JOURNAL OF ISLAMIC DENTAL ASSOCIATION OF IRAN (MAJALLAH-I-DANDANPIZISHKI)
Year:2003 | Volume:15 | Issue:3 (46)|Papers Count:10

The aim of this study was to investigate the quality of newly formed tissues after using Bio-Oss as a graft material and also to determine the level of bone regeneration and bone thickness. The incidence of inflammation and any type of forgein body reaction, following using this material was also studied. Five male sheep of the same age, race, weight and systemic condition were selected and 10 surgical defects (5x5x5mm) were created in their mandibular site. At random, one side was filled with Bio-Oss as the test group and another side as the control group, was not filled with any type of graft material. After 6 monthes, the animals were sacrificed and studied histologically and histomorphometrically. The data were analyzed by Mann-Whitney U test showing that the mean percentage of the regenerated bone and the density of the newly formed bone in the test group were statistically more than the controls (p=O.OO4).No inflammation and forgein body reaction were observed in Bio-Oss group.It is concluded that applying Bio-Oss graft material in bone defects can bear useful results. This material can also be successfully used in the procedures of sinuslift and ridge augmentation for implant placement.

The aim of the present study was to investigate the relationship between non-carious cervical lesions (NCCL) and dental premature contacts. Non-carious cervical lesions are of wedge type and their first etiologic factor is tensile and compressive stresses caused by traumatic occlusion and chewing forces. Two groups, from people referring to the Faculty of Dentistry Mashad University of Medical Sciences, were chosen. In each group 167 teeth were examined for premature contacts in centric and eccentric movements. The first group had non-carious cervical lesions, and the second group as controls were without such lesions. The results indicated that within NCCL group, the frequency of non-carious cervical lesions differed significantly among seven types of teeth, the first premolar teeth showed the greatest cervical lesions, followed by the canine teeth and the second molar had the least. Similar findings were obtained in the total number of premature contacts among the seven types of teeth. The statistical analysis revealed ahighly significant and positive correlation between the incidence of NCCL and premature contacts. The NCCL group and controls differed significantly in the number of premature contacts in centric relation (CR) and working side, but not in balancing and protrusive. There was no significant difference in the incidence of lesions between upper and lower teeth. It is concluded that dental premature contacts particularly in centrie relation (CR) and working side could affect the occurence and prevalence of the cervical lesions.

Having knowledge about the special characteristics of the impacted teeth such as type, position, depth enable the clinician to choose an appropriate treatment, better surgical method and finally to prevent surgical complications. The goal of the present study was to investigate radiographie characteristics of the impacted teeth in oral radiology department of Shaheed Beheshti dental faculty. The study was conducted through existing data on 2000 occlusal and panoramic radiographics. The data were collected through an informative questionnaire and were analyzed by statistical software (SPSS) including related descriptive statistics. The results of the study showed a prevalence of the impacted teeth about 16.7% (334 cases from 2000 ones). The sequential rate of impaction among teeth was as follows: maxillary third molars with (43%), mandibular third molars (40.5%), maxillary canine (5%), mandibular premolar (3.5%), additional teeth (3%), maxillary premolars and mandibular canines (2.5%). Impaction incidence was slightly higher in maxilla than mandible.The prevalence of the impacted teeth resulted from this study was in accordance with the rate mentioned in reference books and other studies.

The determination of DMFt index in among 12-year-old children has been accepted as a hygienic index by different sources such as WHO. The goal of this study was investigate DMFT index in 12-year-old children of Soumesara city and some of effective factors effective on it. In this analytic-descriptive study, 144 students at the 1st grade of guidence school (76 girls and 68 boys) were selected randomly and examined croos-sectionally. They were examined under natural light, using a mirror, an explorer, gloves and sterile gauze. Their general information and dental status were recorded on a special questionnair. To do statistical analysis Mann-Witney test was used. The mean value of DMFt index was 1.68±1.78 (boys: 1.44±1.64, girls: 1.96 ±1.91). 42.9% of the boys and 28.4% of the girls were caries free. The differences were not statistically significant. The economic condition of family, parents' education level, the tooth brushing habit and the frequency of dentist visit were considered to be effective factors on DMFt index although these effects were not statistically significant.Comparing to the report of DMFT index in this city in 1994 (DMFT=2.7), the results of this study manifest and improvement in this index.

