Densitometric analysis of the autogenous demineralized dentin matrix on the dental socket wound healing process in humans

The aim of this study was to evaluate the effects of the autogenous demineralized dentin matrix (ADDM) on the third molar socket wound healing process in humans, using the guided bone regeneration technique and a polytetrafluoroethylene barrier (PTFE). Twenty-seven dental sockets were divided into three groups: dental socket (Control), dental socket with PTFE barrier (PTFE), and dental socket with ADDM slices associated to PTFE banier (ADDM + PTFE). The dental sockets were submitted to radiographic bone densitometry analysis and statistical analysis on the 15th, 30th, 60th and 90th days using analysis of variance (ANOVA) and Tukey's test (p ≤ 0.05). The radiographic analysis of the ADDM + PTFE group showed greater homogeneity of bone radiopacity than the Control group and the PTFE group, during all the observation times. The dentin matrix gradually disappeared from the dental socket during the course of the repair process, suggesting its resorption during the bone remodeling process. It was concluded that the radiographic bone density of the dental sockets treated with ADDM was similar to that of the surrounding normal bone on the 90th day. The ADDM was biocompatible with the bone tissue of the surgical wounds of human dental sockets. The radiographic analysis revealed that the repair process was discreetly faster in the ADDM + PTFE group than in the Control and PTFE groups, although the difference was not statistically significant. In addition, the radiographic image of the ADDM + PTFE group suggested that its bone architecture was better than that of the Control and PFTE groups.

Bone healing in critical-size defects treated with bioactive glass/calcium sulfate: A histologic and histometric study in rat calvaria

Objective: The purpose of this study was to analyze histologically the influence of bioactive glass (BG) with or without a calcium sulfate (CS) barrier on bone healing in surgically created critical-size defects (CSD) in rat calvaria. Material and methods: A CSD was made in each calvarium of 48 rats. They were divided into three groups: C (control): blood clot only; BG: defect filled with BG; and BG/CS: defect filled with BG covered by a CS barrier. Animals were euthanized at 4 or 12 weeks. Formation of new bone was evaluated histomorphometrically. Results: No defect completely regenerated with bone. BG particles were observed in Groups BG and BG/CS at both periods of analysis. The thickness throughout the healing area in Groups BG and BG/CS was similar to the original calvarium, while Group C presented a thin connective tissue in the center of the defect in both periods of analysis. At 4 weeks, Groups C and BG/CS presented significantly more bone formation than Group BG. No significant differences were found between Groups C and BG/CS. At 12 weeks, no significant differences in the amount of bone formation were observed among the three groups. When comparing 4 and 12 weeks, there was a significant increase in new bone formation within groups BG and BG/CS, but not C. Conclusion: BG particles, used with or without a CS barrier, maintained the volume and contour of the area grafted in CSD. However, they did not lead to a significant difference in bone formation when compared with control at 12 weeks post-operative. © 2007 Blackwell Munksgaard.

Homogenous demineralized dentin matrix for application in cranioplasty of rabbits with alloxan-induced diabetes: Histomorphometric analysis

Purpose: The aim of this work was to evaluate the bone-repair process after implantation of homogenous demineralized dentin matrix (HDDM) slices in surgical defects created in the parietal bones of rabbits with alloxan-induced diabetes. Materials and Methods: Forty-eight rabbits were selected and divided into 4 groups of 12 rabbits: the control group, diabetic rabbits (D), diabetic rabbits with a PTFE barrier (D-PTFE), and diabetic rabbits with a PTFE barrier and with slices of homogenous demineralized dentin matrix (D-PTFE+HDDM). The diabetic animals received a single dose of alloxan monohydrate (90 mg/kg) intravenously on the marginal ear vein, and their blood glucose was verified daily. The rabbits were sacrificed after 15, 30, 60, and 90 days. The histologic findings show both better bone structure and significantly greater bone density, as determined by histomorphometric analysis, for the D-PTFE + HDDM group than for the other 3 groups (P < .01). It was also observed that the mean bone density increased gradually from 15 to 90 days (except in the D-PTFE group). Conclusion: It was concluded that the HDDM was biocompatible with the bone repair of diabetic rabbits and that HDDM slices stimulated bone tissue formation. Facilitation of bone repair with HDDM could be useful in diabetic patients.

