Journal of Dental Medicine

Normal 0 false false false EN-US X-NONE AR-SA One of the concerns od patients have been teeth stains particularly in anterior region. The etiology of this can be pulp necrosis, developmental disorders, drugs and systemic diseases. Bleaching or tooth whitening is a solution for some of these color changes. This article evaluated different methods of bleaching and their side effects . In case in which tooth whitening is needed,  attentive case selection should be done and advantages and disadvantages of each method should be considered in order to apply the best treatment among other options of bounding, veneering or crowning.

Normal 0 false false false EN-US X-NONE AR-SA 1482 patients of 3-5 years ( 56% m/44% f) were selected from Isfahan kindergartens. In 1.4% of them, numeric  dental anomaly was diagnosed of which 0.74 %  had congenital missing teeth, 0.06 % had hyperdontia and 0.6% had geminated teeth. 0.72 % of Congenital missing was seen in boys while 1.2% in girls. Also, Gemination was seen 0.12 % in boys and 1.2% in girls which is 10 times more than boys in total study population. 0.2% of cases had concomitant tooth missing and gemination. Missing was mostly seen in mandibular incisors. Germination was seen  80% in mandibular anterior region. Besides, in 50% of the patients who had primary teeth missing, permanent teeth missing in both sides were also diagnosed by radiography. One case found with supernumerary tooth in maxillary lateral incisor region. In this article, the possible risk factors were analyzed in case and control groups. Any significant relationship between these factors and numeric dental anomalies was concluded.

  There is lack of consensus among endodontic specialists about the necessity of tug back. In this regard, we designed a study in which 44 single rooted teeth with closed apex were selected and filed up to file #50. The teeth were obturated with lateral condensation method while in half of them there was not any tug back and in the other half tug back was achieved. Apical leakage was assessed by color infiltartion via microscope. The obtained results showed significantly lower infiltration in tug back group which leads to a direct relation between tug back and color infiltration although due to statistical analysis, this relationship was not reliable and needs further proofs.

Statement of Problem: There is a controversy about the relationship between pulpal and periodontal diseases. The interrelationship between pulp and periodontium could have an important effect on the treatment plan of the tooth.

Purpose: The aim of the present research is to evaluate root canal therapy effects on periodontal healing of teeth with chronic advanced periodontitis.

Materials and Methods: In this randomized controlled clinical trial 32 single rooted teeth which had necrotic pulp or irreversible pulpitis in 7 patients with chronic advanced periodontitis were selected based on specific criteria. Using a split mouth design, teeth were randomly put in two groups of test and control. In the test group root canal therapy ,scaling & root planing were done.In the control group, only scaling & root planing were performed. Clinical parameters including Pocket Depth (PD), Clinical Attachment Level (CAL), mobility, pattern of bone destruction and plaque index (PI) were evaluated in two groups at base line, 1 and 3 months after treatment. Appropriate tests such as paired Wilcoxon and Mann-Whitney were performed.

Results: Statistically significant reductions were found in the test group when comparing baseline and one-month post treatment values for Clinical Attachment level (CAL) but not after 3-months. In the control group the CAL reductions were not statistically significant between baseline and one month post-treatment, but a increase were observed between one month and three months after treatment. There was a statstically significant difference between the test and the control groups. Other parameters didn’t show any significant differences in each group and between two groups.

Conclusion: Since clinical attachment level was the most important parameter we found it can high lighted the role of pathogene with pulpal origin in progression of periodeontal disease and it is concluded that beside periodontal treatment in some advanced periodontal cases pulp therapy maybe an effective procedure for eleminating destructive pathogens of pulp and causing periodontal healing.

Background and Aim: Aggressive periodontitis is one of the periodontal diseases, which affects systemically healthy individuals usually under the age of 30 years old. The disease is characterized by rapid bone destruction which is not in accordance with the quantity of bacterial plaque. The purpose of the present study was to determine the prevalence of aggressive periodontitis among 15-18 years old female students in Tehran high schools.

Materials and Methods: In this cross sectional study, , 2870 students were selected from all educational areas of Tehran during 1382-83 based on systematic clustered random sampling .Probing pocket depth on 6 areas of incisors and first molars were examined in each subject. Students with pocket depth equal to or more than 4 mm on more than one tooth were referred to Shahed Dental School for radiographic examination. For cases in which the distance between the crest of interdental septa and CEJs were equal to or more than 2 mm, full clinical and radiographic examination was performed.

