Microtensile bond strength of glass fiber posts cemented with self-adhesive and self-etching resin cements.

PURPOSE: To evaluate the bond strength of glass fiber posts to intraradicular dentin when cemented with self-etching and self-adhesive resin cements. MATERIALS AND METHODS: Forty-eight single-rooted human teeth were decoronated, endodontically treated, post-space prepared and divided into 8 groups (n = 6). The glass fiber posts used were: Exacto (EA) (Angelus) and everStick (ES) (StichTeck), which were cemented with two self-adhesive resin cements: BisCem (BIS) (Bisco) and Rely-X Unicem (UNI) (3M/ESPE), and two self-etching resin cements: Esthetic Cementing System NAC100 (NAC) (Kuraray) and Panavia-F (PAN) (Kuraray). Specimens were thermocycled between 5°C and 55 °C for 1000 cycles and stored in water at 37°C for 1 month. Four 1-mm-thick (in cross section) rods were obtained from the cervical region of the roots. Specimens were then subjected to microtensile testing in a special machine (BISCO; Schaumburg, IL, USA) or a crosshead speed of 0.5 mm/min. Microtensile bond strength (µTBS) data were analyzed with two-way ANOVA and Tukey's tests. RESULTS: Means (and SD) of µTBS (MPa) were: EA/PAN: 10.3 (4.1), EA/NAC: 14 (5.1) EA/BIS: 16.4 (4.8), EA/UNI: 19.8 (5.1), ES/PAN: 25.9 (6.1), ES/NAC: 29.1 (7), ES/BIS: 28.9 (6), ES/UNI: 30.5 (6.6). ANOVA indicated significant differences among the groups (p < 0.001). Mean µTBS values obtained with ES post were significantly higher than those obtained with EA (p < 0.001). For EA, Tukey's test indicated that higher µTBS means were obtained with the self-adhesive resin cements (BIS and UNI), which were statistically significantly different (p < 0.05) from values obtained with the self-etching resin cements (PAN and NAC). Different cements had no significant effects on the bond strength values of ES post (p > 0.05). µTBS values obtained with ES post were significantly higher than those obtained with EA post irrespective of the resin cement used. CONCLUSION: everStick posts resulted in the highest mean µTBS values with all cements. Self-adhesive cements performed well in terms of bond strength.

Unusual anatomy of a maxillary first molar with two palatal roots: a case report.

The success of endodontic therapy is based on good endodontic access, correct cleaning and shaping, and adequate root canal obturation. However, endodontic treatment is also dependent on a sound knowledge of the internal anatomy of human teeth, especially when anatomical variations are present. Certain anatomical changes may be present to varying degrees, and it is important to report these to improve the understanding and expertise of endodontic specialists. With this aim in mind, this study reports an example of a maxillary first molar showing unusual anatomy (four roots and six root canals) and describes the endodontic treatment that was employed.

Analysis of the internal anatomy of maxillary first molars by using different methods.

The success of endodontic treatment depends on the identification of all root canals so that they can be cleaned, shaped, and obturated. This study investigated internal morphology of maxillary first molars by 3 different methods: ex vivo, clinical, and cone beam computed tomography (CBCT) analysis. In all these different methods, the number of additional root canals and their locations, the number of foramina, and the frequency of canals that could or could not be negotiated were recorded. In the ex vivo study, 140 extracted maxillary first molars were evaluated. After canals were accessed and detected by using an operating microscope, the teeth with significant anatomic variances were cleared. In the clinical analysis, the records of 291 patients who had undergone endodontic treatment in a dental school during a 2-year period were used. In the CBCT analysis, 54 maxillary first molars were evaluated. The ex vivo assessment results showed a fourth canal frequency in 67.14% of the teeth, besides a tooth with 7 root canals (0.72%). Additional root canals were located in the mesiobuccal root in 92.85% of the teeth (17.35% could not be negotiated), and when they were present, 65.30% exhibited 1 foramen. Clinical assessment showed that 53.26%, 0.35%, and 0.35% of the teeth exhibited 4, 5, and 6 root canals, respectively. Additional root canals were located in this assessment in mesiobuccal root in 95.63% (27.50% could not be negotiated), and when they were present, 59.38% exhibited 1 foramen. CBCT results showed 2, 4, and 5 root canals in 1.85%, 37.05%, and 1.85% of the teeth, respectively. When present, additional canals showed 1 foramen in 90.90% of the teeth studied. This study demonstrated that operating microscope and CBCT have been important for locating and identifying root canals, and CBCT can be used as a good method for initial identification of maxillary first molar internal morphology.

Avaliação da microbiota salivar de pacientes pediátricos com e sem diabetes melito do tipo 1 / Evaluation of salivary microbiota of pediatric patients with and without mellitus type 1 diabetes

Diabetes melito é uma doença metabólica que pode ocorrer na infância e na adolescência como resultado da deficiência de insulina, de resistência periférica ou ambos. Sua inter-relação com a odontologia se dá por intermédio de vários sinais e sintomas na cavidade bucal, além de aumentar o risco de doenças periodontais e cárie dental. O objetivo deste estudo foi avaliar microbiologicamente a saliva de crianças com ou sem diabetes. Amostras salivares foram coletadas e plaqueadas em kits de laminocultivo específicos para Lactobacillus e S. mutans, incubadas e contadas conforme instruções do fabricante (Laborclin). Na contagem de Lactobacillus observaram-se médias de 4,5 e 3,5 no log10 (p=0,01), em crianças com e sem diabetes, respectivamente. Na contagem de S. mutans foram obtidas médias de 4,1 e 3,7 no log10 (p=0,11) em crianças com e sem diabetes, respectivamente. Pode-se concluir que crianças com diabetes abrigam uma contagem maior de Lactobacillus salivar do que crianças sem a doença

Diabetes mellitus is a metabolic disease that can occur in childhood and adolescence as a result of insulin deficiency, of peripheral resistance or both. Signs and symptoms in the oral cavity correlate this disease to dentistry, besides the increase of periodontal diseases and dental caries. The aim of this study was to evaluate the saliva of children with and without diabetes mellitus type 1 (DM-1). Salivary samples were collected and tested with culture kits for Lactobacillus and S. mutans, incubated and counted as manufacturer instructions (Laborclin®). Results achieved means of 4.5 and 3.5 (log10 and p = 0,01) for Lactobacillus in DM-1 children and normal children, respectively. S. mutans counts revealed means of 4.1 and 3.7 (log10 and p = 0,11) for DM-1 children and normal children, respectively. Statistically, it is possible to conclude that pediatric patients with diabetes mellitus type 1 have greater counts of salivary Lactobacillus than normal children