Navegando por Assunto "Ortodontia"

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Acesso aberto (Open Access)
Color changes of esthetic orthodontic ligatures evaluated by orthodontists and patients: a clinical study
(Universidade Federal do Pará, 2016-10) KAWABATA, Edilene; DANTAS, Vera Lucia; KATO, Carlos Brito; NORMANDO, Antonio David Corrêa
Objective: To evaluate in vivo changes in the color of esthetic elastomeric ligatures from different manufacturers. Methods: Four widely used commercial brands of elastomeric ligatures were selected and used in 20 adult patients in a splitmouth design. The ligatures were evaluated by orthodontists and patients in a double-blind manner on the day the ligatures were placed (T0 ) and 30 days after intraoral exposure (T1 ) by means of a system of staining scores. Groups were compared by Friedman test with p < 0.05. Results: Orthodontists and patients reported similar staining scores (p > 0.05). Results showed that all brands underwent significant staining when exposed to the intraoral environment. Modularcrystal MorelliTM (Sorocaba, SP, Brazil) showed the highest degree of staining with the median reaching the maximum value (3); while the other brands (3M UnitekTM, American OrthodonticsTM and GAC DentsplyTM) showed the median equal to 1 (p < 0.001). A large individual variability in the degree of staining was also found for all brands. Conclusions: All four brands of esthetic ligatures showed significant staining, which appeared to be more pronounced for the MorelliTM brand. Changes in color of the elastomeric ligatures were perceived similarly by patients and orthodontists. The industry needs to improve the color stability of esthetic ligatures.
Acesso aberto (Open Access)
Deflection test evaluation of different lots of the same nickel-titanium wire commercial brand
(Universidade Federal do Pará, 2016-02) NEVES, Murilo Gaby; LIMA, Fabrício Viana Pereira; GURGEL, Júlio de Araújo; VERCELINO, Célia Regina Maio Pinzan; REZENDE, Fernanda Soares; BRANDÃO, Gustavo Antônio Martins
Introduction: The aim of this in vitro study was to compare the elastic properties of the load-deflection ratio of orthodontic wires of different lot numbers and the same commercial brand. Methods: A total of 40 nickel-titanium (NiTi) wire segments (Morelli OrtodontiaTM - Sorocaba, SP, Brazil), 0.016-in in diameter were used. Groups were sorted according to lot numbers (lots 1, 2, 3 and 4). 28-mm length segments from the straight portion (ends) of archwires were used. Deflection tests were performed in an EMIC universal testing machine with 5-N load cell at 1 mm/minute speed. Force at deactivation was recorded at 0.5, 1, 2 and 3 mm deflection. Analysis of variance (ANOVA) was used to compare differences between group means. Results: When comparing the force of groups at the same deflection (3, 2 and 1 mm), during deactivation, no statistical differences were found. Conclusion: There are no changes in the elastic properties of different lots of the same commercial brand; thus, the use of different lots of the orthodontic wires used in this research does not compromise the final outcomes of the load-deflection ratio.
Acesso aberto (Open Access)
Distal movement of upper permanent molars using midpalatal mini-implant
(2013-04) LIRA, Ana de Lourdes Sá de; PRADO, Sávio Raimundo Lemos; ARAÚJO, Mônica Tirre; SANT'ANNA, Eduardo Franzotti; RUELLAS, Antonio Carlos de Oliveira
OBJECTIVE: To assess whether palatal mini-implants are effective as direct anchorage for distal movement of the upper molars. METHODS: It was used an acrylic model of the upper dental arch. After making a groove in the region corresponding to dental alveolus, acrylic teeth were fixed in groove with #7 wax, with the roots being previously immersed in adhesive wax. The orthodontic appliance was placed according to the Edgewise technique and then a mini-implant (SIN, São Paulo, Brazil) was inserted at the site corresponding to the palatal raphe. A 0.019 x 0.025-in stainless steel archwire was made and attached to the upper arch with elastics. A transpalatal arch bar (0.019 x 0.025in) was mounted and two hooks were soldered to it in order to retain chain elastics (Unitek, Brazil) to be connected to the mini-implant under a force of 1.5 N on each side. The maxillary model was immersed in water 40 times and photographed after each immersion, for observation of dental movements. Analysis of variance (ANOVA) and Tukey's test were employed for analyzing the obtained data. RESULTS: Molars displaced distally 3.1 mm, in average, with distal inclination ranging from 3 to 5 mm. CONCLUSIONS: Molar movements occurred due to distal inclination, with a slight rotation and no extrusive effect.
