Journal of Dental Medicine

Background and Aims: The aim of this study was to assess the outcome of short implants (<8 mm length) as an alternative to sinus lift surgery and placement of standard-length implants (10-12 mm length) for rehabilitation of atrophic posterior maxilla.
Materials and Methods: In this prospective clinical trial, 26 patients with 6-7 mm of residual alveolar bone height in their atrophic posterior maxilla were randomly divided into two groups (n=13). The test group received short implants without sinus lift surgery while the control group received standard-length implants after maxillary sinus floor augmentation. The bone loss was evaluated at 1 to 2 years after loading of implants on radiographies and the comparison between the two groups was done using chi-square test.
Results: At 1 year, two patients (15.4%) in the short implant and one patient (7.7%) in the standard implant group experienced bone loss (P=0.5). At 2 years, four patients (30.8%) in the short implant and two patients (15.4%) in the standard implant group showed bone loss (P=0.4).
Conclusion: At 2 years after loading, the bone loss was not significantly different around short and standard-length implants. Short implants appeared to be a suitable alternative to sinus lift surgery and placement of standard-length implants for rehabilitation of atrophic posterior maxilla. However, further studies with longer follow ups are still required to cast a final judgment in this respect.

Background and Aims: Passive fitness of implant frameworks are important factors for long-term success of dental implant restorations. The aim of this in vitro study was to evaluate the dimensional changes of implant supported zirconia frameworks fabricated by Zirkonzahn CAD/CAM system during fabrication stages.
Materials and Methods: The master model of 3-unit FDP was made of two implant abutments. The master model was scanned 12 times and data were saved as STL files (scanning groups). Using semi-sintered zirconia,
12 real-size frameworks (milling groups) and 12 enlarged frameworks which were then sintered (sintering group) were made in this system. Dimensions of master model and specimens of each stage were measured. The dimensional changes in respect to master model were calculated. Data were analyzed using Repeated measures ANOVA, independent t-test, and paired sample t-test at α=0.05 of significance.
Results: The milling stage showed greater dimensional changes comparing to the other stages (P<0.05). At all stages, the dimensional changes of premolar abutment height were greater than canine (P<0.001).
Conclusion: Within the limitations of this study, the results suggested that the fabrication stages and size of abutments had significant effects on the dimensional changes of zirconia frameworks.

Background and Aims: Today, resin composites are one of the most commonly used materials in restorative dentistry. However, failure in resin treatments is also common due to its chemical nature and its high talent for decay recurrence. According to conservative approaches, "conservative" treatments are more likely to be considered than "Replacement" of damaged remedies. The purpose of this study was to compare different surface preparation methods on composite surfaces to achieve the highest bond strength between the old and new composites after accelerated aging.
Materials and Methods: First, composite cylinders with a diameter of 6 and a height of 5 mm were prepared using an incremental technique and a microhybrid resin composite. The specimens were stored in distilled water for 6 months at 37°C and then the surfaces of all aged compsites were roughened using diamond milling followed by phosphoric acid etching. The specimens were randomly subjected into five groups. Group 1: GC Composite Primer. Group 2: Universal bonding containing silane (Kuraray). Group 3: Self etching adhesive (SE bond; Kuraray) Group 4: silane (Ivoclar Vivadent) + Second bottle of SE bond bonding system (Kuraray). Group 5: control group with no treatment. Then, 5 mm incremental of new composite (similar to the aged composite with different color) were placed on the surfaces of specimens, sectioned, and thermocycled for 3000 cycles for the microtensile bond strength evaluation. The specimens were evaluated using a stereomicroscope after failure. Data were analyzed by one-way ANOVA and Post Hoc Tukey test.
Results: The specimens in which silane and SE bond were used showed the highest mean microtensile bond strength and those treated by universal bond showed the least bond strength which were significantly different (P=0.02). All samples had cohesive failure patterns in all groups and the percentage of failures in old and new composites did not differ significantly (P=0.69).
Conclusion: : Based on the results, all surface preparations used in this study could provide an appropriate bond strength for repair of old composite restorations. Also, the microtensile bond strength between the old and new composites was higher than the cohesive strength of resin composite itself. However, the mean microtensile bond strength value for the group treated by universal bond was significantly lower than those treated by silane and hydrophobic containing bonding system.

