Journal of Dental Medicine

Background and Aims: Dental caries is the most common infectious diseases. Among the oral bacteria, Streptococcus mutans and Streptococcus sobrinus are considered as the main causes of tooth decay. The aim of this study was to evaluate the production of hyperimmune bovine colostrum containing specific antibodies against cariogenic bacteria and its antimicrobial effects on the growth and adhesion of Streptococcus mutans and Streptococcus sobrinus in the laboratory.

Materials and Methods: In this experimental study, three pregnant bovine immunized with killed antigens of strains of Streptococcus mutans, Streptococcus mutans with Streptococcus Sobrinus and Streptococcus sobrinus through intramuscular injections. After delivery, The colostrum samples were collected, and the changes of anti-streptococci antibodies titers in colostrum and serum were determined by agglutination. Also,their antimicrobial effects against the growth and adhesion of oral streptococci were surveyed by the microtiter plate method. Data were analysed by One-Wey ANOVA in SPSS software.

Results: The results showed that in hyperimmunized bovine , the antibodies titers against injected bacteria were from 1.1000 to 1.3000 in sera samples and from 1.320 to 1.1280 in whey of colostrum samples. Colostrum of hyperimmune cows reduced the attachment of Streptococcus mutans and Streptococcus Sobrinus about 69 and 43 percents, respectively and also, the low dilutions of it reduced bacterial growth.

Conclusion:  According to the antibacterial effect immune colostrum on two strains of cariogenic bacteria in vitro, It appears that this material could be useful in the prevention and control of dental caries.

Background and Aims: The purpose of this study was to evaluate the relationship between the mandible anatomy with age and gender in panoramic radiography of patients.

Materials and Methods: In this descriptive-sectional study, 322 panoramic radiography of patients at the age of 25-55 years old were evaluated. The patients were devided in three groups of 25-34, 35-44, 45-55 years old and the radiomorphometric indexes in panoramic radiography of the patients were measured. The collecting data were analyzed using independent two-sample t-test, one-way anova and multiple linear regression using SPSS statistical software (version 18).

Results: The average of radiomorphometric indexes don’t show a meaningfull statistical defference between different age groups. The average of all angles higher in females than that of males and other measured indexes were higher in males than females. Also, the mandibular foramen moved forward with the increase of age.

Conclusion: Based on the result of this study which was done on limited numbers, it can be concluded that the measured radiomorphometric indexes in this study didn’t have a high accuracy to predict Age and Gender.

Background and Aims: Traumatic dental injuries (TDIs) are of the most common dental problems in children and adolescents, which usually occur in the anterior segment and have a significant role in patient’s physical and psychological health. Immediate intervention for damaged teeth can elevate the success rate of treatment in TDI. Thus, general dentists’ knowledge and their effective intervention in TDI are important factors in prognosis of traumatized teeth. The objective of this study was to assess the general dentists’ knowledge and awareness regarding the diagnosis and management of traumatic dental injuries.

Materials and Methods: In this cross-sectional study, the questionnaire data were collected from 130 general dentists, including the demographic data and general dentists’ knowledge about TDIs. The data were analyzed using the Student t-test and Analysis of Variance (ANOVA), Spearman’s and Pearson’s correlation coefficient.

Results: The mean score of general dentists’ knowledge was 8.5 ± 1.5 (total score:10) and it was the same between both males and females (P=0.083). Dentists’ work place does not have any influence in their knowledge (P=0.133). Also, there was no statically significant relationship between the age, job experience and dentists’ knowledge (P=0.805). The relationship between the frequency of TDI managed cases and dentists’ knowledge was not significant (P=0.507).

Conclusion: Considering that the overall knowledge of general dentists regarding the management of TDI was sufficient, it could be a good opportunity in treating these injuries. As TDI is a developing science, it is important to motivate general dentists being up to date regarding this matter.

Masticatory muscle pain is the second most frequent cause of orofacial pain after dental pain. Myofascial pain dysfunction syndrome (MPDS) is the most common form of temporomandibular joint dysfunction. MPDS is a pain that triggers from [sensitive] points in the muscles and fascia and is followed by spasm, tenderness to palpation, restricted movement, fatigue, and sometimes dysfunction. The researchers intended to collect comprehensive information about therapeutic interventions for myofascial pain through the conduction of a critical study based on evidence in the literature. In this review, 51 English articles, published between 1981 and 2013, were extracted from PubMed, Medline, Ovid, and Google Scholar. These articles were then reviewed in detail in two categories, namely pharmaceutical and non-pharmaceutical treatments. MPDS treatment should be first focused on the identification and correction of underlying causes. Thiocolchicoside (TCC), non-steroidal anti-inflammatory drugs (NSAIDs), and Cox-2 inhibitors are among promising pharmaceutical methods. On the other hand, ultrasound and laser therapy are among promising non-pharmaceutical methods. The complex mechanism of MPDS, along with its underlying peripheral and central nervous mechanisms may make MPDS, difficult to treat, especially in its chronic form.

