Ressonância magnética nos desarranjos internos da ATM: sensibilidade e especificidade

OBJETIVO: esta revisão de literatura visa avaliar, através de literatura específica, a sensibilidade e especificidade do exame de ressonância magnética (RM) para o diagnóstico dos desarranjos internos da articulação temporomandibular (ATM). METODOLOGIA: tanto artigos que utilizaram ATM de cadáveres para comparar achados anatômicos aos achados de ressonância magnética (RM), como artigos que compararam achados clínicos com achados de RM foram utilizados. Através dos achados desses artigos, as propriedades de sensibilidade e especificidade da RM para o diagnóstico de desarranjos internos da ATM foram calculadas. Com isso, a confiabilidade e a aplicabilidade do exame de RM no diagnóstico dos desarranjos internos da ATM foram discutidas. RESULTADOS: encontrou-se sensibilidade de 90% e especificidade de 88% da RM para desarranjos internos da ATM. CONCLUSÃO: o exame de RM de ATM possui ótima sensibilidade e especificidade para o diagnóstico dos desarranjos internos da ATM. Porém, tal exame deve ser solicitado com cautela, apenas nos casos onde a imagem seja indispensável para o plano de tratamento.

Effects of light-curing time on the cytotoxicity of a restorative composite resin on odontoblast-like cells

This in vitro study evaluated the cytotoxicity of an experimental restorative composite resin subjected to different light-curing regimens. METHODS: Forty round-shaped specimens were prepared and randomly assigned to four experimental groups (n=10), as follows: in Group 1, no light-curing; in Groups 2, 3 and 4, the composite resin specimens were light-cured for 20, 40 or 60 s, respectively. In Group 5, filter paper discs soaked in 5 µL PBS were used as negative controls. The resin specimens and paper discs were placed in wells of 24-well plates in which the odontoblast-like cells MDPC-23 (30,000 cells/cm²) were plated and incubated in a humidified incubator with 5% CO2 and 95% air at 37ºC for 72 h. The cytotoxicity was evaluated by the cell metabolism (MTT assay) and cell morphology (SEM). The data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (p<0.05). RESULTS: In G1, cell metabolism decreased by 86.2%, indicating a severe cytotoxicity of the non-light-cured composite resin. On the other hand, cell metabolism decreased by only 13.3% and 13.5% in G2 and G3, respectively. No cytotoxic effects were observed in G4 and G5. In G1, only a few round-shaped cells with short processes on their cytoplasmic membrane were observed. In the other experimental groups as well as in control group, a number of spindle-shaped cells with long cytoplasmic processes were found. CONCLUSION: Regardless of the photoactivation time used in the present investigation, the experimental composite resin presented mild to no toxic effects to the odontoblast-like MDPC-23 cells. However, intense cytotoxic effects occurred when no light-curing was performed.

Acessibilidade em ambiente universitário: identificação de barreiras arquitetônicas no campus da USP de Bauru

A acessibilidade é um direito do cidadão assegurado por lei para que portadores de deficiência tenham a possibilidade de usufruir de recursos e ações no âmbito social. Barreiras arquitetônicas interferem na vida destes podendo deixá-los a parte da convivência e vida social. Os objetivos deste estudo foram: identificar, descrever e mapear barreiras físicas no Campus da Universidade de São Paulo de Bauru e apresentar as intervenções realizadas, durante o período de outubro de 2001 a dezembro de 2005. O estudo foi descritivo-quantitativo, no qual a coleta de dados centrou-se na análise das condições arquitetônicas das três unidades que compõe este campus, observada as normativas da Associação Brasileira de Normas técnicas e realizada intervenções. Foram identificados: 72 pontos de guias não rebaixadas, 21 pontos de acessos com diferenças de níveis sem rampas; 220m² de escadas/rampas sem corrimãos; 658m² de escadas/rampas com corrimãos em discordância com as normas vigentes; 03 rampas com inclinações superiores às determinadas nas normas técnicas; 10 banheiros parcialmente adaptados para deficientes; 02 vagas de estacionamento parcialmente adaptadas e 02 elevadores existentes. Foram executados, em 19 pontos, rebaixamentos de guias, somando 115 m², com linhas de piso tátil, pintados; 8 rampas; 14 pontos de escadas e rampas externas instaladas com corrimãos e guarda-corpos, 5 vagas exclusivas no estacionamento; instalado 2 centrais de atendimento telefônico para surdo e adquiridas 3 cadeira de rodas. As intervenções realizadas contribuíram para melhorar a acessibilidade de portadores de deficiência no campus favorecendo a utilização dos recursos existentes neste espaço público.