Results: Among the subjects of study, only 4 fulfilled the diagnostic criteria of localized aggressive periodontitis. Nobody was diagnosed with generalized aggressive periodontitis. The prevalence of aggressive periodontitis among 15-18 years old schoolgirls was 0.14%.

Conclusion: The results of the present study were similar to previous studies with the same age groups and diagnostic criteria in other countries. For determination of total prevalence in Tehran, similar studies in schoolboys are recommended.

Background and Aim: Many studies have shown that microorganisms are the main cause of pulpal diseases and the main purpose of root canal therapy is their elimination from the root canal system. Antiseptic agents are used to reduce bacteria but their antibacterial activities differ from in vivo to in vitro studies and might be inactivated by dentin and its components in root canal space. This study was designed to investigate the effect of dentin on antibacterial activity of different antimicrobial agents.

Materials and Methods: In this experimental study, two antibacterial agents (sodium hypochlorite and chlorhexidine) with different concentrations were used in four experimental groups: Group 1: dentin, Group 2: demineralized dentin with EDTA, Group 3: dentin matrix and Group 4: dentin mineral component. The species used in this study was Entrococcus faecalis. Different concentration of agents were added to mixture of each experimental group and bacteria. At the baseline and after one and 24 hours, samples were collected and cultured. After incubation period, colonies were counted. Data were analyzed by Tukey test with p<0.05 as the limit of significance.

Results: 2% and 0.2% chlorhexidine, and 5% sodium hypochlorite solutions at the three studied times eliminated Entrococcus faecalis completely. 1% sodium hypochlorite eliminated all bacteria in 1h and 24 hs. Statistical analysis showed significant differences between experimental and control groups (P<0.05). Sodium 1% hypochlorite at time 0, could reduce bacteria significantly (P<0.05) but didn’t eliminate them completely.

Conclusion: Inactivation of intracanal antiseptics was not observed in this study. As elimination of bacteria occurred, application of these antibacterial agents are recommended in endodontic treatment. Further investigations on other antibacterial agents, other concentrations and shorter time intervals are recommended.

Background and Aim: Application of varnish and dentin bonding agents can effectively reduce microleakage under amalgam restorations. Also rebonding may show some effects on microleakage and its complications. The aim of this study was to evaluate the effect of liner/ adhesives on microleakage of Class V amalgam restoration with or without rebonding.

Materials and Methods: In this in vitro study Class V cavities were prepared on sixty sound human maxillary premolars with the gingival floor 1mm below the CEJ. Cases were divided into six groups of ten teeth each. Specimens in group 1 and 2 were lined with Copalite and Scotchbond Multi-Purpose (SBMP) respectively. In the third group (control) no liner was applied. The teeth were then restored with spherical amalgam. Specimens in group 4 to 6 received the same treatments but after filling, the interfaces of restorations and teeth were etched with 37% phosphoric acid gel, rinsed and dried. Adhesive resin of SBMP was applied over amalgam and tooth margins and polymerized (rebonding). Specimens were thermocycled, exposed to dye and sectioned. Microleakage was graded (0-3) using a stereomicroscope at X40 magnification. Data were analyzed with Kruskal-Wallis, Mann-Whitney and Wilcoxon pair wise statistical tests. P<0.05 was considered as the limit of significance.

Results: The groups lined with SBMP showed the lowest and the groups without liner the highest microleakage (p= 0.001). Significant difference was observed in microleakage mean rank of enamel and dentin margins (p=0.048). Rebonding with resin did not improve the seal (p> 0.05).

Conclusion: Based on the results of this study, total etch adhesive system had significant effect on microleakage of Class V amalgam restorations especially in cervical margin. Rebonding did not show a significant effect on microleakage.

Background and Aims: Adequate retention of the post is a prerequisite for the clinical success which might be affected by the type of root canal filling material. The aim of this in vitro study was to compare the effects of gutta-percha and Resilon on retention of quartz fiber posts.