Background and Aims: Despite patient’s demand increased for tooth color restorations, the stable bond between dentin and composite is a challenge in dentistry. Dentin protease activation is responsible for dentin-resin bond failure. The aim of this study was to determine the best pretreatment agent to inhibit matrix metalloproteinase and increase resin-dentin bond durability.
Materials and Methods: After collecting 24 intact third molars, the dentin surfaces were exposed immediately under DEJ. After acid etching of dentin rewetting was done with CHX 2%, EDC 0.3 M for 60 and water (control group). Then the adhesive (Single bond, 3M ESPE, USA) and composite (Filtek Z250 XT, 3M ESPE, USA) were applied. 48 sectioned dentinal specimens were prepared. The specimens were divided into 3 groups. Each group was divided into 2 sub groups (n=8). In half of each group, the micro tensile bond strength test was done immediately and another part half 6 months. Then, the specimens were evaluated by stereomicroscope and SEM. Statistical analysis was performed using SPSS23 software, two-way ANOVA and multiple Tukey and T-test comparisons. P<0.05 was considered as a significant level.
Results: There were not significant differences between immediate micro tensile bond strength of CHX, EDC and control groups (P=0.97). However, there was significant differences between CHX, EDC compared with the control group (P≤0.0001). Comparison between the immediate and 6-month bond strengths in each group, only in EDC group, there was no significant after 6 months’ difference (P=0.64).
Conclusion: EDC and CHX t did not have any effect on the immediate microtensile bond strength. After 6 months, EDC prevented bond strength deterioration, but the bond strength was decreased after CHX usage.

Background and Aims: Removable partial denture (RPDs) is a common therapy for rehabilitation of partialy edentulous patients while RPD causes a lot of periodontal problems. The purpose of this study was to investigate the effect of RPDs made in Babol dental school on the periodontal health of abutment and non-abutment teeth.
Materials and Methods: In this cross sectional study, 70 patients who were candidates for RPDs divided into four groups according to Kennedy classification. The following periodontal parameters were evaluated for abutment and non-abutment teeth, plaque index (PI), calculus index (CI), width of keratinized gingiva, bleeding on probing (BOP), periodontal pocket depth (PPD), tooth mobility (TM) and gingival recession. This clinical measurement was taken immediately before insertion of the RPD, then one, three, and six months later. These parameters were then analyzed using Mann-Whitney, Independent sample t-test, Covariance, Chi-square statistical tests.
Results: In Class I; the mean score for the width of keratnized gingiva (P<0.001), PPD (P=0.002), and BOP (P<0.001) of the abutment and non-abutment teeth were significantly different after 1 month. After 3 months there were significant differences with regard to the PI (P=0.01), width of keratnized gingiva (P<0.001), BOP (P<0.001) and PPD (P<0.001). After 6 months, only the PI, CI, and TM parameters were not statistically significant. In Class II; the mean score for width of keratnized gingiva (P<0.001) and PI (P=0.002) after 1 month, width of keratnized gingiva (P<0.001), BOP (P=0.02), PPD (P=0.05) and TM (P=0.03) after 3 months and width of keratnized gingiva (P<0.001), PI (P=0.04), BOP (P<0.001) and TM (P=0.03) after six months were statistically significant. In Class III; only gingival recession did not show any significant difference at 1 and 3 months later. The width of keratnized gingiva (P<0.001), PI (P=0.001), BOP (P<0.001) and TM (P=0.03) after 6 months were statistically significant.
Conclusion: This study showed that RPDs affect the periodontal condition of both abutment and non-abutment teeth, which can be reduced by more precise design of the prosthesis, periodontal follow ups and good oral hygiene.