The aim of this cross-sectional study was to compare the six maxillary anterior teeth, among Iranian population, with their corresponding artificial teeth available on Iran market. One hundred people, half male and half female, age ranging from 20-30 years old, were selected. Variables such as face morphology, the width, length of the central tooth and also the width of the six maxillary anterior teeth were investigated and compared with the products of 5 companies (Ideal maco, Marjan, Vitapan, Ivoc1ar, Acry Rock).The results showed that the centrals morphology can be predicted upto 76% and it should be noted that the Ideal maco products. consider face morphology more than Marjan company products. However, both companies produce teeth of smaller size than Iranian natural teeth.No proper artificial teeth. are available for relatively big size faces or those with regularsize. From among forgein companies, Vitapan and Ivoc1ar produce the most proper artifical teeth for Iranian population regarding size and morphology. It should be mentioned that AcryRock products provide us with teeth of completely proper size although Iranian face morphology have not been considered by this company.

The main of this sutdy was to evaluate the oral and dental health status of 13-15 years-old students in Rezvanshahr in 1380. In this descriptive study, the following variables, based on WHO with the examination according to WHO standards, were investigated: 1 - Extra oral examination. 2 - Temporomandibular examination. 3 - Oral mucosa. 4 - Enamel opacities/hypoplasia. 5 - Dental fluorosis. 6 - Periodontal index of the population. 7 - Dental status and treatment requirments. 8 - Dental and facial anomalies. The subjects included 300 students (150 males females), aged 13-15 years old, sampled based on probability cluster method. The results were as follows: 1 - The extra oral examination showed that 91.3% were normal and 8.7% of the subjects: were abnormal (wound, injury, other abnormalities). 2 - The temporomandibular examination showed that 89.3% were normal and atleast 10.7% had one of these signs: click, pain and decreased jaw opening. 3 - The oral mucosa examination showed that 90.6% were normal and 9.4% were abnormal (herpetic aphthaus, abscess). 4 - In hypoplasia/enamel opacities examination, 93% were normal, 3.7% had opacities with clear borders, 3% had diffused opaque points and 1.3% had hypoplasia. 5 - Fluorosis was not seen in examined sample. 6 - Periodontal examination showed that 19.88% were normal, 33.24% had gingival bleeding and 46.88% had calculus. 7 -The mean DMF and DMF were 3.55, 0.23, 0.65 and 4.43 respectively. The mean value of treatment requirement was 3.95 and the mean value for subjects without the treatment requirement was 25.05. 8 - The subjects who had lost one of their anterior teeth (incisor-canine, premolar) were 4%. 9 - 49.7% had an anterior crowding, 9.7% had a spacing in anterior segment, 6% had diastema, 39% had a malocclusion in anterior segment of maxilla, 51.7% had a malocclusion in anterior segment of mandible and 2% had anterior open bite. The mean value of the maxillary overjet was 1.09 and 0.06 had reverse overjet. 10 - Anterioposterior relation of molars were as follows: 8.7% had normal condition. 83.3% with half cusp deviation to mesial or distal side and 8% with full cusp deviation to mesial or distal side.An oral and dental health preventive program is required urgently for school children in Rezvanshar-Iran.

The increasing transmission of infections arising from blood-borne Virus such as human immunodeficiency Virus (HIV), Hepatitis B Virus (HBV) hepatitis C Virus (HCV) has resulted in detailed scruting of infection control procedures among dentists. Specific problems in infection control procedures in dental clinics vary according to the economic condition of each society. The goal of this study was to investigate infection control in dental offices of Varamin city. In this observational study, a questionnaire was formulated in three sections. The first and third sections were filled by dentist and dental assistant and the second part was filled by the questionairer. The results have indicated that 79.5% and 90.9% of the dentists used mask and gloves, respectively 64% wore protective eye spectacles. 97.9% of dnetists were vaccinated against HBV, however, 41% of them did not check their antibody levels. The knowledge level of dentists about HIV and HBV was considerable. All of dental offices had one dryheat oven and 35% had steam autoclaves. None of dentists autoclaved dental handpieces but these instruments were just cold disinfected.The findings of this study showed specific difficulties regarding the sterilization of handpieces and using autoclave. More over, infection control education for dentists and their assistants seems to be an urgent need.