Background and Aims: Delay in light irradiance can improve the polymeric structure and mechanical properties of resin cement and uniform stress distribution. The aim of this study was to evaluate the effect of light activation modes (immediate, 5 and 10-minute delay) on the push-out bond strength of cemented fiber posts with two types of resin cements in different of root canal regions.
Materials and Methods: In sixty extractedsingle canal and endodontic therapied roots, FRC Postec Plus were cemented with two resin cements, Nexus3 and Panavia F2.0, in three curing methods, immediate, 5, and 10 minute delay. After 24 hours storing in a dark place, they were cut into three sections: coronal, middle and apical. The push-out bond strength test was performed using the universal testing machine. Failure modes were evaluated using stereomicroscope. Data were analyzed by ANOVA and Tukey post hoc test with P<0.05 as the level of significance.
Results: In Nexus3, the immediate light curing had significantly higher bond strength (11.18±4.32) than delay methods (P=0.001). In Panavia F2.0, the 5-minute delay had significantly the highest bond strength (13.34±4.62) (P<0.05). There was no correlation between the different light curing methods and root canal regions. In Nexus3, the coronal region had higher bond strength (11.83±3.7) than that of middle (9.12±3.1) (P=0.015), and middle than of apical (5.65±2.77) (P=0.00), and coronal than that of apical (P=0.002). In Panavia F2.0, there were not significant differences among regions (P>0.05).
Conclusion: Delay in light curing of dual-cure resin cement's had different effects on the push-out bond strength.
 

Background and Aims: Cancer is the second most common cause of death in developed countries. The goal of this study was to determine the important epidemiologic factors affecting diagnosis and survival rate of patients with laryngeal SCC, for prevention, control and increase longevity.
Materials and Methods: In this study, all the cases recorded at the Center of Cancer Office of the Iran Ministry of Health in Tehran between 2005-2009 were examined. From 513 cases, 279 that their follow-up was possible by phone or postal address were included in the study. Data collection were performed from questionnaire. The data were analyzed by SPSS version 20. The Kaplan Meier survival curves were utilized and, moreover, the corresponding influential factors were examined by using the Cox regression test.
Results: The mean age of patients were 61.1 years (SD=10.54). The gender of 92.1% of patients were male. The most widely used method for the treatment was a combination of three methods of surgery, radiation therapy, and chemotherapy. The overall five-year survival rate was 75.7% (SD=0.03). The gender, histological differentiation, and professional delay did not exhibit a statistical correlation with the survival rate (P=0.38, 0.14, 0.52), whereas the age and patient delay had a statistically significant relation with the survival rate (P=0.03, 0.07).
Conclusion: The survival rate was lower in older patients. Patient and professional delays were high, which need more attention for improving the quality of life.
 

Background and Aims: To create a good adhesion between porcelain veneers and zirconia restorations has been important issues is the prosthesis. The aim of this study was to identify an effective way to prepare the zirconia surface infrastructure to increase its shear bond strength to the porcelain veneer.
Materials and Methods: 75 samples of zirconia (Y-TZP) cylinders (diameter of 7 mm and a thickness of 3 mm) were fabricated. Based on the surface treatment, specimens were randomly divided into 3 groups: control, air abrasion and
Er-YAG laser. After surface treatment, the specimen surfaces were examined by SEM. Using a metal mold, the porcelain was veneered on the zirconia surface and then fired. After thermocycling, the shear bond strength of porcelain to zirconia was measured and then the failure mode of each specimen was analyzed using a stereo-microscope. Data were analyzed by one-way ANOVA and Tukey test.
Results: Significant differences were observed between the mean shear bond strength of different groups (P=0.001). The greatest amount of shear bond strength was observed in the group (S) and the lowest bond strength in the control group. Analysis of failure modes showed no statistically significant difference in the type of failure among study groups. The adhesive failure was predominating failure at the intersection of porcelain veneers.
Conclusion: The highest shear bond strength between zirconia and porcelain was achieved by sandblasting the zirconia surfaces compare with that of Er_YAG application.