Background and Aims: The emergence of social web and impact on the communication of the individuals and the scientific activities of various communities has created serious research links among researchers. This issue that how Iranian researchers keep up to date themselves with new technologies and use them to engage in scientific issues has been a challenge that is constantly being addressed in the digital world. Therefore, the purpose of this study was to evaluate the scientific production of dentistry in Tehran University of Medical Sciences in the networks of ResearchGate and Mendeley using the Scopus citation database between 2015 and 2016.
Materials and Methods: The study population included all scientific articles in the field of dentistry of Tehran University of Medical Sciences which were indexed in Scopus database between 2013-2016. The results were presented using descriptive statistics in the form of charts and tables.
Results: In this study, it was determined that the scientific outputs of the researchers from Tehran University of Medical Sciences increased in 2015 and 2016. It was also found that the coverage of articles in the field of dentistry published by researchers at Tehran Medical Sciences Universities in the Scopus citation database in the mentioned years, were in a good position in both the Mendeley and ResearchGate networks. In addition, the number of references to the articles by researchers at Tehran University of Medical Sciences on the ResearchGate network in the field of dentistry was more than the Mendeley network.
Conclusion: Based on the results of this study, it can be concluded that the performance of the researchers of the Tehran University of Medical Sciences in the field of oral and dental care and the extent of their coverage in the social networks of ResearchGate and Mendeley was high and desirable.

Background and Aims: Use of computer and internet in our modern and digitalized society is an efficient tool to be up to date and fulfil the information gaps. The aim of this study was to evaluate the extent of computer and internet usage among dental students of Islamic Azad University, Tehran, in 2016.
Materials and Methods: This descriptive study for evaluating access and usage of computer and internet by dental students was done using a researcher-made questionnaire on 401 dental students. Validity and reliability (Kappa: 0.82) of the questionnaire was confirmed. Statistical analysis was done by SPSS22 using descriptive and Logistic regression analyses.
Results: More than 95% of the students had access to the computer and Internet. 45.6% of students reported their skills were in the basic level. The major use of computer among the students was internet but only 13.2% of students used Microsoft Office program. The students used the internet for dental subjects even monthly (34.9%) or weekly (29.4%). Only 9.7% of the students had participated in educational workshop for learning methods of research. The most limitation was internet velocity. Positive correlation was found among prospering ownership status (P<0.001), economic status (P=0.05), level of education semester (P=0.038) and the computer & internet usage (what’s more in terms of access and also in terms of improve information and knowledge).
Conclusion: Based on the results, a higher economic level, higher level of education, and property ownership made better access to the computer and Internet. However, computer skills should be more concerned in educational program.

Background and Aims: Gypsum products are used for several different purposes. Adaptation and success of casting restorations are dependent on dimensional accuracy, strength, and reproduction of details of dental gypsums. This study was designed to evaluate the dimensional changes and accurate details reproduction of three type IV dental gypsums.
Materials and Methods: 60 samples in 3 groups of dental gypsums of G30,Yeti Rock and FujirockEP were evaluated. The detail reproduction of 50 micron scratched line was analyzed by a microscope at 12× magnification. The samples were assayed for dimensional changes at 2 and 24 hours and 1 week after pouring. Photograph images were taken from samples in fixed distance by a camera (Canon D600) and analyzed in corel draw software. Data were analyzed using ANOVA and chi-square (P<0.05).
Results: There were significant differences in the details reproduction between three gypsums (P≤0.05) and the highest values was for Fujirock EP, Yeti Rock. The G30 did not reconstruct the details. There was no significant difference in the dimensional changes of the evaluated gypsums based on time (P≥0.05).
Conclusion: All three different gypsums evaluated in this study showed the dimensional stability during one week. Fujirock EP and Yeti Rock could reconstruct the details and G30 gypsum could not.

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.

