Involvement of dopaminergic system in the dentate gyrus of the hippocampus in modulating the orofacial pain-related behaviors in the rats.

Chemical stimulation of the lateral hypothalamus (LH) induces analgesia by forming neural circuitries with multiple brain regions. The involvement of hippocampal dopaminergic receptors in the LH stimulation-induced antinociception in specific pain models in animals has been documented. However, because the neural circuitries involved in the mediation of orofacial pain are not the same as those that mediate the other types of pain, the present study aims to detect the role of dopamine receptors within the dentate gyrus (DG) in the antinociceptive responses induced by LH stimulation in an animal model of orofacial pain. Male Wistar rats (220-250 g) were implanted with two separate cannulae into the LH and DG on the same side. D1- or D2-like dopamine receptor antagonist, SCH23390, or sulpiride (0.25, 1, and 4 µg) were microinjected into the DG, five minutes before intra-LH injection of carbachol (250 nM). The animals were then injected with formalin 1% (50 µL; sc) into the upper lip lateral to the nose and subjected to the orofacial formalin test. Intra-DG administration of SCH23390 or sulpiride attenuated the antinociceptive responses induced by intra-LH microinjection of carbachol during the orofacial formalin test. The findings of the current study suggest that chemical stimulation of the LH modulates orofacial pain, possibly through activation of the DG dopaminergic neurons. Due to the high incidence and prevalence of orofacial pain in the general population, understanding how such neuronal circuitry modulates nociceptive processing will advance the search for novel therapeutics.

Postoperative endodontic pain of three different instrumentation techniques in asymptomatic necrotic mandibular molars with periapical lesion: a prospective, randomized, double-blind clinical trial.

OBJECTIVES: The purpose of this prospective, randomized, double-blind study was to compare postoperative pain of root canal treatment in patients with asymptomatic mandibular molar teeth with necrotic pulp and periapical lesion using three different instrumentation techniques: hand, multi-file rotary (ProTaper Universal), and reciprocating single-file (Wave-One) instrumentation techniques. MATERIALS AND METHODS: Ninety-six patients who fulfilled specific inclusion criteria were assigned to three groups according to the root canal instrumentation technique used: Hand (G1), ProTaper Universal (G2), and Wave-One (G3). One-visit root canal treatment was carried out, and the severity of the postoperative pain was assessed by the Heft-Parker visual analogue scale 6, 12, 18, 24, 48, and 72 h after treatment. Data were analyzed by Kruskal-Wallis, χ 2, Cochrane Q, one-way ANOVA, and Spearman's correlation analyses (α = 0.05). RESULTS: The patients in group 3 reported significantly lower postoperative pain levels at 6, 12, and 18 h compared with the patients in the two other groups (P < .05). In addition, the patients in group 2 reported significantly lower postoperative pain levels at 6 and 12 h compared with the patients in group 1 (P < .05). There were no significant differences in postoperative pain between the three groups at other time intervals (P > .05). The analgesic consumption was significantly higher in group 1 (P < .05), but no difference was seen between the two other groups (P > .05). CLINICAL RELEVANCE: Postoperative pain was significantly lower in patients undergoing root canal instrumentation with the Wave-One file compared with the ProTaper Universal and hand files.

Influence of Hand Instrumentation and Ultrasonic Scaling on the Microleakage of various Cervical Restorations: An in vitro Study.

