JOURNAL OF ISLAMIC DENTAL ASSOCIATION OF IRAN (MAJALLAH-I-DANDANPIZISHKI)
Year:2004 | Volume:15 | Issue:4 (47)|Papers Count:13

Post retention in endodontically treated teeth is an important factor in post-core technique. One of the factors effective in post retention is the type of applied luting cement. The goal of this study was to compare the tensile strength of 3 luting cemnts: zinc phosphate, glass ionomer and Core max II in the retention of custom posts.In this study, 33 extracted maxillary central incisors, of the similar dimensions, were selected and divided into three groups randomly.All the teeth crowns were cut at 2 mm above CEJ. Following standard root canal therapy, 2/3 of the canal space was enlarged with pizo reamer No 2 and 3. The length of posts were 12 mm.Acrylic resin patterns, of the same dimensions, were made for all samples. In order to do the tensile strength test, a hole with the diameter of 2 mm was prepared on the crown of each tooth. Castings were Post retention in endodontically treated teeth is an important factor in post-core technique. One of the factors effective in post retention is the type of applied luting cement. The goal of this study was to compare the tensile strength of 3 luting cemnts: zinc phosphate, glass ionomer and Core max II in the retention of custom posts.In this study, 33 extracted maxillary central incisors, of the similar dimensions, were selected and divided into three groups randomly.All the teeth crowns were cut at 2 mm above CEJ. Following standard root canal therapy, 2/3 of the canal space was enlarged with pizo reamer No 2 and 3. The length of posts were 12 mm.Acrylic resin patterns, of the same dimensions, were made for all samples. In order to do the tensile strength test, a hole with the diameter of 2 mm was prepared on the crown of each tooth. Castings were fabricated using silver cast alloy, Then each group was cemented with one of the studied cements. Following cementation, the tensile strength of posts was measured using the instron testing machine. In order to analyze the data, using SPSS software, one-way variance analysis test was used and for paried comparisons t-student test was used (P= 0.05). No statistically significant differences were found in the tensile strength of glass ionomer (29.11 kg) and zinc phosphate (29.19kg) (P=0.97), whereas both of these cements showed significantly higher tensile strength than Core maxi (11-56Kg) (P =0.000).It is concluded that the retention of posts luted with glass ionomer and zinc phosphate are higher than Core max II.

The aim of the present study was to investigate the effects of dental factors causing maxillary sinusitis in order to help the dentists to prevent it, to overcome the probable side effects and in some cases to provide and early dental treatment.In this study, which reviewed the records of the patients affected with maxillary sinusitis during the last ten years, the predisposing factors were divided into dental and non-dental origins.The whole records of maxillary sinusitis were estimated as 158, from among than 29 patients had dental origin (18.35%). Another finding-of the present study was the predominance of male patients (68-96%) against females. The most cases of odontogenic maxillary sinusitis were in their fourth decade of life. 86.2% of the odontogenic maxillary sinusitis was caused by iatrogenic factors which were attributed mostly to the first maxillary molar.Amir Aalam hospital is Tehran's E.N.T hospital. In this study, conducted in the mentioned hospital, 158 records of patients with maxillary sinusitis were investigated and infections of dental origin were found as the reason of their return. The samples under study consisted of dental in fections, false root canal therapy and odontogenic cysts.

