Gustavo de Deus

Penetração intratubular de cimentos endodônticos

The purpose of this study was to evaluate the capacity of penetration of four endodontic sealers (Endo Fill, Sealapex, AH Plus and Pulp Canal Sealer) into dentinal tubules. Seventy-two extracted human maxillary anterior teeth were utilized in this study. The teeth were cleaned and shaped by means of the balanced-forces technique. The work length was established at 1 mm beyond the apex. Copious irrigation with 10 ml of 5.25% sodium hypochlorite was carried out. The teeth were divided in 8 groups - 4 had the smear layer maintained, and 4 had it removed. The smear layer was removed with a commercial solution of 17% EDTA, and the root canal system was flushed for 3 min. Finally, the roots were irrigated with 3 ml of 5.25% sodium hypochlorite. All teeth were sealed by means of the technique of the condensation wave with a medium nonstandardized cone. After filling, the roots were grooved, longitudinally split and examined under a scanning electron microscope (SEM). The focus of observation was the interface between the dentin and the sealing material. The Rickert sealer (Pulp Canal) presented the maximum penetration depths into the dentinal tubules, and Sealapex, the minimum. The Spearman test was used to determine whether there were significant differences between the groups. The removal of smear layer allowed significant penetration of the sealers (p £ 0.01).

Analysis of the sealing ability of different obturation techniques in oval-shaped canals: a study using a bacterial leakage model

The aim of this study was to evaluate the sealing ability of 3 obturation techniques in oval canals using a bacterial leakage model. Seventy mandibular incisors with oval canals were selected after buccolingual and mesiodistal radiographs, and divided into three groups. After instrumentation, the canals were obturated respectively by lateral condensation (G1), warm vertical condensation (G2) and Thermafil (G3). Five root canals were not obturated and served as positive controls; five teeth with intact crowns served as negative controls. All teeth were mounted on a 2 chamber apparatus and then exposed to human saliva. The number of days required for the entire contamination of the root canals was recorded, observing the turbidity of the BHI broth, for a period of 100 days. 84.21% of the samples from the lateral condensation group (G1); 84.21% of the samples from the warm vertical condensation group (G2); and 89.47% of the samples from the Thermafil System group (G3) showed no contamination at the end of the study. No statistical significant difference was found among the three techniques. The quality of the apical seal in the three techniques tested was similar.

The influence of the surgical operating microscope in locating the mesiolingual canal orifice: a laboratory analysis

The aim of this study was to evaluate the influence of using the surgical operating microscope (SOM) for detection of the mesiolingual (ML) canal orifice in extracted first maxillary permanent molars. One hundred and eight human first maxillary permanent molars were randomly selected and mounted onto a dental chair mannequin. Conventional access cavity was prepared and an attempt was made to locate the mesiolingual canal orifice using only a sharp explorer, a mirror and a #10 K-file. A mesiolingual canal orifice was either located or not located. If not located, the teeth were then evaluated by using a surgical operating microscope (SOM). The mesiobuccal roots of all teeth where the ML canal orifice had not been located were sectioned in an axial plane and the sections were explored with an adjunctive use of the SOM at a 25 X magnification. ML canal orifices were detected in 58 teeth using only a sharp explorer, a mirror and #10 K-file. In the remaining 50 teeth, 37 ML canal orifices were located by using the SOM and 3 ML canal orifices were located after root sectioning. In 10 teeth, the ML canal orifices were not found. The results of this study showed a high incidence of a ML canal in the mesiobuccal roots of the first maxillary molars (90.7%) and demonstrated that the adjunctive use of the SOM increased the ability of the dental clinician to locate the ML canal orifice.

Analysis of the film thickness of a root canal sealer following three obturation techniques

The aim of this study was to obtain a quantitative analysis of the film thickness of a root canal sealer formed after filling by three different techniques. Thirty human maxillary incisors were selected and access cavities were prepared using high-speed diamond stones and water spray. A size #15 K-Flexofile was introduced in the canal of each specimen until it was seen just at the apical foramen. The working length was determined to be 1 mm short of that position and the canals were prepared to an apical size of #45 K-Flexofile. Copious irrigation with 5.25% NaOCl (sodium hypochlorite) was used during and after instrumentation. The samples were divided into three groups and obturated as follows: G1 - lateral condensation, G2 - lateral condensation with an accessory cone, and G3 - continuous wave of condensation. The samples were evaluated in the cervical, middle and apical thirds. The film thickness of the root canal sealer was measured through a microscopic evaluation. Statistical analysis was obtained using the Wilcox test. Statistical analysis showed significant differences between G3 and G1, G3 and G2 (p < 0.05). In general, the lowest film thickness was observed in the continuous wave of condensation (G3). Lateral condensation with an accessory cone (G2) and lateral condensation (G1) demonstrated poorer results in this study, showing a higher film thickness. The small film thickness of the sealer obtained by the continuous wave of condensation technique may increase the clinical performance of this technique.

Ansiedade odontológica: nível, prevalência e comportamento - doi:10.5020/18061230.2004.p51

Literature reveals very devoid regarding dental anxiety in the brazilian population. The purposal of this study was to evaluate the dental anxiety expressed among pacients undergoing dental treatment at the University of Fortaleza, Ceara, Brazil, considering social parameter, past dental experience, time of last visit to dentist, and tooth related simptoms. A total of 300 individuals (150 male and 150 female) selected at random responded to a questionary containing the dental anxiety scale (DAS) and to questions about their socio-economic level and their behavior with respect to dental treatment. The mean DAS score for the sample was 11,65±0,15 (11,8±0,21 for women and 11,5±0,21 for men). Individuals with scores of 15 or more were considered anxious, and their prevalence in the sample was 18%. Comparision of normal and anxious individuals showed that there was no difference in their distribution in relation to educational level or monthly family income, but that anxious individuals avoid dental treatment more frequently either by failing to appear for their visits or looking for a dentist after longer periods of time.