Artigos Científicos - FOUFPA/ICS

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2147

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Adesivos autocondicionantes (passo único) - estabilidade em longo prazo
(2009-02) MACHADO, Sissy Maria Mendes; NORMANDO, Antonio David Corrêa; SOUZA JUNIOR, Mario Honorato Silva e
O trabalho não apresenta resumo.
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Adhesive systems: important aspects related to their composition and clinical use
(2010-06) SOUZA JUNIOR, Mario Honorato Silva e; CARNEIRO, Karina Gama Kato; LOBATO, Marcelo Figueiredo; SOUZA, Patrícia de Almeida Rodrigues Silva e; GÓES, Mário Fernando de
This literature review article addresses the types and the main components of different etch-and-rinse and self-etch adhesive systems available in the market, and relates them to their function, possible chemical interactions and influence of handling characteristics. Scanning electron microscopy (SEM) images are presented to characterize the interface between adhesives and dentin. Adhesive systems have been recently classifed according to their adhesion approaches in etch-and-rinse, self-etch and glass ionomer. The etch-and-rinse systems require a specifc acid-etch procedure and may be performed in two or three steps. Self-etch systems employ acidic monomers that demineralize and impregnate dental substrates almost at the same time. These systems are separated in one or two steps. Some advantages and defciencies were noted for etch-and-rinse and self-etch approaches, mainly for the simplifed ones due to some chemical associations and interactions. The SEM micrographs illustrate different relationships between adhesive systems and dental structures, particularly dentin. The knowledge of composition, characteristics and mechanisms of adhesion of each adhesive system is of fundamental importance to permit the adoption of ideal bonding strategies under clinical conditions.
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Air-powder polishing on self-ligating brackets after clinical use: effects on debris levels
(Universidade Federal do Pará, 2016-10) ARAGÓN, Mônica Lídia Castro de; LIMA, Leandro Santiago; NORMANDO, Antonio David Corrêa
Introduction: Debris buildup on brackets and arch surfaces is one of the main factors that can influence the intensity of friction between bracket and orthodontic wire. Objective: This study sought to evaluate the effect of air-powder polishing cleaning on debris levels of self-ligating ceramic brackets at the end of orthodontic treatment, compared to the behavior of conventional brackets. Methods: Debris levels were evaluated in metal conventional orthodontic brackets (n = 42) and ceramic self-ligating brackets (n = 42) on canines and premolars, arranged in pairs. There were brackets with and without air-powder polishing. At the end of orthodontic treatment, a hemiarch served as control and the contralateral hemiarch underwent prophylaxis with air-powder polishing. Debris buildup in bracket slots was assessed through images, and Wilcoxon test was used to analyze the results. Results: The median debris levels were statistically lower in the conventional metal brackets compared to self-ligating ones (p = 0.02), regarding brackets not submitted to air-powder polishing. Polishing significantly reduced debris buildup to zero in both systems, without differences between groups. Conclusions: Ceramic self-ligating brackets have a higher debris buildup in comparison to conventional metal brackets in vivo, but prophylaxis with sodium bicarbonate jet was effective in reducing debris levels in self-ligating and also in conventional brackets.
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Alterations in plaque accumulation and gingival inflammation promoted by treatment with self-ligating and conventional orthodontic brackets
(Universidade Federal do Pará, 2015-04) CARDOSO, Mauricio de Almeida; SARAIVA, Patrícia Pinto; BRANGELI, Liliana Ávila Maltagliati; RHODEN, Fernando Kleinübing; COSTA, Carla Cristina Alvarenga ; NORMANDO, Antonio David Corrêa; CAPELOZZA FILHO, Leopoldino
Objective: The aim of the present study was to evaluate, comparatively, the periodontal response during orthodontic treatment performed with self-ligating and conventional brackets.Methods: Sixteen Caucasian individuals of both sexes, aged between 12 and 16 years old and in permanent dentition were selected. Eight individuals were treated with conventional brackets installed on the lower dental arch and self-ligating brackets on the upper arch. Another eight individuals received self-ligating brackets in the lower arch and conventional brackets in the upper arch. The subjects received material and instructions for oral hygiene. Visible plaque index (VPI), gingival bleeding index (GBI) and clinical attachment level (CAL) were evaluated just after installation of orthodontic appliances, and 30, 60 and 180 days later. Mann-Whitney test was used to compare differences between groups (self-ligating and conventional), twoway ANOVA followed by Tukey’s test was used to assess CAL at each site of each tooth. Significance level was set at 5%. Results: No significant changes were found with regard to the assessed parameters (VPI, GBI and CAL) in either one of the systems.Conclusion: No significant changes were found with regard to the periodontal response to orthodontic treatment for the variables assessed and between subjects receiving passive self-ligating and conventional brackets. All individuals had received oral hygiene instructions and had their periodontal conditions monitored.