Acesso aberto (Open Access)
Evaluation of ionic degradation and slot corrosion of metallic brackets by the action of different dentifrices
(2013-02) BRANDÃO, Gustavo Antônio Martins; SIMAS, Rafael Menezes; ALMEIDA, Leandro Moreira de; SILVA, Juliana Melo da; MENEGHIM, Marcelo de Castro; PEREIRA, Antonio Carlos; ALMEIDA, Haroldo Amorim de; BRANDÃO, Ana Maria Martins
OBJECTIVE: To evaluate the in vitro ionic degradation and slot base corrosion of metallic brackets subjected to brushing with dentifrices, through analysis of chemical composition by Energy Dispersive Spectroscopy (EDS) and qualitative analysis by Scanning Electron Microscopy (SEM). METHODS: Thirty eight brackets were selected and randomly divided into four experimental groups (n = 7). Two groups (n = 5) worked as positive and negative controls. Simulated orthodontic braces were assembled using 0.019 x 0.025-in stainless steel wires and elastomeric rings. The groups were divided according to surface treatment: G1 (Máxima Proteção Anticáries®); G2 (Total 12®); G3 (Sensitive®); G4 (Branqueador®); Positive control (artificial saliva) and Negative control (no treatment). Twenty eight brushing cycles were performed and evaluations were made before (T0) and after (T1) experiment. RESULTS: The Wilcoxon test showed no difference in ionic concentrations of titanium (Ti), chromium (Cr), iron (Fe) and nickel (Ni) between groups. G2 presented significant reduction (p < 0.05) in the concentration of aluminium ion (Al). Groups G3 and G4 presented significant increase (p < 0.05) in the concentration of aluminium ion. The SEM analysis showed increased characteristics indicative of corrosion on groups G2, G3 and G4. CONCLUSION: The EDS analysis revealed that control groups and G1 did not suffer alterations on the chemical composition. G2 presented degradation in the amount of Al ion. G3 and G4 suffered increase in the concentration of Al. The immersion in artificial saliva and the dentifrice Máxima Proteção Anticáries® did not alter the surface polishing. The dentifrices Total 12®, Sensitive® and Branqueador® altered the surface polishing.
Acesso aberto (Open Access)
Evaluation of metallic brackets adhesion after the use of bleaching gels with and without amorphous calcium phosphate (ACP): in vitro study
(2013-06) MACHADO, Sissy Maria Mendes; NASCIMENTO, Diego Bruno Pinho do; SILVA, Robson Costa; LORETTO, Sandro Cordeiro; NORMANDO, Antonio David Corrêa
OBJECTIVE: To evaluate in vitro the effects of tooth whitening using gel with Amorphous Calcium Phosphate (ACP) on the bond strength of metal brackets. METHODS: Thirty-six bovine incisors were sectioned at the crown-root interface, and the crowns were then placed in PVC cylinders. The specimens were divided into 3 groups (n = 12) according to whitening treatment and type of gel used, as follows: G1 (control) = no whitening; G2 = whitening with gel not containing ACP (Whiteness Perfect - FGM), G3 = whitening with gel containing ACP (Nite White ACP - Discus Dental). Groups G2 and G3 were subjected to 14 cycles of whitening followed by an interval of 15 days before the bonding of metal brackets. Shear bond strength testing was performed on a Kratos universal test machine at a speed of 0.5 mm/min. After the mechanical test, the specimens were assessed to determine the adhesive remnant index (ARI). The results were subjected to ANOVA, Tukey's test and Kruskal-Wallis test (5%). RESULTS: Significant differences were noted between the groups. Control group (G1 = 11.10 MPa) showed a statistically higher shear bond strength than the groups that underwent whitening (G2 = 5.40 Mpa, G3 = 3.73 MPa), which did not differ from each other. There were no significant differences between the groups in terms of ARI. CONCLUSION: Tooth whitening reduces the bond strength of metal brackets, whereas the presence of ACP in the whitening gel has no bearing on the results.