Background and Aims: Marginal gap measurement in all ceramic restorations they are of fundamental important for the successful used. As some studies led to contradiction results, yhe aim of this study is to compare marginal gap restorations between 4 kinds of ceramic restorations Inceram, IPS-e.max Press, Zirconia (CAD/CAM) and PFM.
Materials and Methods: In this In-vitro experimental research, one stainless steel die with deep chamfer finish line design (1 mm depth) was prepared on a maxillary premolar. 40 epoxy resin dies were made, dies were divided in to 4 groups (n=10), Zirconia, IPS e.max press, Inceram, Mental Ceramic systems (MC). Then, the prepared crowns were put on the stainless steel die and observed their marginal mismatch under sterio microscope before cementation. Data were analyzed by One- way ANOVA, and one sample kolmogorosmirnov tests.
Resultes: There was significant difference in the marginal gaps between (MC) (102.92±28.7), Inceram (98.41±24.91), IPS e.max press (128.22±25.48), and Zirconia (69.5±10.9) (P=0.0001).
Conclusion: The comparison of marginal gap for the four groups was significant test. Therefore, it can be concluded that marginal gap, the probability of leakage and recurrence of caries in Zirconia systems is the least and in the IPS e.max press systems is the most.

FTIR spectroscopic imaging is a chemical imaging method that can be employed to a broad range of applications. This powerful technique is suitable for determining the functional groups and chemical structures of the samples. The advantage of infra-red spectroscopy is that it can be used for various modes of physical samples. The aim of the current paper was to review the recent advances and the potential uses of Fourier Transform Infra-red Spectroscopy in dentistry via exploring related literature during 1960 till 2017 in Science Direct and PubMed databases. One of the most popular applications of infrared spectroscopy is to calculate the degree of conversion in the resin based dental materials. It has also been used to investigate the chemical structure of the teeth and bones, synthesis calcium phosphate, the diagnosis of microorganisms, and pathological conditions. In this paper, we mentioned the principles of this technique and recommend this method as a simple and fast way to determine the structure of the materials and their alteration.

Background and Aims: In 1978 WHO (World health organization) formulated a histopathological definition for diagnosis of OLP (oral lichen planus). Previous studies showed that diagnosis of OLP with these criteria are not reproducible. In 2003 Van der Meij et al. represented new clinical and histopathologic definition for diagnosis of OLP known as modified WHO criteria. The purpose of this study was to evaluate the interobserver and intraobserver variability in the histopathological assessment of OLP based on the modified WHO criteria.
Materials and Methods: Fifty five microscopic slides which OLP and OLL (Oral Lichenoid Lesion) were recognized in their clinical differential diagnosis were given to 6 pathologists in two phases with 3 months interval. Each reviewing pathologist was asked to apply the modified WHO definition of OLP and to categorize each case as either OLP, or compatible with OLP. Then, the interobserver and intraobserver variability were assessed by calculation of repeatability coefficient and Kappa statistics.
Results: The results of this study demonstrated that interobserver variability based on modified WHO criteria was 0.77 (strong), while the intraobserver variability varied from 0.58 (moderate) to 0.82 (strong).
Conclusion: In the present study, the interobserver and intraobserver variability in the histopathologic assessment of OLP based on modified WHO criteria was stronger than previous studies which assessed WHO criteria. However, in order to propose the replacement of WHO criteria with modified WHO criteria, further studies with more cases and comparing the two methods is required.

Background and Aims: Despite their ascribed intellectual ability and achieved academic pursuits, the dental student’s academic achievement is influenced by learning motivation. This study in an Endeavour aimed to examine the learning motivation factors of dental students of Rafsanjan University of Medical Sciences.
Materials and Methods: In this descriptive-cross sectional study, 120 dental students completed the questionnaire which comprised of 33 questions regarding intrinsic and exogenic motivational factors. Demographic factors (gender, marital and native status, employment year of study) were examined. Data were analyzed by SPSS17 software. Descriptive and analytical statistical methods (t-test, Pearson correlation and ANOVA statistical tests) were used.
Results: The mean of the achieved scores in the domains of learning motivation was 2.98±0.32 out of 5,which was considered as moderate level. Comparing the means of the intrinsic (3.16±0.48) and exogenic
(2.82±0.44) domains showed significant differences (P<0.05). Correlation between the intrinsic motivation domain and elements of exogenic motivation domain with academic achievement were not significant (P=0.62). Total score of Intrinsic and exogenic motivation is higher in male and non-native students.
Conclusion: Educational motivation of Rafsanjan dental students was moderate. In learning, intrinsic motivational factor was more than exogenic factors in male students.