Angioleiomioma de cavidade nasal: relato de um caso e revisão de literatura

Leiomioma de cavidade nasal e seios paranasais é raro. Ele constitui menos de 1% de todos os leiomiomas do corpo humano. Isto se deve à escassez de células musculares no nariz. Estas neoplasias podem ser classificadas em três grupos: leiomioma, angiomioma e leiomioma epitelióide. Somente 15 casos de angiomioma foram encontrados na literatura. O tratamento de escolha é a excisão cirúrgica. Um novo caso e a revisão da literatura são apresentados.

Effect of biofunctionalized implant surface on osseointegration: a histomorphometric study in dogs

Among the different properties that influence bone apposition around implants, the chemical or biochemical composition of implant surface may interfere on its acceptance by the surrounding bone. The aim of this study was to investigate if a biofunctionalization of implant surface influences the bone apposition in a dog model and to compare it with other surfaces, such as a microstructured created by the grit-blasting/acid-etching process. Eight young adult male mongrel dogs had the bilateral mandibular premolars extracted and each one received 6 implants after 12 weeks, totaling 48 implants in the experiment. Four groups of implants were formed with the same microrough topography with or without some kind of biofunctionalization treatment. After histomorphometric analysis, it was observed that the modified microstructured surface with a "low concentration of the bioactive peptide" provided a higher adjacent bone density (54.6%) when compared to the other groups (microstructured + HA coating = 46.0%, microstructured only = 45.3% and microstructured + "high concentration of the bioactive peptide" = 40.7%), but this difference was not statistically significant. In conclusion, biofunctionalization of the implant surface might interfere in the bone apposition around implants, especially in terms of bone density. Different concentrations of bioactive peptide lead to different results.

Inflammation markers in healthy and periodontitis patients: a preliminary data screening

Advances in diagnostic research are moving towards methods whereby the periodontal risk can be identified and quantified by objective measures using biomarkers. Patients with periodontitis may have elevated circulating levels of specific inflammatory markers that can be correlated to the severity of the disease. The purpose of this study was to evaluate whether differences in the serum levels of inflammatory biomarkers are differentially expressed in healthy and periodontitis patients. Twenty-five patients (8 healthy patients and 17 chronic periodontitis patients) were enrolled in the study. A 15 mL blood sample was used for identification of the inflammatory markers, with a human inflammatory flow cytometry multiplex assay. Among 24 assessed cytokines, only 3 (RANTES, MIG and Eotaxin) were statistically different between groups (p<0.05). In conclusion, some of the selected markers of inflammation are differentially expressed in healthy and periodontitis patients. Cytokine profile analysis may be further explored to distinguish the periodontitis patients from the ones free of disease and also to be used as a measure of risk. The present data, however, are limited and larger sample size studies are required to validate the findings of the specific biomarkers.

Effects of a novel calcium aluminate cement on the early events of the progression of osteogenic cell cultures

The present study evaluated the progression of osteogenic cell cultures exposed to a novel calcium aluminate cement (CAC+) in comparison with the gold standard mineral trioxide aggregate (MTA). Cells were enzimatically isolated from newborn rat calvarial bone, plated on glass coverslips containing either CAC+ or a control MTA samples in the center, and grown under standard osteogenic conditions. Over the 10-day culture period, roundening of sample edges was clearly noticed only for MTA group. Although both cements supported osteogenic cell adhesion, spreading, and proliferation, CAC+-exposed cultures showed significantly higher values in terms of total cell number at days 3 and 7, and total protein content and alkaline phosphatase activity at day 10. The present in vitro results indicate that the exposure to CAC+ supports a higher differentiation of osteogenic cells compared with the ones exposed to MTA. Further experimental studies should consider CAC+ as a potential alternative to MTA when the repair of mineralized tissues is one of the desired outcomes in endodontic therapy.

