Radiographic and histomorphometric analysis of bone healing using autogenous graft associated with platelet-rich plasma obtained by 2 different methods

The aim of this study was to conduct radiographic and histomorphometric analysis of bone healing in the calvaria of rabbits, using an autogenous graft associated with PRP obtained by 2 different methods. Thirty rabbits were divided into control and experimental groups. Lesions were produced in the calvaria and filled with autogenous graft ( control) or autogenous graft and PRP obtained by the Anitua or modified Sonnleitner methods. The animals were humanely killed 15 days after surgery and the calvarias were radiographed. The radiographs were digitized to assess the radiographic density. By histologic images of the lesion, the bone matrix was quantified. There were no significant differences in the radiographic density and the bone matrix area between the groups. The association of PRP with autogenous bone did not improve the healing process, irrespective of the method used early during healing.

Mandibular cortical bone evaluation on cone beam computed tomography images of patients with bisphosphonate-related osteonecrosis of the jaw

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Paracoccidioidomicose: estudo radiológico e pulmonar de 58 casos

Spirometric and haemogasimetric tests were performed in 52 patients with unifocal and multifocal progressive Paracoccidioidomycosis pulmonary diseases, in 5 patients with juvenile and 1 female internal genital forms. The age ranged from 20 to 74 years old and the duration of disease from 3 to 25 years. Dyspnea, cough, tegumentary and lymphatic manifestations were the most predominant signs observed. Fourteen of them was developed Cor pulmonale. Impaired renal function was recorded in 19 patients, cardiac symptoms were described in 7 and hyporeactor adrenal activity was showed in 13 patients. Radiological studies demonstrated mild in 16, moderate in 24 and severe pulmonary lesions types in 18 patients. The pulmonary function revealed: normal spyrographic findings in 17, pure obstructive type in 32 and mixed form in 9 of them. Hyperventilation was described in 54 individuals and all of them showed an increasing of the alveolo-arterial difference. PaO2 less than 80 mm/Hg observed in 36 of them. Statistical analysis demonstrated significative association between clinical evolution and radiological interpretation. Similar data were obtained in radiology evaluations, clinical evolutive studies and pulmonary functions described in these patients. The granulomatous reaction due to Paracoccidioidomycosis, in heavy smokers patients, gave origin to the alterations in small airways predisposing the interalveolar dissemination an impaired alveolo-arterial diffusion.

Niobium filtration of conventional and high-frequency x-ray generator beams for intraoral radiography. Effects on absorbed doses, image density and contrast, and photon spectra

We have studied the effects of niobium beam filtration on absorbed doses, on image density and contrast, and on photon spectra with conventional and high-frequency dental x-ray generators. Added niobium reduced entry and superficial absorbed doses in periapical radiography by 9% to 40% with film and digital image receptors, decreased the radiation necessary to produce a given image density on E-speed film and reduced image contrast on D- and E-speed films. As shown by increased half-value layers for aluminum, titanium, and copper and by pulse-height analyses of beam spectra, niobium increased average beam energy by 6% to 19%. Despite the benefits of adding niobium on patient dose reduction and on narrowing the beams' energy spectra, the beam can be overhardened. Adding niobium, therefore, strikes the best balance between radiation dose reduction and beam attenuation, with its risks of increased exposure times, motion blur, and diminished image contrast, when it is used at modest thicknesses (30 μm) and at lower kVp (70) settings. © 1995 Mosby-Year Book, Inc.

Dosimetry and cost of imaging osseointegrated implants with film-based and computed tomography

Thermoluminescent dosimeters were used to measure radiation doses at craniofacial sites in a tissue-equivalent phantom during film-based multidirectional tomography with the Tomax Ultrascan (Incubation Industries, Ivyland, Pa.) and during computed tomography with the Elscint Excel 2400 (Elscint Corp., Tel Aviv, Israel). Mean absorbed doses for presurgical mandibular and maxillary canine and molar implant assessments were converted to equivalent doses, which were then multipied by published weighting factors and summed to give effective doses. The computed tomgraphy device consistently delivered higher doses than the Tomax Ultrascan to all anatomic locations; the differences were most pronounced when only one or two implant sites were evaluated. The reasons for the dose disparities are considered both anatomically and procedurally. A survey of examination cost revealed film-based multidirectional tomography to be less expensive than computed tomography.

Release of formaldehyde by 4 endodontic sealers

Objective. The purpose of this study was to evaluate the release of formaldehyde by some root canal filling materials. Study design. Two older endodontic sealers, AH 26 and Endomethasone, and 2 recently available sealers, AH Plus and Top Seal, were analyzed. Infrared and electronic spectroscopy were used to determine formaldehyde content after set of the materials. Results. Analysis showed that the AH 26 and Endomethasone sealers released formaldehyde. Although the AH Plus and Top Seal sealers have similar chemical composition, they released formaldehyde in a minimal concentration. Conclusions. The AH 26 and Endomethasone sealers released formaldehyde after setting; however, a minimum release was observed for the AH Plus and Top Seal sealers. Copyright © 1999 by Mosby, Inc.

Collateral cartilage ossification of the distal phalanx in the Brazilian Jumper horse

Collateral cartilage ossification of the distal phalanx in the Brazilian Jumper horse is a common finding. The objective of this study was to evaluate the prevalence and the degree of ossification of the collateral cartilages of the distal phalanx in Brazilian Jumper horses. In an analysis of 652 collateral cartilages from the front feet of 163 horses, 93% of these cartilages had collateral cartilage ossification (P < 0.005), and 7% of these cartilages did not have any type of ossification. In ossified cartilages, 86.4% had ossification beginning from the base, and 6.6% had a separate center of ossification.

