Journal of Dental School
Year:2005 | Volume:23 | Issue:2|Papers Count:21

Purpose: Oral lichen planus (OLP) is a common chronic immunologic inflammatory disease of skin and mucous membrane which associates with pain or discomfort. The status of OLP as a premalignant condition has been debated for many years. In some cases that are not pathogonomic clinical variations like plaque, specially erosive or bullous form, histologic examination is necessary for definite diagnosis or rule out possible dysplasia and carcinoma. 1- Sometimes pathologic results mention to OLP without any type of lesion (erosive, atrophic) 2- In some cases diagnosis is not clear and results are "compatible with OLP". In these cases DIF is necessary after routine histologic examination. The aim of this study is evaluation of direct immunofluorescence in diagnosis of oral lichen planus. Methods & Materials: In a retrospective case series study first, an 18 paraffin embedded biopsies were analyzed. All were confirmed histopatholigcally for OLP. These biopsies were collected since 1379, till 1381. All biopsies were examined by direct Immunofluoresence for the Presence of IgA, IgM and IgG antibodies in oral tissues. Data were analysed statistically by Fisher Exact test and percentage frequency.Results: 3 of 18 patients (16.6%) were male and 15 (83.3%) were females and their average age was 50.6 years. The common site of biopsy was in buccal mucosa (44.4%). Fluorescent globules were present in 11 patients (61.1%) that graded with base of fluoresent intensity to 3+, 2+, 1+. In 3 cases with white (keratotic) lesions 2 (66.6%) patients were DIF+ and in 11 cases with white and red lesions (keratotic, atrophic, erosive and bulluse) 8 cases (72.7%) were DIF+.Conclusion: DIF was positive in 61.1% of OLP patients. According to Fisher's test there was no significant differences between white (keratotic) and red (erosive...) lesions and DIF+ (P=0.67).

Purpose: This study was carried out for comparison of MTA and Root MTA (RMTA) by scanning electron microscope and energy dispersive spectrometer X-ray analysis.Method & Materials: In this research two resin discs were used and in each disc three cavities with three mm depth were prepared. In each disc the cavities were filled with one type of MTA and incubated in 37C for 48 hours. Then, they were polished, carbon coated, observed and analyzed by the scanning electron microscope and the X-ray energy dispersive spectrometer.Results: In both types of the cements results showed that calcium oxide (lime-CaO), silica (SiO2) and bismuth oxide (Bi2O3) were the most component respectively. The amount of minor elements (Al2O3, MgO and FeO) was very lower in RMTA in comparison with MTA. There were some similarity and differences in the amount of trace elements in both types of cements.Conclusion: There is a slit difference between the amounts of major elements in both types of MTA cements, but the amount of minor elements has a significant difference.

Purpose: Estimating the width of maxillary incisors may be difficult when artificial teeth are selected for edentulous patients. This study examined the relationship between mesiodistal width of four maxillary incisors (WFMI) and inner canthal distance (ICD).Methods & Materials: In this descriptive study, 100 subjects (50 male and 50 female; mean age 22.87 years) without facial and dental deformities were selected in this cross sectional study. WFMI and ICD were measured with Boley gauge. A mathematic formula to evaluate correlation between WFMI and ICD in 15 subjects has been used. (y = 1/784x-0/023x2) (y: mesiodistal width of four maxillary incisors, x: inner canthal distance). Then the difference between calculated size and real size of teeth was compared with paired t test.Result: The mean of WFMI was 32.95±1.47mm and the mean of ICD was 31.9±1.83 mm. In 70% of subjects, the difference between WFMI and ICD was less than 2mm. The correlation was r=0.345 (P=0). The calculated "model" for this relationship was y=1.784x - 0.023x2 (y: mesiodistal width of four maxillary incisors, x: inner canthal distance).Conclusion: 1- ICD is a good landmark for estimating WFMI. 2- The calculated model is competent and useful.

Purpose: Bifid uvula is the mildest form of cleft palate. The size of the cleft may vary from minimal to complete separation of the uvula into two lobes. The prevalence is %0.3-2.2 and is greater in males than in females (M/F:2.5/1). The disturbance appears to be autosomal dominant. This developmental defect may occur in syndromes such as Marfan, Crouzon, Apert and Pierre Robin.Case Report: In this report, the patient was 29 years old man whoever referred for dental restoration and scaling. He had Bifid uvula, dome - shaped palate, malocclusion and limited movement of mandibule. He didn't have any systemic problems and syndrome.