Polyethylene gel in the subcutaneous tissue of rats: Histopathologic and systemic evaluation

Purpose: To evaluate the histological and systemic response to subcutaneous injection of polyethylene gel in rats. Methods: Twenty-one white male rats were divided into 3 groups (G): G1 and G2 received subcutaneous polyethylene gel injection in the dorsal midline and were sacrificed at 30 and 60 postoperative days, respectively. G3 was not exposed to the polyethylene gel and was sacrificed after 60 days. Blood levels of lactate dehydrogenase (LDH), creatine kinase (CK), and alkaline phosphatase (ALP) were evaluated. The heart, kidney, liver, adrenal gland, injection site, and adjacent tissues were histologically examined. The results were submitted to statistical analysis. Results: There was no clinical evidence of extrusion, reduction of the injected volume, or abnormalities in the adjacent tissues. Blood levels of CK and LDH were normal and similar in all groups. ALP levels were significantly lower in G2 than in G1 and G3. The systemic organs were normal on histological examination in the 3 groups evaluated. Microscopically, the polyethylene gel was surrounded by a thin pseudocapsule formation and minimal inflammatory cell response, which decreased from G1 to G2. Conclusion: The subcutaneous injection of polyethylene gel in rats elicited minimal local inflammatory response and no systemic side effects. Copyright © 2008 Informa Healthcare USA, Inc.

Bone regeneration in cranioplasty and clinical complications in rabbits with alloxan-induced diabetes

This research evaluated the bone repair process in surgical defects created on the parietal bones of diabetic rabbits using the guided bone regeneration technique to observe the effects of alloxan in the induction of diabetes mellitus. Twenty-four adult rabbits were divided into three study groups: control (C), diabetic (D) and diabetic associated to polytetrafluoroethylene (PTFE) membrane (D-PTFE). For diabetes induction the animals received one dose of monohydrated alloxan (90 mg/kg) by intravenous administration in the auricular or femoral vein. In group D-PTFE the membrane covered both the floor and the surface of the bone defect. In groups D and C, the bone defect was filled up with blood clot. The specimens were fixed in 10% formol and prepared for histomorphometric analysis. The results showed that the 90 mg/kg dose of monohydrate alloxan was sufficient to promote diabetes mellitus when administered in the auricular vein. Bone regeneration was slower in the diabetic group when compared with the control and diabetic-PTFE groups, but there was no significant statistical difference between the two experimental groups (D and D-PTFE). The oral and general clinical complications among the diabetics were weight loss, polyuria, polyphagia and severe chronic gingivitis.

Studying the satisfaction of patients on the outcome of an aesthetic dermatological filler treatment

Background: Many factors contribute to extend productive life in the modern world. Competition makes people worry about physical appearance, mosftly in respect to facial and skin aging. This has motivated new developments in cosmetic dermatology and the need of evaluating patient satisfaction with the new proposed treatments. Poll questionnaire has been used for such evaluation, and the analysis of the electroencephalogram (EEG) mapping obtained while the patient answers the satisfaction questionnaire may render the results less subjective. Objectives: The purpose of this paper is to study the satisfaction of a group of 33 women (mean age, 44.years) treated with hyaluronic acid filling of nasolabial folding or lips, combining the EEG brain mapping and questionnaire techniques. Methods: At the third month of evaluation, two networked personal computers were used for the EEG recording and for presenting the patient with a questionnaire about her well-being feeling; self-evaluation of her face; her satisfaction with the results of the aesthetic treatment; how the family, friends, and people at work evaluated the result of the treatment; and her decision to repeat the treatment and to recommend it to friends and family. Results: Poll results showed that patients were feeling well and were satisfied with the results of the aesthetic treatment. Furthermore, the regression EEG mappings showed patients to be satisfied with their appearance and with the treatment involving similar brain areas. Conclusion: Patients decided to undergo the treatment because they were already considering it (54%) or because they were dissatisfied with their lips or nasolabial folding (52%). The fact that the treatment was free of charge solidified the decision. Patients consider themselves as good-looking and they wanted to preserve such a condition. © 2008 Wiley Periodicals, Inc.

Optical density of bone repair after implantation of homogenous demineralized dentin matrix in diabetic rabbits

This research evaluated the bone repair process after implantation of homogenous demineralized dentin matrix (HDDM) in surgical defects in the parietal bone of rabbits with alloxan-induced diabetes, using a polytetrafluorethylene (PTFe) barrier for guided bone regeneration. Thirty-six rabbits were used and divided into four groups: control (C, n = 12), diabetic (D, n = 12, left parietal bone), diabetic with PTFe (DPTFe, same 12 rabbits, right parietal bone), and diabetic with PTFe associated to HDDM (D-PTFe+HDDM, n = 12). Bone defects were created in the parietal bone of the rabbits and the experimental treatments were performed, where applicable. The rabbits were sacrificed after 15, 30, 60 and 90 days. The bone defects were examined radiographically and by optical density (ANOVA and Tukey test, p < .05). The radiographic findings showed that the D-PTFe+HDDM group presented greater radiopacity and better trabecular bone arrangement when compared to that of the C, D and D-PTFe groups. The statistical analysis showed significant differences in the optical density of the newly formed bone among the studied groups. It was possible to conclude that HDDM was biocompatible in diabetic rabbits.