Bone response to biosilicates® with different crystal phases

The aim of this study was to investigate the histological and histomorphometrical bone response to three Biosilicates with different crystal phases comparing them to Bioglass®45S5 implants used as control. Ceramic glass Biosilicate and Bioglass®45S5 implants were bilaterally inserted in rabbit femurs and harvested after 8 and 12 weeks. Histological examination did not revealed persistent inflammation or foreign body reaction at implantation sites. Bone and a layer of soft tissue were observed in close contact with the implant surfaces in the medullary canal. The connective tissue presented few elongated cells and collagen fibers located parallel to implant surface. Cortical portion after 8 weeks was the only area that demonstrated significant difference between all tested materials, with Biosilicate 1F and Biosilicate 2F presenting higher bone formation than Bioglass®45S5 and Biosilicate® vitreo (p=0.02). All other areas and periods were statistically non-significant (p>0.05). In conclusion, all tested materials were considered biocompatible, demonstrating surface bone formation and a satisfactory behavior at biological environment.

Orbital abscess after facial trauma

This paper reports a rare case of acute severe orbital abscess manifested 2 days after a facial trauma without bone fracture in a 20-year-old Afro-American female. The symptoms worsened within the 24 h prior to hospital admission resulting in visual disturbances such as diplopia and photophobia. The clinical findings at the first consultation included fever, periorbital swelling and redness, ptosis, proptosis and limitation of ocular movements upwards, downwards, to the right and to the left. Computed tomography scan showed proptosis with considerable soft tissue swelling on the left side and no fracture was evidenced in the facial skeleton, including the zygomatic-orbital complex. After hospital admission and antibiotic therapy intravenously the patient was conducted to the operation room and submitted to incision and drainage under general anesthesia. The orbit was approached thorough both eyelids and the maxillary sinus was reached only through the Caldwell-Luc approach. The postoperative period was uneventful and the rapid improvement of symptoms was remarkable. Visual acuity and ocular motility returned to the normal ranges within 2 days after the surgical intervention. After 12 postoperative days, the patient presented with significative improvement in the ptosis and proptosis, and acceptable scars.

Antibacterial activity of root canal filling materials for primary teeth: zinc oxide and eugenol cement, Calen paste thickened with zinc oxide, Sealapex and EndoREZ

This study evaluated in vitro the antibacterial activity of 4 root canal filling materials for primary teeth - zinc oxide and eugenol cement (ZOE), Calen paste thickened with zinc oxide (Calen/ZO), Sealapex sealer and EndoREZ sealer - against 5 bacterial strains commonly found in endodontic infections (Kocuria rhizophila, Enterococcus faecalis, Streptococcus mutans, Escherichia coli and Staphylococcus aureus) using the agar diffusion test (agar-well technique). Calen paste, 1% chlorhexidine digluconate (CHX) and distilled water served as controls. Seven wells per dish were made at equidistant points and immediately filled with the test and control materials. After incubation of the plates at 37oC for 24 h, the diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a digital caliper under reflected light. Data were analyzed statistically by analysis of variance and Tukey's post-hoc test (?=0.05). There were statistically significant differences (p<0.0001) among the zones of bacterial growth inhibition produced by the different materials against all target microorganisms. K. rhizophila was inhibited more effectively (p<0.05) by ZOE, while Calen/ZO had its highest antibacterial activity against E. faecalis (p<0.05). S. mutans was inhibited by Calen/ZO, Sealapex and ZOE in the same intensity (p>0.05). E. coli was inhibited more effectively (p<0.05) by ZOE, followed by Calen/ZO and Sealapex. Calen/ZO and ZOE were equally effective (p>0.05) against S. aureus, while Sealapex had the lowest antibacterial efficacy (p<0.05) against this microorganism. EndoREZ presented antibacterial activity only against K. rhizophila and S. aureus. The Calen paste and Calen/ZO produced larger zones of inhibition than 1% CHX when the marker microorganism was E faecalis. In conclusion, the in vitro antibacterial activity of the 4 root canal filling materials for primary teeth against bacterial strains commonly found in endodontic infections can be presented in a decreasing order of efficacy as follows: ZOE>Calen/ZO>Sealapex>EndoREZ.