Materials and Methods: In this experimental study, 44 maxillary central incisors were sectioned at the CEJ level and prepared endodontically using ProTaper rotary files. The specimens were then randomly assigned into two experimental groups (n=22): group R, the root canals obturated with Resilon and group G, the root canals obturated with gutta-percha. After preparing the post space and insertion of quartz fiber posts, the coronal 10 mm of the root was sectioned perpendicular to the long axis to produce disks of 2.3 mm thickness.Then the specimens were submitted to the push-out test (1mm/min) using a universal testing machine. The data were analyzed using Mann-Whitney U test.

Results: There was a significant difference between the retention of posts in groups R (7.08±5.1) and G (4.8±3.3) (P=0.04).

Conclusion: Quartz fiber posts showed significantly higher retention in teeth obturated with Resilon compared to those obturated with gutta-percha.

Background and Aims: There is concern that leached components from dental composites may cause adverse changes in the reproductive health. This study aimed to assess the effects of leached components from a hybrid resin composite on the reproductive system of male mice.
Materials and Methods: In the present animal study, twenty adult Syrian male mice were divided into two groups of 10 mice each. In the test group, components which leached from samples made from Filtek Z250 resin composite into 75% ethanol were daily administered to the mice for 28 days. In the control group, the procedure was repeated in the same way as the test group but without placing composite samples in the solution. Then, the body weight, weights of paired testes, Gonado Somatic Index, sperm viability, sperm motility, epididymal sperm reserve and daily sperm production were recorded. Four male mice in each group were mated with untreated female mice for 10 days. After that, the number of pregnant females and number of infants were recorded. The data were analyzed using repeated measures ANOVA, Chi-square test and t-test.
Results: There was a significant reduction in the sperm viability and sperm motility of male mice in the test group compared to the control group (P=0.001). There was no any significant differences in other parameters between two groups (P>0.05).
Conclusion: This study showed that the leached components from resin composites cannot cause infertility but they could potentially cause some adverse effects on the reproductive system of male mice.

Background and Aims: Regarding the diversity of reported low- back pain among dentists in different countries and lack of control group in most of the previous studies, the purpose of this study was to compare low- back pain and related risk factors between male general dentists and pharmacists to determine the relation between dentistry and development of low back pain.

Materials and Methods: In this cross-sectional study, 261 male dentists were compared with 193 male pharmacists as a control group with Standardized Nordic Questionnaire (low back section). Subjects were at least one year in clinical practice after becoming qualified and did not suffer from connective tissue diseases and history of a traumatic event causing fracture in spinal column. The data were analyzed by Chi- square, T-test and logistic regression analyses.

Results: The prevalence of low back pain in the past 12 months was 54.8% in male dentists and 36.3% in male pharmacists (P=.001). Logistic regression analyses, adjustmenting for occupation, age, body mass index (BMI), smoking, working years and working hours per week, revealed that there was a significant association between being a dentist and having low- back pain (OR=2.54, P=0.001).

 Conclusion: Dentistry as a profession in male gender is associated with low back pain, independent of age, body mass index (BMI), smoking, working years and working hours per week.

  Background and Aims: Oral health prepares us for daily activities without discomfort, and dissatisfaction. In this research, agreement level between parents and children aged 11-14 year-old in reporting child oral health-related quality of life was studied in Isfahan city.

  Materials and Methods: In this descriptive, analytical and cross-sectional study 128 pairs of parents and children aged 11-14 were selected with random sampling technique from schools in Isfahan and were asked to complete the relevant questionnaires. The questionnaires evaluated quality of life in four fields of oral signs, functional deficits and emotional and social health. In order to evaluate child-parent agreement, intra-correlation coefficient (ICC), Pearson’s correlation coefficient, Spearman’s correlation coefficient and intra-class correlation coefficient (ICC) were used (α=0.05).

  Results: The agreements between PPQ_11-14 (parent perception questionnaire), CPQ_11-14 (child perception questionnaire) and the related fields were 0.81, -0.67. The highest agreement level (ICC=0.83) was related to emotional health (excellent), followed by functional deficits (ICC=0.80), social health (ICC=0.69) and oral signs (ICC=0.64). Pearson's test showed significant correlations between CPQ_11-14 and PPQ_11-14 (r=0.81) (P<0.01).

