Journal of Dental Medicine

Background and Aims: The precision of periodontal pocket measurements with periodontal probe is related to different factors. Some of these are related to examiner. The purpose of this study was to compare the right-handed and left-handed dental students in the measurement of periodontal pocket depth (PPD).
Materials and Methods: Eight systemically healthy adult patients (mean age of 35 years) with 0.5-6 mm periodontal pocket depth and a minimum of 20 teeth were examined by 4 right-handed and 4 left-handed students of dentistry (mean age of 25 years). These students were trained for periodontal examination probe depth measurements with Williams probe. Measurements were inserted in SPSS software and analyzed with Iintraclass correlation coefficient (ICCS) and T-test.
Results: There was statistically significant difference in the measurement of PPD between right-handed and left-handed examiners in the whole mouth (P<0.05), but this difference (0.08 mm) was not clinically significant. The most difference was found in the posterior teeth of mandible at right quadrant (mean=0.2 mm). Analyses of each pair of same handed and different handed examiners with T-test and ICCS showed that these measurements were nearly similar and reproducible.
Conclusion: There was no clinically significant difference in measurement of PPD between right-handed and left-handed examiners.

Background and Aims: Because of high prevalence of TMJ dysfunctions , increased promotion of diagnostic and treatment methods is necessary. In many cases, in addition to disc position, morphology of other joint components such as articular eminence can be changed and therefore the probable correlation between disc position and morphology of hard tissue components can be used for prediction of internal derangements. The aim of this study was to evaluate the correlation between the position of disc and morphology of articular eminence of TMD`s patients using magnetic resonance imaging (MRI).

 Materials and Methods: In this cross sectional study by evaluation of digital MRI files, ultimately 78 joint images were identified which had sufficient quality and resolution for review. Then the MRI images, were observed and evaluated by 3 oral and maxillofacial radiologists to determine the disc position (normal, anterior displacement with and without reduction, and posterior displacement) and morphology of articular eminence (Box, Sigmoid, Flattened). Ultimately the results that were reported at least by 2 observers were included as the final results and were recorded in the check list. Data were analyzed using Chi-Square test and Fisher test.

 Results: In this study, no case of posterior disc displacement was found and therefore was excluded from the study. Articular eminence morphology (Flattened versus Sigmoid) showed statistically significant correlation with anterior disc displacement with and without reduction (P-values for anterior displacement with and without reduction were 0.03 and 0.002, respectively). No significant difference was found between the sigmoid and box types in relationship with disc displacement (P-values for anterior displacement with and without reduction were 0.72 and 0.70. In this study, no significant difference between the anterior disc displacement with reduction and anterior disc displacement without reduction in relationship with the morphological changes of articular eminence in any of the cases were found.

 Conclusion: The results showed that flattening of articular eminence had significant relationship with anterior disc displacement.

  The aim of this review article was to define the mechanism of action and effects of commonly used medications on the tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and medline (1980-2013). 63 articles were included in this review. 34 of them were related to the effects of hormones and analgesics, were evaluated in this article but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Non Steroidal Anti-Inflammatory Drugs (NSAIDs) reduced the rate of tooth movement while non-NSAIDs such as acetaminophen had no effect on the rate of OTM. Corticosteroids, parathyroid hormone and thyroxin increased the rate of tooth movement. Sturgeons might slow OTM, but experimental studies are lacking. Medications might have an important influence on the rate of tooth movement and information on their consumption is necessary to adequately discuss treatment planning with patients.

  Background and Aims: Adequate retention has significant importance in the prognosis of implant supported cemented the restorations. Limited literature had evaluated the effect of direct wax up or use of plastic coping on the retention of these restorations. This aims of this study was to compare the retention of castings fabricated by the plastic coping and direct wax up for single crown and bridge in three implant systems.

  Materials and Methods: 28 specimens of each implant systems were randomly divided into 4 groups. Groups included wax patterns for single crowns and bridges that were made from plastic coping or direct wax up. All the wax patterns were invested and casted with base metal alloy, in similar conditions. After castings were cemented to the related abutments, the specimens were subjected to a pull out force in a universal testing machine at a cross head speed of 0.5 mm/min. The load required to decement each casting was recorded and the mean values for each group were calculated. Data were analyzed using three-way ANOVA.

  Results: Comparing the between systems in crowns fabricated from plastic coping, there was no significant difference between Replace and Implantium (P=0.124), but ITI had significantly lower values than that of other systems (P<0.001 Comparing the systems in crowns fabricated from direct wax up, Implantium had the greatest retention and ITI had the lowest retention (P<0/001). Comparing the bridges with both method, Replace had the greatest retention and ITI had the lowest retention.

  Conclusion: Implantium and Replace system exhibited the highest retention for fabricating crowns, and bridges, respectively.

  Molecules produced in various diseased tissues or drugs and nutrients consumed regularly by patients, can reach the mechanically stressed paradental tissues through the circulation and interact with local target cells. The combined effect of mechanical forces and one or more of these agents may be inhibitory, additive or synergistic. The aim of this review was to outline the mechanisms of action and effects of some commonly used drugs on tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and Medline (1980-2013). 63 articles were included in the review. 34 of them related to the effects of hormones and analgesics were evaluated in the first part of this review. The rest of them (29 articles) were evaluated in the current review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Vitamin D₃ might enhance the pace of tooth movement, but dietary calcium and fluorides appear to reduce the rate of OTM. Bisphosphonates (BPNs) are considered to have marked inhibitory effects on the rate of tooth movement. Nicotine and nitric oxide might effectively increase the speed of OTM. All drugs reviewed had therapeutic effects, as well as side effects, that may influence the cells targeted by orthodontic forces. Therefore, it is imperative that the orthodontist pays close attention to the drug consumption history of each and every patient, before and during the course of orthodontic treatment. When the use of drugs is revealed, their effects and side effects on tissue systems should be explored to determine their potential influence on the outcome of mechanotherapy.