Acesso aberto (Open Access)
Factors influencing orthodontic treatment time for non-surgical Class III malocclusion
(Universidade Federal do Pará, 2016-10) BICHARA, Lívia Monteiro; ARAGÓN, Mônica Lídia Castro de; BRANDÃO, Gustavo Antônio Martins; NORMANDO, Antonio David Corrêa
To improve orthodontic treatment efficiency, orthodontists must know which variables could interfere with orthodontic treatment time. Objective: To identify variables and their effect size on orthodontic treatment time of Class III malocclusion. Material and Methods: Forty-five Class III malocclusion cases were selected from 2008 patients’ records. Clinical charts, cephalometric radiographs, and pre and posttreatment dental casts were evaluated. Age, sex, PAR index at T1 and T2, overjet, missing teeth, extractions, number of treatment phases, missed appointments, appliance breakages, and cephalometric variables SNA, SNB, ANB, Wits, SnGoGn, CoA, CoGn, IMPA, 1.PP were investigated by multiple linear regression analysis and stepwise method at p<0.05. The sample was also divided into two groups: Group 0-2 (patients who had missed two clinical appointments or less) and Group >2 (patients who missed more than 2 appointments), to detect the influence of this data on treatment time and the quality of the treatment (PAR T2). Results: Average treatment time was 30.27 months. Multiple regression analysis showed that missed appointment (R2=0.4345) and appliance breakages (R2=0.0596) are the only variables able to significantly predict treatment duration. Treatment time for patients who missed more than 2 appointments was nearly one year longer. However, no significant influence on PAR T2 was observed for those patients. Conclusion: Orthodontic treatment duration in Class III patients is mainly influenced by factors related to patient compliance. Patients who missed more appointments did not show worse orthodontic finishing, but longer treatment. No occlusal, cephalometric, or demographic variable obtained before treatment was able to give some significant prediction about treatment time in Class III patients.
Acesso aberto (Open Access)
Factors related to orthodontic treatment time in adult patients
(2013-10) MELO, Ana Camila Esteves de Oliveira; CARNEIRO, Lilianne Oliveira Thiers; PONTES, Luana Farias; CECIM, Rodolpho Lobão; MATTOS, José Nazareno Rufino de; NORMANDO, Antonio David Corrêa
INTRODUCTION: The length of time that it takes an orthodontist to treat adult patients varies widely. OBJECTIVE: The aim of this study was to investigate how different variables influence treatment time. METHODS: Seventy clinical case reports of successfully treated adult patients were examined. The patients were selected from 4,723 records held by three experienced orthodontists. The influence exerted by the following variables on treatment time was assessed: age, sex, facial pattern, severity of malocclusion (measured by the PAR index), sagittal relationship of canines, type of brackets (ceramic or metal), tooth extractions, missed appointments and orthodontic appliance issues/breakages, the latter being the dependent variable. Assessment was performed by multiple linear regression analysis, followed by the stepwise method with P < 0.05. RESULTS: The number of times a patient missed their appointment (no-show) (R2 = 14.4%, p < 0.0001) and the number of appliance issues/breakages (R2 = 29.71%, p = 0.0037) significantly affected variability in treatment time, and these two variables together can predict 43.75% (R2 total) of the overall variability in treatment time. Other factors, such as canine relationship at the beginning of treatment, bracket type (metal or ceramic), tooth extractions, age at start of treatment, severity of the initial malocclusion, sex and facial pattern had no significant bearing on treatment time. CONCLUSIONS: The duration of orthodontic treatment in adults, when performed by experienced orthodontists, is mainly influenced by factors related to patient compliance. However, several factors which were not included in this study may contribute to variability in orthodontic treatment time.