Surgical therapies combined with topical or systemic antibiotic administration have recently become popular for the treatment of patients with localized aggressive periodontitis (LAP). The goal of the present study was to investigate the clinical effects of Biostite combined with Tetracycline in angular defects of molar teeth among patients with LAP, as compared with debridement method in the control group. Four patients, referred to the periodontics department, with bilateral defects in both jaws were selected each patient had two experimental regions and two control ones, totally, 16 regions were in vest gated (8 experimental and 8 controls).Surgical operations were of full-thickness flap cy and crescent incision. In the experimental group, Biostite mixed with Tetracycline solution was placed on the defects whereas the control samples were just debrided.Clinical indices were measured at three stages: Phase 1 (pre-operation), the first operation and recently operation (6 months later). To do the statfistical analysis paired - Sample Hest was used. The results revealed that pocket depth indices, before the first and the second operations, were not statistically significant in the test group, as compared with the control group (P>0.05). The level of attachment and Loe sillness plaque index did not show any significant difference (P>0.05). The amount of bone fill in both groups revealed a significant differencian the second operation comparing to the first one (P > 0.05), however, this index was similar in both groups. Bone crest recession in the test group was 0.69 and that of control was 1 which the difference was not significant Thus, it is concluded that Biostite application combined with Tetracycline does not make any significant difference, as compared with debridement technique which may be attributed to the complete hygiene observation in both groups.

Tooth extraction, for any reasons, puts negative mentally and spiritually effects on the individuals. Additionally it leads to disorders in mastication, esthetics and speech. The high rate of tooth loss among adults and adolescents have stimulated the investigators to embark on this research.The purpose of this investigation was to determine the prevalence and reasons of tooth extraction among (15-18)-year-old students in Mashhad generally and according to sex.In this cross - sectional study, the applied techniques consisted of direct observation, question and in doublful cases OPG. A total number of 906 high school students (416 females and 490 males) with the age ranging from the aim of the present study was to investigate the effects of dental 15-18 years old were selected from seven education districts of the city of Mashhad in a random cluster sampling method. Totally, 25368 teeth were evaluated. Statistical analysis was performed with SPSS of district data test, using fisher exact test in two by two cross tabulation, Chi-square test and likelihood - ratio stafic in cross tabulation for comparing. The findings were as follows:1- The total missing teeth due to extraction were 209 in the population, 125(60%) teeth in boys and 84 (40%) in girls. The differences between them were not significant (P=0.86) 2- The total extracted teeth in the upper arch was 39% and that of the lower arch was 61% (P=0.001).3- In the upper arch, 20% of the extracted teeth were in boys and 19% were in girls (P=0.530).4- In the lower arch, 40% of the extracted teeth were in boys and 21% were in girls (P=0.08).5- Extracted teeth in the upper arch in boys were 20% and in the lower arch were 40.2% (P=0.000).6- Extracted teeth in the upper arch in girls were 20% and in the lower arch were 21% (P=0.661).7- The number of the extracted teeth in the right side was (54.5%) 114 and that of the left side was 95 (45.5%) (P=0.187).8- The Frequency of the extracted teeth was as follows: First molars (61%), First premolars (29%), second premolars (4.5%), Laterals (2-4%), canines (1.4%) and centrals (1.4%).9- The total extracted anterior teeth were 11 (5.2%), 9 teeth in boys and 2 in girls (P.V =0.005). Extracted posterior teeth were 94.8% that were nine times more than the anterior teeth.10- The extraction of the posterior teeth was due to caries and that of the anterior teeth were due to trauma, crowding and malposition.11- The extraction of the anterior teeth in boys were 4.5 times more than girls. Based on the findings of this investigation, the following conclusions drawn:Tooth extraction in boys were more than girls, extracted teeth in the lower arch were more than the upper, extracted teeth in the right side was more than the left side. Extraction of the posterior teeth was 19 times more than the anterior teeth because of the severe caries and the extraction of the anterior teeth were mainly due to trauma, crowding and malposition.Extraction of the anterior teeth in boy was 4.5 times more than the girls. The most extracted tooth was the first molar that in the lower jaw was twice of the upper jaw.

