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A. Kousari , J. Mahmoodian , A. Rashidian ,
Volume 13, Issue 3 (10-2000)
Abstract

The purpose of this study was to assess the fluoride release of three fluoride- containing materials exposed to fluoride solutions. This study compared the initial fluoride release and release following re-fluoridation (neutral or acidic 2% NaF) of three different filling materials, conventional glass ionomer cement (CG1C), resin- modified glass ionomer cement (RMGIC), polyacid- modified composite resin (PAMCR). Twenty discs of each material, measuring 2mm height and 6mm diameter, were suspended in separate vials of 2" laboratory artificial saliva. The amount of fluoride release was measured over two periods of 28 days each. Fluoride release was determined at 1,3,7,14 and 28 days of each period. Fluoride was measured with a fluoride ion- specific electrode and an ion analyzer previously calibrated with standard solution .T- test and ANOVA were used to evaluate the data. Fluoride release for all products at days 1 and 3 was significantly greater than the rest of the time intervals. Then, the fluoride release decreased significantly. CGIC released significantly more fluoride than the other products. This was followed by RMGIC, which exhibited significantly more fluoride release than PAMCR. In second period of experiment, the specimens were assigned to two subgroups often each. The samples exposed to two different solution of NaF (neutral or acidic). All groups showed the capacity of re-fluoridation and fluoride uptake. The specimens exposed to acidic NaF solution showed statistically more significant rechargeability than the neutral NaF solution. It may be concluded that glass ionomer cements act as a rechargeable slow fluoride release systems and as an effective caries preventive material in caries preventing programs for caries susceptible children.


Mh. Shahroodi , H Berenji ,
Volume 14, Issue 1 (7-2001)
Abstract

Many different methods are suggested to restore endodontically treated teeth. Prefabricated posts can not be indicated for all teeth and cast posts require extra time and cost. In addition, with the introduction of full ceramic restorations, achieving the ideal esthetic with metal post underneath them may be problematic or impossible because the darkness of the metallic posts may show through the highly translucent all ceramic restorations. In this article the review of litature and describiton of applied methods of different procedure in restoring the root canal therapied teeth and few techniques of non metallic posts fabrication such as fiber reinforced composite and zirconium oxide posts have been described.
F. Haghighati , N. Ayobian Markazi ,
Volume 14, Issue 1 (7-2001)
Abstract

One of the special kinds of periodontal disease is rapidly progressive periodontitis (RPP). This form of periodontitis is an aggressive disease, which results in bone destruction and loss of periodontal attachment 4 to 5 times more than adult periodontitis or slowly progressive periodontitis. The purpose of this study was to investigate the presence of Actinobacilius actinomyct-em comitans (Aa) in RPP patients. A total number of sixty samples was collected from 15 patients with RPP and cultured inanaerobic conditions. Results showed the presence of Aa in 13 patients (86.7%), while 29 samples were Aa positive (48.3%). Two of the RPP patients (13.3%) were Aa negative even after two times bacterial culturing.


Ar. Talaeipour , Gh. Mohammadian , D.  ghoudarzi ,
Volume 14, Issue 2 (8-2001)
Abstract

Osteodystrophy is one of the most common complications at the last stage of renal disease,which cause low bone mineral density (BMD) and skeletal deformities in patients. In this study evaluation of renal osteodystrophy was evaluated through BMD measurement of 45 under dialysis and 78 healthy persons by intra-oral digital radiography (RVG). Results Showed that:1- The average of BMD in hemodialysis patients was indeed lower than normal population (P^O.OOO).2- The mean of BMD of females was lower than males (P=0.021).3- There was no correlation between and BMD (P=0.560).4- Age and BMD had no significant relationship (P=0.648).5- There was negative correlation between alkaline and BMD therefore ALP is a useful predictive factor forBMD(P=0.002).
M. Ghavam ,
Volume 14, Issue 2 (8-2001)
Abstract

Oral cancers account for a relatively high percent of neoplasms in the elderly population. Treatment protocols often include anti-neoplastic pharmaco-therapeutics, irradiation of the head and neck region, and surgery. These treatments, specially radiation, have detrimental effects on oral hard and soft tissues. Salivary glands undergo a distinct and longterm dysfunction, which leads to decrease in salivary How. Xerostomia is a common clinical problem in these patients which contributes to dry mouth, mucosites, change in oral ecosystem and dental caries, followed by difficulties in speech, swallowing and use of dentures which cause malnutrition. This phenomenon has an irreversible weakening effect on the patient's health. To prevent this negative impact on oral health in this group of patients, definitive dental treatments prior to the initiation of medical therapies is imperative, and will decrease the morbidity rates. Today's dentistry benefits from improved methods and materials, which enable us to give these patients a better preventive dental treatment. Consultation between dentist and medical team would be the best way to help our sufferer patients.
Y. Refua , N. Abbas-Zadeh. ,
Volume 14, Issue 2 (8-2001)
Abstract