Acesso aberto (Open Access)
In vivo color changes of esthetic orthodontic ligatures
(2012-10) SILVA, Andréia Viana Martins da; MATTOS, Giselle Vasconcelos de; KATO, Carlos Mario; NORMANDO, Antonio David Corrêa
OBJECTIVE: To assess the color changes that occur in four commercial brands of esthetic orthodontic elastomeric ligatures after exposure to the oral environment. METHODS: The four elastomeric ligatures manufacturers mostly mentioned by orthodontists were investigated: Morelli, Uniden, American Orthodontics (AO) and TP. The sample comprised 25 patients. The elastomeric ligatures were randomly distributed and arranged in the four dental quadrants of each patient, r for 30 days. After this period, two units of each brand were photographed in a standardized manner. Subsequently, color changes were visually evaluated and assigned a score (0, 1, 2 or 3) by a panel of four examiners. The mean scores assigned by the examiners were statistically analyzed by ANOVA and Tukey's test (p < 0.05). RESULTS: The mean pigmentation scores assigned to Morelli (1.80 ± 0.78) and Uniden (1.92 ± 0.66) elastomeric ligatures after 30 days in the oral environment were not statistically different. However, these brands were significantly more pigmented after 30 days in the oral environment (p < 0.01) compared to American Orthodontics (0.97 ± 0.6) and TP (0.83 ± 0.79). CONCLUSIONS: Although all four brands exhibited an undesirable pigmentation after 30 days in the oral environment, color change for American Orthodontics and TP Orthodontics ligatures was significantly lower than Morelli and Uniden products.
Acesso aberto (Open Access)
Influência de agentes clareadores de uso caseiro e em consultório na resistência de união braquetes ao esmalte em diferentes tempos após clareamento
(São Leopoldo Mandic, 2013-05-24) NUNES, Mauro de Amorim Acatauassú; HÖFLING, Roberta Tarkany Basting; http://lattes.cnpq.br/2395614442725255
The aim of this study was to evaluate the influence of bleaching agents on the shear bond strength of metal orthodontic brackets to enamel using a resin cementing agent; and fracture mode, at different time intervals after bleaching treatment. One-hundred-and-eighty bovine permanent incisors were sectioned and randomly divided into three groups: Group I - (control): without bleaching. Group 2: bleached with 20% Carbamide Peroxide, (Opalescence® PF) for 21 days, 10 hours/day. Group 3: bleached with 38% Hydrogen Peroxide, (Opalescence® Boost™) in two 15-minute applications every 7 days (for 21 days). After this, the groups bleached were again divided into sub-groups (n=15) according to the time interval after bleaching to perform procedures for bracket bonding to enamel: immediate, 24 hours, 7, 14, 21 and 28 days. The shear bond strength tests were performed in a universal test machine (EMIC) at a speed of 0.5mm/min and the values were recorded in MPa. After, the teeth were examined under a stereoscopic loupe at 40X magnification, to record the Adhesive Remnant Index (ARI). ANOVA showed the technique x time interaction was significant (p=0.0310). Scores were analyzed by Kruskal Wallis and Dunn tests for comparisons between times and Mann Whitney; between techniques, and comparisons with control group. The level of significance considered was 5%. As regards the Group 2, there was no statistically significant difference among time intervals. For the Group 3, there was lower bond strength of brackets to enamel in the immediate time, and this time also differed statistically from that of the Control group. Immediate time did not differ statistically from the times at 14 and 21 days. Times between 1 and 28 days also did not differ statistically among them. The fractures, were a larger number of the cohesive type at the bracket/ orthodontic resin interface. For the group in which 38% Hydrogen Peroxide was used, adhesive fractures in the enamel/ orthodontic resin region were predominant in the immediate time. Use of 20% Carbamide Peroxide, had no influence on the bond strength of orthodontic brackets; whereas the use of 38% Hydrogen Peroxide immediately before bracket bonding reduced the shear bond strength. Performing bracket bonding immediately after conclusion of bleaching treatment must be contra-indicated.
Acesso aberto (Open Access)
Um método para o retratamento da recidiva do desalinhamento dentário
(2011-10) NORMANDO, Antonio David Corrêa; CAPELOZZA FILHO, Leopoldino
INTRODUÇÃO: o ortodontista clínico deve esperar alguma perda do alinhamento dentário obtido durante o tratamento ortodôntico nos casos em que a contenção ortodôntica foi suspensa pelo profissional ou perdida pelo paciente. Nessa situação, os pacientes são, frequentemente, relutantes em novamente usar braquetes para retratar o alinhamento dentário perdido após o tratamento. OBJETIVO: esse artigo descreve o uso de uma técnica simples e eficiente para corrigir pequenas alterações do alinhamento dentário. Esse procedimento, inovador e de baixo custo, produz a resolução da recidiva em poucas semanas. A força usada para realinhar os dentes é obtida através de um fio elastomérico transparente amarrado a uma contenção fixa, de vários filamentos, colada às arcadas superior e inferior.
