مجله تحقیق در علوم دندانپزشکی
سال دوازدهم شماره 4 (پیاپی 46، زمستان 1394)

Probiotics could have benefits on oral health, partially through modifying oral cavity microflora. The purpose of this study was to investigate the effect of a commercial probiotic yogurt consumption on oral halitosis. This clinical trial was conducted on 44 volunteers suffering from halitosis with oral cavity origin. The subjects were given 200 ml probiotic yogurt daily for a period of two weeks. One examiner evaluated subjects’ mouth odor at baseline and after two weeks using organoleptic assessment (5 point scale: 0= no, 1= brief, 2= medium, 3=severe, and 4= very severe) at 10 and 50 cm distances. Data were analyzed by SPSS software using Wilcoxon test (&alpha=0.05). Baseline mean organoleptic scores (10 and 50 cm) were 2.63±1.12 and 1.95±1.23, which decreased to 1.45±1.10 and 0.95±0.93 at the end of study (P< 0.001). consumption of probiotic products could be considered as an effective strategy for improvement of halitosis with mouth origin.

Back ground and Alveolar ridge resorption following tooth extraction could be minimized via socket preservation techniques by using grafting materials. The aim of this study was to compare the effect of Demineralized Bone Matrix and Absorbable Gelatin Sponge on preservation of the extraction socket bone level. This double blind clinical trial study was accomplished on 20 cases (10 patients). The patients with the indication of two similar teeth extraction in a jaw who declared their written and conscious agreement for the research were included in this study. First, after similar teeth extraction in a jaw, Demineralized Bone Matrix material was embedded randomly into one extraction socket and Absorbable Gelatin Sponge on the other one. Then, the height of alveolar socket was measured by means of taking parallel periapical radiography and making a guiding stent. Four mounts later, another parallel periapical radiography was taken in the same manner as the previous one by using the fabricated guiding stent as guidance. Then the height of alveolar socket was measured. Differences inside and between the groups were analyzed statistically by using the “paired t-test” and “t-test” analyses respectively. In both groups, reduction on the amount of alveolar ridge height observed. Bone level reduction in the Absorbable Gelatin Sponge and Demineralized Bone Matrix group was 3.03 ± 2.07 mm and 0.76 ± 0.47 mm, respectively, with statistically significant difference between them (P < 0.01). Bone level changes in Absorbable Gelatin Sponge group was 3 times more than Demineralized Bone Matrix group, which means that Demineralized Bone Matrix is more capable of preserving the bone height of the extraction socket than the Absorbable Gelatin Sponge.

Smear layer acts as a physical barrier that hinders full effectiveness of Ca(OH) 2 via interacting with the transfusion of hydroxyle and calcium ions through dentinal tubules. The purpose of this study was to measure the pH changes of the external root surface of human teeth due to hydroxyle ion diffusion using different chelating agents.Method and Materials: In this in vitro study, 96 anterior maxillary teeth were prepared to a master apical size of #40 4%. Samples were randomly divided into 4 experimental groups of 12, group1: EDTA17% + NaOCl 1.3% group2: Citric acid 20% + NaOCl 1.3% group3: Noni + EDTA17% group4: NaOCl 1.3% + MTAD and 4 control groups. After removing the smear layer, Ca(OH)2 was placed in experimental samples. Root canal surface pH was measured for 30 days. Data were analyzed using t-test, one way ANOVA and Tuckey multiple comparisons. Noni+ EDTA showed the highest average of PH among experimental (pH=8.02) and control (pH=7.61) groups (p&le0.036), followed by MTAD+ NaOCl, EDTA+ NaOCl & Citric acid+ NaOCl, respectively. (pH=7.73, 7.64, 7.65) It was concluded that Noni +EDTA17% promoted greater hydoxyle ion transfusion and subsequent alkalization in the outer surface of the root due to better omission of smear layer.

Considering the importance of detecting the secondary proximal caries and known effects of false positive and false negative diagnosis and regarding the lack of information about this issue, the purpose of this study was to compare the ability of CCD and PSP sensor in detection of secondary proximal caries in permanent premolar teeth with the gold standard method. In this diagnostic study, 40 normal extracted premolar teeth were used. Class ǁ cavities were prepared and filled with amalgam and digital radiographs were taken. Then, the secondary caries were made artificially by acid solution and digital images were obtained with the above condition. Evaluation of all radiographs was performed by 5 observers. Detections were performed and results were analyzed with statistical tests. The unacceptable detection for CCD was 30% and for PSP was 37.5%. This difference was not statistically significant (p<0.4). There is no superior for the clinical use of CCD and PSP receptors in detection of proximal caries in permanent premolars

Oral lichen planus(OLP) is a chronic mucocutaneous, inflammatory disease. Although etiology of this disease is unknown, but such factors such as antioxidant deficiency and zinc are responsible in this disease. The aim of this study is evaluation and comparison of serum zinc in lichen planus patients and healthy subjects. This study was designed as case- control. In total 52 patients with OLP(36 women and 16 men) were enrolled as case group and 48 self-admitted healthy people (36 women and 12 men)were selected as control group. Measurement of zinc was carried out in plasma. T-test was used for statistical analysis with significant level set at p<0.05. The mean±SD of serum zinc in case group was6.4±1.02 and in control group was 12.1±1.5 µg/dl, respectively. There were significant difference between two groups.P<0.01 Results of this study showed that plasma levels of zinc in OLP patients were lower than those in healthy subjects.

