Effect of Arnica montana 6 cH on edema, mouth opening and pain in patients submitted to extraction of impacted third molars

This study had the objective to evaluate the homeopathic action of Arnica montana 6 cH and placebo on edema, mouth opening (trismus) and pain in patients submitted to extraction of bilaterally impacted lower third molars. The experiment was carried out as a crossover and double-blind study. The data showed that edema was significantly reduced by the treatment with Arnica montana 6 cH (p<0.05) and did not demonstrate significant effect on trismus and pain as compared to control group.

Automatic extraction of road seeds from high-resolution aerial images

This article presents an automatic methodology for extraction of road seeds from high-resolution aerial images. The method is based on a set of four road objects and another set of connection rules among road objects. Each road object is a local representation of an approximately straight road fragment and its construction is based on a combination of polygons describing all relevant image edges, according to some rules embodying road knowledge. Each one of the road seeds is composed by a sequence of connected road objects, in which each sequence of this type can be geometrically structured as a chain of contiguous quadrilaterals. Experiments carried out with high-resolution aerial images showed that the proposed methodology is very promising in extracting road seeds. This article presents the fundamentals of the method and the experimental results, as well.

Development of a supercritical fluid extraction method for simultaneous determination of organophosphorus, organohalogen, organonitrogen and pyretroids pesticides in fruit and vegetables and its comparison with a conventional method by GC-ECD and GC-MS

The aim of this paper was to apply a multiresidue method using Supercritical Fluid Extraction (SFE) and capillary gas chromatography with electron capture and mass spectrometry detections in the analysis of the levels of pesticide residues in fruits and vegetables. Single laboratory validation of both solid-liquid and supercritical fluid extraction methods was carried out for 32 compounds selected from four pesticide classes (organochlorine, organonitrogen, organophosphorus and pyretroid) in blank and fortified samples of fresh lettuce, potato, apple and tomato. Recoveries for the majority of pesticides from fortified samples at fortification level of 0.04-0.10 mg kg -1 ranged 74-96% for both methods and confirmation of pesticide identity was performed by gas-chromatography-mass spectrometry in a selected-ion monitoring mode. Both methods showed good limits of detection (less 0.01 mg kg-1, depending on the pesticide and matrix) and the SFE method minimized environmental concerns, time, and laboratory work. ©2005 Sociedade Brasileira de Química.

Intercommissural width in 4 racial groups as a guide for the selection of maxillary anterior teeth in complete dentures

Purpose: To determine whether intercommissural width is a reliable guide for the selection of maxillary denture teeth width. Materials and Methods: Casts were made of 160 subjects from 4 different racial groups. Locations of intercommissural width landmarks (the corners of the mouth) were made on the subjects and transferred to the casts. The distances between the corners of the mouth and the distal of the canines were measured on the casts and compared. Results: A weak correlation was found between the distal of the canines and the distance between the corners of the mouth in the 4 racial groups. Conclusion: The use of the corners of the mouth for the selection of artificial teeth is generally inaccurate.

Evaluation of the effects of different extraction methods for main volatile compounds from Bambusa textilis leaves

Bambusa textilis is widely used in popular medicine to treat all kinds of wound inflammation, chronic fever, pulmonary and infectious diseases. The aim of this study was to compare the chemical composition of the extracts of B. textilis leaves obtained by three different extraction methods: solid/liquid extraction, Soxhlet and Clevenger system using gas chromatography with flame ionization detector (GC-FID) and gas chromatography with mass spectrometry (GC-MS) analyses. The analytical characteristics of the extracts showed some differences and the GC-MS analysis indicated the presence of higher concentrations of nitro compounds and alkalis. © VSP 2005.

