Journal of Dental School
Year:2002 | Volume:19 | Issue:4|Papers Count:16

Radiolucent odontogenic lesions are considered as one of the main groups in the pathologic lesions of jaws. Proper diagnosis associated with correct treatment planning is therefore necessary. In this study, a total of 196 lucent odontogenic lesions were found between 1056 lesions which had been originally referred to the Oral and Maxillofacial pathology department at Beheshti Dental School. Cases were including 103 male and 93 female patients. Results showed that the most common lesion as being Radicular cyst with 49 cases (25%) and the least .common Lesion as both Lateral Periodontal cyst and Mandibular buccal infected cyst, with only 1 case (0.51%). The peak incidence was observed in second decade of patient's life. These lesions were seen at 40% of the cases in maxilla and 60% of the cases in mandible.

The aim of this study was to mvestigate the effects of daily tooth brushing frequency on the amount of supragingivaldental plaque and gingivalbleeding. This randomized matched controled single blind clinical trial.was conducted on 36 final year dental students at Shahid Beheshti Medical Sciences University (age 18-21 years).After preforming initial preparation inclouding Oral hygiene instruction and a supragingival scaling recalled after two weeks for their baseline assesment. Plaque and Bleeding Indices were measured and recorded the forms prrovided. Cases were then randomly divided in to two groups. The first group was asked to brush two times a day while the second group had to brush four times a day. An assessment was carried out in a 6 weeks, time to measure the indices. Results showed a significant diffrence between Plaque Ind ex of two groups with a considerable reduetion in four times brushing group.However, no significant difference was found between the Bleeding Index of the two groups.

Surface characteristics and morphology, specially surface roughness of dental amalgam, can influence the surface plaque accumulation, gingival inflammation, recurrence of tooth caries, tarnish and corrosion behavior of the alloy. This study was designed to evaluate the effect of the particle shape of amalgam alloy on the surface morphology and roughness of amalgams in addition to this effect from carving, burnishing and polishing.Four types of commercial amalgam alloys with different particle shapes were used for this investigation including lathe cut, spherical, spheroidal. Twenty one samples were prepared from each amalgam in special mold. Following aninitial trituration and condensation; samples of each amalgam alloy were divided into three groups and each group was finished and polished using one of three following procedures; carving, carving - burnishing, carving - burnishing polishing. SEM Technique was used to investigate the surface morphology of amalgams. The mean values were statistically compared using ANOV A and Duncan tests at 95% level of confidence.Results showed a statistically significant difference between three different groups of each amalgam in their surface roughness (p<0.05). The mean surface roughnesses of the" carved four amalgam types indicated a significant difference between groups (P<0.05). However, the carved - burnished groups and carved burnished - polished groups had no significant difference (P>0.05).It seems that the shape of the particle has a clear effect on the surface roughness, however, a good finishing and polishing could usually compensate this effect.

Mandibular second molar has been proved to have the widest variation in canal configuration. This could directly effect on the result of any endodontic treatment needed. cooke and cox reported a shaped secondmdar root canal with a slit continuing from the mesionlingual to mesiobuccal. canal even to the distal canal or canals.Second premolar has also been reported with some variations. This article will discuss 2 unusual cases of mandibular second molar with C from configuration and a mandibular second premolar with 3 roots with 3 canals.

As acknowledged, patient's with learning difficulties have problems using conventional brushes with different techniques. This investigation was designed to evaluate its efficacy and applicability for this group of patients in comparson to a conventional brush (oral-B). A group of 50 male institutionized pupils were selected who were between 6 to 14 years of age. Cases were randomaly selected and divided into two groups each of which had used one tooth brush for a month followed by the use of the second brush for the second month. A one week wash out was also considered between the two periods to eliminate the period effect. Results indicated that there was no significant difference between the level of plaque removal in two groups.In conclusion: The use of super brush has been proved to be as effective as the conventional brush while removing the need for al1¥ detailed training in this particular group of children.

Damage of the Lingual nerve is one of the most common problems during any procedure in oral surgery, especially during removal of the third molar. Following a microsurgical removal and damage recieved by the Lingual nerve, there is a lack of regeneration of the gustatory fibers in comparison 10 the sensory fibers. The histologic investigation of 200 Cadaver Lingual nerve preparations showed that the Chorda-tympani fibers distribute widely in the fascicles of the Lingual nerve. It is therefore concluded that the chance of the gustatory.fibers, regeneration in the third molar region, is very low, following microsurgical reconstruction of the Lingual nerve.

Hygroscopic expansion is an important property of restorative materials which play a significant role in the clinical performance of the materials. The aim of this study was to evaluate the hygroscopic expansion of a conventional glass-ionomer cement (Fuji II) , a resin-modified glass-ionomer cement (Fuji II LC), a composite resin (Z100) and a compomer (Compoglass). Ten samples (6x4 mm) were made using a two-part stainless steel mould. Samples were immersed in distilled water or natural saliva during the period of the study. The length of each sample was measured after preparation at: 24 hours, 1 week, 2 weeks, 1 month, 2 months and 3 months. The linear hygroscopic expansion was presented in the form of percentage for the length changes of the specimens in relation to the baseline measurement. Results indicated that Fuji II has no significant expansion in both storage medias during the study, whereas Fuji II LC exhibited the highest expansion rate among the materials tested. It was also found that the pattern of the expansion of Compoglass was similar to that of the composite resin tested. It was concluded that the linear hygroscopic expansion of the resin-modified glass-ionomer was more than the other materials and natural saliva had no effect on the magnitude of the expansion.

