Cytotoxicity evaluation of four endodontic sealers

This study evaluated in vitro the cytotoxicity of four root canal sealers (Topseal, EndoRez, TubliSeal and Kerr Pulp Canal Sealer E.W.T.) and their effects on reactive oxygen/nitrogen intermediate induction by mouse peritoneal macrophages. Thioglycollate-induced cells were obtained from Swiss mice by peritoneal lavage with 5 mL 10 mM phosphate-buffered saline, washed twice and resuspended (10(6) cells/mL) in appropriate medium for each test. Cytotoxicity was determined by the presence of hydrogen peroxide (H2O2) and nitric oxide (NO) by the peroxidase-dependent oxidation of phenol red and Griess reaction, respectively. Sealer suspensions were obtained in two different concentrations from each material: 18 mg/mL and 9 mg/mL, established according to compatibility parameters following MTT assay. Comparing the sealers, H2O2 release at concentrations of 9 mg/mL and 18 mg/mL was similar: Topseal > positive control (medium + cells + 5 mg/mL zimozan solution) > EndoRez > TubliSeal > Kerr Pulp E.W.T. > negative control (medium + cells). NO release at concentration of 9 mg/mL was: positive control (medium + cells + 10 microg/mL LPS solution) > Topseal > Kerr Pulp E.W.T. > TubliSeal = EndoRez > negative control (medium + cells); at concentration of 18 mg/mL was: positive control > Topseal > Kerr Pulp E.W.T > TubliSeal > EndoRez > negative control. Based on the results, it may be concluded that Topseal presented the highest cytotoxicity among the tested sealers, releasing higher concentrations of NO and H2O2 in macrophage culture.     

Toothache prevalence and associated factors: a life course study from birth to age 12 yr

This study estimated the lifetime prevalence of toothache at ages 6 and 12 yr, the prevalence of toothache during the last month, and their association with social, behavioural and clinical exposures in the course of life of 339 12-yr-old children from a birth cohort in Pelotas, Brazil. Exploratory variables were collected in the perinatal study and during several follow-up studies. Prevalence ratios were calculated using Poisson regression, following a hierarchical conceptual model. The lifetime prevalence of toothache at ages 6 and 12 yr were 39% [95% confidence interval (CI) = (34;45)] and 63% [95% CI = (58;69)], respectively. Toothache during the last month was reported by 11% [95% CI = (8;15)]. Children who did not live with their biological father at birth, and children with higher dmf-t counts, reported a higher lifetime prevalence of toothache at age 6 yr. Children experiencing poverty between ages 0 and 4 yr, with higher dmf-t and DMF-T indexes presented a greater lifetime prevalence of toothache at 12 yr. Toothache within the last month was more likely to be reported by girls and by children who did not live with their biological father at birth. Preventive strategies should be implemented in early stages of the life cycle, taking into account the socio-economic and family context in which pain mostly occurs.     

Effect of enamel matrix proteins on the treatment of intrabony defects: a split-mouth randomized controlled trial study

The objective of this split-mouth, double-blind, randomized controlled trial was to compare the clinical effect of treatment of 2- or 3-wall intrabony defects with open flap debridement (OFD) combined or not with enamel matrix proteins (EMP). Thirteen volunteers were selected with one pair of or more intrabony defects and probing pocket depth (PPD) > or = 5 mm. All individuals received instructions regarding oral hygiene and were submitted to scaling and root planing. Each participant received the two treatment modalities: test sites were treated with OFD and EMP, and control sites received only OFD. After 6 months, a significant reduction was observed in PPD for the EMP group (from 6.42 +/- 1.08 mm to 2.67 +/- 1.15 mm) and for the OFD group (from 6.08 +/- 1.00 mm to 2.00 +/- 0.95 mm) (p < 0.0001), but with no significant difference between groups (p = 0.13). A significant gain in relative attachment level (RAL) was observed in both groups (EMP: from 13.42 +/- 1.88 mm to 10.75 +/- 2.26 mm, p < 0.001; OFD: from 12.42 +/- 1.98 mm to 10.58 +/- 2.23 mm, p = 0.013), but with no significant difference between groups (p = 0.85). Gingival recession (GR) was higher in the EMP group (from 1.08 +/- 1.50 mm to 2.33 +/- 1.43 mm; p = 0.0009) than in the OFD group (from 0.66 +/- 1.15 mm to 1.16 +/- 1.33 mm; p = 0.16), but this difference was not significant (p = 0.06). In conclusion, the results showed that OFD combined with EMP was not able to improve treatment of intrabony defects compared to OFD alone.     

The physical characterization of a thermoplastic polymer for endodontic obturation

OBJECTIVE: To analyze a new endodontic sealer material commercially known as Resilon and to describe in detail the experimental techniques employed that lead to the identification of the composite material. METHODS: An extensive structural, thermal, and physical characterization was used to identify a new endodontic sealer material using the following techniques: Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) analysis, X-ray fluorescence spectrometry (XRF) technique, X-ray diffraction (XRD) measurement, thermo-gravimetric analysis (TGA) and a differential scanning calorimeter (DSC). The surface morphology was analyzed using a scanning electron microscope (SEM). RESULTS: The material was identified as a composite of polycaprolactone, which is a polymer of the polyester family and bioactive glass, which is radiopaque filler. CONCLUSIONS: The Resilon sealer material is a thermoplastic synthetic degradable polymer (polycaprolactone), it contains bioactive glass. Its properties, such as strength, modulus, shape-memory effect and biodegradability depend on the crystalline fraction, which is affected in turn by conditions of crystallization. Investigation of the crystallization kinetics of PCL is of practical significance. It is especially necessary to study its the dynamic and non-isothermal crystallization process.     