Purpose: Determination of need to orthodontic treatment is one of the main problems in our daily practice. Therefore, the aim of this study is to evaluate the orthodontic treatment needs of 12 - 13 year old students in Gorgan in years 2002-2003, using IOTN (index of orthodontic treatment need).Methods & Materials: A descriptive study using the technique of observation and interview has been performed by means of chart, ruler, tongue blade and color photographs of aesthetic component of IOTN. The method of sampling was cluster sampling and 793 individuals of urban and rural school children in Gorgan were examined.Results: According to dental health component (DHC) of ITON, 16.2 percent of school children showed great need and 16.9 percent moderate need to treatment and the frequency of slight or no need was 66.6 percent. The aesthetic component (AC) of IOTN in school children resulted in 7.1 percent great need, 20.9 percent moderate need and 71.9 percent no need.Conclusion: This study showed that the differences between IOTN values for boys and girls were not statistically significant the orthodontic treatment need in rural school children as significantly greater than urban school children, but most of them had no need or had slight need of orthodontic treatment.

Purpose: The purpose of this study was to evaluate and compare the histopathological inflammation of the periapex following preparation of the root canal with conventional and profile rotary instrumentation in cat's teeth.Methods & Materials: In this experimental study, thirty mature healthy cat were used. One canine was used as a negative control for every cat and three residual teeth were prepared with one of the following techniques of instrumentation: (1) step - back by using S-S K-type files, (2) crown down by using Ni-Ti files (3) by profile GT rotary system at 150 rpm speed. Vital animals were perfused at intervals 8, 24 & 48 hours after instrumentation. The canine teeth were separated from the jaws with some of the supporting structures. Then, decalcification and the laboratory processing were done. After obtaining data, they were analyzed with Kruskal Wallis test.Results: 1) The infiltration of inflammatory cells and infiltration of inflammatory cells into the bone marrow  was increased by passing the time and maximum infiltration was in 48 hour interval (P<0.05). 2) Although the amount of infiltration of inflammatory cells, edema, vasodilatation and infiltration of inflammatory cells to the bone marrow spaces in the groups of profile and crown - done were less than step - back but they didn't show significant statistically difference.Conclusions: Periapical inflammation in vital teeth without periapical pathosis was not statistically different following various methods of instrumentation.

Purpose: Streptococcus mutans serotype C is thought to be the principal causative bacterium of dental caries in humans. The overal purpose of the present study was to produce and purify the immunoglobulin Y anti - S. mutans from egg yolk.Methods & Materials: In this experimental laboratory study the S. mutans MT8148 (serotype c) was used as antigen. Hens were immunized with formalin treated whole cells by intramuscular injection. The eggs were collected daily, immunoglobulin Y was purified by water dilution method and ammunium sulfate precipitation followed by T - gel column chromatography. This product was characterized by electrophoresis. The activity of antibody was assessed by ELISA.Results: The immunoglobulin was observed in the  g- globulin region in electrophoresis. The optimum dilution of IgY was 1:20000 evaluated by ELISA.Conclusion: Titer of 1:20000 indicates high affinity or concentration of antibody against streptococcus mutans (serotype c). This product will be useful to assay and control the clonization of S. mutans in the oral cavity of human being.

Purpose: The purpose of this study was to compare the clinical and radiographic effects of Formocresol (FC) to that of Ferric sulfate (FS) in pulpotomized primary molars with carious pulp exposure.Methods & Materials: This study was performed as sequential matched controlled double blind randomized clinical trial. Sixty teeth of 30 children age 3- 6 years old were treated by a conventional pulpotomy technique. The identical teeth on two sides were randomly assigned to FC or FS. In the control group FC and in the experimental group FS was placed. The clinical and radiographic follow up was done at 3 months, 6 months and 12 months. The data was analyzed by chi - square test.Results: There was no statistically significant difference in successful clinical and radiological outcome between two groups.Conclusion: Ferric sulfate can be used versus formocresol in primary teeth pulpotomy.

Purpose: Contamination of dental unit water lines had been discussed to be the source of bacterial infection specially in immuncompromized and sensile patients in recent years. This study carried out in order to evaluate gram positive cocci contamination in the water lines of Shahid Beheshti Dental School units and drinking water supply of local area during 1381.Methods & Materials: The study was descriptive and its technique was observation and data questionnaire usage. 15 units from dental school and 15 ones from local area were selected randomly before the beginning of daily work. The samples were carried into transport media and sent to microbiology lab then. Smears of the samples were stained with gram staining and all specimens were cultured on blood and nutrient agar. The cases were incubated for 48 hours at 370C and microbial colonies were counted for the purpose.Results: No case of gram positive cocci contamination was observed in drinking water samples. In the examination of dental units' water, contamination of gram positive cocci and gram negative bacillus were seen, i.e. Entrococcus in periodontic Dept., Staphylococcus epidermidis in Orthodontic Dept. Staphylococcus aureus in Crown and Bridge Dept.Conclusion: The peak of contamination level was found in the third floor. Existence of gram negative bacillus in third floor and Enterococcus in first floor was probably for the contamination of water be fece, while staphylococcus epidermidis existence can be discussed by back flow of saliva via suction or water supply line of the unit through handpiece hoses.