Early healing pattern of autogenous bone grafts with and without e-PTFE membranes: A histomorphometric study in rats

Objective. The aim of this study was to perform quantitative and qualitative analyses of the initial repair pattern of an autogenous bone block graft when covered or not with e-PTFE membranes. Study design. Sixty male Wistar rats received a bone graft plus an e-PTFE membrane (MB) or just the graft (B). A block graft was harvested from the animal's calvarium and was laid and stabilized on the external cortical area near the angle of the mandible. Descriptive histology and histomorphometric analyses were carried out and the data were analyzed statistically by ANOVA and the Tukey test, with the level of significance set at 5%. Results. The results for group B showed that there was bone loss during the healing period (B0 = 1.38, B45 = 1.05, F = 7.91 > F C = 3.02), that is, the initial volume of the graft decreased in time. Bone tissue loss was about 24%. In contrast, the MB group showed bone tissue gain along the observation period (MB0 = 1.54, MB45 = 2.40, F = 7.91 > FC = 3.02), meaning that the total volume of newly formed bone was greater than the original graft area. Bone tissue gain was approximately 55%. MB showed significantly greater bone gain when compared to B (B45 = 1.05, MB45 = 2.40, F = 39.86 > FC = 1.90). These significant differences between B and MB could already be observed after 21 days. Conclusions. The bone block graft underwent resorption at an early healing stage, while additional new bone formation was observed when the bone graft was covered with an e-PTFE membrane. © 2005 Mosby, Inc. All rights reserved.

Sleep bruxism: Clinical aspects and characteristics in patients with and without chronic orofacial pain

Objective. Evaluation of long-standing sleep bruxism (SB) patients. Study Design. Descriptive study. Results. One hundred subjects with SB (80 women and 20 men, mean age: 36.1±11.3 years) were evaluated according to the RDC/TMD and a pain questionnaire (EDOF-HC). The patients were divided into 2 groups: Group A-without (30.0%) and Group B-with orofacial pain (70.0%). AM stiffness: 36.4% in Group A and 88.6% in Group B; mean pain duration: 6.92 years; mean intensity of pain: 4.33 (VAS); quality of pain: tightness/pressure (84,3%); 95.7% of Group B had myofascial pain. Depression and somatization levels were different between the groups (p = 0.001). Higher frequency of depression was found with body pain or presence of comorbidities. Conclusion. The data presented in this study showed statistical differences between long-standing bruxism without and with chronic facial pain; the two questionnaires allowed interaction between the chief complaint and the clinical findings; depression levels increased with pain in several regions of the body. © 2006 Elsevier Inc. All rights reserved.

Articaine and mepivacaine efficacy in postoperative analgesia for lower third molar removal: a double-blind, randomized, crossover study

Objective: Comparison of the clinical efficacy of 4% articaine in relation to 2% mepivacaine, both with 1:100,000 epinephrine, in the prevention of postoperative pain after lower third molar removal. Study design: Twenty patients underwent removal of bilateral lower third molars under local anesthesia (articaine or mepivacaine) in 2 separate appointments, in a double-blind, randomized, and crossed manner. Objective and subjective parameters were recorded for paired comparison of postoperative courses. Results: Duration of analgesia provided by articaine and mepivacaine was 198.00 ± 25.86, and 125.40 ± 13.96 min, respectively (P = .02), whereas the duration of anesthesia was 273.80 ± 15.94 and 216.85 ± 20.15 min, respectively (P = .06). Both solutions exerted no important effects upon arterial pressure, heart rate, or oxygen saturation (P > .05). Conclusions: Articaine provides a longer period of analgesic effect and a tendency for a longer period of anesthesia as compared to mepivacaine. The presence of a vasoconstrictor agent in local anesthetic solutions does not seem to influence hemodynamic parameters during lower third molar removal in healthy subjects. © 2006 Mosby, Inc. All rights reserved.

Antimicrobial endodontic compounds do not modulate alkylation-induced genotoxicity and oxidative stress in vitro

Objective: To investigate if formocresol, paramonochlorophenol, or calcium hydroxide modulate the genotoxic effects induced by the oxidatively damaging agent hydrogen peroxide (H 2O 2) or the alkylating agent methyl methanesulfonate (MMS) in vitro by using single cell gel (comet) assay. Study design: Chinese hamster ovary (CHO) cells in culture were exposed directly to formocresol, paramonochlorophenol, or calcium hydroxide (adjusted to 100 μg/mL) for 1 hour at 37°C. Subsequently the cultures were incubated with increasing concentrations (0-10 μmol/L) of MMS in phosphate-buffered solution (PBS) for 15 minutes at 37°C or of H 2O 2 at increasing concentrations (0-100 μmol/L) in distilled water for 5 minutes on ice. The negative control cells were treated with PBS for 1 hour at 37°C. The parameter from the comet assay (tail moment) was assessed by the Kruskal-Wallis nonparametric test followed by a post hoc analysis (Dunn test). Results: Clear concentration-related effects were observed for the genotoxin-exposed CHO cells. Increase of MMS-induced DNA damage was not significantly altered by the presence of the compounds tested. Similarly, no significant changes were observed when hydrogen peroxide was used with the endodontic compounds evaluated. Conclusion: Formocresol, paramonochlorophenol, and calcium hydroxide are not able to modulate alkylation-induced genotoxicity or oxidative DNA damage as depicted by the single cell gel (comet) assay. © 2006 Mosby, Inc. All rights reserved.