Background and Aims: Most children get a lot of anxiety while they visit a dentist. The most important factor in the child's fear at the beginning of treatment is the syringe and needle. Ways to cope with this anxiety include behavioural control techniques such as mental regeneration, distraction, and induction. The purpose of this study was to compare the pain and anxiety in children when using a syringe and toy- shape syringe needle. This study was the first study that used a toy-shape needle cover.
Materials and Methods: This clinical trial study was conducted on 20 children age from 5 to 8 years. More than half of them were anxious with Cfss-Ds (Dental Subscale of the Children's Fear Survey Schedule) and FIS
(Facial Image Scale) anxiety diagnostic tests, and the rest of them were not anxious. Patients were randomly divided into two groups. The first group received local anesthesia with conventional syringe and the second group, by syringe with toy shape needle cover. Following, the first group received local anesthesia by syringe with toy shape needle cover, and the second group, by a conventional syringe. Heart rate measuring and pain evaluating test was performed. Analysis of heart rate and anxiety data was performed by non-parametric wilcoxonsianed Ranks T-test (P-value was considered significant at 0.001).
Results: The mean amount of pain measured after using a syringe with a toy shape needle cover and using conventional syringe had a significant difference of 5.20% between the two groups. The pain was reduced in children who received local anesthesia by syringe with toy shape needle cover (P<0.001).
Conclusion: The physical appearance of the injection device plays an important role in reducing the anxiety and pain of injection in the children.

Background and Aims: Management of an emergency is ultimately the dentist’s responsibility. Therefore, the dentists need to be able to manage an emergency and perform Cardiopulmonary Resuscitation (CPR) if necessary. The present study was undertaken to assess the knowledge of final-year dental students in Tehran regarding CPR.
Materials and Methods: In a cross-sectional study, 200 final-year dental students (44 males and 156 females) from 4 dental schools in Tehran were randomly selected and surveyed using a multiple choice questionnaire evaluating their knowledge about CPR. The data were analyzed by SPSS16 software using two descriptive and inferential statistical methods via chart drawing of statistical quantities calculation and analysis of variance.
Results: The mean score was 5.43±2.43. A positive correlation was found between receiving practical training and level of knowledge (P=0.001). However, the results showed no statistical differences between sex (P=0.409) or various dental schools (P=0.089).
Conclusion: Since, the level of knowledge about CPR among participants were poor, there is a perceived need for further training in dental schools.

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.

Background and Aims: Xerostomia is a clinical condition that can affect the quality and quantity of saliva. Saliva is considered an important factor in retention of edentulous patient’s denture wearers. Thus, increasing the prevalence of xerostomia in modern societies is considered a limiting factor in the quality of denture retention. This article reviews the most common techniques of denture manufacturing in edentulous patients with xerostomia and investigates the advantages versus disadvantages of each.
Materials and Methods: In this review, PubMed and google scholar search engines were searched for the following keywords: Flexible Denture, Artificial Saliva Reservoir, Hyposalivation, Hypofunction, and Xerostomia. We evaluated the flexible dentures and dentures with artificial saliva reservoirs in both jaws along with their advantages and disadvantages. 10 articles, specifically discussing complete denture fabrication in patients were selected.
Conclusion: Follow-up results showed that the flexible dentures and split dentures with saliva reservoirs to be effective in improving the quality of life of these patients and therefore can be a considered as a successful treatment option in the prosthetic rehabilitation of these patients.

Background and Aims: Regarding the high prevalence of caries and oral dental diseases, especially in the elderly, and the increasing attention of people to using the concept of quality of life, this study was conducted to determine the relation between oral and dental health and the quality of life in elderly people in Yazd.
Materials and Methods: This cross-sectional study was performed using data from the Yazd Public Health Survey (YAHS) with a sample of 9293 people, in 1393-94. All information was collected from 1907 elderly people aged between 60 to 70 years, including quality of life and oral and dental indexes from the comprehensive questionnaire of YAHS. Data were analyzed by independent t-test and Spearman correlation coefficient using SPSS16 software.
Results: There was a significant relationship between the quality of life and oral hygiene (P<0.01). Also, the score of quality of life and oral health was significantly related to education (P<0.01).
Conclusion: This study showed the positive relation between the oral health the quality of life. In addition, there was a quality of life level in the elderly people with poor oral hygiene.