Purpose: The role of cranial base flexure in determining the position of the glenoid fossa and expressing the anteroposterior position of the mandible has been under investigation for years. It is said that large Saddle angle can result in class II malocclusion; conversely small Saddle angle can cause anterior location of the fossa and resulting in class III malocclusion. According to this theory some investigators believe that class II malocclusion caused by large Saddle angle is difficult to influence with functional appliance therapy. The present study was aimed at evaluating the role of Saddle angle on dentoskeletal changes following the use of Two Piece Function Corrector (TPFC) functional appliance.Methods & Materials: Two groups of untreated skeletal Class II, Div 1 malocclusion were selected on the basis of Saddle angle degree. The first group (n=25) consisted of 13 boys and 12 girls with Saddle angle less than l22º  and the second group (n=25) included 8 boys and 17 girls with Saddle angle larger than 126º SNA, SN-B, , ANB, SN-Pog, Total Mandibular Length, Wit's, GoMe-SN, Body Mandibular Body Length, Ramus Height, N┴FH to A-N┴FH to Pog, IMPA, Overjet were measured before and after treatment by lateral cephalograms to evaluate dentoskeletal changes. Paired t-test was used to compare the differences between two groups and effect of TPFC on dento skeletal structures.Results: The two groups showed noticeable improvement in dento skeletal relationship. This study indicated no statistically significant differences between two groups.Conclusion: The amount of Saddle angle has no effects on treatment results with functional appliance therapy.

Purpose: Infective Endocarditis (IE) is a microbial infection of the endocardial surfaces usually involving the cardiac valves. Most cases of IE are caused by streptococci which from a large part of the normal oral flora. Staphylococci are the next most cause. These organisms are well equipped with surface determinants such as Fibronectin-Binding Protein and Fibrinogen-Binding Protein which mediate their adherence to the cardiac vegetations. In this study, the presence of these two cell-surface proteins has been detected by the polymerase chain reaction technique (PCR).Method & Materials: This research is descriptive type and all the samples were selected from the adult patients referred to shahid Beheshti Dental School. Fifteen people were selected with no systemic disease or any antibiotic consumption during the last two weeks of sampling. Regarding the teeth studied, none of them had sinus tract, pulp exposure, periodontal disease or deeply broken restorations with wide open margins.Results: Results show that, of 15 root canal samples, 11(73.3%) were positive for FnBP and 8(53.3%) were positive for FgBP. Regarding the endodontic treatment adjuncts like local anaesthetic administration, rubber dam placement or saliva control, we have also taken samples from gingival sulcus, caries and saliva in 11 patients of those 15 people. The relative frequency of FnBP in gingival sulcus, caries and saliva was 72.7%, 45.5% and 54.5% respectively and for the presence of FgBP in the same samples was 63.6%, 54.5% and 36.4% respectively.Conclusion: IE prevention in susceptible patients is a duty, but it is better for dentists to use preventive cares in all impacted patients.

Purpose: The purpose of this research was to determine the prevalence of mandibular first premolar teeth with 2 canals in the population of Kerman.Methods & Materials: A total of 280 extracted first premolar teeth were collected from several health service centers within the province of Kerman. Extracted teeth were stored in 10% formalin containers. Each tooth was initially cleaned with water and brush. Then the remaining periodontal tissues were removed by ultrasonic scalers.  Access cavities were made by diamond burs on each tooth and for complete removal of the pulp tissues the teeth were immersed within 2.5-3% Naocl for 24 hours. After washing and drying the teeth India ink was injected within the root canal system of the teeth by 27 guage needle. Then the specimens were dried and were decalcified within 5-10% nitric acid solution. The specimens were washed and were dehydrated by 70-95 and %100 Etanol solution. After clearing the teeth by %5 Methyl salicilate solutions the number and type of the canals of the teeth were determined and verified.Results: From the total of 280 evaluated teeth 14 teeth (%5) had calcified canals and %84.6 of the remaining 266 teeth had one canal and %15.4 of them had 2 canals.Conclusion: In our investigation the mandibular first premolar teeth with one apical foramen in apex is approximately 10% more than international findings.

