The effect of chlorhexidine on plaque index and mutans streptococci in orthodontic patients: A pilot study

Aim: The purpose of this study was to assess chlorhexidine effects on plaque index and salivary levels of mutans streptococci (MS) when used as the immersion solution for removable orthodontic appliances and added to their acrylic resin composition. Methods: Forty-five patients (6 to 12 years old) were randomly assigned into three groups with 15 patients each. Group I (control)—without orthodontic appliances disinfection; Group II—removable orthodontic appliances which had been immersed in 0.12% chlorhexidine digluconate overnight (8 hours), and Group III—orthodontic appliances in which 0.12% chlorhexidine digluconate solution had been incorporated into their resin composition. Saliva was collected for quantification of MS and evaluation of plaque index was performed before and after installation of orthodontic appliance at 0, 2, 4, 6, 8, and 10 weeks. Data were analyzed by using analysis of variance. Results: Number of MS colonies in saliva and plaque index showed no statistically differences among groups at the different periods (p > 0.05). Conclusions: It could be concluded that chlorhexidine incorporation into the acrylic resin of removable orthodontic appliances at 0.12% concentration and immersion of the appliance into 0.12% chlorhexidine solution were not effective in reducing plaque index and the number of MS in saliva.

Avaliação tomográfica no tratamento com Herbst em adulto jovem

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efficiency of occlusal splints on police officers with TMD

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analysis of mesiodistal angulations of preadjusted brackets

Manufacturers offer various prescriptions of preadjusted brackets for use in the "straight-wire" orthodontic technique. However, the need to incorporate bends in the rectangular wires during orthodontic finishing has led to concerns regarding the type of prescription chosen and the credibility of information provided by the manufacturer. The aim of this study was to compare the slot angulations of Roth prescription preadjusted metallic brackets for the maxillary left central incisor and maxillary left canine. For each tooth type, 10 brackets of three commercial brands (GAC, Forestadent and Morelli) were selected. Two individual metal matrices for brackets and tooth positioning were made for each group of teeth. Captured images were obtained by standardized ortho-radial photography with a digital camera. Images were exported and analyzed with the Image J software package. One-way ANOVA and Tukey statistical analyses were performed at the 5% significance level. For brackets of the maxillary left central incisor, differences in mean angulation were observed between the Morelli and GAC groups (p < 0.01) and between the Forestadent and GAC groups (p < 0.01). For brackets of the maxillary left canine, differences in mean angulation were found between the Morelli and GAC groups (p < 0.01) and between the Morelli and Forestadent groups (p < 0.05). In conclusion, despite their same prescription name, the different brands exhibited significantly different angulation measurements.

On nonlinear dynamics and control of a robotic arm with chaos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fluoride gel supplemented with sodium hexametaphosphate reduces enamel erosive wear in situ

This study evaluated the effect of fluoride gels, supplemented or not with sodium hexametaphosphate (HMP), on enamel erosive wear in situ. Twelve healthy volunteers wore palatal appliances containing four bovine enamel discs. Subjects were randomly allocated into four experimental phases (double-blind, crossover protocol) according to the gels: Placebo (no fluoride or HMP), 1% NaF, 2% NaF, and 1% NaF+9% HMP. Enamel discs were selected after polishing and surface hardness analysis, and treated only once with the respective gels prior to each experimental phase. Erosion (ERO) was performed by extra-oral immersion of the appliance in 0.05M citric acid, pH 3.2 (four times/day, five minutes each, 5 days). Additional abrasion (ERO+ABR) was produced on only two discs by toothbrushing with fluoridated dentifrice after ERO (four times/day, 30s, 5 days). The specimens were submitted to profilometry and hardness analysis. The results were analyzed by two-way ANOVA and the Student-Newman-Keuls test (p<0.05). The 1% NaF+9% HMP gel promoted significantly lower enamel wear for ERO compared to the other groups, being statistically lower than 1% NaF and Placebo for ERO+ABR. Similarly, the lowest values of integrated lesion area were found for 1% NaF+9% HMP and 2% NaF, respectively, for ERO and ERO+ABR. The addition of HMP to the 1% NaF gel promoted greater protective effect against ERO and ERO+ABR compared to the 1% NaF gel, achieving similar protective levels to those seen for the 2% NaF gel. Gel containing 1% NaF+9% HMP showed a high anti-erosive potential, being a safer alternative when compared to a conventional 2% NaF gel.

