Journal of Dental Medicine
Year:2009 | Volume:21 | Issue:4 (57)|Papers Count:12

Gingival overgrowth is a drug-associated side effect occurs in pediatric patients. Phenytoin, cyclosporine, calcium channel blockers, and amphetamine are primary drugs that can cause gingival enlargement in children. Pediatric patients are more prone to drug-associated gingival overgrowth rather than adults. Gingival overgrowth may cause functional, phonetic, and nutritional difficulties, and more importantly, may affect the psycho-social development, self-esteem, and quality of life in children. However, the researches about this issue are rare. This Part I paper provides an analysis of pediatric systemic disease and corresponding prescribed medications for selected physical and mental health conditions. This paper describes the morbidity and risk for children related to gingival overgrowth and proposes a framework for action that will be more completely described in a part II paper on this topic.

Background and Aim: Angiogenesis plays a central role for development and progression of malignant tumors. It is considered as an important factor for predicting of malignant tumor's behavior such as metastasis to lymph nodes and other clinicopathologic factors. However, it is still a controversial factor especially in oral squamous cell carcinoma.The aim of this study was to evaluate the correlation between angiogenesis and clinicopathologic parameters such as presence of metastatic cervical lymph node in the tongue squamous cell carcinoma.Materials and Methods: In this cross-sectional study, 40 cases of squamous cell carcinoma of the tongue were selected from the archive of cancer institute of Tehran University of Medical Science. Sections were prepared from paraffin blocks and immunohistochemically stained with antibody against CD34. Stained vessels were counted in 4 fields ,the most vascular areas at low magnification, in each areas of intratumoral ,peritumoral and nontumoral adjacent tissue in two groups with metastatic lymphnodes (N+) and without (N-). The average counts from the four most vascular areas were recorded as the mean microvascular density (MVD). Data were analyzed by 3way ANOVA and Independent T- test with p<0.05 as the level of significance.Results: High mean MVD-CD34 was significantly correlate with positive cervical lymph node metastasis in intra tumoral and peritumoral areas but there was no significant correlation between mean MVD-CD34 and age, gender, and differentiation of tumor.Conclusion: Based on the results of this study, CD34 can help us to determine the presence of cervical lymph node metastasis and may also determine the outcome of a primary squamous cell carcinoma of the tongue.

Background and Aim: A major aspect of the adaptive host response in periodontitis is the antibodies. Several risk and susceptibility factors for periodontitis, including smoking, age and composition of the subgingival microflora, have also been suggested to influence antibody production. The present study was conducted to investigate plasma levels of immunoglobulin (Ig) G antibodies in periodontitis patients of Caucasian Iranian heritage referred to dental faculty, Tehran University of Medical Sciences in relation to disease severity and smoking.Materials and Methods: In this study, 36 patients with severe periodontitis, 39 with moderate periodontitis and 40 controls without periodontal destruction were enrolled. From the total of 80 patients, 21 were diagnosed with aggressive periodontitis and 54 with chronic periodontitis. IgG isotypes were analyzed in plasma samples.Results: Patients group in comparison with control group had shown higher level of Immuno globolins. There was no significant difference about the IgG1 level in moderate and seven group and also in chronic and aggressive groups (p<0/001). But the level of IgG2 was shown the significant difference in the all study groups. Smoking was significantly reduced the level of IgG1 and IgG2.Conclusion: The current study shows that non-smoker periodontitis patients have higher levels of IgG2 than smoker periodontitis patients.

Background and Aim: One of the most common causes of facial pain, is muscular pain. MPDS is one of the most important disorders of facial area that many of patients suffer from pain, tenderness of one or more masticatory muscles and limitation of movement. Psychological factors play an important role in MPDS. Anxiety and depression by increasing muscle tension, can cause myofacial pain syndrome; They can also accompany the syndrome as comorbidities or develop as sequelae of chronic pain and disability. Many approaches can be used to treat myofacial pain syndrome. The least invasive and least traumatic approach should be selected. Often, treatment for myofacial pain syndrome fails, because underlying problems go untreated. Progressive Muscle Relaxation (PMR) is mainly used for treating anxiety and depression. The aim of this study was to evaluate the effect of PMR in improving signs and symptoms of patients with MPDS.Materials and Methods: In this before and after clinical trial study, 33 patients with MPDS that had anxiety and or mild depression (were assessed by Beck Inventory) were treated by PMR in a period of a month (3 visits)and were followed up until 2 months. Analysis was done using paired t-test/ wilcoxon-sign-rank test.Results: The results of this study showed that variants like intensity of pain, tenderness of masticatory muscles, maximum opening of mouth with and without pain, anxiety (p<0.001) and depression (p=0.001) improved significant 16 after treatment in comparison with before treatment.Conclusion: In conclusion, PMR is effective in improving signs and symptoms in patients with MPDS. Therefore psychological status should be considered in treatment plan of these patients.