Sistemas biodegradáveis contendo acetato de prednisolona para administração orbitária

Purpose: The present study aimed to evaluate an injectable extended-release formulation of prednisolone acetate (PA) for orbital administration. Methods: Microspheres (MEs) of poly-ε-caprolactone (PCL) containing PA were developed by the method of solvent evaporation. The MEs obtained were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), encapsulation efficiency and in vitro release profile. The in vivo release profile was evaluated in rabbits after periocular injection of an aqueous suspension of MEs. The local biocompatibility of the system was verified by histopathologic analysis of the deployment region. Results: After MEs preparation, morphological analysis by SEM showed the feasibility of the employed method. The content of PA encapsulated was 43 ± 7% and can be considered as satisfactory. The system characterization by DSC technique, in addition to confirm the system stability, did not indicate the existence of interaction between the drug and the polymer. The in vitro release study showed the prolonged-release features of the developed system. Preliminary in vivo study showed the absence of local toxicity and confirmed the prolonged release profile of PA from MEs, suggesting the viability of the developed system for the treatment of orbital inflammatory diseases. Conclusion: The results obtained in this work are relevant and accredit the system developed as a possible alternative to the treatment of inflammatory orbitopathy.

Characterization and in vitro cytocompatibility of an acid-etched titanium surface

The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H 2SO 4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.

Effect of weathering and thickness on roughness of acrylic resin and ocular button

Purpose: The aim of this study was to evaluate the roughness of colorless ocular button and four brands of colorless acrylic resins designed to fabricate ocular prosthesis as a function of weathering (1008 h) and different thickness (1 and 3.5 mm). Materials and methods: One-hundred-and-twenty specimens were fabricated and distributed in 12 groups. The analysis was carried out by means of digital roughness meter. Results: Data were analyzed statistically by ANOVA and Tukey test at 1% significance. The results showed that there was no statistically significant difference after the weathering period. Both the Vipi Cril acrylic resin with 3.5 mm in thickness and ocular button with 1 mm in thickness presented the lowest roughness values (0.12. Ra). Conclusion: The roughness of the acrylic resins and the ocular button was not affect by the weathering of 1008 h. However, the thickness of the specimens proved to have a major influence on roughness property. © 2010.

Osteoconductivity of modified fluorcanasite glass-ceramics for bone tissue augmentation and repair

Modified fluorcanasite glasses were fabricated by either altering the molar ratios of Na 2O and CaO or by adding P 2O 5 to the parent stoichiometric glass compositions. Glasses were converted to glass-ceramics by a controlled two-stage heat treatment process. Rods (2 mm x 4 mm) were produced using the conventional lost-wax casting technique. Osteoconductive 45S5 bioglass was used as a reference material. Biocompatibility and osteoconductivity were investigated by implantation into healing defects (2 mm) in the midshaft of rabbit femora. Tissue response was investigated using conventional histology and scanning electron microscopy. Histological and histomorphometric evaluation of specimens after 12 weeks implantation showed significantly more bone contact with the surface of 45S5 bioglass implants when compared with other test materials. When the bone contact for each material was compared between experimental time points, the Glass-Ceramic 2 (CaO rich) group showed significant difference (p = 0.027) at 4 weeks, but no direct contact at 12 weeks. Histology and backscattered electron photomicrographs showed that modified fluorcanasite glass-ceramic implants had greater osteoconductivity than the parent stoichiometric composition. Of the new materials, fluorcanasite glass-ceramic implants modified by the addition of P 2O 5 showed the greatest stimulation of new mineralized bone tissue formation adjacent to the implants after 4 and 12 weeks implantation. © 2010 Wiley Periodicals, Inc.

Repair of bone cavities in dog's mandible filled with inorganic bovine bone and bioactive glass associated with platelet rich plasma

The aim of this study was to evaluate the effect of platelet rich plasma (PRP) associated to bovine inorganic bone (Bio-Oss®; Geistlich) or bioactive glass (Bio-Gran®; Orthovita, Implant Innovations) on bone healing. Bone cavities were prepared in both sides of the mandible of 4 adult male dogs. The cavities were divided into 4 groups according to the filling material as follows: control, PRP, PRP/Bio-Oss, PRP/Bio-Gran. The animals were sacrificed after 120 days and histological and histomorphometrical analysis was performed. The control group showed 80.6% of bone formation in the longitudinal sections at 6 mm depth and 83.7% at 13 mm depth. The transverse sections displayed 74.2% at both 6 and 13 mm depths. The PRP group showed 21.1% of bone formation in the longitudinal sections at 6 mm depth, and 23.1% at 13 mm depth. The transverse sections presented 28.98% of bone formation at 6 mm depth and 41.2% at 13 mm depth. The PRP/Bio-Gran group showed 25.1% of bone formation in the longitudinal sections at 6 mm depth and 30.4% at 13 mm depth. In the transverse sections, the bone formation was 43.0% at 6 mm depth and 39.7% at 13 mm depth. The PRP/Bio-Oss group showed 35.5% of bone formation in the longitudinal sections at 6 mm depth and 42% at 13 mm depth. In the transversal sections, the bone formation was 26.8% and 31.2% at the depths of 6 and 13 mm, respectively. PRP alone or associated with bovine inorganic bone or bioglass had no significant effect in bone healing.