Estudo clínico comparativo da manutenção do aprofundamento de sulco nas vestibuloplastias mandibulares, através das técnicas de tuneilização submucosa e epitelização secundária

For some time, oral surgeons have tried several surgical procedures to improve the alveolar ridge for prosthetic appliance construction. The techniques used for this purpose are divided into four groups: submucosal vestibuloplasty; secondary epithelization; soft tissue grafting and transpositional flaps. Twenty patients who had problems to wear dentures due to unsatisfactory retention and stability were selected at the Oral and MaxilloFacial Surgery and Traumatology Clinic of Dental School of São José dos Campos. They were divided in two groups and operated by submucosal vestibuloplasty using stents and secondary epithelization vestibuloplasty by Clark's technique and were evaluated twelve months after operations in relationship of the sulcus depth. The results were obtained by clinical and radiological examination before and after surgery, and they are similar to those found in the literature reaching satisfactory functional judgement

Oxygen mobility in Bi:Sr:Ca:Cu:O ceramic measured using anelastic relaxation methods

Since the discovery of YBaCuO, experiments have shown that its superconducting properties are strongly affected by the oxygen content. More recently, anelastic relaxation measurements in La2CuO4+δ, showed that the decrease in the oxygen content can be related to two events. One is the decrease in mobility between two adjacent CuO planes, and the other is the increase in the number of tilting patterns of the CuO6 octahedra. In the case of the bismuth-based ceramic, it is known that the oxygen content, within some limits, does not affect its superconducting properties. In order to evaluate the mobility and the effect of the oxygen content on this material we have prepared BSCCO ceramic and tested regarding its internal friction and electrical resistivity as a function of the temperature while the oxygen content was being reduced by a sequence of vacuum annelaing at 620 K. The samples were prepared in the Bi:Sr:Ca:Cu = 2212 and 2223 proportion, using powder obtained by the sol-gel route and conventional solid state reaction. The anelastic relaxation measurements were performed using a torsion pendulum operating with frequency about 15-35 Hz between 77 to 700 K. The diffraction pattern of the as sintered and the vacuum annealed material were also presented. The results have shown complex anelastic relaxation structures that were associated to the jump of interstitial oxygen atoms between two adjacent CuO planes. The vacuum annealing showed to be deleterious to the critical temperature of the superconducting ceramic.

Oxygen Interstitial Dynamics in Bi(2)Sr(2)CaCu(2)O(8+delta) Oxides Measured by Mechanical Spectroscopy

Many researchers became interested in the discovery of Bi(2)Sr(2)CaCu(2)O(8+delta) oxides with critical temperature of around 80 K. It is known that the critical temperature is related to the CuO2 planes of the material. For this reason, the study of the interstitial oxygen in these oxides is of great relevance. The samples were prepared by means of conventional solid state reactions, through the stoichiometric mixture of precursory powders. After the sinterization, the samples were submitted to measurements of density, electrical resistivity, x-ray diffraction, scanning electron microscopy and energy dispersion spectroscopy, with the objective of performing their characterization. The measurements of mechanical spectroscopy were performed by a torsion pendulum. The results show three relaxation processes in the temperature range of 200 and 700 K, with activation energy of approximately 0.9 eV, which has been attributed to the dynamics of the interstitial oxygen present in the material.

Correção da deficiência transversa da maxila por meio da expansão rápida da maxila cirurgicamente assistida

Fundamentation: The correction of maxillary transverse deficiencies involves orthodontic and surgical procedures that can be performed before or after skeletal maturity. The surgically assisted rapid maxillary expansion (SAR ME) is performed by osteotomies through the lateral walls of the maxilla, zygomatic and canines buttresses, palatal and pterygomaxillary sutures, causing the maxillary disjunction. Followed by activation of the expander to the desired over-expansion in order to correct intercuspal later. Objective: The purpose of this study was to discuss the issues involved in the diagnosis of maxillary atresia, SAR ME indications, as well as surgical technique, through a case study. Methods: The male patient, 19 years old, had severe transverse maxillary deficiency with facial pattern III , Class III , with great lip incompetence. The patient underwent general anesthesia in a hospital environment, the osteotomies was done according to the technique described by Epker and Wolford (1980). Postoperatively, the patient underwent activations daily for 15 days and after 6 months, the orthodontist installed fixed orthodontic appliance to prepare the patient to orthognathic surgery later. Conclusion: The diagnosis by clinical evaluation and models study is essential for the indication of SAR ME and this procedure provides good predictability in the correction of transverse deficiency, with minimal morbidity.

Effects of Maternal Pb2+ poisoning during pregnancy on the development of the jaw (Meckel´s Cartilage) of rat fetus

The purpose of this study was to investigate the effects of maternal lead poisoning during pregnancy on the development of the jaw (Meckel's cartilage) of rat fetuses by histologic and morphometric methods. Pregnant rats received a single intraperitoneal injection of 2.5 mg of lead acetate/100g body weight on the 10th day of pregnancy. Meckel's cartilage of fetuses of the lead-treated group showed smaller volume density and size of the lacunae, as well as modification of the lacunae shape. Moreover, the number density of lacunae and the volume density of the matrix increased significantly in the Meckel's cartilage in treated group fetuses. The results suggest that lead poisoning during the period of organogenesis can induce disturbances in the development and differentiation of the fetal stomatognathic system. Reducing the consumption of alcoholic beberages and smoking cessation by women in childbearing age, along with a strict policy of control of the environmental lead exposure can bring great benefits to the future generations of children.