Background and Aim: One of the unique properties of MTA is its setting ability in presence of moisture. The sealing ability of MTA used as a root-end filling was shown to be unaffected by the presence of blood, in vitro. It has been recommended that, because of MTA ability to set in the presence of blood, there is no need to dry the perforation site before MTA placement. On the other hand, based on an in vitro study, it is recommended that hemorrhage be controlled at the perforation site and blood be removed from the perforation walls before placement of tooth-colored MTA. Blood contamination may also affect the crystalline structure of MTA. The microhardness of a material is influenced substantially by some fundamental properties of the material such as crystal structure stability. Thus, it can be used as an indicator of the setting process. It can also indicate the effect of various setting conditions on the overall strength of a material. The aim of this study was to evaluate the effect of blood contamination on microhardness of white and gray MTA as an indicator of their setting process.Materials and Methods: In groups 1 and 2 each material has been mixed with distilled water according to manufacturer’s instruction (No contamination groups). In groups 3 and 4 samples were prepared like groups 1 and 2 but the surface of material placed in contact with blood (Surface blood contamination groups). Samples of groups 5 and 6 were mixed with blood instead of distilled water and also the surfaces of the materials were placed in contact with blood (Mixed with blood groups). All samples were stored in 370C and 100% humidity for 96 hours. The microhardness of the samples was measured with Vickers test.Results: White MTA samples which have not contaminated with blood had the highest microharness (59.9±11.4 N/mm2) while gray MTA mixed with blood had the lowest hardness (18.45±7.8 N/mm2). One-way ANOVA test showed that contamination with blood significantly reduces the microhardness of both white and gray MTA (p<0.001). The difference between white MTA and gray MTA was significant in groups of no contamination (p<0.001), surface blood contamination (p=0.043), and mixed with blood (p<0.001) according to T-Test analysis. In all of them white MTA had higher hardness than gray MTA.Conclusion: According to results of our study we recommend that hemorrhage should be controlled and any blood contamination should be removed before placement of both white and gray MTA.

Background and Aim: Because of stable aesthetic and minimum destructive technique, Porcelain laminate veneer has an important role in aesthetic dentistry. But main reason of failure in this treatment is restoration fracture. Therefore tooth preparations have an important role in fracture resistance of porcelain laminate veneer. The aim of this in vitro study was to evaluate the fracture resistance of porcelain laminate veneer dependent on tooth preparation after exposure to dynamic loading.Materials and Methods: In this study, 30 caries free mandibular incisors were devided into 3 groups. First group (Control group) remained unprepared. In second group (Window preparation) facial surface was prepared with 0.3, 0.5, 0.7 mm in cervical, middle and incisal, respectively. In third group (Incisal lap preparation) the preparation was like second group and included 2 mm of incisal edge. 20 feldespatic ceramic veneer were bonded adhesively with dual-cure luting cement (Rely X). All specimens were subjected to cyclic mechanical loading (720000 cycles, 1.3Hz, 30N) and thermal cycling (5-55 C, dwell time 60seconds, 500 cycles). The specimens were exposed to Universal testing machine until failure occurred with a constant crosshead speed of 1mm/min.Results: Five specimens of first group, one specimen of second group and two specimens of third group fractured during cyclic loading. The mean failure loads (MPa) after exposure to continues load were as follows: First group: 168/96 (561.01-1115.08), second group: 394.10 (248.92- 641.33) and third group: 273.47 (135.45 - 479.80). Data analysis was performed by ANOVA, LSD and chi Square test.Conclusion: Significant difference between 3 groups was found. Fracture resistance of control group was significantly higher than other groups and window group preparation was significantly higher than incisal lap group. The samples were under the cyclic loads before they put under the continuous pressures of universal testing machine. It was clear that incisal lap preparation is more resistance against fatigue failure compared to window preparation.

Background and Aim: According to controversies in the prevalence of hypersensitivity to dental local anesthetic drugs and patients who claim hypersensitivity to these drugs, the aim of this study was to determine the prevalence of hypersensitivity to dental amide local anesthetic drugs in patients referred to Tehran Allergy Clinic in 2005-2007.Materials and Methods: In this Study (Review of existing data), records of 130 patients who were referred to "Tehran allergy Clinic" (2005-2007) were studied.Results: The average age of patients was 29.5±18.8 years. 34% of cases showed positive skin reactions to at least one of the tested Lidocain concentrations and 10% of cases showed positive skin reactions to at least one of the tested Prilocain concentrations. There was a statistically significant difference in hypersensitivity to Lidocain 0.01 and 0.001 (p=0.017) and also between Lidocain 0.001 and 0.0001 (p<0.01). There was no statistically significant difference between other tested drug concentrations (p>0.05).Conclusion: Many patients with history of hypersensitivity, show positive reaction to local dental anesthetic drugs. Prilocain hypersensitivity reactions are less than Lidocain. So application of Prilocain accompanies with less risk but its application should not be considered completely safe.