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Análise da correlação entre a angulação (mesiodistal) dos caninos e a inclinação (vestibulolingual) dos incisivos
(2011-06) OHASHI, Amanda Sayuri Cardoso; NASCIMENTO, Karen Costa Guedes do; NORMANDO, Antonio David Corrêa
OBJECTIVE: To assess the degree of correlation between canine angulation and incisor inclination. METHODS: Mesiodistal angulation of canines and labiolingual inclination of incisors were obtained by means of digital graphics software (ImageTool®) from standardized photographs of the casts of 60 patients. Incisor inclination was also assessed by lateral cephalometric radiographs. RESULTS: Random error showed a variation of around 2° in measurements made on the casts (1.8-2.5), while systematic error, measured by the intraclass correlation test, displayed excellent reproducibility for both methods used in this study (p<0.001, r=0.84-0.96). Linear correlation tests revealed a significant positive correlation between canine angulation and incisor inclination in the maxillary arch (r=0.3, p<0.05) and even more significantly in the mandibular arch (r=0.46 to 0.51, p<0.001), when both were measured on the casts. When incisor inclination was examined by cephalometrics, correlation level was statistically insignificant for maxillary incisors (r=0.06 to 0.21, p>0.05) and varied widely in the mandibular arch (r=0.14 to 0.50). CONCLUSIONS: The introduction of changes in the angulation of canines with the aim of monitoring compensations observed in incisor inclination is warranted, especially in the lower arch.
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Análise do emprego do cálculo amostral e do erro do método em pesquisas científicas publicadas na literatura ortodôntica nacional e internacional
(2011-12) NORMANDO, Antonio David Corrêa; ALMEIDA, Marco Antonio de Oliveira; QUINTÃO, Cátia Cardoso Abdo
To evaluate, quantitatively, how often the researchers of orthodontic science have used the calculation of sample size and evaluated the method error in studies published in Brazil and in the United States of America.
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Analysis of the mental foramen using cone beam computerized tomography
(Universidade Federal do Pará, 2015-08) SAITO, Kunihiro; ARAÚJO, Ney Soares de; SAITO, Miki Taketomi; PINHEIRO, João de Jesus Viana; CARVALHO, Pedro Luiz de
Introduction: Knowledge of the anatomical structures located in the region between the mental foramina is of critical importance in pre-operative planning. Objective: To evaluate the position of the mental foramen relative to the apices of the teeth and the distance to the edges of the mandible, using cone beam computerized tomography. Material and method: One hundred cone beam computerized tomographs of the mandible were evaluated; the tomographs were taken using a single tomographic device. Each image chosen was evaluated repeatedly from both sides of the mandible, the position of the mental foramen, indicating the region in which the foramen was found and the measures of the mental foramen, the lingual cortex and the mandibular base. Initially, the data were analyzed descriptively. A value of p<0.05 was chosen as the level of significance. Result: Forty-two percent of the mental foramina were located in the apex of the second pre-molar. The lingual margin of the mental foramen was located, on average, 3.1mm from the lingual cortex. The lower margin of the mental foramen was located 7.25 mm above the lower edge of the mandible. Conclusion: The mental foramen was located more frequently at a level of the apices of the second pre-molars, with a distance to the lingual cortex, on average, of 3.1mm and to the base of the mandible, on average, of 7.25 mm.
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Angulação dos caninos em indivíduos portadores de má oclusão de Classe I e de Classe III: análise comparativa através de um novo método utilizando imagens digitalizadas
(2010-10) AZEVEDO, Lucyana Ramos; TORRES, Tatiane Barbosa; NORMANDO, Antonio David Corrêa
OBJECTIVES: This study aimed to determine the mesiodistal angulation of canine crowns in individuals with Class III malocclusion in comparison with Class I individuals. METHODS: Measurements were taken from digital photographs of plaster models and imported into an imaging program (Image Tool). These procedures were repeated to assess random method error (Dahlberg's formula), and analyze reproducibility by intraclass correlation. The sample consisted of 57 patients with complete permanent dentition, untreated orthodontically and divided into two groups according to their malocclusion: Group I consisted of 33 patients with Class I malocclusion, 16 males and 17 females, mean age 27 years; Group II comprised 24 patients with Class III malocclusion, 20 males and 4 females, mean age 22 years. RESULTS: Random error for canine angulation ranged from 1.54 to 1.96 degrees. Statistical analysis showed that the method presented an excellent reproducibility (p<0.01). Results for canine crown angulation showed no statistically significant difference between maxillary canines in the Class I and Class III groups, although canine angulation exhibited, on average, 2 degrees greater angulation in Class III individuals. Mandibular canines, however, displayed a statistically significant difference on both sides between Class I and Class III groups (p = 0.0009 and p = 0.0074). Compared with Class I patients, angulation in Class III patients was lower in mandibular canines and tended to follow the natural course of dentoalveolar compensation, routinely described in the literature. CONCLUSION: The results suggest that dental compensation often found in literature involving the incisors region, also affects canine angulation, especially in the lower arch.