INTRODUCTION: In cervical lesions, various restorative materials can be inserted, which can be affected by the application of periodontal scalers. This study evaluated and compared the marginal seal of class V glass ionomer, composite resin, and amalgam restorations after subjecting them to hand instrumentation and ultrasonic scaling. MATERIALS AND METHODS: In this experimental study, 30 sound human first premolars were selected. In each tooth, buccal and lingual cavities (4 mm mesiodistal width, 3 mm occlusogingival height, and 2 mm depth) were made. The teeth were randomly assigned to three groups of 10 teeth: (1) Glass ionomer group, (2) composite group, and (3) amalgam group. Teeth were subjected to thermocycling procedure for 1,000 cycles between 5 and 55°C water baths and a 1-minute dwell time. Then, each group was randomly subdivided: (1) Margins of 30 restorations were exposed to hand instrumentation procedures by applying 10 working strokes, (2) margins of 30 restorations were exposed to a periodontal tip mounted on a piezoelectric ultrasonic handpiece working at 25 kHz for 10 seconds. The specimens were serially sectioned mesiodistally. Each section was examined under a stereomicroscope. The extent of microleakage was ranked using a 0 to 4 scale at both occlusal and cervical margins of the restorations. Data were analyzed initially using the Kruskal-Wallis test, followed by multiple comparisons using the Mann-Whitney and Wilcoxon test. RESULTS: The type of restorative material had a significant influence on dye penetration, whether in the enamel margin or in the dentinal margin (p < 0.001). The microleakage of glass ionomer group was the highest. No statistical differences were found in dye penetration between scaling groups (hand instrumentation and ultrasonic scaling) (p > 0.05). CONCLUSION: Type of restorative material had a significant influence on microleakage. No statistical differences were found in dye penetration between scaling groups. CLINICAL SIGNIFICANCE: The microleakage of glass ionomer restoration is greater than amalgam and composite restorations after subjecting them to hand instrumentation and ultrasonic scaling.

Evaluation of the Effects of Dental Implants on Oral Lesions.

OBJECTIVE: To determine whether dental implants impress oral lesions, and to evaluate the nature of their effect on the lesions. MATERIALS AND METHODS: A comprehensive search was done via Google and PubMed for articles (including case reports and literature reviews) containing the keywords 'oral squamous cell carcinoma' (OSCC), 'oral lichen planus' (OLP), 'lichenoid contact reaction' (LCR), 'osseointegrated implants', and 'dental implants' , in the last 10 years (2002-2012). RESULTS: The study included 24 articles involving patients with dental implants, and some oral lesions (e.g. oral lichen planus and oral squamous cell carcinoma) or with a history of lesions. In these publications, there is evidence suggesting the possibility of emergence, exacerbation, recurrence, or even malignant transformation of the oral lesions after implant placement in some cases. CONCLUSION: Based on our review of the literature, implant treatment does not seem to be completely safe under any circumstances, but may have some complications in subjects with certain diseases (e.g. oral lesions, autoimmune diseases, malignancies, allergic reactions, etc.). Therefore prior to treatment, patients should be fully informed of the risks. CLINICAL SIGNIFICANCE: Implant treatment is best done with caution in patients with cancer or mucocutaneous disorders.

Prophylactic effect of topical (slow-release) and systemic curcumin nano-niosome antioxidant on oral cancer in rat.

BACKGROUND: Oral malignancies have a significant effect on the quality of life among the affected patients. Curcumin is an antioxidant with a low bioavailability in the target tissue. Niosomes are carriers of increasing the therapeutic effects of drugs and reducing their side effects. This study aimed to determine the effective dose of curcumin niosome in the culture and then to compare its prophylactic effect in the form of mouthwash with that of its injectable form on oral cancer in rats. METHODS: This was an in-vitro and in-vivo study. Firstly, KB oral cancer cells and human umbilical vein endothelial cells (HUVEC) were treated in separate groups with free curcumin, curcumin-loaded niosomes, and the unloaded niosomes at four doses of 4, 8, 16, and 32 µg. The study rats were then divided into the following four groups: 1) no intervention, 2) only carcinogenic substance, 3) carcinogenic substance with curcumin-loaded niosome injection, and 4) carcinogenic substance with a mouthwash containing niosome. RESULTS: At the cellular level, a dose of 16 µg after 24 h was selected as an effective dose. In the animal phase, the use of injectable curcumin niosome was observed to significantly prevent the development of severe forms of dysplasia. CONCLUSIONS: In this in-vitro and in-vivo study, curcumin-loaded niosome was effective in preventing the development of severe forms of dysplasia and the inhibition of the growth of cancer cells.