Abrasion wear resistance of different artificial teeth opposed to metal and composite antagonists

One of the most important properties of artificial teeth is the abrasion wear resistance, which is determinant in the maintenance of the rehabilitation's occlusal pattern. OBJECTIVES: This in vitro study aims to evaluate the abrasion wear resistance of 7 brands of artificial teeth opposed to two types of antagonists. MATERIAL AND METHODS: Seven groups were prepared with 12 specimens each (BIOLUX & BL, TRILUX & TR, BLUE DENT & BD, BIOCLER & BC, POSTARIS & PO, ORTHOSIT & OR, GNATHOSTAR & GN), opposed to metallic (M & nickel-chromium alloy), and to composite antagonists (C & Solidex indirect composite). A mechanical loading device was used (240 cycles/min, 4 Hz speed, 10 mm antagonist course). Initial and final contours of each specimen were registered with aid of a profile projector (20x magnification). The linear difference between the two profiles was measured and the registered values were subjected to ANOVA and Tukey's test. RESULTS: Regarding the antagonists, only OR (M = 10.45 ± 1.42 µm and C = 2.77 ± 0.69 µm) and BC (M = 6.70 ± 1.37 µm and C = 4.48 ± 0.80 µm) presented statistically significant differences (p < 0.05). Best results were obtained with PO (C = 2.33 ± 0.91 µm and M = 1.78 ± 0.42 µm), followed by BL (C = 3.70 ± 1.32 µm and M = 3.70 ± 0.61 µm), statistically similar for both antagonists (p>0.05). Greater result variance was obtained with OR, which presented the worse results opposed to Ni-Cr (10.45 ± 1.42 µm), and results similar to the best ones against composite (2.77 ± 0.69 µm). CONCLUSIONS: Within the limitations of this study, it may be concluded that the antagonist material is a factor of major importance to be considered in the choice of the artificial teeth to be used in the prosthesis.

Metronidazole-containing gel for the treatment of periodontitis: an in vivo evaluation

The aim of this investigation was to monitor metronidazole concentrations in the gingival crevicular fluid (GCF) collected from periodontal pockets of dogs after treatment with an experimental 15% metronidazole gel. Five dogs had periodontitis induced by cotton ligatures placed subgingivally and maintained for a 30-day period. After the induction period, only pockets with 4 mm or deeper received the gel. Each pocket was filled up to the gingival margin by means of a syringe with a blunt-end needle. GCF was collected in paper strips and quantified in an electronic device before and after 15 minutes, 1 h, 6 h, 24 h and 48 h of gel administration. The GCF samples were assayed for metronidazole content by means of a high performance liquid chromatography method. Concentrations of metronidazole in the GCF of the 5 dogs (mean ± SD, in µg/mL) were 0 ± 0 before gel application and 47,185.75 ± 24,874.35 after 15 minutes, 26,457.34 ± 25,516.91 after 1 h, 24.18 ± 23.11 after 6 h, 3.78 ± 3.45 after 24 h and 3.34 ± 5.54 after 48 h. A single administration of the 15% metronidazole gel released the drug in the GCF of dogs in levels several-fold higher than the minimum inhibitory concentration for some periodontopathogens grown in subgingival biofilms for up to one hour, but metronidazole could be detected in the GCF at least 48 hours after the gel application.

