Skeletal alterations associated with the use of bonded rapid maxillary expansion appliance

Bonded maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion (RME). However, there is still no consensus in the literature about its real skeletal effects. The purpose of this prospective study was to evaluate, longitudinally, the vertical and sagittal cephalometric alterations after RME performed with bonded maxillary expansion appliance. The sample consisted of 26 children, with a mean age of 8.7 years (range: 6.9-10.9 years), with posterior skeletal crossbite and indication for RME. After maxillary expansion, the bonded appliance was used as a fixed retention for 3.4 months, being replaced by a removable retention subsequently. The cephalometric study was performed onto lateral radiographs, taken before treatment was started, and again 6.3 months after removing the bonded appliance. Intra-group comparison was made using paired t test. The results showed that there were no significant sagittal skeletal changes at the end of treatment. There was a small vertical skeletal increase in five of the eleven evaluated cephalometric measures. The maxilla displaced downward, but it did not modify the facial growth patterns or the direction of the mandible growth. Under the specific conditions of this research, it may be concluded that RME with acrylic bonded maxillary expansion appliance did promote signifciant vertical or sagittal cephalometric alterations. The vertical changes found with the use of the bonded appliance were small and probably transitory, similar to those occurred with the use of banded expansion appliances.

Confiabilidade da eficiência mastigatória com beads e correlação com a atividade muscular

TEMA: a avaliação da eficiência mastigatória pela análise colorimétrica com beads, pode ser um método promissor, mas não há relatos sobre a sua confiabilidade. OBJETIVO: investigar a confiabiabilidade das beads para teste de eficiência mastigatória e a correlação com a atividade eletromiográfica dos músculos masseter e temporal anterior. MÉTODO: participaram dezenove sujeitos adultos jovens, nove do gênero masculino e dez do feminino com idades entre dezoito e vinte-oito anos, com dentição completa, sem histórico de desordem temporomandibular, trauma, cirurgia na região de cabeça e pescoço, tratamento ortodôntico ou fonoaudiológico. O teste de eficiência mastigatória foi realizado com beads nas condições: mastigação habitual, mastigação unilateral direita e esquerda, com duração de 20 segundos. Simultaneamente, foi realizada a eletromiografia. A atividade em máxima intercuspidação habitual dos dentes também foi registrada. A quantidade de fucsina liberada após a mastigação foi medida usando o espectrofotômetro Beckman DU-7 UV-Visible (Beckman Inc., Palo Alto, CA, USA). RESULTADOS: houve alta confiabilidade do teste de eficiência mastigatória (r = 0,86, p < 0,01) e correlação significante com a atividade eletromiográfica (r = 0,76, p < 0,01). Também houve correlações positivas quando as provas foram analisadas separadamente. CONCLUSÃO: o teste de eficiência mastigatória realizado com beads mostrou-se um método confiável e correlacionado positivamente à atividade eletromiográfica dos músculos temporal anterior e músculos masseter.

Analysis of TMJ vibration sounds before and after use of two types of occlusal splints

Temporomandibular joint (TMJ) sounds are important and common physical signs of temporomandibular disorders (TMD). The aim of this study was to evaluate the influence of the effect of the use of occlusal bite splints (stabilizing and repositioning) on the sounds produced in the TMJ, by means of the electrovibratography (EVG). Thirty-one patients with TMD from the Dental School of Ribeirão Preto, University of São Paulo, Brazil were selected for this study. Group 1 (n=23) wore stabilizing bite splints and Group 2 (n=8) used anterior repositioning splints. Before and after treatment with occlusal splints both groups were analyzed using the SonoPAK Q/S recording system (BioResearch System, Inc.). The treatments with stabilizing bite splints were satisfactory, since they reduced the total amount of the sound energies (p<0.05), but the use of anterior repositioning splints for no more than 4 weeks produced significantly better results (p<0.01). The total amount of vibration energy involved in the vibrating movements of the TMJ showed significant improvement using anterior repositioning splints.

Reviewed evidence about the safety of the daily use of alcohol-based mouthrinses

Current scientific knowledge provides clear evidence that alcohol-based mouthwashes can be beneficial in a daily oral health routine, including dental hygiene and plaque control. Several issues are worth discussing, in spite of the wealth of supporting evidence. Despite some undesirable effects to some people, like burning sensation, and some contraindications, like the use by infants, alcohol addicts and patients with mucosal injuries, there is no reason to avoid the use of alcohol-containing mouthwashes as long as they are used following proper guidance by dental professionals and the manufacturers' instructions. The alleged correlation between oral cancer and alcohol-based mouthrinses presents so little, weak, inconsistent and even contradictory evidence in the literature that any kind of risk warning to patients would be uncalled for. Antimicrobial mouthrinses are safe and effective in reducing plaque and gingivitis, and should be part of a comprehensive oral health care regimen that includes brushing, flossing and rinsing to prevent or minimize periodontal disease.