Effect of Different Surface Treatments and Pressure Conditions on Shear Bond Strength of Zirconia Ceramic to Composite Resin.

Objectives: The aim of this study was to assess the shear bond strength (SBS) of zirconia ceramic to composite resin with various surface treatments following pressure changes. Materials and Methods: Totally, 135 zirconia blocks were prepared by computer-aided design/computer-aided manufacturing technology. The samples were divided into 9 groups (n=15). Three surface treatments including sandblasting, tribo-chemical preparation, and laser application were used. For each method, 45 samples were considered and tested under different pressure conditions. Z-Prime Plus primer was used for bonding of all samples to composite cylinders. All specimens were stored in water for 24 h, underwent thermocycling, and were then placed in a pressure chamber under normal-, high-, and low-pressure conditions. Then, the SBS test was performed for each sample. Data were analyzed by two-way and one-way ANOVA (α=0.05). Results: The SBS was significantly higher in sandblasting and tribochemical preparation compared with laser irradiation (P<0.05). There was no statistically significant difference in SBS of sandblasting and tribochemical preparation methods (P>0.05). Sandblasting, tribochemical preparation, and laser methods did not show a significant difference in SBS at different pressures (P>0.05). Conclusion: Sandblasting and tribochemical preparation yielded a higher SBS than laser. Different pressures had no effect on SBS, irrespective of surface preparation method.

Oral manifestations in patients with diabetes mellitus.

The purpose of this article was to increase the knowledge about oral manifestations and complications associated with diabetes mellitus. An overview was performed on Google, especially in recent reliable papers in relation to diabetes mellitus and its oral manifestations (keywords were "diabetes mellitus", "oral manifestations", and "oral complications"). Data were collected and the results were declared. Diabetes mellitus is one of the most common chronic disorders characterized by hyperglycemia. This disease can have many complications in various regions of the body, including the oral cavity. The important oral manifestations and complications related to diabetes include xerostomia, dental caries, gingivitis, periodontal disease, increased tendency to oral infections, burning mouth, taste disturbance, and poor wound healing. Oral complications in diabetic patients are considered major complications and can affect patients' quality of life. There is evidence that chronic oral complications in these patients have negative effects on blood glucose control, so prevention and management of the oral complications are important.

Comparison of therapeutic effect of mucoadhesive nano-triamcinolone gel and conventional triamcinolone gel on oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a chronic disease without any definitive treatment. Local corticosteroids are often prescribed, but their efficacy has been questioned by many studies. The purpose of this study was to investigate the effect of nano-based triamcinolone acetonide gel (NT) and compare it with conventional triamcinolone gel (CT) on OLP. MATERIALS AND METHODS: In this triple-blind randomized clinical trial study, 40 patients with Erosive OLP were divided into two groups receiving (CT) and (NT). The patients were requested to apply them four times a day for 2 weeks. The severity of pain was evaluated through visual analog scale, the size of lesions was measured with paper lace, and the appearance of lesions was examined adopting Thongprasom scale . Findings will be significant via independent t-test or Chi-square test with P < 0.05. RESULTS: The severity of pain in NT group was 4.9 ± 0.7 cm before the treatment and 1.5 ± 0.9 after that, whereas in CT group, it was 4.9 ± 0.8 and 1.8 ± 0.9, respectively . The mean size of the lesions in NT group was 2.1 ± 1.1 cm before the treatment and 0.8 ± 1.1 afterward, whereas in CT group, was 2.2 ± 1.1 and 1.3 ± 1.1, respectively. The OLP appearance before and after the study in NT group was 4.5 ± 0.5 and 0.8 ± 0.6, respectively, whereas in CT group was 4.6 ± 0.5 and 0.9 ± 0.7 (P = 0.3). Among these variables, only Thongprasom scale on the 6th and 14th days had a significant reduction in NT group in comparison with CT group. CONCLUSION: NT has a better impact on OLP in comparison with CT, but this difference is not statistically significant.