Different techniques for local anesthesia are used in the mandible. The purpose of this study was to determine the effects of inferior alveolar dental nerve blocks by comparing the two akinosi and conventional techniques. 80 patients (aged 15-60 years old) were randomly divided into tow groups for extracting the mandibuler posterior teeth by akinosi and conventional techniques. Patients were all injected with 1.8 ml of Lidocaine 2% plus Adernaline j^nnnn .Then the Pain Sensation during injection,positive aspiration, beginning time of anesthesia, duration of anesthesia depth of anesthesia, and the anesthesia of soft tissue related to sensory nerves were evaluated. The results showed that the pain sensation in conventional technique was significantly higher than that of akinosi technique. The number of positive aspirations in conventional technique (12,5%) was higher than that of akinosi (5%) but not significantly different. The long buccal nerve anesthesia in akinosi technique (75%) was significantly higher than that of conventional technique. There was no significant difference between the two techniques for the depth of anesthesia. The success rate was 87.5% in conventional technique and 80% in akinosi technique. The average time of lips anesthesia in conventional technique was 3 minutes compared with 4 minutes in akinosi technique, which was not significantly different from each other. However, the beginning time of aneshtesia in tongue was significantly lower in conventional technique. No significant difference in the duration of anesthesia in lips and tonques between the two techniques was observed.
N. Eshghyar , M. Bateby ,
Volume 14, Issue 2 (8-2001)
Abstract

Different methods can be used to treat the malignant disease surgery, radiotherapy, chemotherapy, and even cryotherapy are different approach to reach the best treatment for patients. The aim of this cross sectional study was to evaluate the prevalence of oral side effects followed by chemotherapy of cancerous patients in Imam Khomeini hospital. This study was conducted on 80 patients who were under chemotherapy more than once and their oral lesions were evaluated considering their physical conditions. Mucositis was the common problem (66.2%) and the most involvement area was observed in tongue (55%). High percentage of this lesion in adult and senile might be due to deficiency in their immune system.
Ms. Ahmad Akhondi ,
Volume 14, Issue 2 (8-2001)
Abstract

The purpose of this study was to evaluate Y shape appliance for expansion on maxillary arch of patients in their mixed dentition age. Eight patients, 6 girls and 2 boys, with maxillary constriction, retrusion of maxillary anteriors, and space deficiency of upper canine were treated by Y-plate expansion. For each patient 8 parameters on upper cast and 7 parameters on lower cast were measured. Statistical analysis was conducted by calculating the mean, standard deviation and p-value, of parameters. Since these parameters change during natural growth, the results were compared to normal growth changes of similar patients group form another study as control. Results showed significant increase in maxillary and mandibular cervical and coronal intercanine and intermolar width (P<0.005). The results also showed significant increase in maxillary arch length and perimeter.
H. Razmi , M. Salavati Zadeh ,
Volume 14, Issue 2 (8-2001)
Abstract

The idea of using chemical agents in removal of obstructions on the walls of root canals has been existing since years ago. Successful attempts in this area have been made with the introduction of RC-Prep materials in root canal preparations. The aim of this study was to compare the decalcifing potency of two chelating agents in root canal preparations. 30 extracted canines were divided in three groups for use of Re- Prep materials. Group A Rc-Prep (Primer) made in USA, group B Re- Prep (RC-CTF) made in Iran, and group C as control. Root canals were prepared using standard method followed by washing with 5% sodium hypochloride. Then the teeth were divided into two sections of mesial and distal by a special cutting device. The amount of calcium on polished sections was measured using an elemental analysis method (electron beam probe system). The mean value data were analysed using one‌way Analysis of Variance (ANOVA). The mean values for the measured calcium were group A: 28713±1129, group B: 39441+680, and group C: 54458±2024 . Statistical analysis showed that the mean value for group A was significantly different from other groups. There was also significant difference in the mean values for group B and C. The results indicate that the decalcifing potency for Rc-Prep (Primer, USA) is significantly higher (PO.001) than that of Rc-Prep (RC-CTF).
Sh. Jafari , N.  ebrahimi-E- Daryani , S. Zeinali, M.  motalleb Nejad ,
Volume 14, Issue 2 (8-2001)
Abstract