Purpose: The purpose of this study was to evaluate the effect of occlusal reduction and some other factors and conditions on post-operative pain levels during endodontic treatment.Methods & Materials: In this experimental study, one hundred & twenty one patients requiring endodontic treatment in posterior teeth were selected. Specific clinical findings including gender, age, pulp vitality, sensitivity to percussion, preoperative pain, presence of periradicular radiolucency, swelling, and bruxism were recorded. Teeth with restoration to be maintained, greater than class I mobility, pocket depth >5mm, endodontic retreatment, endodontic failures such as root perforation and over instrumentation, and patients who had less than 3 occluding teeth in each arch and the ones taking pain altering medications were excluded from the study. Then canal instrumentation was done. Teeth were randomly assigned to 1 of 3 groups: (i) total occlusal reduction, (ii) simulated occlusal reduction, (iii) Control (occlusion untouched). A questionnaire was used to assess pain responses over a 24h postoperative period. The results were analysed using a χ2 test (p<0.05).Results: A significant differences were seen among 3 occlusal treatment groups and the patients' pain responses (P<0.05). Significant lower persentage of patients reported moderate and severe pain (17%) in total occlusal reduction group in comparison with simulated occlusal reduction (41%) and occlusion untouched (45%) groups. Also a significant relationship was found between the following preoperative conditions and post-instrumentation pain: Gender, tooth type, pulp vitality, preoperative pain, periradicular radiolucency.Conclusion: Females requiring endodontic treatment in molar with necrotic pulps, presence of preoperative pain and the absence of periradicular radiolucency experience more pain after instrumentation than other patients. Occlusal reduction is recommended in patients having all or some of the mentioned preoperative conditions to decrease patients' pain and discomfort.  

Purpose: Gingivitis is the most common form of periodontal diseases. Toothbrushing is one of the most important ways to control this disease. The aim of this study was to compare the effects of two Iranian toothpastes with an FDA - approved toothpaste (Crest Regular) to reduce gingivitis and plaque.Methods & Materials: Study was designed as a randomized controlled double-blind clinical trial. Three toothpastes(Pooneh and Nassim (Goltash Co.) and Crest Regular were prepared as the uniform tubes and divided between 3 groups. Each group contained 20 dental students with mild gingivitis which used an Oral B 35 toothbrush. Gingival index (GI); plaque index (PI); bleeding index (BI) and pocket depth (PD); were evaluated before study, and 3, and 30 days after study. Data were analyzed with SPSS software.Results: Bleeding index and plaque index was decreased in all groups during the study period (P < 0.001). There was no statistically significant difference among groups at any time. Also, gingival index showed significant decrease in any time in all groups compared to the first evaluation, but at the day 30, GI was higher in Nassim group than Pooneh group (P<0.005). Pocket depth showed significant decrease during the study period in all groups (P<0.001).Conclusion: All toothpastes had a good effect on plaque control and gingivitis.

Purpose: With consideration of importance of dental plaque and its effects on periodontal diseases and also the lack of knowledge about the effects of tooth brushing with and without toothpaste at noon times on the control of the dental plaque content in the fasting people, this research was carried out to investigate the effect of tooth brushing at noon with or without toothpaste on the control of dental plaque in fasting people.Methods &Materials: The type of study was sequential controlled experimental clinical trial and its technique was consisted of examining, interviewing and completing information forms. The research was carried out on 60 individuals (27 men and 33 women of 18-60 years of age and mean age of 39±1 who attended Periodontics Dept. of Shahid Beheshti Dental School regularly. The research was performed in two stages on two groups: (a) the group of the year 1381 who brushed with toothpaste and (b) the group of the year 1382 who brushed without toothpaste. Both groups were divided into two subgroups of control and case. The control group did not brushed at noon times and the case group brushed with and without toothpaste at noon times. In this study the plaque index of the individuals were taken in three stages. The first stage was taken one week before the beginning of the holy month of Ramazan that the tooth polishing of individuals of all groups were performed in this time margin. The second stage of taking index was carried out after the first 10 days of the Ramazan month. The third stage was carried out after the second 10 days of Ramazan. The plaque index changes were statistically determined by using paired t test.Results: The test result for the case groups showed a significant difference in decrease of dental plaquet. Test group (a. 1), (P<0.0001)and test group (a.2), (P<0.0001). t test:(p<0.001) Paired t test: Test group (b.1), (P<0.05) and test group (b.2), (P<0.04). t test: (p<0,001). The test result for control groups except one sample showed a significant difference of increase in dental plaque. Control group (a.1), (P<0.0001) and control group (a.2), (P<0.0001). t test:P>0.6. The control group (b.1), (p<0.04) and control group (b.2), (P<0.002). t test: P>0.6. T test: Test group (a) , test group (b) : (P<0.0001).Conclusion: Brushing teeth at noon time without Tooth Paste reduces the amount of dental plaque, although this reduction was not remarkable. Brushing teeth at the noon time with tooth Paste reduces amount of Dental Plaque remarkably. Lack of brushing teeth at noon time in fasting people enhances the amount of dental plaque on teeth.