Interdisciplinary approach to treat dyskeratosis congenita associated with severe aplastic anemia: A case report

This paper reports on a 4-year-old male who had dyskeratosis congenita and who acquired severe aplastic anemia. The patient developed hyperpigmentation of the face, neck and chest region, arms, shoulders and legs. In addition, he had dry skin, deformed fingernails and toenails, sparse hair and eyebrows and hyperkeratosis of the dorsum of the hands and feet. Laboratory and histological analysis revealed severe pancytopenia and dyserythropoiesis of red blood cells, hypocellularity of white blood cells and decreased megakaryocytes with dysplasia. The intraoral examination identified bleeding gums; petechiae of the palate, tongue and cheek mucosa; and an atrophic, smooth and shining dorsal surface of the tongue. There were deep carious lesions in the deciduous mandibular molars and maxillary anterior teeth; as well as mobility of mandibular left canine, which had bone loss. The treatment for oral lesions included diet changes, improved oral hygiene, and extraction of the deciduous teeth destroyed by caries.

Automated extraction of road network from medium-and high-resolution images

This paper presents an automatic methodology for road network extraction from medium-and high-resolution aerial images. It is based on two steps. In the first step, the road seeds (i.e., road segments) are extracted using a set of four road objects and another set of connection rules among road objects. Each road object is a local representation of an approximately straight road fragment and its construction is based on a combination of polygons describing all relevant image edges, according to some rules embodying road knowledge. Each road seed is composed by a sequence of connected road objects in which each sequence of this type can be geometrically structured as a chain of contiguous quadrilaterals. In the second step, two strategies for road completion are applied in order to generate the complete road network. The first strategy is based on two basic perceptual grouping rules, i.e., proximity and collinearity rules, which allow the sequential reconstruction of gaps between every pair of disconnected road segments. This strategy does not allow the reconstruction of road crossings, but it allows the extraction of road centerlines from the contiguous quadrilaterals representing connected road segments. The second strategy for road completion aims at reconstructing road crossings. Firstly, the road centerlines are used to find reference points for road crossings, which are their approximate positions. Then these points are used to extract polygons representing the contours of road crossings. This paper presents the proposed methodology and experimental results. © Pleiades Publishing, Inc. 2006.

Effects of tissucol™ and epsilon aminocaproic acid in the healing process following dental extraction in dehydrated rats

A histological study was conducted of the alveolar bone healing process following tooth extraction of dehydrated rats after the implantation of fibrin adhesive (TISSUCOL™) associated to previous irrigation of the wound with a 5% epsilon aminocaproic acid solution (EACA). Seventy two rats were used, divided into three groups receiving different treatments after the surgical procedure. In group I, the gingival mucosa was sutured after extraction of the right upper incisor. In groups II and III, chronic dehydration was produced by water deprivation for 9 days (3 days in the preoperative period and 6 days in the postoperative period). In the animals of Group II, after tooth extraction, the gingival mucosa was sutured in the same way as performed in group I. In group III, after extraction, the dental socket was irrigated with 5% EACA, followed by implantation of the fibrin adhesive (TISSUCOL™). The mucosa was sutured in the same way as performed in the other groups. At 3, 7, 15 and 21 postoperative days, the animals were sacrificed in number of 6 for each group. Specimens containing the dental socket were removed and fixed in 10% formalin and decalcified in an equal part formic acid and sodium citrate solution. After routine processing, the specimens were embedded in paraffin for microtomy. We obtained 6 μm semi-serial slices that were stained with hematoxylin and eosin for histological evaluation. The results showed that the water deprivation in the pre- and postoperative periods caused a delay in the alveolar bone healing process. The use of the fibrin adhesive (TISSUCOL™) produced an improvement in the fibrinolytic picture caused by dehydration.

