Dissolving efficacy of eucalyptus and orange oil, xylol and chloroform solvents on different root canal sealers.

AIM: To evaluate the solubility of five root canal sealers in orange oil, eucalyptol, xylol and chloroform solvents. METHODOLOGY: The solubility of RoekoSeal, Sealer 26, Epiphany, Endomethasone and EZ-Fill sealers was assessed in orange oil, eucalyptol, xylol, chloroform and distilled water. Seventy-five samples of root canal sealers were prepared and then divided into five groups for immersion in solvent for 2, 5 or 10 min. The means of loss weight were determined for each material in each solvent at all immersion periods, and the values were compared by factorial analysis of variance (anova) and SNK multiple comparisons. RESULTS: In the orange and eucalyptus oil groups, there was no significant difference among RoekoSeal, Sealer26, Epiphany and EZ-Fill at the three immersion periods (P > 0.05). With xylol, no significant differences were found at 5 and 10 min (P > 0.05) for each root sealer. Orange and eucalyptus oil solvents were as effective as chloroform at 2 min in dissolving all the root sealers. CONCLUSIONS: Xylol was the most effective solvent followed by the chloroform and the essential oils (eucalyptol and orange oil). Orange oil behaved in a similar way to eucalyptus oil.

Topographical evaluation of the major apical foramen in permanent human teeth.

AIM: To determine the distance from the anatomical root apex to the major apical foramen and the position of the major foramen on the root apex. METHODOLOGY: Crowns of 926 human teeth were sectioned at the cementum-enamel junction. Specimens were mounted on microscope slides for measurement parallel to the long axis of the teeth. The major foramen was identified as the largest-diameter opening at the root apex. A total of 1331 root specimens were evaluated using an optical stereomicroscope to an accuracy of 0.01 mm at 40 x (+/-10) magnification. The distance from the anatomical apex to the most apical point of the major foramen was measured, and its location (central, buccal, lingual, mesial and distal) was recorded. RESULTS: The mean distance between the major foramen and the anatomical root apex was 0.69 mm; the mean distance was larger in posterior teeth (0.82 mm) and smaller in anterior teeth (0.39 mm). A wide range of anatomical apex to major foramen distances were observed in all tooth groups: the greatest distance was in maxillary molars (0.95 mm) followed by mandibular pre-molars (0.87 mm) and mandibular molars (0.80 mm). The major foramen was at the tip of the root in 40% of teeth. The most frequent deviations of the foramen were to the buccal (20%) and distal (14%). CONCLUSION: In this sample of teeth without apical resorption the distance between the major foramen and the anatomical root apex was always <1 mm. Deviation of the major foramen from the anatomic apex varied widely amongst tooth groups.

An in vitro study of coronal leakage after intraradicular preparation of cast-dowel space.

STATEMENT OF PROBLEM: Coronal leakage can produce contamination of periapical tissues, resulting in endodontic failure. PURPOSE: The purpose of this in vitro study was to evaluate the ability of 2 sealers to prevent coronal leakage in canals filled with gutta-percha and prepared for cast dowels but without coronal sealing. MATERIAL AND METHODS: The crowns of 60 extracted single-rooted teeth were amputated. The root canals were prepared corono-apically and filled with gutta-percha cones and 1 of 2 different endodontic sealers: a resin-based sealer (AH Plus) and a calcium hydroxide-based sealer (Sealapex). Specimens were then stored in water for 7 days to allow the sealers to set. The specimens were prepared in 1 of 2 ways: no preparation for cast dowel or preparation of cast-dowel space (n=15). External surfaces of the roots were sealed with cyanoacrylate cement. The teeth were thermal cycled at 5 degrees and 55 degrees C in water baths (dwell time=30 seconds) for 500 cycles. Specimens were then submerged in 2% methylene blue colorant for 24 hours. Microleakage was measured according to the percentage of area stained with the colorant. Effects of each factor (cast-dowel preparation and type of sealant) on microleakage were analyzed by the Student t test (alpha=.05). RESULTS: The AH Plus and Sealapex sealers with cast-dowel preparation resulted in significantly (P<.001) more leakage compared to sealers with no dowel preparation. CONCLUSION: Cast dowel-space preparation had a negative influence on the sealing ability of the remnant root-canal filling material.

Decalcification of root canal dentine by citric acid, EDTA and sodium citrate.