Thoracic Kyphosis Angle in Relation to Low Back Pain among Dentists in Iran.

BACKGROUND: Non-specific low back pain (LBP) has a direct impact on the quality of life, active days at work and health care costs. AIM: This study was conducted to determine the relationship between LBP and thoracic kyphosis angle among dentists. MATERIAL AND METHODS: This cross-sectional and descriptive-analytical study carried out in the form of census among 84 dentists employed in a specialised clinic in Iran. Dentists LBP prevalence and intensity and thoracic kyphosis angle were evaluated respectively with the self-administered body map questionnaire, visual analogue scale and flexicurve ruler. Statistical data analysis was done using SPSS software, version 22. RESULTS: The data showed that the prevalence of LBP in dentists was 44.9% and intensity of LBP was reported about 71.9 ± 19.34. Pearson correlation coefficient between thoracic kyphosis angle and dentist's characteristics was not significant except for work experience. The single linear regression model showed that 1.3% of thoracic kyphosis angle changes was positively dependent on LBP. Also, the present study proved that thoracic kyphosis angle changes were positively dependent to 2.6%, 10.8% and 5.7 percent of age, work experience and Body Mass Index (BMI), respectively. CONCLUSION: Despite the lack of significant statistical relation between LBP and thoracic kyphosis angle, there is a high prevalence and intensity of LBP among Dentists. To reduce the risk of work-related LBP among dentists, managing factors such as BMI, work postures and exercises during work should be taken into consideration.

A boy with oral hair: case report.

In personal communication we have never seen or heard of hair being detected in the oral cavity. Even Julia Pastrana, the famous "Bearded Lady" of the 1800's, had no record of oral hair, although her entire body was covered with hair. Extensive records of her oral condition, including plaster models of her teeth have been preserved in the Odontological Museum of the Royal College of Surgeons in London city. She suffered from excessive gingival hyperplasia, but apparently no hair existed within the mouth. Some rodents have oral hair as a normal occurrence, but the condition is apparently limited in the animal kingdom. A case of hair occurring naturally in the mouth has been reported only twice previously. A third case of this rare anomaly is reported here. In this case, multiple hairs were found at the gingival sulcus in the labial, buccal, lingual and palatal tooth surfaces in an 11-year-old boy.

Extramedullary Plasmacytoma of the Oral Cavity in a Young Man: a Case Report.

Extramedullary plasmacytomas are rare solitary soft tissue tumors that arise from proliferations of malignant transformed monoclonal plasma cells and can be diagnosed through biopsy and histopathologic examination. These lesions are closely associated with multiple myelomas, which should be ruled out in all these cases by necessary laboratory and radiographic examinations. A 25-year-old man was referred to our clinic with a rapidly-growing painless lesion measuring about 2.5×3×3 cm in the palatal side of the left maxillary second and third molar teeth. A diagnosis of solitary plasmacytoma was made on the basis of clinical, radiographic, and histopathological findings. Early diagnosis of extramedullary plasmacytomas is of great importance. Radiotherapy is the common modality of treatment with or without adjuvant chemotherapy. Progression to multiple myeloma is possible; thus, close follow-up of the patient is essential after completion of the therapeutic procedure.