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Avaliação das ações de saúde bucal no Programa Saúde da Família no distrito de Mosqueiro, Pará
(Universidade Federal do Pará, 2008-02) EMMI, Danielle Tupinambá; BARROSO, Regina Fátima Feio
The extension of Brazil's Family Health Program Teams through the introduction of Oral Health Teams (OHT) as required by Decree N° 1,444 dated December 28, 2000, was an important step in the restructuring of the Oral Healthcare System, ensuring easier access to good quality dental care and treatment for less privileged segments of the population. In the Mosqueiro district of Pará State, an Oral Health Team was added to the Family Health Program in 2002, working closely with the local community through home calls and school visits, as well as at the Family Health Unit. In order to assess these Oral Health activities, 103 users of the Family Health Program Unit responded to a questionnaire with closed and semi-open questions in July 2004. The resulting data were tabulated, showing that most of these users were young adult women with high school diplomas but lacking access to higher education. This public felt that Oral Health quality had improved considerably, being satisfied with the performance of the current team.
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Avaliação do conhecimento em odontologia e educação física acerca dos protetores bucais
(Universidade Federal do Pará, 2009-08) SIZO, Sérgio Rodrigues; SILVA, Edilson Santos da; ROCHA, Max Pinto da Costa da; KLAUTAU, Eliza Burlamaqui
This study had the aim to assess the level of knowledge of 150 Odontology and Physical Education undergraduation students concerning mouth guards in the city of Belém, Brazil. Besides that, we tried to provide further information to these future professionals through speeches and distribution of folders in which the main focus was the mouth guards, their indications, types as well as hygienization and storage. The participants in the research were in the last year of their specific undergraduation courses. The analysis of the results showed that 68% of the interviewed students still do not have suitable information on the mouth guards, but despite of that, in their majority they are aware of the risks many athletes face in sports which have physical impact. The authors believe the spread of the information on the use of mouth guards in sportive practice is relevant and aims to prevent trauma and promote health of general population.
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Changes in lower dental arch dimensions and tooth alignment in young adults without orthodontic treatment
(Universidade Federal do Pará, 2015-06) MAUAD, Bruno Aldo; SILVA, Robson Costa; ARAGÓN, Mônica Lídia Castro de; PONTES, Luana Farias; SILVA JÚNIOR, Newton Guerreiro da; NORMANDO, Antonio David Corrêa
Objective: The aim of this longitudinal study, comprising young adults without orthodontic treatment, was to assess spontaneous changes in lower dental arch alignment and dimensions. Methods: Twenty pairs of dental casts of the lower arch, obtained at different time intervals, were compared. Dental casts obtained at T1 (mean age = 20.25) and T2 (mean age = 31.2) were compared by means of paired t-test (p < 0.05). Results: There was significant reduction in arch dimensions: 0.43 mm for intercanine (p = 0.0089) and intermolar (p = 0.022) widths, and 1.28 mm for diagonal arch length (p < 0.001). There was a mild increase of approximately 1 mm in the irregularity index used to assess anterior alignment (p < 0.001). However, regression analysis showed that changes in the irregularity index revealed no statistically significant association with changes in the dental arch dimensions (p > 0.05). Furthermore, incisors irregularity at T2 could not be predicted due to the severity of this variable at T1 (p = 0.5051). Conclusion: Findings suggest that post-growth maturation of the lower dental arch leads to a reduction of dental arch dimensions as well as to a mild, yet significant, increase in dental crowding, even in individuals without orthodontic treatment. Furthermore, dental alignment in the third decade of life cannot be predicted based on the severity of dental crowding at the end of the second decade of life
Acesso aberto (Open Access)
Cleansing orthodontic brackets with air-powder polishing: effects on frictional force and degree of debris
(Universidade Federal do Pará, 2016-08) LEITE, Brisa dos Santos; FAGUNDES, Nathália Carolina Fernandes; ARAGÓN, Mônica Lídia Castro de; DIAS, Carmen Gilda Barroso Tavares; NORMANDO, Antonio David Corrêa
Introduction: Debris buildup on the bracket-wire interface can influence friction. Cleansing brackets with air-powder polishing can affect this process. Objective: The aim of this study was to evaluate the frictional force and amount of debris remaining on orthodontic brackets subjected to prophylaxis with air-powder polishing. Methods: Frictional force and debris buildup on the surface of 28 premolar brackets were evaluated after orthodontic treatment. In one hemiarch, each bracket was subjected to air-powder polishing (n = 14) for five seconds, while the contralateral hemiarch (n = 14) served as control. Mechanical friction tests were performed and images of the polished bracket surfaces and control surfaces were examined. Wilcoxon test was applied for comparative analysis between hemiarches at p < 0.05. Results: Brackets that had been cleaned with air-powder polishing showed lower friction (median = 1.27 N) when compared to the control surfaces (median = 4.52 N) (p < 0.01). Image analysis showed that the control group exhibited greater debris buildup (median = 2.0) compared with the group that received prophylaxis with air-powder polishing (median = 0.5) (p < 0.05). Conclusion: Cleansing orthodontic brackets with air-powder polishing significantly reduces debris buildup on the bracket surface while decreasing friction levels observed during sliding mechanics.