Use of chewing gum containing 15% of xylitol and reduction in mutans streptococci salivary levels

Frequent use of Xylitol may decrease the S. mutans levels. However, very little is known about whether this effect on the levels of cariogenic bacteria is maintained after the interruption of short-term usage of xylitol. This study aimed at evaluating changes in mutans streptococci (MS) salivary levels after using a chewing gum containing xylitol. Twelve volunteers harboring > 10(5) CFU MS/ml saliva levels were asked to chew Happydent-xylit® for 5 minutes, 5 X/day, for 30 days. Saliva samples were collected at baseline, at 30 days after xylitol usage began, and at 30 days beyond its interruption. MS salivary levels were estimated. The average salivary levels of MS in the ten subjects who completed the study were 13.17 (NL-CFU) at baseline (A). After the 30 days experimental period (B), this average decreased to 9.45 (NL-CFU). Nine of ten subjects studied showed a reduction in MS salivary levels in relation to baseline, whereas salivary levels were maintained in the remaining subject. At thirty days beyond the interruption of xylitol usage (C), the average levels of MS were still reduced to 10.31 (NL-CFU). Multiple sample comparison using the Bonferroni test revealed that the decrease in MS levels observed from baseline (A) to the time immediately after 30 days of xylitol usage (B) was statistically significant (p < 0.05), and those levels were still decreased between baseline and 30 days beyond the interruption of xylitol usage (C). So, the use of xylitol induced a reduction in MS salivary levels after a short period of usage which persisted beyond its interruption.

Use of flowable composite as intermediary layer in non-carious cervical lesions restored with composite resin: 48-month follow-up

PURPOSE: In this case report, the clinical performance of a microhybrid resin composite placed with or without a flowable resin composite was compared, over a 48-month period. CASE DESCRIPTION: The patient of this case report presented 2 pairs of equivalent cervical abfraction lesions, under occlusion. Four restorations were placed in teeth 34, 35, 44 and 45. The restorations were divided into groups (Single Bond + Filtek-Flow + Filtek Z250 or Single Bond + Filtek Z250) and the materials were applied according to the manufactures instructions. Two previously calibrated operators placed the restorations and two other independent examiners evaluated the restorations at baseline and after 48 months, according to the USPHS criteria and modified criteria for color match. CONCLUSION: After 48 months of evaluation the lesions restored with Filtek-Flow as a liner under Filtek Z250 did not show better clinical performance than the restorations without Filtek-Flow. All restorations showed a trend toward dark yellowing after 48 months.

Psoríase na infância e na adolescência

A psoríase é doença inflamatória crônica, imunologicamente mediada, recorrente e de caráter universal. Aproximadamente um terço dos adultos acometidos refere início da doença antes dos 16 anos de idade. Quanto mais precoce, mais grave tende a ser a evolução do quadro. Em crianças, as lesões podem ser fisicamente desfigurantes, causando prejuízos psicológicos e evidente comprometimento da qualidade de vida. As medicações sistêmicas utilizadas na psoríase, bem como a fototerapia, têm indicação limitada na infância, devido aos efeitos cumulativos das drogas, à baixa aceitação e ao risco de teratogenicidade. Nesta seção, discutiremos as principais manifestações clínicas da psoríase na infância e na adolescência, bem como os diagnósticos diferenciais, opções terapêuticas e prognóstico.

Vancomycin use in a brazilian teaching hospital: comparison with the Hospital Infection Controlpractices Advisory Committee Guidelines (HICPAC)