The purpose of this study was to investigate and compare the inhibitory factors involved in the non-urgency consultation with the dentist. This cross-sectional study was conducted on 200 people of Tehran citizens (109 females and 91 males) with the mean age of 35 Years, by phone - calls. The information about the last systemic consultation, the reasons for non-consultation and the amount of fear about dentistry practices were considered significantly important and the knowledge about age, sex, level of education and smoking were considered as minor ones.The results showed that the average of non-urgency consultation for males was 265 days and that of females was 118 days. The most important inhibitory factor, in the non-urgency consultation, was their lack of need for dental visits. Time shortage and expensive costs were ranked as other factors (41.3% and 28.2%, respectively). Lack of confidence about infection control and asepsis were found to be the weakest inhibitory factors (18% among females and 4.4% among males). Fear of dentistry was reported as the major etiologic factor, in non-urgency consultation, in. most studies, however, in the present study no statistically significant differences were observed between fear age, sex, level of education, smoking, Therefore, it is suggested that fear is not considered as a major factor in the present study. From among the total participants: 50.5% were without fear, 14.5% had a slight fear, 15.5% had a mild fear and 19/5% showed a severe fear. As a cconc1usion, in order to prevent more severe defects followed by more aggressive treatments, providing the patients with the knowledge about systemic consultation with a dentist seems a necessity.

A thorough knowledge of root canal anatomy and an understanding of its potential anatomic variations are essential for a successful root canal therapy. The most probable reason for failure is the inability to recognize the numerous variations in canal morphology. Mandibular premolars due to such anatomic variations, are considered the most difficult teeth for root canal therapy. If the entire root canal system is not properly located and treated, failure and flare- ups would follow.The purpose of this study was to evaluate the incidence of multiple roots and canals radiographically in mandibular premolars among an Iranian population referred to dental faculty of Shiraz university. One thousand and one hunrdeel (1100) full mouth series (FMS) radiographs of patients undergoing periodontal treatment were randomly selected. From among these radiographs, those full mouth series with four mandibular premolars free of any kind of root canal therapy, were included in the present study. Consequently, 1052 FMS were evaluated. From 2104 mandibular first premolars, 15% had more than one canal and 1.5% had more than one root. Among mandibular second premolars, 77 teeth (3.65 %) had more than one canal where as 9 teeth had more than one root. There were 107 cases with more than one canal bilaterally, from among them in 8 cases all four mandibular premolars had more than one canal, in 12 cases three mandibular premolars had multiple canals bilaterally and in (87) remaining cases only two. mandibular premolars had  bilaterally multiple canals. In nine cases of mandibular premolars. Multiple canals were observed bilaterally.The results of this study suggest that the probable incidence of multiple canals among mandibular first premolars is greater than mandibular second premolars. The frequency a multiple roots and canals in mandibular premolars are not affected by sex type. Since conventional radiographs in the department of periodontics are taken at a vertical angle to the teeth buccal surface, the probability of hiding multiple canals is high. Therefore, the mentioned results should be considered as the minimum probable cases for multiple roots among the teeth under investigation.

AIDS is a contagious disease that due to the absence of a definitive treatment and high prevalence, sterilization of contaminated instruments must be taken in to consideration.Dentist, upon the examination of the oral manifestations of AIDS, can play a critical role in diagnosis and prevention of further risks. The aim of the present study was to evaluate the knowledge, attitude and performance of dentists of Golestan Province, correspondent with treatment services insurance about the infection control and prophylaxis of AIDS. To do this study, 104 general dentists were thoroughly studied by a check list consisted of 32 questions arranged in three parts on knowledge, attitude and performance. The first part was completed by the dentists and others were completed by a student upon the observation of their offices. The knowledge level of the majory of dentists was good (52%), Their attitude was excellent (64.4%) and the performance of 66.3% was good. Most of the dentists employed disposable instruments. (Suction and glass 100%, apron 70.2% and needle 99%).They observed individual shielding covers (Single-use gloves 92.3%, protective glasses 82.7% and clinic dress 96.2%) Autoclave as the only sterlizator instrument was observed in half of the clinics (50%), however, autoclave and oven were in 42.3% of the clinics. The most commonly used antiseptic was microten (92.3%).It was concluded that the knowledge and attitude of dentists were at a high level although their performance was weak.Thus, they should be provided with facilities on dental equipment and periodic education.