Multiple hyperdontia: Report of an unusual case

Supernumerary teeth are an infrequent developmental anomaly that can appear in any area of the dental arch and can affect any dental organ. Multiple supernumerary teeth, or hyperdontia, is rare in people with no other associated diseases or syndromes. Conditions commonly associated with hyperdontia include cleft lip and palate, trichorhinophalangeal syndrome, cleidocranial dysplasia, and Gardner's syndrome. A black girl, aged 11 years 8 months, came for consultation; radiographs showed 81 teeth: 18 deciduous, 32 permanent, and 31 supernumerary. The main concern initially was to determine whether she was syndromic, and she was referred to a geneticist. G banding analysis showed pericentric inversion of chromosome 9; the chromosome formula was 46, XX, inv (9) (p13q21). Orthodontic treatment for this patient will be a clinical challenge because of the great number of teeth to be extracted and the alterations in the shapes of the teeth. Treatment goals should be established by a multidisciplinary team, where oral surgeon, orthodontist, periodontist, and prosthodontist come together to solve a medical and dental puzzle, eliminating the pieces that do not fit and searching for new ones to obtain an occlusion that will give the patient physiologic conditions of normality and esthetic satisfaction.     

Influence of resin composite shade and location of the gingival margin on the microleakage of posterior restorations

OBJECTIVE: The objective of this in vitro study was to evaluate the influence of resin composite shade and location of the gingival margin (enamel or dentin) on the microleakage of proximal restorations on posterior teeth. Methods and MATERIALS: Sixty freshly extracted human third molars were prepared with standardized Class II box-shaped cavities with proportional size and shape, with distal gingival margins located on the enamel and mesial gingival margins on dentin. The teeth were randomly divided into 6 groups according to resin shade (n=10): G1-Incisal; G2-A1; G3-A2; G4-A3; G5-A3.5; G6-A4. The cavities were restored with a total-etch 1-bottle adhesive system and microhybrid resin composites inserted in 4 increments, light cured for 20 seconds through the occlusal surface, then an additional 60 seconds for each surface. After 1 week of immersion in distilled water, the specimens were thermocycled (500 cycles, 5 degrees -55 degrees C, 30 seconds dwell time), sealed with nail polish and immersed in 0.5% basic fuschin solution for 24 hours. The restorations were sectioned longitudinally, and microleakage was evaluated using a 0-3 score scale. RESULTS: Data were subjected to Kruskal-Wallis and Wilcoxon tests at p<0.05. No statistically significant differences between groups were observed regarding the shade of resin composite (p=0.8570). When margins (enamel or dentin) were considered separately, statistically significant differences were observed between groups (p<0.0001), with enamel margins exhibiting lower degrees of microleakage. CONCLUSION: The variation of resin composite shades utilized in this study did not influence the microleakage of Class II restorations. However, the location of the gingival margin influenced the microleakage.     

Oral myiasis: a case report

Oral Myiasis is a rare pathology in humans and is associated with poor oral hygiene, alcoholism, senility, suppurating lesions, severe halitosis and others conditions. The treatment is a mechanical removal of the maggots one by one but a systemic treatment with Ivermectin, a semi-synthetic macrolide antibiotic, have been used for treatment for oral myiasis. We present a case report of a 32-year-old man indigent, alcohol-dependent with an extensive necrotic area and acute swelling in upper lip and fetid odor. The patient's management included topic use of gentian violet, oral therapy with ivermectin (6 mg orally), surgical exploration to remove the larvae and necrotic tissue. After the complete larvae removal the swelling and the wounds were healing normally, the patients was referred to plastic surgery to repair tissue damage. The prevention of human myiasis is by education, but unfortunately in the developing countries some people live in low social condition, predisposing the occurrence of the infestation.     

Allergic contact dermatitis associated with the use of facemask on a patient with a history of atopy

Allergic contact dermatitis (ACD) is a skin inflammation caused by an allergic reaction after contact with small external substances capable of being absorbed by the skin. There are several studies describing allergic reactions to intraoral orthodontic appliances, especially those containing nickel. Allergic reactions due to extraoral appliances are not as frequent, and there are relatively few studies about them. Extraoral eactions are attributed to metallic, elastic, or textile parts of the extraoral appliances. This article's purpose was to report the appearance of an allergic contact dermatitis reaction in a 9-year, 2-month-old female patient, with a history of atopic dermatitis, after an orthodontic facemask was fitted. Rapid maxillary expansion was also performed with a Hyrax appliance while a facemask was used. Early diagnosis of this pathology is essential in order to achieve a total regression of the reaction. Orthodontists should be aware that ACD can be caused by facemasks in predisposed patients.