Background and Aim: As composite-dentin bond strength is affected by cavity preparation and the bond strength of composite resin to new and used bur prepared dentin has not yet been evaluated, this study evaluated the effects of cutting dentin with different cutting efficacy (new and used) of burs on composite-dentin shear bond strength using self-etching primer bonding system and total etching bonding system.Materials and Methods: Sixty caries free human 3rd molar were sectioned in occlosal surface to expose dentin, then polished with silicon carbide paper and randomly divided into four groups. Each group was prepared in a depth of 0.5mm of dentin, using new diamond bur, or used diamond bur. To change into a used bur, each new rough diamond bur had to work on bovine enamel for 30 minutes, under a load of 150g. Then, each group was bonded, using a total etch adhesive (single Bond) or a self etch adhesive (clearfil SE Bond) So there were 4 groups : 1-SE Bond, New bur; 2-SE Bond , used bur; 3-Single Bond , New bur ; 4-Single Bond, used bur. Similar composite capsules(Filtek Z250) were bonded to dentin surface and cured. specimens were stored in physiologic saline for 48h at 37°c , then put under shearing load to define composite - dentin shear bond strength. Results were interpreted via statistical analysis (T-test & two - way variance).Results: Shear bond strength of each group was as follows: 1-(27.3Mpa), 2-(33.5Mpa), 3-(16.9Mpa) 4-(19.3Mpa). Statistical analysis proved that shear bond strength of used diamond bur prepared groups (2,4) was more than new diamond bur prepared ones (1,3). This statistical difference, specially, was seen between SE Bond groups (1,2) but not between single Bond groups (3,4). Also, shear bond strength of (SE Bond) bonded groups (1,2) were more significantly than (single Bond) bonded ones (3,4).Conclusion: This study show that Bur cutting efficiency influences composite - dentin shear bond strength especially when the adhesive is SE Bond (used bur> new bur) Also type of adhesive affects on composite - dentin shear bond strength. (SE Bond > Single Bond).

Background and Aim: Inducing anesthesia is one of the important tasks in dentistry. Among various techniques for injection, the Inferior Alveolar Nerve Block (IANB) technique is one of the most practical and prevalent methods. However, according to some proofs in reference books, the success rate for this technique is somehow low. Therefore the success rate of IANB performed by 10th-semester undergraduate students from Faculty of Dentistry of Tehran University of Medical Sciences was assessed in this study.Materials and Methods: In this cross-sectional study from patients referring to oral and maxillofacial surgery ward, 20 patients with predefined conditions were selected. For each of them, two IANB injections were done in two separated days; one by a student and the other by an attend (or resident) of maxillofacial surgery ward. Success or failure of each injection was examined by Pin Prick test. In this study, the non-parametric Willcoxon test was used.Results: In this study, the success rate of IANB was 70% and 90%, respectively for students and attends (or resident).Conclusion: Significant statistically difference was seen between the two groups, we hope that through further practical education, this differences rsduce in following similar studies.

Background and Aim: Black staining after taking iron drops on the primary teeth is always concern of parents. There is not an exact explanation for the mechanism of iron black staining. The purpose of this study was to compare tooth discolorations, atomic absorption and structural changes of primary teeth enamel caused by two kinds of iron drops[ Kharazmi (Iran) and Fer-in-sol(USA)].Materials and Methods: In this ex-vivo study, 93 sound primary teeth in normal color range were divided into five groups. Two groups of samples were immersed into the Artificial Caries Challenge(ACC) for two weeks before getting exposured to iron drops: Group 1 Control(NS): sound enamel teeth which were kept in Normal Saline environment(NS)(13teeth). Group 2 (NS-KH): NS, kharazmi iron drop (20 teeth). Group 3 (ACC-KH): ACC, Kharazmi iron drop (20teeth). Group 4 (NS-F-in-S): NS, Fer-in-Sol iron drop (20teeth). Group 5 (ACC-F-in-S): ACC, Fer-in-Sol iron drop. Visual tooth discolorations were determined by a specialist in operative dentistry who was not aware of experimental groups. The iron concentration was measured by ICP system (Vista-pro, Australia) and the structural changes were studied by SEM (Philips, Netherland). The data of discoloration were studied with Kruskal-Wallis test and multiple comparisons using Bonferroni type test, and with the data of atomic absorption were studied with oneway ANOVA test and Tukey HSD test.Results: The discoloration in the teeth immersed into the ACC (ACC-KH, ACC-F-in-S) was more severe than the sound enamel surface (NS-KH, NS-F-IN-S) (p<0.001) and Kharazmi iron drop caused more discoloration in the teeth immersed into the ACC (p=0.018). The teeth immersed into the ACC, absorbed more iron than the sound enamel surface (p<0.001) and also the teeth immersed into the ACC absorbed more Kharazmi iron drop (p<0.001). In the Scanning Electron Microscopy study, at low magnification in the sound teeth the perikymata was arranged regular. At low magnification in the teeth immersed into the ACC, many fractures were observed. The fractures in group 3(ACC-KH) were more and deeper.Conclusion: Being immersed into the ACC, caused more iron absorption, severe discoloration and structural changes in the enamel of primary teeth. Such changes were more distinct in the teeth exposed to Kharazmi iron drop than the teeth exposed to Fer-in-Sol iron drop.