Helicobacter pylori infection causes gastric and duodenal ulcer. However recurrence of infection after eradication would suggest the existence of other reinfecting sources in the gastrointestinal tract (Gl). The aim of this study was to assess the existence ofhelicobacter pylori in dental plaques of patients harboring Helicobacter pylori in their GI tract. Antral biopsies were taken from 40 patients with Gl problems and cultured. Samples were also taken from dental plaques of patients with positive Helicobacter pylori culture under microaerophilic conditions and evaluated by polymerase chain reaction (PCR) reamplification. The mean age of patients was 40 years 24 (60%) male and 16 (40%) female. The results obtained from dental plaque cultures, which analysed by PCR were all negative, however 7 (17.5%) cases were found positive by PCR reamplification. The results showed that Helicobacter pylori could exist in dental plaque and PCR reamplification could be used for its detection as a more sensitive technique. More research should be conducted to examine any relation between the existence of Helicobacter pylori in dental plaques and recurrent GI disorders.
M. Bidar , P. Ghaziani, M. Saatchi , Ma. Soluti ,
Volume 14, Issue 3 (9-2001)
Abstract

Endodontic postoperative pain is still one of the major problems for dentists. According to the researches periapical inflammation after RCT is one of the most important factors causing endodontic postoperative pain. Histamine is one of the effective chemical mediators, which produces such inflammation. So, for controlling pains after RCT, the factors reducing inflammation should be found. The aim of this study was to investigate pain control after RCT by drug prophylaxis with antihistamine (asetemizole). 60 patients were divided in 2 groups (30 patients in each group). Group 1 had a capsule of  asetemizole (20mg) and the second group had a placebo capsule one hour before RCT. The patients completed the questionnaire after RCT and gave it back on the next session. The evaluated times were 1, 3, 6, 9, 12, 18, 24 and 72 h after RCT. This study indicated that asetemizole was able to reduce the moderate pericemental pain just at the 9 and 12 hours after RCT, and it was not able to reduce the spontaneous pain after RCT significantly on the evaluated times


M. Pak Nejad, Am. Rokn , H. Semyari ,
Volume 14, Issue 3 (9-2001)
Abstract

The aim of the present study was the histological evaluation of Enamel Matrix Derivative (EMD) effectiveness for regeneration of periodontal defects. EMD activates cementum synthesis, PDL and bone during the maturation stage of follicole. In this research, EMD was used in surgical defects of premolar teeth in four adult sheep. Muccoperiosteal flap was reflected in buccal site of teeth. The buccal bone plate was removed from mesial to distal in 4 mm depth. After eliminating the cementum by bur and its etching, EMD was applied on exposed dentine and flap was sutured. In opposite sites of those teeth (control sites) the same process was performed without etching. After 100 days, sheep were sacrificed and histological study through light microscopic was performed on black sections of operation sites. The results showed that in test sites, regeneration of cementum and bone was 62/5% and 42/5-50% respectively. But in control sites regeneration of cementum and bone was 37.5% and 32/5-42/5% respectively. Also the migration of junctional epithelium in control sites was 8-10% more than test sites. The important point is that in test sites, cementum was completely attached to undermining dentine. But, in control sites, the gap between cementum and dentine was visible. As a result, this study suggests that EMD promotes periodontal regeneration, and EMD application is a successful achievement in regenerative periodontal therapy.


M. Ghavam , T. Jafarzadeh, P. Alizadeh Oskouei ,
Volume 14, Issue 3 (9-2001)
Abstract

 Polymerization shrinkage of light cure composite resins causes many complications in conservative and esthetic restorations. The objective of this in-vitro study was to evaluate the polymerization shrinkage, degree of conversion and the amount of filler in IDM and tetric ceram composites. Ten disk shaped, uncured specimens (8mm×1.547mm) of each composite were placed on glass slide in the center of the metal attached to it. Then specimens were light cured for 60s from underneath. After 30 minutes, the thickness of specimens, using a micrometer and the percent of the polymerization shrinkage of each sample were measured. Statistical analysis was carried out by t-test (P<0.05). Also the degree of conversion of specimens was evaluated with FTIR and the mineral filler content was measured by burning in electric oven. Polymerization shrinkage in IDM and tetric ceram was not significantly different. Degree of conversion and mineral filler content in tetric ceram was greater than that of IDM.

It is assumed that the low degree of conversion in IDM is due to its chemical composition and filler content. Also, the similarity in linear polymerization shrinkage between IDM and tetric ceram may be caused by the low degree of conversion in IDM.