AIM: To measure the demineralization capability of 1 and 10% citric acid, 10% sodium citrate and 17% EDTA during immersions of 5, 10 and 15 min on root canal dentine. METHODOLOGY: Crowns were sectioned from eight maxillary canines. The cementum was removed from the cervical third of the roots to expose the dentine. Canals were prepared using a handpiece-mounted Largo Peeso reamer. A 3-mm thick cross-sectional slice was obtained from the cervical third of each root. Each slice was sectioned into four equal parts. These specimens were assigned to one of four groups (n = 8) for the application of 1% citric acid, 10% citric acid, 10% sodium citrate or 17% EDTA. Each specimen underwent three successive 5-min immersions in each solution at room temperature. The solutions were not renewed between immersions. Two millimetres of solution were collected from the extracts and lanthanum oxide was added for the calcium reading by spectrophotometry. To compare the amounts of calcium removed by each solution, the Friedman test was used for the global comparison and the Wilcoxon test for paired comparisons. Differences between groups were evaluated using the Kruskal-Wallis test for the global comparison and Mann-Whitney test for paired comparisons. RESULTS: Overall, 1 and 10% citric acid were more effective than EDTA or sodium citrate at the three immersion times (P < 0.001); 10% citric acid was more effective than 1% citric acid (P < 0.001). EDTA and 1 and 10% citric acid showed decreasing effectiveness with time, and the decrease was significant for citric acid at both concentrations (P < 0.001). Although sodium citrate removed little calcium during the three time periods, the small increase recorded was significant (P < 0.01). CONCLUSIONS: Citric acid at 10% was the most effective decalcifying agent, followed by 1% citric acid, 17% EDTA and 10% sodium citrate.

Influence of time and thermocycling on marginal sealing of several dentin adhesive systems.

This study evaluated the in vitro microleakage of six dentin adhesive systems. Triangle-shaped Class V cavities with coronal margin in enamel and gingival margin in cementum or root dentin were cut in the buccal surfaces of 90 non-carious single-root human teeth. These teeth were randomly assigned into six groups (n = 15) for the evaluation of six different dentin adhesive systems: One Step, Prime & Bond 2.0, Syntac Single, Single Bond, Optibond Solo and Syntac Sprint. The preparations were restored with Degufill Ultra composite and polished using the Enhance system. Each group was randomly divided into three subgroups (n = 5): samples of the first subgroup were immersed in 2% methylene blue solution for seven days; those of the second subgroup remained in a similar solution for 31 days; those of the third subgroup were thermocycled 500x at 5-55 degrees C and immersed in 2% methylene blue for seven days. All 90 teeth were then embedded in methacrylate and bucco-lingually sectioned; the dye penetration was evaluated using an 0-4 ordinal scale. All of the dentin adhesive groups showed minimal leakage at the enamel margins with increased leakage at the gingival margins. Optibond Solo showed the best outcomes among the dentin adhesives tested.

[Dementia syndrome and risk factors in adults older than 60 years old residing in Habana]. / Síndrome demencial y factores de riesgo en adultos mayores de 60 años residentes en La Habana.

INTRODUCTION: The dementias and Alzheimer's disease are a growing problem in countries with a long life expectancy. OBJECTIVE: To find the prevalence of the dementia syndrome in the population aged over 60 years in the municipality of Marianao, La Habana, during the first three months of 1998, and the relationship with certain associated biosocial factors. PATIENTS AND METHODS: A descriptive transversal study in which 799 elderly persons were assessed in their homes, out of a population of 22,590 elderly persons, by means of conglomerate sampling in two stages. In the same way, we selected a sample from the municipality of Bauta representing 340 adults. The probable diagnosis of dementia syndrome or Alzheimer's disease was based on criteria of DSM III R and NINCDS-ADRDA. A second analytical phase was done by studying cases and witnesses. Univariate and multivariate hypothesis tests were done by means of the multiple logistic regression method. RESULTS AND CONCLUSIONS: The prevalence of the dementia syndrome was 8.2% (6.27-10.42); and that of Alzheimer's disease and vascular dementia was 5.13% and 1.93% respectively. Age, female sex, previous clinical history and no spouse (due to widowhood or being single), were risk factors in this population. Early detection of the dementia syndrome allows development of projects to intervene in old people to actively improve their state of health and socio-familial adaptation.

[Identification of caprine arthritis encephalitis virus using histopathological, immunohistochemica, and ultrastructural examination of tissues from seropositive goats in Mexico]. / Identificación del virus de la artritis encefalitis caprina mediante el estudio histopatológico, inmunohistoquímico y ultraestructural, en tejidos de cabras seropositivas en México.

This study demonstrated the presence of viral particles suggestive of arthritis-encephalitis virus through the clinic, serologic, pathologic, immunohistochemic and ultrastructural studies in dairy goats. In the postmortem studies the tissues used were: synovial membrane, lungs and mammary gland from goats with clinical signs characteristic of the disease and positive for serum antibodies to the virus.