O tratamento da apneia obstrutiva do sono e a utilização de implantes osseointegráveis: revisão da literatura

The obstructive sleep apnea syndrome affects millions of people around the world. The mandibular repositioning devices have been indicated in cases of mild/moderate syndrome; however in edentulous patients its use is deficient since there is no retention. Therefore the objective of this study was to conduct a review on the use of this treatment method combined to osseointegrated implants. A search on the theme: Dental implant and sleep apnea syndromewas performed in the Medline/PubMed, ISI, Cochrane, Dentistry Oral Science, Clinical Trials, Controlled Trials, and Bireme-BvS, databases, and 22 articles were found. After anevaluation 2 studies were selected and the review was complemented with an analysis of randomized controlled trials in the previous seven bases using the key-words: Sleep apnea syndrome, Oral appliance and Randomized controlled trial. The search returned 37 articles, and after they were submitted to inclusion criteria 17 studies were selected. There are a small number of studies presenting the use of dental implants as a mean to assist the stabilization of the mandibular repositioning appliances; those that are available are case reports that focusing on the effectiveness of the technique. Studies examining the effect these appliances in dentate patients indicate improvement in the levels of apnea and snoring. The use of mandibular repositioning appliances in dentate patients is an effective technique in treatment of patients with obstructive sleep apnea syndrome mild/moderate. Randomized controlled trialsare required in order to enable an analysis of the use of mandibular repositioning devices with the aid of dental implants .

An effective technique to posterior resin composite restorations

AIM: The aim of this study is to present a clinical case in which an occlusal matrix device was used in a patient who needed to restore a posterior tooth. MATERIAL AND METHODS: A direct duplicate occlusal appliance was used (biteperf) in a patient who needed an occlusal restoration in two posterior teeth. RESULTS: Using the matrix helps having fast and accurate reproduction of the original anatomical details of the occlusal surface. The final result surprised with the presented restoration in terms of esthetic quality, despite the simplicity of the technique. CONCLUSION: Posterior teeth with initial lesions were confined to the occlusal surface of anatomically complex or fissured anatomy with or without signs of proximal caries wich are ideal candidates for this technique. The overlying enamel surface must be relatively intact; lesions of hidden or occult caries. CLINICAL SIGNIFICANCE: The aesthetic and time-saving benefits of the occlusal device (biteperf) are immediately clear. The matrix allows the fast and accurate reproduction of the anatomic details of the original occlusal surface of the tooth. The professionals who lack an artistic penchant and marked manual ability will be able to carry out excellent posterior resin composite restorations.

Tratamento compensatorio da má oclusnao de classe lll: revisão de literatura

Class III malocclusion is less common occlusal relationship, covering less than 5% of the population. There are various forms of treatment in Class III malocclusion. Depending on how the form is expressed Class III and age of the patient, the therapy may be orthopedic and orthodontic surgical orthodontics. The objective was to review the literature of the last 10 years about ways to compensatory treatment of Class III malocclusion. Several articles were published between 04/2003 and 04/2013 in the Pubmed database from the keyword "Class III malocclusion". However, only 19 articles that addressed the compensatory treatment of Class III were selected. Based on the selected items it was concluded that the treatment of Class III malocclusions in children before the peak of pubertal growth has better prognosis with greater effects orthopedic and orthodontic minor effects. The ideal treatment option for this condition is the Rapid maxillary expansion associated with maxillary protraction of the same. The treatment of Class III malocclusion in young people after the peak of pubertal growth is doubtful prognosis. You can opt to treat rapid maxillary expansion and maxillary protraction of the same or fixed appliance, however, orthopedic effects can be the same or smaller than the orthodontic effects, depending on the age of the patient. Depending on the degree of Class III malocclusion in adults, the treatment will consist of dental compensations or orthognathic surgery.

Mordida cruzada posterior, correccion y consideraciones: caso clínico con 7 años de seguimiento

Early treatment of functional unilateral posterior crossbite during the mixed dentition is extremely important for contemporary Orthodontics, provides the correct positioning of osseous bases, teeth and temporomadibular joint when the stomatognathic system is in growth and development. These results generally develop into an adequate craniofacial relationship, reducing the necessity for more complex treatments at permanent dentition. The subject of this paper was to report patient 8 years old, diagnosed with functional unilateral posterior crossbite, and was treated by an expander appliance type Quad-helix emphasizing the long-term stability. The malocclusion was corrected in 3 months of active use of the appliance, 3 months for retention purposes and followed up during 7 years post-treatment. The stability in long term of functional unilateral posterior crossbite treated is closely related with early diagnostic, the elimination of the etiological factor associated with a correct appliance and the mechanic of treatment.