Acesso aberto (Open Access)
Métodos de avaliação do segmento posterior mandibular
(Universidade Estadual de Campinas, 2002-11-18) ALMEIDA, Haroldo Amorim de; ALMEIDA, Maria Helena Castro de; http://lattes.cnpq.br/0770202080280415
The aim of this study was to compare three evaluation methods of the space available in the jaw posterior segment: MERRIFIELD's (1978), RICKETTS (1976) and RICHARDSON's (1992); Sixty teleradiographs were laterally taken from the heads of sixty Brazilian leucodermas, with age ranging from 9 to 19 years oId. Ali patients presented Class II malocc1usion, division 1, Which were divided by sex into two groups: 30 male and 30 female. Based on the results of the present study it was conc1uded that there is an evident growth in the jaw posterior segment within the age of 9 to 19 years, with mean values of 10,21mm for the MERRIFIELD's method, 11,21mm for RICHARDSON's and 17,84mm for the RICKETTS method. Generally, independently of the evaluated method, it was verified that females present an earlier growth (12,17mm) than males (8,81mm), between 9 to 12 years old. For the correlation of the evaluated methods, there was no statistically significant difference by t test at the 1% level of significance (p = 0,01). The MERRIFIELD's method (1978) was the easiest to perform.
Acesso aberto (Open Access)
Partial time use of anterior repositioning splints in the management of TMJ pain and dysfunction: a one-year controlled study
(2005-12) CONTI, Paulo César Rodrigues; MIRANDA, João Evandro da Silva; CONTI, Ana Cláudia de Castro Ferreira; PAGORARO, Luiz Fernando; ARAUJO, Carlos dos Reis Pereira de
This study aimed at evaluating the effectiveness of partial use of anterior repositioning appliances in the management of TMJ pain and dysfunction when compared to stabilization splints and a control group in a one-year follow-up. Sample was initially constituted by 60 patients, randomly divided into three groups: I- stabilization splints, II- repositioning splints and III- no treatment. The whole sample was evaluated by means of TMJ and muscle palpation, mandibular AROM, analysis of occlusal contacts, joint sounds inspection and Visual Analogue Scale (VAS) for one year; 52 patients composed the final sample. A significant (after 15 days) improvement in pain report (VAS) and palpation index was found for group II (p≤0.01). The occurrence of occlusal alterations as posterior open bite or gross interferences after the splint therapy and increased muscle tenderness were not problems in this study. Similar results in joint noises reduction were observed for the entire sample. It was concluded that controlled partial use of repositioning splints is a beneficial tool in the management of intra-articular pain and dysfunction, with no risks of irreversible occlusal changes.
Acesso aberto (Open Access)
Quanto de desvio da linha média dentária superior ortodontistas e leigos conseguem perceber?
(2009-04) NORMANDO, Antonio David Corrêa; AZEVEDO, Lediana Aguiar; PAIXÃO, Patrícia Nascimento
AIM: The present study evaluated the perception degree of the upper midline deviation and crown incisor angulation among orthodontists and lay people, as well as the influence of the labial philtrum visualization as a morphological reference of the facial midline during smile examination. METHODS: in a smile picture taken from a 23 year old female, 10 year after orthodontic retention, changes were made in the upper midline, from 1mm to 4mm, and in the crown incisor angulation, from 5º to 15º, both for left side, using a image manipulation software (Adobe Photoshop 7.0). The pictures were cut out forming a group with and another without the visualization of the labial philtrum. The images obtained were examined by 24 orthodontists and 24 graduated lay people. RESULTS: Results showed that orthodontists were less tolerant to discrepancies of midline than lay people, as well as to changes in the crown incisor angulation. The orthodontists were able to observe midline deviations of 2mm and crown incisor angulation deviations starting from 5º. The lay people examiners considered as unacceptable only midline deviations starting from 3 or 4mm, depending on the labial philtrum visualization, and angulation deviations of the incisor crown starting from 10º. Labial philtrum visualization had influenced only to lay people examiners. CONCLUSIONS: It can be concluded that orthodontists are more critic when examining midline deviations and crown angulation changes than lay people examiners. The visualization of the philtrum has no influence for the orthodontist group, but had slight influence on the lay people examiners.