Clinical and radiographic diagnosis of vertical root fracture is difficult. The aim of this study is to compare two different resolutions of CBCT and CMOS digital sensor for diagnosis of vertical root fracture. In this diagnostic in vitro study, 80 single rooted teeth were selected and after canal preparation were sectioned from 2 mm below the CEJ. The teeth were put in two groups 40 teeth with induced root fracture and 40 remained intact served as control samples. Teeth were put in dry mandible and 2 layers of wax was used as soft tissue. All samples were imaged by CBCT with two resolutions and CMOS sensor with 0,and ±15 degrees. Positive predictive value(PPV) and negative predictive values(NPV) of the techniques were calculated with Ratio test. The reliability in diagnosis of fracture in CBCT was 100% and the reliability in researcher in radiography was 75%. No significant difference was found between the two resolutions of CBCT, but there was a significant difference between CBCT and CMOS digital sensor(P<0.07). CBCT had higher ability in VRF detection comparing to digital radiography with CMOS sensor, while both resolutions of CBCT have same abilities

Faculty members are pillars of educational system. Their empowerment will positively affect their performance leading to higher levels of motivation and problem solving. The aim of this study was to determine the views of faculty members on effective strategies of empowerment and related factors in the Dental Branch of Islamic Azad University in 2014. A descriptive study on 115 students of dental branch of Tehran Islamic Azad University in 2014 was designed using a standard 5-scale Likert questionnaire and the parameters were academic status, work experience, academic interest in the job, employment status and type of service. The questionnaire was consisted of 28 options in nine fields. Seven options with respect to incentives, 4 options in relation to facilitating communication specialist, 3 options with regard to participation in the learning process, 2 options in terms of specialization, 3 options regarding the environmental factors of education and vocational training and two options for job enrichment, self-control and being up to date. The chi-square test was used for data analysis. According to faculty members, the most important factor influencing their empowerment was availability of resources (education and research) with the highest point (14/4). Evaluation of faculty members by students and allocation of a strictly educational atmosphere had the lowest points of 2/84 and 2/38 respectively. It seems that improving the motivation, updating and participation of faculty members in educational decision-making processes are three main aspects of their empowerment.

Squamous cell carcinoma, is the most common malignancy of the oral cavity considering grade and stage are the most important determinants of prognosis. Mast cells play an important role in tumor development and progression through angiogenesis. The aim of this study was to investigate the association of mast cell concentration and microvascular density with the grade and stage of oral squamous cell carcinoma (OSCC). This study is descriptive as the number of mast cells(MCD) and microvascular density(MVD) were examined in 87 cases with OSCC. Mast cells and microvascular density were stained by immunohistochemistry assay, All data obtained were statistically analyzed from descriptive statistics, ANOVA and Spearman’s correlation coefficient respectively, using SPSS 16 software. The mean mast cells density around the tumor was 60/07±15/18 and within tumor 51/84 ±10/63. Average microvascular density around the tumor was 46/79±9/61 and within tumor 41/45 ± 7/62. The correlation between the mast cell and microvascular density has a correlation r = 0/77. The mast cells and microvascular density was positively related to Grade and Stage and predictive of cervical lymph node metastasis (P < 0.05). Mast cell concentration and microvascular density may be used as a factor for detecting grade of the tumor and metastasis to cervical lymphatic nodes.

Empathy between dental practitioners and dental patients increases communication between them, resulting in improvements in patient satisfaction and efficacy of oral health care. Proper communication and empathy between dental practitioners and patients are major concerns of professors, managers and education programmers. The aim of this study was to evaluate empathy levels among dentists participated the 9th Iranian General Dentists Association Congress in 2014. In this cross-sectional study, 200 dentists completed the persian version of Jefferson Scale of Empathy-Health Care Provider Version (JSE-HP). Demographic and data obtained from the questionnaires was analyzed by SPSS v.20 using Chi-square (a = 0.05). Among 200 participant, 103 were male (51.5%) and 97 were female (48.5%) and 120 dentists had positive attitude to empathy (60%) and 80 dentists had negative attitude to empathy (40%), Statistical tests showed no significant differences between age, sex, general dentists and specialists, graduates from domestic and foreign universities and time of graduation. (p value > 0.05). The empathy scores of studied dentists were less than the acceptable levels. It is necessary to design proper educational programs to improve empathy of dentists with patients