Antimicrobial efficacy of chemical disinfectants on contaminated full metal crowns

Prosthetic restorations that have been tried in the patient's mouth are potential sources of infection. In order to avoid cross-infection, protocols for infection control should be established in dental office and laboratory. This study evaluated the antimicrobial efficacy of disinfectants on full metal crowns contaminated with microorganisms. Full crowns cast in a Ni-Cr alloy were assigned to one control group (n=6) and 5 experimental groups (n=18). The crowns were placed in flat-bottom glass balloons and were autoclaved. A microbial suspension of each type of strain - S. aureus, P. aeruginosa, S. mutans, E. faecalis and C. albicans- was aseptically added to each experimental group, the crowns being allowed for contamination during 30 min. The contaminated specimens were placed into recipients with the chemical disinfectants (1% and 2% sodium hypochlorite and 2% glutaraldehyde) for 5, 10 and 15 min. Thereafter, the crowns were placed into tubes containing different broths and incubated at 35ºC. The control specimens were contaminated, immersed in distilled water for 20 min and cultured in Thioglycollate broth at 35ºC. Microbial growth assay was performed by qualitative visual examination after 48 h, 7 and 12 days. Microbial growth was noticed only in the control group. In the experimental groups, turbidity of the broths was not observed, regardless of the strains and immersion intervals, thus indicating absence of microbial growth. In conclusion, all chemical disinfectants were effective in preventing microbial growth onto full metal crowns.

Retention force of T-bar clasps for titanium and cobalt-chromium removable partial dentures

The objective of this study was to evaluate the retention force of T-bar clasps made from commercially pure titanium (CP Ti) and cobalt-chromium (Co-Cr) alloy by the insertion/removal test simulating 5 years use. Thirty-six frameworks were cast from CP Ti (n=18) and Co-Cr alloy (n=18) with identical prefabricated patterns on refractory casts from a distal extension mandibular hemi-arch segment. The castings were made on a vacuum-pressure machine, under vacuum and argon atmosphere. Each group was subdivided in three, corresponding to 0.25 mm, 0.50 mm and 0.75 mm undercuts, respectively. No polishing procedures were performed to ensure uniformity. The specimens were subjected to an insertion/removal test and data was analyzed statistically to compare CP Ti and Co-Cr alloy in the same undercut (Student's t-test for independent samples) and each material in different undercuts (one-way ANOVA) (p=0.05). Comparisons between materials revealed significant differences (p=0.017) only for the 0.50-mm undercut. No significant differences (p>0.05) were found when comparing the same material for the undercuts. It may be concluded that for different undercuts, both Co-Cr alloy and CP Ti had no significant differences for T-bar clasps; CP Ti showed the lowest retention force values when compared to Co-Cr alloy in each undercut, but with significant difference only for the 0.50-mm undercut; and both materials maintained the retentive capacity during the simulation test.

Hand and ultrasonic instrumentation for orthograde root canal treatment of permanent teeth

Root canal treatment is a frequently performed dental procedure and is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. Removal of the necrotic tissue remnants and cleaning and shaping of the root canal are important phases of root canal treatment. Treatment options include the use of hand and rotary instruments and methods using ultrasonic or sonic equipment. OBJECTIVES: The objectives of this systematic review of randomized controlled trials were to determine the relative clinical effectiveness of hand instrumentation versus ultrasonic instrumentation alone or in conjunction with hand instrumentation for orthograde root canal treatment of permanent teeth. MATERIAL AND METHODS: The search strategy retrieved 226 references from the Cochrane Oral Health Group Trials Register (7), the Cochrane Central Register of Controlled Trials (CENTRAL) (12), MEDLINE (192), EMBASE (8) and LILACS (7). No language restriction was applied. The last electronic search was conducted on December 13th, 2007. Screening of eligible studies was conducted in duplicate and independently. RESULTS: Results were to be expressed as fixed-effect or random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confdence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. No eligible randomized controlled trials were identifed. CONCLUSIONS: This review illustrates the current lack of published or ongoing randomized controlled trials and the unavailability of high-level evidence based on clinically relevant outcomes referring to the effectiveness of ultrasonic instrumentation used alone or as an adjunct to hand instrumentation for orthograde root canal treatment. In the absence of reliable research-based evidence, clinicians should base their decisions on clinical experience, individual circumstances and in conjunction with patients' preferences where appropriate. Future randomized controlled trials might focus more closely on evaluating the effectiveness of combinations of these interventions with an emphasis on not only clinically relevant, but also patient-centered outcomes.