This study describes vancomycin prescribing patterns in an average complexity hospital and compare the guidelines proposed by the Hospital Infection Control Practices Advisory Committee (HICPAC). The study was conducted in a 256-bed secondary-care hospital. Data were collected of all patients given vancomycin from March 2003 to February 2004, using a standardized chart-extraction form designed. Appropriate and inappropriate use was reviewed according to the Hospital Infection Control Practices Advisory Committee (HICPAC) guidelines on prudent vancomycin use. Out of 118 prescriptions, 95 (80.5%) were considered appropriate. Out of these 95 orders, 77 (81.1%) were administered for empiric treatment of suspected Gram-positive infections, 17 (17.9%) were administered for treatment of proven Gram-positive infections (76.5% identified as Staphyloccocus aureus-like agents) and 1 (1.0%) for beta-lactam allergy. The majority of the patients (96.6%) had recently used an antimicrobial medication (3 months). The mean pre-treatment hospitalization period was 11±10 days. Out of the 118 treatments, 67 (56.8%) were for nosocomial infections. The more frequent indications for vancomycin use were pneumonia (48.3%) and primary sepsis (18.6%), accounting for more than 66% of all treatments. No restriction policy was suggested because vancomycin use was considered adequate in the majority of the treatment cases. The broad empiric use of this antimicrobial was greater than expected in the institution and its use should be revised.

Polyamine patterns in haploid and diploid tobacco tissues and in vitro cultures

The aim of this work was to determine PAs levels in pith tissues and callus cultures from haploid and diploid tobacco plants, explanted from the apical and basal regions of the stem. These explants were cultured in an RM-64 medium supplied with IAA and kinetin, under light or in the dark, during successive subcultures. PAs levels followed a basipetal decrease in diploid and an increase in haploid, pith tissues. A similar pattern of total PAs (free + conjugated) was observed for the callus of diploid and haploid plants maintained in the light, and for the haploid callus in the dark, whereas the diploid callus in the dark showed a constant increase in total PAs levels until the end of culture. The PA increase in the diploid callus in the dark was related to free Put levels increase. The ploidy status of the plants could express different PA gradients together with the plant pith and in vitro callus cultures.

Use of chromosome microdissection in fish molecular cytogenetics

Chromosome microdissection is a technique in which whole chromosomes or chromosomal segments are dissected under an inverted microscope yielding chromosome-specific sequences. Several protocol modifications introduced during the past 15 years reduced the number of chromosomes required for most applications. This is of particular interest to fish molecular cytogenetics, since most species present highly uniform karyotypes which make impossible the collection of multiple copies of the same chromosome. Probes developed in this manner can be used to investigate chromosome homologies in closely related species. Here we describe a protocol recently used in the gymnotiform species group Eigenmannia and review the major steps involved in the generation of these markers focusing on protocol modifications aiming to reduce the number of required chromosomes.

Repeated exposure of adolescent rats to oral methylphenidate does not induce behavioral sensitization or cross-sensitization to nicotine

Several lines of evidence indicate that the use of stimulant drugs, including methylphenidate (MPD), increases tobacco smoking. This has raised concerns that MPD use during adolescence could facilitate nicotine abuse. Preclinical studies have shown that repeated treatment with an addictive drug produces sensitization to that drug and usually cross-sensitization to other drugs. Behavioral sensitization has been implicated in the development of drug addiction. We examined whether repeated oral MPD administration during adolescence could induce behavioral sensitization to MPD and long-lasting cross-sensitization to nicotine. Adolescent male Wistar rats were treated orally with 10 mg/kg MPD or saline (SAL) from postnatal day (PND) 27 to 33. To evaluate behavioral sensitization to MPD in adolescent rats (PND 39), the SAL pretreated group was subdivided into two groups that received intragastric SAL (1.0 mL/kg) or MPD (10 mg/kg); MPD pretreated rats received MPD (10 mg/kg). Cross-sensitization was evaluated on PND 39 or PND 70 (adulthood). To this end, SAL- and MPD-pretreated groups received subcutaneous injections of SAL (1.0 mL/kg) or nicotine (0.4 mg/kg). All groups had 8 animals. Immediately after injections, locomotor activity was determined. The locomotor response to MPD challenge of MPD-pretreated rats was not significantly different from that of the SAL-pretreated group. Moreover, the locomotor response of MPD-pretreated rats to nicotine challenge was not significantly different from that of the SAL-pretreated group. This lack of sensitization and cross-sensitization suggests that MPD treatment during adolescence does not induce short- or long-term neuroadaptation in rats that could increase sensitivity to MPD or nicotine.