S. Eshraghi , Mh. Salari , Z. Kadkhoda , Sh. Yaghmaei ,
Volume 14, Issue 3 (9-2001)
Abstract

Actinomyces species are normal residents of the mouth cavity, gastrointestinal tract and female genital tract. The genus consists of gram-positive bacteria, strictly anaerobic or microaerophilic. The bacteria are opportunists with a low virulence potential that cause actinomycosis only when the normal mucosal barriers are disrupted. The main purpose of this study was the isolation of Actinomyces strains and determining of their role in periodontal diseases. The present study was carried out on 100 patients with periodontal diseases referred to the Periodontic Department of Faculty of Dentistry. The sampling was done in 6 months with isolation of oral Actinomyces from microbial plaque and periodontal pocket. The samples were selected based on the following criteria: periodontal plaque with deep pocket (>3 mm), no antibiotic therapy for a period of at least two weeks, and lack of systemic diseases. One strain of Actinomyces viscosus and two strains of Actinomyces naeslundii were isolated from the patients with gingivitis and periodontitis. Of the 100 patients with gingivitis and periodontitis, aged between 18-57 years old, 46% were males and 54% were females. The peak incidence of the diseases (35%) was in the third age group (31-40) and the lowest incidence (10%) was in the first age group (<20). Forty patients (40%) complained of gingival disease and its bleeding with lower incidence of (42.5%) in female.


Z. Pourpak , M. Shahrabi , J. Nikfarjam , M. Moazeni , L. Nikfarjam , A. Aghamohammadi ,
Volume 14, Issue 3 (9-2001)
Abstract

IgA selective deficiency is the most common immunodeficiency. The prevalence of it in different races varies from  to . Since secretary IgA has has a defensive role in the mucosal surfaces, supposing is thought that IgA deficiency will be accompanied by oral manifestations. The previous studies showed controversial results about that. The aim of this cohort study was to finding out oral manifestations in IgA- deficient individuals. As s result oral specialists can find the patients in early stages. 11 IgA- deficient patients (with IgA level < 10 mg/dl in serum) and 11 normal volunteers with the same age and sex were compared. The ages of the people were between 3 and 18 years old and 5 girls and 6 boys were in each group. Their oral examination included DMFT (Decayed, Missed and Filled Teeth), periodontal condition, Plaque accumulation and oral mucosal lesions. Saliva immunoglobulin and secretary component levels were detected by enzyme- linked immunosorbent assay (ELISA) and serum immunoglobulin levels were detected by single radial immunodiffusion (SRID) methods. All of the IgA- deficient patients had the serum IgA level < 10 mg/dl and their immunoglobulin levels were normal.  of these patients didn't have SIgA and the rest of them had a little SIgA in their saliva(<  SIgA levels in sex and age matched normal group). IgA deficient patients showed no statistical significant difference about oral manifestations in comparison with normal group. It may be related to the increase of compensatory SIgM or assistance of other non- immunological defense factors in saliva, phagocytosis and cellular immunity. Thus IgA- deficiency cannot produce any oral manifestations as a criteria to diagnose it.


H. Razmi , D. Sharifi , F. Sasani , M. Eghdami ,
Volume 14, Issue 3 (9-2001)
Abstract

The cleaning and shaping of root canals is one of the most important proccesses in endodontics. In many cases, the physiologic or pathologic proccedures can affect the canals. So, using the instruments and materials, which could be applied in cleaning and shaping of narrow canals is necessary. The aim of this study was the evaluation of Iranian and foreign chelating agents on periradicular tissue of cats. After cleaning and shaping of canals in 18 lower canines of cats, the original RC-Prep and an Iranian chelating agents were placed equally in two groups with 9 teeth in each one. The patency of canals preserved for materials leakage. In 3 lower canines of cats, phosphoric acid was placed as positive controls.3 canine teeth as negative controls had nothing in them. The crowns were sealed and the cats were sacrificed in 1/21/42 days periods after conducting vital perfussions. The teeth samples with their surrounding osseous tissues were gathered and placed in three groups each contained 6 samples. Histologic preparations were done and the tissue reactions to these materials were evaluated by counting the proliferative inflammatory cells. Also the morphometric analysis for these samples was done. The inflammatory reactions of these materials (the original RC-Prep. & the Iranian chelating agent) were not statistically different. Both of these materials were different in inducing tissue reactions in comparison with those of positive and negative controls, and these differences were statistically important.