Acesso aberto (Open Access)
Staining of esthetic brackets by plaque disclosing solutions
(2014-06) ISMAEL, Luiza Novelino Acatauassú; NUNES, Mauro de Amorim Acatauassú; NUNES, Ana Maria Novelino Acatauassú; MOTTA, Rogério Heládio Lopes; DEMASI, Ana Paula Dias; FLÓRIO, Flávia Martão
AIM: To evaluate the staining of esthetic orthodontic brackets by plaque disclosing solutions. METHODS: Two types of brackets manufactured by GAC/DENTSPLY(r) were evaluated: ceramic (n=30) and polycarbonate (n=30). The brackets were divided into 6 groups. Two control groups (n=6) were immersed in absolute ethanol: GI - ceramic brackets and GII - polycarbonate brackets. Four experimental groups (n=12) were immersed in different plaque disclosing solutions: GIII (ceramic brackets) and GIV (polycarbonate brackets) were immersed in Replak(r); GV (ceramic brackets) and GVI (polycarbonate brackets) were immersed in Replasul "S"(r). Relative quantitative analysis of the influence of plaque disclosing tablets on bracket staining was performed using reflectance spectrophotometry of stain deposition. Exploratory analysis of the data was performed using Analysis of Variance (ANOVA) in a 2x2 factorial setup (bracket x immersion) with additional treatments (controls). RESULTS: The results demonstrated that the ceramic brackets presented the highest amount of staining when Replasul "S"(r) was used (pd"0.05). However, when Replak(r) was used, no statistically significant difference was found in comparison with the control group (p>0.05). For polycarbonate brackets, staining was detected for both disclosing solutions (p>0.05). CONCLUSIONS: The disclosing solutions caused stain formation on polycarbonate brackets and, under the tested conditions, use of Replak(r) on ceramic brackets did not cause staining.
Acesso aberto (Open Access)
Survival analysis of banding and bonding molar tubes in adult patients over a 12-month period: a split-mouth randomized clinical trial
(Universidade Federal do Pará, 2016) OEIRAS, Valéria Jacques; SILVA, Valéria Assis Almeida e; AZEVEDO, Leidiana Aguiar; LOBATO, Vanessa Soares; NORMANDO, Antonio David Corrêa
This split-mouth randomized clinical trial aimed to compare the survival rate of bonding and banding molar tubes in adult orthodontic patients. Eligibility criteria included adults (aged >18 years), no active caries, restorations, or fractures in the upper and lower molars. The main outcome was any type of first-time failure in molar tubes. A computer-generated randomization scheme was used in a 1:1 ratio. The survival rate was estimated for 32 adult patients, in whom a tube was bonded to a molar tooth using composite resin on one side and a band was cemented with glass ionomer onto the same tooth in the contralateral arch. A total of 59 banded and 59 bonded molars were followed up for 12 months. Blinding was not applicable. Survival analysis including Cox regression was used at p < 0.05. The survival rate of bonded molars was not statistically different from that of banded molars (log-rank test, p = 0.97). Hazard ratio (HR) was 0.72 (95%CI, 0.38-1.31). Bonded upper molars yielded a survival rate of 81.25% (26 out of 32) compared to 71.87% (23 out of 32) for banded upper molars. The survival rate was 66.66% (18 out of 27) for banded lower molars and 59.25% for bonded lower molars (16 out of 27). The HR for lower vs. upper arch was 2.16 (95%CI, 1.18-3.98). No serious problem was observed other than gingivitis associated with plaque accumulation. In contrast to previous studies in young patients, in adults, bonding orthodontic tubes to molars is similar to molar banding. However, both procedures had a high failure rate in the lower arch.