Bone reformation and implant integration following maxillary sinus membrane elevation: An experimental study in primates

Background: Recent clinical studies have described maxillary sinus floor augmentation by simply elevating the maxillary sinus membrane without the use of adjunctive grafting materials. Purpose: This experimental study aimed at comparing the histologic outcomes of sinus membrane elevation and simultaneous placement of implants with and without adjunctive autogenous bone grafts. The purpose was also to investigate the role played by the implant surface in osseointegration under such circumstances. Materials and Methods: Four tufted capuchin primates had all upper premolars and the first molar extracted bilaterally. Four months later, the animals underwent maxillary sinus membrane elevation surgery using a replaceable bone window technique. The schneiderian membrane was kept elevated by insertion of two implants (turned and oxidized, Brånemark System®, Nobel Biocare AB, Göteborg, Sweden) in both sinuses. The right sinus was left with no additional treatment, whereas the left sinus was filled with autogenous bone graft. Implant stability was assessed through resonance frequency analysis (Osstell™, Integration Diagnostics AB, Göteborg, Sweden) at installation and at sacrifice. The pattern of bone formation in the experimental sites and related to the different implant surfaces was investigated using fluorochromes. The animals were sacrificed 6 months after the maxillary sinus floor augmentation procedure for histology and histomorphometry (bone-implant contact, bone area in threads, and bone area in rectangle). Results: The results showed no differences between membrane-elevated and grafted sites regarding implant stability, bone-implant contacts, and bone area within and outside implant threads. The oxidized implants exhibited improved integration compared with turned ones as higher values of bone-implant contact and bone area within threads were observed. Conclusions: The amount of augmented bone tissue in the maxillary sinus after sinus membrane elevation with or without adjunctive autogenous bone grafts does not differ after 6 months of healing. New bone is frequently deposited in contact with the schneiderian membrane in coagulum-alone sites, indicating the osteoinductive potential of the membrane. Oxidized implants show a stronger bone tissue response than turned implants in sinus floor augmentation procedures. © 2006 Blackwell Publishing, Inc.

Root trunk height as a risk factor for periodontal furcation involvement in maxillary first molars: an in vitro study.

The aim of this study was to correlate the root trunk height from the furcation openings on the buccal, mesial and distal surfaces to the cemento-enamel junction in upper first permanent molars in human beings with risk for periodontal disease progression. One hundred extracted maxillary first molars were used. Reference points and demarcations were determined from the entrance of the buccal (F1), mesial (F2) and distal (F3) furcations to the cemento-enamel junction in millimeters. The mean distances found were 3.50 mm, 4.44 mm and 4.26 mm for the buccal, mesial and distal furcations, respectively, in relation to the cemento-enamel junction. The statistical analyses were Student's t-test and Chi-square (X2). With periodontal disease progression, the buccal furcation presents a greater compromising risk due to its proximity to the cemento-enamel junction, while the mesial furcation is the most distant, comprising a lesser risk.

Measurement of sealant surface area by clinical/computerized analysis: 11-year results.

OBJECTIVE: To analyze the clinical behavior of 2 pit and fissure sealants through clinical/computerized evaluation. METHOD AND MATERIALS: Occlusal sealants were placed on maxillary and mandibular first and second premolars according to a split-mouth design. All premolars were sealed with either Concise (3M Espe) or Prisma Shield (Caulk/Dentsply) sealant agents. A hematoxylin-based staining solution was applied on the occlusal surface 7 days, 18 months, 36 months, and 11 years after occlusal sealing to allow checking of the sealant material on the surface. At each analysis time all occlusal surfaces were photographed, and the photographs corresponding to each time period were analyzed with SigmaScan 4.0 Software. The alterations of the sealed area of each sealant were analyzed with the software and recorded. Next, the measurements of the areas were tabulated and analyzed according to each period. Analysis of variance (ANOVA), with parts subdivided into time, and the t test, with a significance level of 5%, were used. RESULTS: The greatest sealed area was maintained by the sealant Concise. However, over the course of 11 years, all sealants began to show the same level of alteration in sealed area. CONCLUSION: The sealing materials showed alteration in sealed area over time, but they were efficient in controlling caries lesion formation on premolar pits and fissures.