Background and Aims: In recent years, the dentistry workflow has developed considerably. By the introduction of computers and their various applications, the effectiveness and efficiency of treatment has increased enormously. Considering engineering concepts in the workflow, it is necessary for participants to assess different steps and data transferring between various software and hardware devices. This research investigated the interaction between dentists, laboratories and production centers through the required steps for accomplishing treatment by different applications of software and digital hardware devices.
Materials and Methods: Review in this article was based on searching Google scholar database considering key words: digital dentistry, workflow, computer aided design and manufacturing, dental CAD/CAM. This search was limited to the English articles published after the year 2000.

Conclusion: It is necessary in dentistry to use digital technologies to improve the efficiency of treatments. Thus, the participants in this field must have appropriate knowledge to choose and apply these tools. Moreover, the participant should help providers of digital solutions for better development of software packages and related hardwares.a

Background and Aims: The structural distinction of primary teeth compared to the permanent teeth leads to a faster penetration of the caries into the pulp, which makes effective treatment necessary. The aim of this study was to determine the success rate of pulpotomy in primary molar teeth and its effective factors using formocresol by students and residents at the department of pediatric dentistry of Hamedan dental school.
Materials and Methods: In this cross-sectional study, 113 children who previously had pulpotomy by formecresol in their primary molars (30 children by residents and 83 children by the students) were randomly evaluated based on referral time (at least 12 months after treatment) in terms of clinical and radiographic success rates. Data were analyzed by SPSS20 software using Chi-square and descriptive statistics.
Results: The success of the pulpotomy of primary molar teeth was 81.7%. The success rates of the general students and residents were 79.3% and 87.3%, respectively. The percentage of successful pulpotomy was significantly higher in general students at Stainless Steel Crown (S.S.C), second molar in maxilla (P<0.05), but did not have a significant relationship with age and sex (P>0.05). The percentage of pulpotomy success performed by residents did not have a significant correlation with gender, age, type of repair, type of teeth and jaws (P>0.05). In general, the percentage of success in S.S.C, the second molar and maxillary jaw was higher. Also, the success rate of pulpotomy by residents was significantly higher than that of general- students (P<0.05). The highest rates of pulpotomy failure were related to internal analysis.
Conclusion: Formocresol pulpotomy using S.S.C in the maxillary second molar teeth had higher success rate.

Background and Aims: Caregivers’ oral health literacy (OHL) can be effective in increasing their children’s knowledge, and can improve their oral health-related behaviors. This study aimed to investigate the relationship between mothers’ OHL and children’s oral health status.
Materials and Methods: We conducted a cross-sectional study on 202 6-year child/mother dyads in Semirom, Iran, applying a cluster sampling method. Self-administered questionnaires (Oral Health Literacy-Adult Questionnaire) requested information about mothers’ OHL. Children’s oral health status (dmft and pufa) was recorded via clinical examination. Pearson correlation coefficient, spearman correlation coefficient, independent T-test, and a linear regression model were used for statistical analysis.
Results: Among 202 pre-school children, 99 were girls (49%). The mean OHL score of mothers was 63.2 (Max achievable score=100, SD=18.9). Higher score of OHL among mothers was associated with their children’s less missing teeth (mt) and more filled teeth (ft) (P<0.05). No significant the association existed between the mothers OHL and their children’s dt, dmft, and pufa. Childrens of younger mothers, more educated mothers, and those with better oral health behaviors in terms of daily flossing and tooth brushing, showed lower scores of dmft and pufa (P<0.05).
Conclusion: A significant association revealed between mothers’ OHL and the oral health status of their children. Thus, it is recommended to increase mothers’ OHL to improve their children’s oral health status.

Background and Aims: Color is the most important and complicated part of aesthetic dentistry. The tooth color matching of restorations is considered as one of the most difficult tasks in the restorative dentistry. The aim of this study to evaluate the effect of two training methods on the dental students’ ability in determining tooth color matching.
Materials and Methods: In this study, 40 dentistry students participated which randomly allocated into two groups. The first group consisted of students who learned teeth color matching methods practically. In the second group, training booklet was used for learning. Using Vita Classic shade guide series, 4 color samples were chosen and the students of each group were asked to determine samples’ color, before, after and one month after the training.
Results: Booklet learning group was more successful in determining fourth color sample. However, in no studied group and no used samples, the results of one month after learning were not better than that of before learning. Also generally, no significant relationship was found between the color matching accuracy, using glasses, and sex of participants.
Conclusion: The use of booklet learning was more effective than practical learning in color matching accuracy for dental students. Also, using glasses and sex were not effective on their color matching accuracy.