Evaluation of tissue reaction, cell viability and cytokine production induced by Sealapex Plus

The aim of this study was to investigate the effects of mineral trioxide aggregate (MTA), Sealapex, and a combination of Sealapex and MTA (Sealapex Plus) on the reaction of subcutaneous connective tissue of rats, and on cell viability and cytokine production in mouse fibroblasts. The tissue reaction was carried out with dentin tubes containing the materials implanted in the dorsal connective tissue of rats. The histological analysis was performed after 7 and 30 days. Millipore culture plate inserts with polyethylene tubes filled with materials were placed into 24-well cell culture plates with mouse fibroblasts to evaluate the cell viability by MTT assay. ELISA assays were also performed after 24 h of exposure of the mouse fibroblasts to set material disks. Histopathologic examination showed Von Kossa-positive granules that were birefringent to polarized light for all the studied materials at the tube openings. No material inhibited the cell viability in the in vitro test. It was detected IL-6 production in all root-end filling materials. MTA and Sealapex Plus induced a slight raise of mean levels of IL-1β. The results suggest that Sealapex Plus is biocompatible and stimulates the mineralization of the tissue.

Effect of disinfection and accelerated ageing on dimensional stability and detail reproduction of a facial silicone with nanoparticles

The aim of the present study was to evaluate the effect of disinfection and accelerated ageing on the dimensional stability and detail reproduction of a facial silicone with different types of nanoparticle. A total of 60 specimens were fabricated with Silastic MDX 4-4210 silicone and they were divided into three groups: colourless and pigmented with nanoparticles (make-up powder and ceramic powder). Half of the specimens of each group were disinfected with Efferdent tablets and half with neutral soap for 60 days. Afterwards, all specimens were subjected to accelerated ageing. Both dimensional stability and detail reproduction tests were performed after specimen fabrication (initial period), after chemical disinfection, and after accelerated ageing periods (252, 504 and 1008 hours). The dimensional stability test was conducted using AutoCAD software, while detail reproduction was analysed using a stereoscope magnifying glass. Dimensional stability values were statistically evaluated by analysis of variance (ANOVA) followed by Tukey's test (p < 0.01). Detail reproduction results were compared using a score. Chemical disinfection and also accelerated ageing affected the dimensional stability of the facial silicone with statistically significant results. The silicone's detail reproduction was not affected by these two factors regardless of nanoparticle type, disinfection and accelerated ageing. © 2012 Informa UK, Ltd.

Biocompatibility analysis of Bioglass® 45S5 and Biosilicate® implants in the rabbit eviscerated socket

Purpose: Bioactive glass and bioactive glass-ceramic cone implants were placed in the rabbit eviscerated socket to assess their biocompatibility. Methods: Fifty-one Norfolk albino rabbits underwent evisceration of the right eye followed by implantation of cones made from Bioglass® 45S5 (control group) and two types of bioactive glass-ceramic (Biosilicate®), a single- and a two-phase bioactive glass-ceramic implants into the scleral cavity. Postoperative reactions, animal behavior and socket conditions were monitored daily. Clinical exam, biochemical evaluations, and orbit computed tomographic scan were done at 7, 90, and 180 days post-procedure. After that, the animals were euthanized, and the orbital content was removed and prepared to light microscopy with morphometric evaluation and scanning electron microscopy examination. Statistical analysis was done by parametric and non-parametric analysis of variance, complemented by Dunn's and Tukey's tests (p<0.05). Results: All animals did not develop systemic toxicity throughout the experimental period and also did not have orbit infection, implant migration or extrusion. Morphological analysis demonstrated pseudocapsule around all implants. Bioglass® and single-phase Biosilicate® implants induced less inflammation and pseudocapsule formation than two-phase Biosilicate® cones. Seven days post-procedure, the inflammatory reaction was intense and gradually decreased throughout the experiment. Tissue reaction was least intense in animals receiving Bioglass® implants. Conclusions: We observe discrete differences among the studied materials, with best responses obtained with use of Bioglass® 45S5 and single-phase Biosilicate®. The authors agree these implants might be useful in the management of the anophthalmic socket. © 2012 Informa Healthcare USA, Inc.