Background and aims: Solubility is an important property of luting cements in determining clinical durability. The aim of this study was to compare the solubility of Panavia, Calibra and Maxcem resin cements with that of GC Fuji PLUS resin modified glass ionomer cement in three different pH values.
Materials and Methods: A total of 96 specimens were prepared (8mm diameter, 4mm thickness) according to manufacturer instructions. After setting, they were desiccated and weighed. The specimens were kept immersed in distilled water and lactic acid solution (pH values of 3 and 5) for 30 days and then removed and weighed again. Data were statistically analyzed by SPSS18 using two-way ANOVA with P≤0.05 set as the level of significance.
Results: The results of this study showed no significant difference between three pH values (P=0.08). The Calibra resin cement had the lowest value of solubility in distilled water and both pH of lactic acid. GC Fuji PLUS resin modified glass ionomer cement had the highest value of solubility in lactic acid and the Maxcem resin cement had the highest value of solubility in water.
Conclusion: The solubility characteristics of resin modified glass ionomer and three different resin cements were significantly affected by their composition and the storage condition.

Background and Aims: One of the most important determinants of health is Oral Health Literacy (OHL). The aim of this study was to investigate the OHL among nomadic population in Kouhrang city as pristine society.
Materials and Methods: This was a  cross -sectional descriptive study among 200 nomadic population aged 18-60 years of Kouhrang city in 2018. Data were collected using a questionnaire and face-to-face interview, sampling method was performed by randomized cluster. The questionnaire consisted of 17 questions in 4 sections of reading comprehension, listening, perception of number, and decision making. According to the number of questions, the questionnaire score was formed 0 to 17 and the nomadic populations were categorized into three groups with inadequate OHL (0-9), borderline OHL (10-11), and adequate OHL (912-17).
Results: The mean and standard deviation of the participants in this study was 35.49±12.00. The results showed that 7.00% of participants had sufficient OHL (12-17), 21.51% borderline (10-11), and 71.50% had inadequate OHL
(0-9). The mean and standard deviation of OHL score in general was 7.65±2.80, and the mean DMFT index was 8.03±5.64 (P<0.001).
Conclusion: The results of this study showed that the OHL score in the nomadic population was low, and also the mean DMFT index was very high. It is necessary to pay attention to the timely prevention and treatment of the teeth, as well as serious attention to the health education in this population.

Background and Aims: Dental diagnosis may be affected by the occurrence of the errors in the intra-oral radiographic images and the patients’ treatment plan can be problematic in these cases. The repetition of these radiographs increases the risks of radiation exposure for the patients in turn. The present study assessed the incidences of common periapical radiographic errors taken by dental students in oral and maxillofacial radiology department of Mashhad dental school in 2017.
Materials and Methods: In this cross-sectional descriptive study, 1470 periapical radiographs prepared by student during a semester of 2017 were collected and evaluated. Radiographic observations were done and the incidence of conventional radiographic errors were determined. Finally, the frequency and percentage of radiographic errors were determined based on the type of radiography sex, the age of the patient, and the history of radiography. Then, results were analyzed using the Chi-Square test and SPSS19 (P=0.05).
Results: Film placement (27.2%), cone-cut (27.2%), elongation (13.2%) and horizontal angle (10.9%) were reported as the most common radiographic errors. The repetition rate of the radiographs was 2.9%; among them, the highest errors were Cone-cut errors in the upper jaw
Conclusion: Based on the results of this study, the most radiographic errors included film position and Cone-cut errors and these two errors were the most frequent cause of repetitive radiographies that required the provision of specific training for the prevention of these errors.