  Conclusion: Although parents, especially mothers, may be used as proxies for their children in relation to quality of life and related fields, the views of both should be obtained in order to fully represent child oral health-related quality of life issues.

  Background and Aims: Successful root canal therapy requires knowledge of tooth anatomy and root canal morphology. For permanent mandibular premolars, great variety in size, shape and number of roots and root fusion expression has been reported in the literature. There is a wide variety of methods used in studies for evaluating the root canal morphology. One of these methods is Cone-beam Computed tomography (CBCT) that reduces the limitations of two-dimensional X-ray imaging, with less exposure in comparison with other 3D radiographies. Thus, this study was designed to evaluate the differences in the root and canal morphology of permanent mandibular premolars in an Iranian population by means of CBCT images.

  Materials and Methods: We searched a database of CBCT scans and evaluated 400 (20-60 years old) patients who met the inclusion criteria and teeth in this images (CBCT) were evaluated in three dimensions (Axial, Coronal and Sagital). Tooth length, number of roots, number of canals, canal type, root curvature and the effect of gender on any of the items mentioned were evaluated. Data were analyzed using T-test.

  Results: The average length of the first premolar of mandibular was 22.27 mm and second premolar was 22.28 mm. 98.4% of the first premolar and 98.2% of the second premolar were single root., and 87.3% and 93.1% were single channel. The incidence of number of canals based on vertochy divisions were:type 1: 90.7% and 90.8%, type 0: 2.2% and 2.8%, type 4: 3.3% and 3.1%, type 6: 1.4% and 2.1% and type 3: 2.5% and 1.5% respectively. In any case, there was no significant difference between males and females (P<0.001).

  Conclusion: Results indicate that dentists can obtain valuable information about the anatomy and morphology of the root canals using CBCT.

  Background and Aims : The root fracture resistance of endodontically treated teeth depends on the types of posts. The aim of this study was to compare the effect of two types of bonded non-metallic posts with different elasticity modulus on the fracture resistance of endodontically treated teeth under compressive loads.

  Materials and Methods: In this in vitro experimental study, 20 fresh extracted mandibular premolars were selected and sectioned adjacent to the CEJ and then were endodontically treated. The specimens were randomly divided into two groups (n=10). After post space preparations, the fiber RTD Light posts (R.T.D, France) and zirconia coated fiber posts (ICE light, Danville) were cemented into the root canals. Composite resin (Lumiglass R.T.D, France) cores were built up. Aluminium foil was used to mimic the PDL, and the specimens were embedded in acrylic resin and tested in a Universal Testing Machine. A compressive load was applied at a 90 degree angle until fracture at a crosshead speed of 1mm/min. Data were analyzed using one-way ANOVA and T test .

  Results: The mean fracture resistance of R.T.D group was (1083.11 ± 156.74 (N)) and the mean of ICE light group was (865.18 ± 106.24 (N)). The highest mean fracture resistance was observed in RTD fiberglass and a statistically significant difference was observed between the two groups (P<0.001).

  Conclusion: FRC posts with zirconia coating due to unfavorable fractures of the teeth should be used with caution, and thus, fiber posts are preferred.

  Background and Aims: Hepatitis B is an important infection route in dentistry requiring different disinfectants to prevent its transmission. The aim of this study was to compare the effects of chemical disinfectants (FD366, ISORAPID and 5% sodium hypochlorite 2/100) to remove Hepatitis B infections from the dental surfaces.

  Materials and Methods: In this experimental laboratory trial, serum of 10 HBV patients was poured into microtubes, FD366, ISORAPID and hypochlorite disinfectants were added to them. PCR experiments with viral diagnostic kits were used to diagnose the virus genome. Real time PCR was used to evaluate after incubation with the disinfectants. The reductions occurred in the viral load of Hepatitis B were statistically analyzed using Kruskal-wallis and Mann-Whitney U tests .

  Results: No significant antiviral efficacy was noted following the application of FD366 and ISORAPID disinfectants (P=0/07). However, hypochlorite showed the most efficacy to disinfect Hepatitis B and a significant difference was found among them (P<0.0001).

  Conclusion: Under the study limitations, FD366 and ISORAPID disinfectants did not show adequate efficacy to remove Hepatitis B virus. Hypochlorite was the most effective disinfectant.