Oral cancer accounts for less than 3% of all malignant tumors in Western communities. It is considered as a world wide health problem. High mortality rate of such cancer may be attributed to the lack of effective oral examination by dentists. This study was designed to assess the dentists knowledge and his/her diagnostic skills on oral cancer. A questionnnaire was prepared to obtain related information on the level of knowledge and diagnostic skills of a group of Kermanian dentists for oral cancer. Questionnaires were distributed between 65 general dental practitioners in the city of Kerman. Results showed that the mean knowledge score (5.8 out of 11) and diagnostic skill score (1.6 out of 3) of the participants were low. There was a significant correlation between the diagnostic skill and knowledge scores (P<0.05). There was no significant correlation between most of the individual characteristics, evaluated in this study.

This study was designed to evaluate quantitatively the orthodontic tooth movement (OTM) following injection of PGE2 with and without calcium gluconate and its comparison to OTM without consumption of any drug. 24 male wistar rats (8 weeks old, body weight = 230-300 gr.) were divided randomly into 3 groups. A similar appliance (closed coil spring) was used for all groups. The closed coil spring was tied to upper right first molar which was then pulled (force equal to 60 gr.) and tied to the right incisor. The first group did not receive any drug. The second group received submucosal injection of PGE2 (0.1 ml of 1mg/ml) on days zero and seven. The third group received an IM injection of calcium gluconate (200 mg/kg) in addition to the PGE2. All of the animals were sacrificed and the distance between the upper right first and second molars were measured by special gauge on the twenty-first day. Results indicated that the average rank was as follows: control group=7.94, PGE2 group = 16.25, and PGE2 + Calcium Gluconate= 15.63. There was a statistically significant difference amongst the medians at the 95.0% confidence level (P<0.05). To determine which medians are significantly different from others, Box-and- Whisker Plot was selected to be carried out with selecting the median notch option. It is concluded that: prostaglandin E 2 can increase tooth movement as a primary messenger. Calcium injection redues root and bone as well as reducing resorption the level of tooth movement.

Today, new methods are applied for oral health promotion. Implemel1tation of such methods are only possible if the level of knowledge in the community is at a certain level. This investigation was designed to look at the level of this knowlege in a group of Iranian school children. A group of 768 students were randomly selected form 19 districts of the city of Tehran. This descriptive study was performed by collecting information through a questionnare. Results indicated that 9.2% of boys and 13% of girls had received some degrees of oral. health knowledge through their teachers. Regular dental check-up was noted only in 13% of girls and 3.3% of boys. Only 15% of the population- were aware of the consequences of early loss of primary teeth. -30.2% of boys and 48% of girls were agreed upon toothbrushing as the most improtant principle of oral health maintenace. Pupils believed that fluoride supplement is essential for healthy teeth. Finally, 90% of the cases believed in the cariogenic effect of choclate. Inconclusion: Pupils of this study had a relatively good level of knowledge on oral health. Their knowledge was mainly obtained from media, dental visits and the efforts of health workers within the community.

This investigation was carried out to. find the frequency of published articles related to periodontics in current persian text journals. Attempts were made to collect the data including abstracts of periodontal articles with their detailed information such as: the title, source, author's name, year and place of publication. The type of the articles was also defined for a further classification. Results indicated that the total number of the periodontics articles being 248, with 159 of them being the research based and 89 of them were review articles. Surprisingly 83 articles were also been translated from other English text journal.

Desmpoplastic ameloblastom (D.A) is an unusual sub-type of ameloblastoma. The location of this lesion, differ from the coventional ameloblastoma as well as its histological and radiological features.Differential diagnosis of this case include benign fibro-osseous lesion, squamous odontogenic tumor, and calcifying odontogentic tumor.Usual treatment of D.A is similar to conventional ameloblastoma in the form of enbloc resection, hemirnaxillectomy, or hemi mandiblectomy. Occasionally conservative procedures such as enocleation could also be undertaken. The follow up period of the procedure has been usually reported in short termsoreven is unknown.This article reports an interesting case of D.A in maxilla with a 2 years follow up sub sequent to a conservative treatment.Results of this work showed that clinical behaviour of the less ion differs from conventional ameloblastoma.

For more than three decades, pit and fissure sealants have been studied during many didactic and clinical trials. The assumption that tooth prophylaxis with those materials could prevent pit and tissue caries, had accounted for widespread use of pit and fissure sealants. Recent years have witnessed progress of Glass lonomers as sealants and also fluoride-containing Composite Resin sealants. This article had reviewed the vital advent of sealant technology including the use of Bonding Agents, Primers and Reinforced Composites.