Drug consumption among medical students in São Paulo, Brazil: influences of gender and academic year

OBJECTIVE: To analyze alcohol, tobacco and other drug use among medical students. METHOD: Over a five-year period (1996-2001), we evaluated 457 students at the Universidade de São Paulo School of Medicine, located in São Paulo, Brazil. The students participated by filling out an anonymous questionnaire on drug use (lifetime, previous 12 months and previous 30 days). The influence that gender and academic year have on drug use was also analyzed. RESULTS: During the study period, there was an increase in the use of illicit drugs, especially inhalants and amphetamines, among the medical students evaluated. Drug use (except that of marijuana and inhalants) was comparable between the genders, and academic year was an important influencing factor. DISCUSSION: Increased inhalant use was observed among the medical students, especially among males and students in the early undergraduate years. This is suggestive of a specific behavioral pattern among medical students. Our findings corroborate those of previous studies. CONCLUSION: Inhalant use is on the rise among medical students at the Universidade de São Paulo School of Medicine. Because of the negative health effects of illicit drug use, further studies are needed in order to deepen the understanding of this phenomenon and to facilitate the development of preventive measures.

Neuromodulation approaches for the treatment of major depression: challenges and recommendations from a working group meeting

The use of neuromodulation as a treatment for major depressive disorder (MDD) has recently attracted renewed interest due to development of other non-pharmacological therapies besides electroconvulsive therapy (ECT) such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), and vagus nerve stimulation (VNS). METHOD: We convened a working group of researchers to discuss the updates and key challenges of neuromodulation use for the treatment of MDD. RESULTS: The state-of-art of neuromodulation techniques was reviewed and discussed in four sections: [1] epidemiology and pathophysiology of MDD; [2] a comprehensive overview of the neuromodulation techniques; [3] using neuromodulation techniques in MDD associated with non-psychiatric conditions; [4] the main challenges of neuromodulation research and alternatives to overcome them. DISCUSSION: ECT is the first-line treatment for severe depression. TMS and tDCS are strategies with a relative benign profile of side effects; however, while TMS effects are comparable to antidepressant drugs for treating MDD; further research is needed to establish the role of tDCS. DBS and VNS are invasive strategies with a possible role in treatment-resistant depression. In summary, MDD is a chronic and incapacitating condition with a high prevalence; therefore clinicians should consider all the treatment options including invasive and non-invasive neuromodulation approaches.

A prática de exercícios físicos em pacientes com transtornos alimentares

CONTEXTO: Diferentes estudos discutem a relação da prática excessiva de exercícios físicos com transtornos alimentares como estratégia para perda de peso. OBJETIVO: Revisar a literatura sobre a prática de exercícios físicos em pacientes com transtornos alimentares, discutindo definições, critérios diagnósticos e propostas terapêuticas. MÉTODOS: Levantamento bibliográfico foi realizado por meio de MedLine, LiLacs e Cochrane Library, com os termos "transtornos alimentares", "anorexia", "bulimia", "exercício físico excessivo", "atividade física", "exercício obrigatório", "exercício compulsivo" e "exercício excessivo". RESULTADOS: Dos 80 artigos encontrados, foram selecionados 12 que incluíam a investigação de um padrão de atividade física considerado excessivo em indivíduos acima dos 18 anos e uso de algum instrumento de avaliação para essa finalidade. A prática de exercícios físicos em pacientes com transtornos do comportamento alimentar é revisada. CONCLUSÃO: Não há consenso sobre critérios diagnósticos e instrumentos para considerar o exercício físico como inadequado ou excessivo e seu uso como recurso para perder peso. Por outro lado, a prática de exercícios físicos durante o tratamento de pacientes com transtornos alimentares pode ser benéfica desde que orientada e supervisionada.

The use of a graphite-silicone rubber composite electrode in the determination of rutin in pharmaceutical formulation

The possibility of using a graphite silicone-rubber composite electrode (GSR) in a differential pulse voltammetric(DPV) procedure for rutin (vitamin P) determination is described. Cyclic voltammograms of rutin presented a reversible pair of oxidation/reduction peaks respectively at 0.411 and 0.390 V (vs. SCE) at the GSR surface in Britton-Robinson(B-R) buffer solution pH 4.0. In DPV after optimization of conditions, an oxidation peak at 0.370 V (vs. SCE) was used to quantitative determination of rutin in B-R buffer solution pH 4.0. In this case a linear dynamic range of 5.0×10-8 to 50.0×10-8 mol L-1 was observed with a detection limit of 1.8×10-8 mol L-1 for the analyte. Recoveries from 94 to 113% were observed. The electrode surface was renewed by polishing after each determination, with a repeatability of 1.09 ± 0.06 µA (n = 10) peak current. Rutin was determined in a pharmaceutical formulation using the proposed electrode and the results agreed with those from an official method within 95% confidence level.