Background and Aims: Reconstruction of osseous defects is one of the ideal goals of periodontal treatments and dental implant therapy. Different biomaterials have been used for this purpose and many studies have tried to compare and introduce the best ones. The present study aimed to evaluate the effect of PDFDB (Partially Demineralized Freeze-Dried Bone Graft) and FDBA (Freeze Dried Bone Allograft) on the regeneration of rabbit calvarial defects.
Materials and Methods: In this experimental study, 48 similar defects with the diameter of 8 mm were generated in the calvarium of 16 rabbits. Two defects were filled with FDBA and PDFDB, while the other one remained unfilled as the control group. All defects were covered by collagen membranes. 6 and 12 weeks after surgery, the histologic and histomorphometric tests were performed to evaluate the following variables: the rate of new bone formation and its type, the amount of residual grafting material, degree of inflammation and pattern of bone formation. Comparison of osteogenesis percentage and residual biomaterial was performed by repetitive variance analysis, whereas qualitative variables were compared by Friedman non-parametric test.
Results: Regarding bone formation percentage, there was no statistically significant difference between three different groups at 6-week (P=0.33) and also at 12-week time points (P=0.98). The amount of residual material in the PDFDB group was significantly lower than FDBA (P=0.04) in the 6-week samples. However, this difference was not significant in the 12-week samples (P=0.41). Bone quality showed statistically significant difference between graft containing groups and control group after 12 weeks (P=0.01). It means, all samples in FDBA and PDFDB groups displayed lamellar bone after 12 weeks while in control group, only woven bone or a combination of woven and lamellar bone was seen.
Conclusion: FDBA and PDFDB demonstrated similar regenerating effect in the rabbit calvarial bone defects and hastened bone maturation compared to the non-grafted defects.

Background and Aims: Various methods to induce anesthesia have been investigated in situations where the primary inferior alveolar nerve block (IANB) injections fail. The aim of this study was to compare the effect of synergic effects of anesthetic injection of prilocaine supplemental with that of lidocaine anesthesia in teeth with irreversible pulpitis.
Materials and Methods: This study was a parallel-controlled clinical trial on 58 patients with one mandibular molar tooth having irreversible pulpitis. The first anesthesia was injected with an inferior alveolar block with 2% lidocaine anesthesia. Patients who failed pulpal anesthesia were randomly divided into two groups; case and control groups. In the case group, IANB was injected with 3% prilocaine, and in the control group with 2% lidocaine anesthesia. Anesthesia after the second injection was evaluated by three methods of numerical evaluation of the patient's response to Electric Pulp Tester (EPT), the severity of the patient's response to the cold test, and the extent of pain during the onset of access cavity latency on the Visual Analog Scale (VAS). Statistical analysis was performed using T-test and Mann-Whitney tests.
Results: There was no significant difference between the two groups in terms of depth of anesthesia (P>0.05).
Conclusion: The results of this study showed that there was no difference between 2% lidocaine and 3% prilocaine in the depth of supplemental IANB anesthesia after failure of first IANB in mandibular molar teeth with irreversible pulpitis.
 

Background and Aims: Oral squamous cell carcinoma (OSCC) is one of the most prevalent oral cancers with increased risk in individuals younger than 40 years especially in developed countries. There are many evidences that people who have plenty of fruits and vegetables in their diets tend to have lower risk of cancer. In this study, we evaluated the anticancer effect of four medicinal plants of Otostegia Persica, Otostegia Michauxii, Otostegia Aucheri, and Hibiscus Sabdariffa on OSCC cell lines.
Materials and Methods: In this study, methanolic & dichloromethane extracts of the above medicinal plants were used in order to evaluate their effect on oral squamous cell carcinoma cell line in different concentrations and after 24 , 48 and 72 hrs by MTT assay test. Finally, the appropriate concentration for repeating the test were chosen.
Results: In this study, the mean amounts of IC50 for O. persica and O. Aucheri were less than the two other herbs and the least and most amount of IC50 were related to the dicloromethanolic extract of O. persica after 72 hrs and the water extract of H. sabdariffa after 24 hrs, respectively.
Conclusion: It was concluded that all of the plants evaluated especially O.Persica and O.Aucheri had anticancer properties and dichloromethalonic extracts of these plant were more effective than that of methanolic extract.