The repair of an existing amalgam restoration and the addition of fresh amalgam can be a very practical alternative to the removal of the entire restoration. In such cases, in order to achieve clinically acceptable results, strong bonding strength between fresh and aged amalgam of high importance. Several factors influence this bonding such as type of amalgam, type of cavity preparation, time and the use of bonding systems. The purpose of this study was not only to evaluate the strength of 2 Iranian made amalgams (Cinalux, Cinamix), but also to determine the fracture streng th of the fresh to aged amalgam bonding. Standardized class II preparations (Mo or Do) were placed in 120 teeth. Specimens were divided into 6 groups as follows: Group 1: Specimens were filled with spherical amalgam. (Cinalux). Group 2: Specimens were filled with admixed amalgam (Cinamix). Group 3: Specimens were filled with spherical amalgam, after 1 hour Proximal part of filling was completely removed and freshly triturated spherical amalgam was condensed against the surface to be repaired. Group 4: The same as Group 3, but in this group mixed amalgam was used. Group 5: After 1 hour, proximal part of filling was completely removed and alloy bond was brushed on the amalgam surface to be repaired and filling was completed with spherical amalgam. Group 6: The same as Group 5, but in this group, mixed amalgam was sued. In each group, half of the specimens 48 hours and the other half 30 days after repair were stressed under compression load until fracture occurred. The fracture strength was measured by kruska wallis and Mann- Whitney U statistical tests. No statistically significant difference was found between different types of amalgam (spherical, admixed) in the fracture strength of repaired CLlI amalgam fillings (P>0.05). In addition, the use of amalgam bonding was not a significant factor (P>O.05). No statistically significant differences were observed in keeping samples in distilled water (2 days vs. 30 days). However, the results indicated considerable decrease in fracture strength after 30 days in all groups. Teh results of kruskal-wallis test also showed no with spherical amalgam after 48 hours (P=0.32) and groups repaired with mixed amalgam (P=0.51). The same results were found after 30 days for spherical amalgam (P=0.6) and mixed amalgam (P=0.33). The Following conclusions can be drawn from this study: 1 - Fracture strength of repaired (with or without amalgam bonding) clII amalgam filings is comparable to unrepaire fillings. 2 - Type of amalgam is not a significant factor in the repair strength ofamalgam filling.3 - After 30 days, fracture strength of repaired filling may decrease comparing to that of after 2 days.

Root conditioning treatmnt techniques (In vitro) has led to satisfactory results. Few clinical investigations has been conducted on this method combined with connective tissue graft. The purpose of this study was to clinically evaluate the mean root coverage with and without tetracycline HCL root conditioning with subpedicle connective tissue graft (SPCTG). 15 patients (mean age 48) with bilateral 30 Miller's class I gingival recessions participated. In each patient at random, one recession defect was treated with full thickness SPCTG procedure combined with tetracycline H'CL root conditioning (test group) and the other recession defect just received the SPCTG procedure (control group). Recession height (RH), recession width (RW), probing depht (PD), gingival width (GW), and clinical attachment level (CAL) were measured at baseline and 3 months postoperatively. Papillary width (PW) and height of osseous dehiscence (HOD) also were measured. Intra and inter group changes in these clinical parameters were analyzed statistically. Autocad software was used to measure the level of root coverage. The mean root coverage (RC) and mean surface coverage (SC) in test 2 2 and control groups were 99%, 97%, 11.83±2.62 mm2 and 6.78±1.36mm2 and the differences between two groups were significant (P<0.05). Complete RC in test and control groups were 86% and 53.3% respectively. The mean changes in RH, RW, GW and CAL in each group were significant (P<0.05). However, between two groups these changes were not significant (P>0.05) Reduction of PD in test group was not significant (P> 0.05) but in control group was significant (P<0.05). RH was directly correlated with the mean RC in both groups (P<0.05) The mean RW, HOD and PW were not correlated with mean RC in two groups (P>0.05). Reduction of sensitivity to air syringe in test group after surgery was significant (P<0.05) but in other group was not (P=ns). However sensitivity to explorer in both groups was reduced 3 months after surgery, the differences were not significant (P=ns).Better results in respect to mean RC, mean SC and also 86.7% RC in test group comparing to 53.3 in control group may be a reflection of desirable effects of tetracycline HCL root conditioning in these procedures and encourage other clinicians to apply this chemical substance.