Magnification in panoramic radiographies causes errors in treatment plans. The goal of the present study, conducted in the faculty of Dentistry Islamic Azad University (1382), was to determine the amount of such magnification in panoramic radiographies.To do this descriptive study, sixty samples referred to the radiology department. Were selected sequentially. A standard metallic ball with the diameter of 5mm was placed in the mouth, where as the actual size of the extracted tooth was measured by AACO caliper, at the level of 0.01 mm accuracy. Then, the balls and teeth images, prepared by panoramic radiography machine: TROPHY model odontorama PC were measured and examined by paired Hest. Following the measurement of the sample size and their images carefully and doing statistical tests, these conclusions were drawn:1- The amount of magnification, in the anterior region, in length was found 42% (P<0.0001) and that of width was 24.8% (P<0.0001).2- In the posterior region, the amount of magnification were 37.48% (P<0.0001) in tooth samples, 39.4% (P<0.0001) in ball samples, and in width 30.55% (P<0.0001) in tooth samples, 29.8% (P<0.0001) in ball samples. It should be mentioned that sex and age do not play any role on the results. Moreover, due to the low magnification difference between ball and tooth samples, the use of ball, to determine the amount of magnification in different region is clinically possible. The above mentioned machine has the following. 1- length of the anterior region2- length of the posterior region 3- width of the posterior region4- width of the anterior regionThus, it is recommended that all images should be prepared by an experienced operator, with a machine of the minimum magnification that the amount of it is explained beside the radiographs.

The palatal root of first maxillary molars has a buccolingual curvature.That in most cases could not be seen in radiographic images resulting in complications such as root perforation and ledge during canal preparation.Due to the importance of this subject, the present study was performed to evaluate the prevalence of buccolingual curvature and measuring the curvature angle of the palatal root of first maxillary molars among Yazd population.In order to do this study, 120 extracted maxillary molars were selected, mesiobuccal radiographies were taken, than using tracing paper the curvature of the palatal roots were determined by Schneider technique.The results showed that seventy- three cases (60.83%) were curved buccally, two cases (1.67%) were curved lingually and forty - five cases (37.5%) were straight. The angle of canal curvature was ranged from 0 to 30 degrees in 90 cases (75%), 30 to 45 degrees in 27 cases (22.5%) and 45 to 60 degrees in 3 cases (2.4%).

Nowadays brain strokes are the third common cause of death following heart attacks and cancers. Due to the fact that in most cases the occurrence of stroke is associated with severe and long lasting complications, its prevention has been the focus of various investigations the diagnosis of carotid artery calcifications via panoramic radiography are reported to be advantageous. Thus, the present study was designed to evaluate the prevalence of calcified carotid artery among over 45-year - old dental  population referred to oral and maxillofacial radiology department of dental faculty Shahid Beheshti University in 138I. In this descriptive study, the data for each patient were recorded in a questionnaire using medical history and interview along with patient's examinations finally, a total of 700 standard panoramic radio graphics, taken in the oral and maxillofacial radiology department, were prepared and interpreted by and oral and maxillofacial radiologist. The results of this study showed 52 soft tissue calcified lesions on radiographs, from among them 10 cases were of calcified carotid artery, 7 males and 3 females with the mean age of 64.8 years, ranging from 53 to 81 years. The left carotid artery was involved in 5 cases and the right carotid artery was involved in 3 cases where as in 2 cases both corotid arteries were calcified.Four individuals had no vascular risk factor (Excluding age and sex), while others showed at least one risk factor. Based on this study, the prevalence of carotid arteries calcification was found to be 1.4% in the population under study, 0.2% in the population age ranging from 45-55 years old and 3.1% among the individuals older than 55 years, which are in accordance with other reported studies in this field.