B. Seraj ,
Volume 14, Issue 4 (1-2002)
Abstract

Whenever the first permanent molar is extracted or its long- term prognosis is poor, before taking any steps, a full clinical and radiographic evaluation associated with patient's dental models investigation is necessary to determine the following cases:The quality and quantity of dentition, teeth missing, occlusion, buds position, orthodontic problems, the level of parents and patient cooperation for future long term orthodontic treatment and finally patient's oral hygiene. On the basis of this information, a decision is taken about the first permanent molar extraction with poor prognosis, either of balancing or compensatory type, especially when future orthodontic treatment is improbable. The aim of this article is to explain the principles of time and sequence of first permanent molar extraction.
F. Aghahosseini , M. Enshaei ,
Volume 14, Issue 4 (1-2002)
Abstract

Epidemiologic studies have shown that caris or "infective damage of hard tissues in teeth" are the most common type of infection in human. In Iran, a few studies have investigated this hygienic problem, but no practical results have been defined yet. In this research, the conditions of the first upper and lower permanent molars (it contains four minor variables), have investigated. For this reason, in a descriptive analytic study, which was of retrospective and cross- sectional type, one thousand files were chosen systematically. The data were analysed by SPSS packages. The mean values of DMFT for permanent first molars were 3.47±0.50 (MT-1.23, FT=0.86, DT-1.38). The number of extracted teeth in mandible was moer than maxilla and the number of untreated caries teeth in maxilla was more than mandible (PO.001). DMFT ratio of the first molars to total DMFT, was approximately 29%, which indicates that caries and that complications on the first molars, make the main part of the overall DMFT. Therefore, hygiene training, preventive methods and the improvement of ecomonical status seem necessary in dental services.
E. Yasini , N Mohammadi ,
Volume 14, Issue 4 (1-2002)
Abstract

Posterior composite restorations, due to polymerization contraction, result in microleakage. Different methods have presented to reduce this phenomena. The aim of this study is to evaluate the effects of flowable and condensable composites to reduce microleakage. Seventy extracted human teeth were prepared with proximal class II cavities with gingival margin 1 mm below CEJ. The teeth randomly were divided into 7 groups. Groups I & II were restored with a dentin bonding (DB) agent plus a Prodigy condensable (Kerr Co.) composite, placing incremental or bulky, respectively.. In groups IK IV, V a dentin bonding agent was applied and then cavities were restored with Tetric flow composite resin as a base plus either a hybrid composite (Tetric ceram, Vivadent Co.) or a Prodigy condensable composite (Cond), placing bulky or incremental. Groups VI and VII were restored with a resin modified glass ionomer (GI) (Fuji II Lc Co.) as a base plus either Prodigy condensable or Tetric ceram. Restorations were polished, thermocycled, and immersed in 0.3% basic fushin. After that samples were sectioned and studied under a stereomicroscope to evaluate dye penetration. Results showed that all restorations showed some degree of microleakage and according to kruskall- wallis statistical analysis, there were not any significant differences between all groups (P-0.051). Then fore pair comparison, between groups. Mann-Whitney analysis was used and no statistical difference was observed. However. Gh DB- Tetric group showed the least microleakage and DB+ Cond (bulk) the most one. Due to lack of an" statistical difference among different materials methods, it is concluded that no method or restorative material have been able to eliminate microleakage in margins completely yet, and using a flowable composite resin, in place of resin modified glass ionomer or using a condensable composite, instead of conventional In brid composites, do not have any effect
N. Takzaree , K.  yarmohammadi , Ar. Takzaree , H.  semiyari. , M. Akbari ,
Volume 14, Issue 4 (1-2002)
Abstract

Pain reduction and surgical wound healing enhancement have several advantages. Wound healing is a complex and organized phenomenon. During this phenomenon, definite and harmonized processes such as: reconstruction, immigration parenchyma and connective tissue cells proliferation and re-construction of gingival connective tissue take place. Studies show that lower power laser (He-Ne) can induce different biological changes in ceils through biochemical mechanisms. Considering the therapeutic effects of (He-Ne) low power laser radiation on healing processes, cell proliferation, connective tissue fibers and finally the acceleration of gingival wound healing were studied. This study was done on 50 mature and healthy rats with the average weight of 250 to 300 grams, and 3 to 4 months old. After anesthesia, maxillary wounds, with the same size, were made in all samples and they were randomly divided into control and test groups. After surgery, rats of test group received laser radiation with the value of 5 mJ/cm3 every day for a period of 5 days. And on the 5lh day, they were killed. Gingival biopsy was performed and histological study was done. The number of fibroblasts, collagens, endothelial ceils and blood vessels were counted. In test group, the granulation tissue was more active and the edema and inflammation were lesser than those of the control group. Data were analyzed by t-test method and PO.05 was significant. So, it is concluded that periodical radiation of (He-Ne) low power laser has an important role on surgical gingival wounds.

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