidence of oral lesions. 39. 2% of patients without oral lesions and 57. 1% of ones with oral lesions had increased stress and anxiety (p<0.07). Incidence of fissured tongue, geographic tongue and ectopic geographic tongue significantly increased in the patients with psoriasis in view of the high incidence of oral lesions and their comliances.      

Maxillofacial trauma is a common cause of dental injuries and this study with the aim of evaluation of dental injuries prevalence in patients who refer to dentistry department of medicolegal organization would be done. In this cross sectional study, 400 persons who referred to dentistry department of medicolegal organization were being examed from May to October 2002 and after data collection and analysis by SPSS software these results was obtained: About 20% of persons were female and 80% were male. The mean age was 30 and involvement of anterior and maxillary teeth were more than posterior and mandibular teeth. Luxation of teeth was occurred more than other injuries. In most of the cases one tooth was involved. The most common causes of these injuries was assault and car accidents were the second one. Periodontal problems and the dental carries were the most common causes that increased the susceptibility of the teeth to trauma. 18,5% of injuries were non traumatic (patients claimed they were traumatic) and 74,4% were traumatic. Most of nontraumatic injuries were displacement and avulsion and such injuries were obviously more in female than male. Results of our study was almost similar to medicolegal studies in other countries. Frontal teeth are prone to traumatic injuries specially in assault and car accident.  

The presence of remained caries under restorations that can not be seen has always been a problem for dentists and can follow by recurrence of caries and failure of the restoration. The aim of this study is to comprise the ability of probe and a caries detector dye in diagnosis of remained caries of dental cavities, prepared in Pediatric department of Kerman dental university. This cross sectional study has been carried out in 100 prepared dental cavities and by use of sable seek, a caries detector dye. After testing the cavities by probe and finding no remained caries, the caries detector dye was applied, be washed and then caries presentation was being assessed by recording stained or non stained areas in dentin. Also the correlation between type of teeth jaw number of teeth and type of cavities, with staining has been assessed, and chi-square test has been used for assessing. According to this research 66% of prepared cavities were stained. 36% of the cavities were in primary teeth and 64% in permanent ones. The most permanent tooth in this research was number 6 and the most staining was in E (88.9%). 66% of the cavities, those showed no caries by probe, were stained by the caries detector dye. There was a statistically significant difference between type of teeth (primary or permanent) and staining, and the primary teeth showed more staining than permanent ones.  

The practice of restorative dentistry has changed dramatically with the introduction of innovative technique and materials. Adhesive resin systems are examples of these materials that have led to the popularity of bonded ceramics and resin-retained fixed partial dentures. Many researches have been performed to increase bond strength of adhesive material to dental structures and metal surfaces. The main goals in bonding systems are: retention, elimination or reduction of microleakage and reinforcement of the remaining tooth structures. The present article is a systematic review of researches on adhesive resin systems, from 1980-2002, which have been founded in Medline.      

Histologic grading of malignant tumors has been used for many decades but its prognostic value is still controversial. The aim of this article is the evaluation of different grading systems and their prognostic significance in oral SCC. Several histopathologic classifications were compared with advantages and indications of each, presented. The best and most practical system was introduced. Based on the recent studies, classification of tumors according to the differentiation or degree of Keratinization alone has a limited prognostic value in oral SCC. Where as, grading systems based on the evaluation of different histological parameters (multifactorial grading systems) show significant relation with lymph node metastasis and prognosis. In addition, like most human neoplasms, oral SCCs consist of heterogeneous cell populations with variable degree of differentiation and biological behavior. Thus, histologic grading of the deep invasive tumor margins has the most important and significant prognostic value in oral SCC. Today, this method is routinely. used in various studies on oral SCC.