Regional odontodysplasia: Case report

Regional odontodysplasia (RO) is a rare developmental anomaly involving both mesodermal and ectodermal dental components in a group of contiguous teeth. It affects the primary and permanent dentitions in the maxilla and mandible or both jaws. Generally it is localized in only one arch. The etiology of this dental anomaly is uncertain. Clinically, affected teeth have an abnormal morphology, are soft on probing and typically discolored, yellow or yellowish-brown. Radiographically, the affected teeth show a ghostlike appearance. This paper reports the case of a 5-year-old girl presenting this rare anomaly on the left side of the maxillary arch, which crossed the midline. The primary maxillary left teeth (except for the canine) and the primary maxillary right central incisor were missing due to previous extractions. The permanent teeth had a ghostlike appearance radiographically. The treatment performed was rehabilitation with temporary partial acrylic denture and periodic controls. In the future, the extraction of affected permanent teeth and rehabilitation with dental implants will be evaluated. The presentation of this case adds valuable information to pediatric dentists to review special clinical and radiographic features of RO, which will facilitate the diagnosis and treatment of patients with this condition.

Histological and histomorphometrical alterations of the periodontal ligament in gerbils submitted to teeth extraction

This study verified the effect of unilateral teeth extraction on the periodontal ligament in gerbils (Meriones unguiculatus). Ten adult male gerbils weighing about 50 g had induced occlusal alterations by upper left molar extractions while the other ten animals, only submitted to surgical stress, were considered as controls. The periodontal ligament was characterized by qualitative and quantitative analysis, histological description and histomorphometric quantification. Significant alterations were observed on the left side of the experimental group (P < 0.05), the hypofunctional region, when it was compared with the contralateral side and the corresponding region of the control group. Two months after occlusal alterations induced by unilateral teeth extraction, atrophic histological alterations and a decrease in the periodontal space on the ipsilateral side characterized the periodontal ligament. In this study it was possible to conclude that the gerbil can be used in experimental models attempting to correlate the periodontium's biological response to various mechanical stresses, as the periodontal ligament was shown to be highly sensitive to occlusal alterations. © 2008 The Authors.

Influence of local tetracycline on the microbiota of alveolar osteitis in rats

The aim of the present study was to evaluate the effects of local tetracycline on the occurrence of alveolar osteitis in rats, and on the microbiota associated to this infection. Forty Wistar rats were randomly assigned to 4 groups (n=10): I - the rats had the maxillary right incisor extracted and the alveolar wound did not receive any treatment; II - adrenaline and Ringer-PRAS were introduced into the alveolar wound; III - the alveolar wound was irrigated with sterile saline; and IV - the alveolar wound was irrigated with an aqueous solution of tetracycline. Microbial samples from the alveolar wounds were collected 2 days after surgery and inoculated on blood agar (with and without 8 μg/mL of tetracycline) and other selective media, and were incubated in either aerobiosis or anaerobiosis at 37°C, for 2 to 14 days. It was verified that tetracycline reduced the occurrence of alveolar osteitis in the rats and caused significant changes in the microbiota of the surgical sites, decreasing the number of anaerobes and increasing the participation of tetracycline-resistant and multi-resistant microorganisms.

Influence of storage period and effect of different brands of acrylic resin on the dimensional accuracy of the maxillary denture base

The aim of this study was to evaluate the dimensional changes of denture bases made from different resins after different storage periods. For this purpose, 25 sets of plaster models/resin bases were prepared using 4 acrylic resins submitted to two types of polymerization: 1- QC-20 submitted to polymerization by microwave energy; 2- QC-20 submitted to polymerization by water hot bath; 3- Vipi Cril submitted to polymerization by water hot bath; 4- Vipi Wave submitted to polymerization by microwave energy; and 5- Onda Cryl submitted to polymerization by microwave energy. After polymerization, the specimens were sectioned for accuracy readings using a comparison microscope. Readings were taken at 3 points: the crests of the right (A) and left (B) ridges, and the median region of the palate, in 4 different periods. The data obtained were submitted to two-way ANOVA and Tukey's test at 5% significance level. The greatest distortions were found in the posterior palatal region of the base (M), with statistically significant difference (p<0.05) for the studied resins. All acrylic resins presented dimensional changes and the storage period influenced these alterations.