Background and Aims: Methicillin-resistant Staphylococcus Aureus (MRSA) is an important infection source in dentistry for different disinfectants to be used to prevent its transmission. Furthermore, a variety of chemical disinfectants are developed to remove bacterial infections from the dental care workers' hands and claims are made regarding their superiority in infection control, although all requires scientific investigations. The aim of present study was to compare the effects of chemical hand-disinfectants Micro Zed HD, Aseptoman and Decosept on MRSA (methicillin resistant staphylococcus aureus) in different periods of time.
Materials and Methods: In this experimental study, the antibacterial efficacy of three hand-disinfectants on standard strain of MRSA (USA300: ATCC® BAA-1717™) was evaluated according to European standard of evaluating antiseptics (EN 1040:2005 CSN EN). First we prepared a 0.5 Mc Farland (108 CFU/ml) suspension of MRSA, and exposed to three disinfectants for 15, 30, 60 and 90 seconds. Then, they were transferred to separate plates of Mueller-Hinton medium and incubated in 37^◦C for 24 hours. The plates were compared then with control plate to evaluate the efficacy of materials on bacteria by calculating the CFU/ml of plates.
Results: Three hand-disinfectants evaluated in this study had the maximum anticabterial effect on MRSA in the minimum time of exposure (15 seconds), and we found no trace of growth in any plates.
Conclusion: The three hand-disinfectans (MicroZed HD, Aseptoman and Decosept) in the concentration suggested by their companies, showed no difference in efficacy to remove MRSA from hands.

Background and Aims: One of the important fields of dentistry is surgery for dental implants. In this field, dentistry has developed considerably in recent years amongst other fields of medicine from the perspective of digital device and software application. Surgical guides help dental surgeon for more precise, confident, easier and shorter surgery. Process of producing these tools are full digital and to somehow complex due to the application of many technical devices, software and protocols. To achieve efficiency, all participants in the workflow must be aware of all steps and data requirements for production of guides. This paper investigates the production process of surgical guide comprehensively, and also, encompass all the steps in process with details.
Materials and Methods: This review article was based on searching Google scholar and PupMed databases considering key words: Surgical Guide, Guided surgery, digital dentistry, dental CAD/CAM, Additive manufacturing. More than 90% of the references were in English language and published after year 2010.
Conclusion: Today dentistry uses many digital solutions for dairy workflow and most of these solutions are developed by engineers in various fields of knowledge. Thus, this information is essential for dentists, surgeon, clinician and laboratory technician, etc. for better collaboration and participation. Amongst, advances in surgery of dental implant have been highly significant and patients benefit from better treatment and less inconvenience. In addition, dentists do surgery more precise and easier because of considering all conditions before of surgery. Thus, it is substantial inform of all steps of production process.

Background and Aims: Accurate diagnosis of vertical root fracture (VRF) is a fundamental importance in endodontics. Because of poor prognosis of VRF, digital radiographs with two horizontal angles have limitations in VRF detection. Also, Gutta-percha can produce artifacts that impair CBCT scan accuracy. The aim of this study was to compare accuracy of CBCT and digital radiography system in vertical root fracture in endodentically treated teeth.
Materials and Methods: In this study, 60 endodentically treated single teeth were selected and randomly coded. The teeth were divided into two groups: 30 with induced root fracture and 30 with no fracture. CBCT scan and digital radiographs with two horizontal angles with a difference of fifteen degrees for all teeth were performed. Two observers assessed the CBCT images and digital radiographies for presence of VRF. The statistical analysis used in this study was Weighted Kappa.
Results: CBCT had the highest sensivity (75.8) and specificity (90). Digital radiography with 68.3 sensitivity and 79.1 specificity were not as efficient as CBCT (P<0.05).
Conclusion: According to this study, the accuracy of CBCT seems to be higher than that of digital radiography in detecting VRF and provides the most reliable data in comparison of digital radiography.

Management of internal root resorption is a challenge to the endodontists. If it is left untreated, it may lead to the destruction of the surrounding dental hard tissues. Despite, routine obturation techniques are often employed without considering the best technique to solve this problem. This study presented a case of internal root resorption and apical periodontitis affecting tooth 12 (FDI) in a 31-year-old female patient, with a history of crown preparation in that region. We managed it with EndosealMTA and gutta-percha. After 12 months follow up, the tooth was still symptomless and in function and healing of bone resorption occurred.