Purpose: Cleft of lip and palate is the mostly reported congenital deformity in maxillofacial region. In spite of this, there is no comprehensive published study in the country. So, this study was conducted in order to evaluate the prevalence of cleft lip or cleft palate in infants born in Tehran Mahdieh Centre during the years between 1370 and 1379.Method & Materials: The study was carried out descriptively and analytically on existing data. The study included infants' files born with cleft lip or palate (or both) in Tehran Mahdieh Centre during 1370 till 1379. The prevalence of cleft lip and palate, the mothers' age, the mother gravity and blood group were studied.Results: A total number of 87838 files were studied, of which, 131 infants were born with the mentioned deformities. 63 cases were females and 68 cases were males. The prevalence of cleft lip, cleft palate and both were 31.8%, 25% and 43.2% respectively. Cleft lip and cleft palate together was observed mostly in males while cleft palate had the same incidence in females. 24.2% of infants had anomalies other than cleft lip and palate. Familiar relationship was noted in 28% of cases. The age of infant's mothers was 25.6±6.6 years. The most observed mother gravity was first gravity which was about 35.1%.Conclusion: The overall prevalence of cleft palate in the studied centre was 1.49 in 1000. The incidence rate was almost the same in both sexes. The incidence of lip and cleft palate together was more than lip and cleft palate separately. 77.1% of the infants had normal pregnancy period. Gravity of deformed infants' mothers was 2.9±2 and the blood group of O was the most observed blood group in mothers.

Purpose: The aim of this study is to evaluate the success of the application of OSDC implants to restore single missing teeth.Methods & Materials: This retrospective investigation involved placement of 54 Neo-Dent system OSDC dental implants in 36 patients. Exclusion criteria was as follows: psychological disorders, bruxism, smoking habit, anticipate lack of patient compliance. The teeth were needed to replace by dental implants as follows: Maxillae, (Incisors 18 implants, Canines 9 implants, Premolars 7 implants, Molars 5 implants). Mandible, (Canine 3 implants, Premolars 9 implants, Molars 3 implants). After the healing period, an envelope flap was made, the abutments installed and open flap impressions provided. Immediately acrylic temporary crowns adjusted and cemented. The dental implants followed after one year of loading.Results: Except two implants in one patient, all other implants were stable and passed our criteria of success at the time of abutment connection and one year after loading, and subsequently all implants were provided with prosthetic restorations. The rate of bone resorption which have been studied by radiography were as follows: the mean of 0.4 mm, minimum of 0.2 mm and maximum of 0.8 mm.Conclusions: Replacing single teeth with OSDC dental implants of Neo-Dent system can be applied successfully.

Purpose: Methods of tooth brushing are amply described, but procedures for maintaining their cleanliness are discussed infrequently. The purpose of this study was to evaluate the level of microbial contamination of toothbrushes.Methods & Materials: The study has been done in a descriptive, retrospective, analytical way. Information about the methods of toothbrush care were obtained by a questionnaire filled by 100 individuals. Toothbrushes were gathered and examined in two culture media; Blood agar for gram positive microorganisms and E.M.B for gram negative microorganisms. All surfaces of a toothbrush were separately pulled three times on two culture media. Then culture media were incubated in 37°C and were read in three stages: 24, 48, 72 hours by eye and microscope. Level of microbial contamination was divided into three groups on the basis of colony count. Low contamination: colonies < 10000, moderate contamination: 10000 - 30000, high contamination: > 30000. Statistical analysis in this study was as follows: 1- Chi - square for trends, 2- Fisher exact test, 3- Spearman correlation coefficient and 4 -Mann - Whitney test.Results: Overall 96% of toothbrushes were contaminated. Some variables such as type of toothbrushes, frequency of tooth brushing, time of toothbrush usage had no effect on CFU (Coloni forming unit). However, location of toothbrush for example toilet or bathroom, washing and drying method, use of cover after tooth brushing, oral hygiene had relationship with CFU. (P<0.05)Conclusions: Toothbrushes in regular use can become heavily contaminated with microorganisms. Storage conditions and skill in washing and toothbrush care are effective in reducing the level of their contamination.