Comparison of therapeutic effect of mucoadhesive Nanotriamcinolone gel and conventional triamcinolone gel on recurrent aphthous stomatitis / Comparação do efeito terapêutico do gel mucoadesivo de nano-triancinolona e do gel convencional de triancinolona na estomatite aftosa recorrente

Objective: Recurrent aphthous stomatitis (RAS) is characterized by recurring ulcers, with well-defined margins. The lesions are confined to the oral mucosa (usually seen in non-keratinized mucosa). The disease manifests in the form of outbreaks, with a chronic and self-limiting course in most cases. Since the cause of the disease is unknown, many drugs have been studied to palliate the symptoms. Treatment used is multifocal and varies according to the predisposing factors. The aim of this study was to investigate the effect of recombinant Nano-based triamcinolone acetonide gel and compare it with conventional triamcinolone gel on RAS. Material and methods: In this triple-blind randomized clinical trial study, sixty patients with minor aphthous lesions were divided into two groups receiving conventional triamcinolone (CT) and Nano-based triamcinolone (NT). The patients were requested to apply drug four times a day for a week. The severity of pain (through VAS) and the size of the lesions (mean of the largest diameter of the lesions) were evaluated on starting day and days 2, 4, 6 after the intervention. Statistical analysis was performed using chi square and independent t-test. Findings were significant with P < 0.05. Results: Of the 60 patients enrolled in the study, 5 patients did not continue; 21 (38.2%) cases were female and 34 (61.8%) cases were male (P=0.6). The severity of pain in NT group before and after the study was 1.4 ± 5.2 and 1.8 ± 1.3 cm, respectively and in CT group was 48.1 ± 1 and 1.8 ± 1.3 cm. The size of the lesions in NT group before and at the end of the study was 0.96 ± 0.1 and 0.18 ± 0.1 cm, respectively and in CT group was 0.93 ± 0.1 and 0.19 ± 0.1 cm. Among the mentioned variables, only size of lesions on the 2nd and 4th days had a significant reduction in NT group in comparison with CT group. Conclusion: The size of lesions showed a significant reduction on the 2nd and 4th days in NT group in comparison with CT group, therefore NT has a better impact on RAS in comparison with CT. (AU)

Objetivos: A estomatite aftosa recorrente (EAR) é caracterizada por úlceras recorrentes, com margens bem definidas. As lesões estão confinadas à mucosa oral (geralmente vista em mucosa não queratinizada). A doença se manifesta na forma de surtos, com um curso crônico e autolimitado na maioria dos casos. Como a causa da doença é desconhecida, muitos medicamentos foram estudados para aliviar os sintomas. O tratamento utilizado é multifocal e varia de acordo com os fatores predisponentes. O objetivo deste estudo foi investigar o efeito do gel acetonido de triancinolona recombinante baseado em Nano e compará-lo com o gel de triancinolona convencional no EAR. Material e métodos: Neste estudo clínico randomizado triplocego, sessenta pacientes com lesões aftosas menores foram divididos em dois grupos que receberam triancinolona convencional (CT) e triancinolona Nano (NT). Os pacientes foram solicitados a aplicar droga quatro vezes ao dia durante uma semana. A gravidade da dor (por meio da EVA) e o tamanho das lesões (média do maior diâmetro das lesões) foram avaliados no dia inicial e nos dias 2, 4 e 6 após a intervenção. A análise estatística foi realizada utilizando teste qui quadrado e teste t independente. Os achados foram significativos com P < 0.05. Resultados: Dos 60 pacientes incluídos no estudo, 5 pacientes não deram continuidade; 21(38,2%) casos foram mulheres e 34 (61,8%) casos foram homens (P=0,6). A gravidade da dor no grupo NT antes e depois do estudo foi de 1,4 ± 5,2 e 1,8 ± 1,3 cm. O tamanho das lesões no grupo NT antes e ao final do estudo foi de 0,96 ± 0,1 e 0,18 ± 0,1 cm, respectivamente, e no grupo de TC foi de 0,93 ± 0,1 e 0,19 ± 0,1 cm. Entre as variáveis mencionadas, somente o tamanho das lesões no segundo e quarto dias tiveram uma redução significativa no grupo NT em comparação com o grupo CT. Conclusão: O tamanho das lesões mostrou uma redução significativa nos 2º e 4º dias no grupo NT em comparação ao grupo CT, portanto o NT tem um impacto melhor no RAS em comparação com o TC. (AU)