Acesso aberto (Open Access)
Clinical evaluation of multisurface ART restorations
(2005-03) CEFALY, Daniela Francisca Gigo; BARATA, Terezinha de Jesus Esteves; TAPETY, Celiane Mary Carneiro; BRESCIANI, Eduardo; NAVARRO, Maria Fidela de Lima
The aim of this study was to evaluate the performance of two different glass-ionomer cements: a high-density (Ketac Molar - ESPE) and a resin-modified cement (Fuji VIII – GC) using the Atraumatic Restorative Treatment technique to restore multisurface cavities in permanent teeth. A total of 60 ART restorations (30 with each material) were placed in schoolchildren (9-16 years of age) by two operators. After a period of 6 months, two independent examiners evaluated 59 restorations according to the criteria used in previous ART studies. Data were submitted to McNemar and Fischer tests. The success rate of the treatment was 98.3%. One restoration (Ketac Molar) was replaced by another material and was recorded as failure. The success rates of the restorations were 100% and 96.6% for Fuji VIII and Ketac Molar, respectively. There was no statistically significant difference in the restorations success between baseline and 6 months (p>0.05). In the same way, no significant differences were found between materials, cavity types or operators (p>0.05). The ART approach was highly appropriate and effective in restorations involving two or more tooth surfaces, after 6 months. The results showed a promising performance of the ART technique with both materials.
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Clinical evaluation of postoperative sensitivity using self-etching adhesives containing glutaraldehyde
(2010-09) CHERMONT, Armando Brito; CARNEIRO, Karina Gama Kato; LOBATO, Marcelo Figueiredo; MACHADO, Sissy Maria Mendes; SOUZA JUNIOR, Mario Honorato Silva e
The present clinical study aimed to assess the postoperative sensitivity (POS) after 48 hours and seven days in occlusal restorations bonded with three different adhesive systems, two of them containing glutaraldehyde. The restorative procedures were performed using the three-step etch-and-rinse Adper SBMP-Plus adhesive (SBMP), the two-step etch-and-rinse Gluma Comfort One Bond + Desensitizer adhesive (GC+D) and the all-in-one self-etching/priming I Bond (IB) adhesive, which also has glutaraldehyde in its formula. All cavities were restored with Filtek Supreme nanoparticle composite resin. After 48 hours and seven days the patients were recalled and the postoperative sensitivity evaluated. The data analyzed by non-parametric Friedman test showed no significant differences in POS among the three tested groups after 48 hours and seven days.
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Coesão familiar associada à saúde bucal, fatores socioeconômicos e comportamentos em saúde
(2013-08) FERREIRA, Luale Leão; BRANDÃO, Gustavo Antônio Martins; GARCIA, Gustavo; BATISTA, Marília Jesus; COSTA, Ludmila da Silva Tavares; AMBROSANO, Gláucia Maria Bovi; POSSOBON, Rosana de Fátima
Overall health surveys have related family cohesion to socio-economic status and behavioral factors. The scope of this study was to investigate the association between family cohesion and socio-economic, behavioral and oral health factors. This was a, cross-sectional study with two-stage cluster sampling. The random sample consisted of 524 adolescents attending public schools in the city of Piracicaba-SP. Variables were evaluated by self-applied questionnaires and caries and periodontal disease were assessed by DMF-T and CPI indices. The adolescent's perception of family cohesion was assessed using the family adaptability and cohesion scale. Univariate and multinomial logistic regression shows that adolescents with low family cohesion were more likely than those with medium family cohesion to have low income (OR 2,28 95% CI 1,14- 4,55), presence of caries (OR 2,23 95% CI 1,21-4,09), less than two daily brushings (OR 1,91 95% CI 1,03-3,54). Adolescents with high family cohesion were more likely than those with medium family cohesion to have high income and protective behavior against the habit of smoking. Thus, the data shows that adolescent perception of family cohesion was associated with behavioral, socio-economic and oral health variables, indicating the importance of an integral approach to patient health.
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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.
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Compressive strength of esthetic restorative materials polymerized with quartz-tungsten-halogen light and blue LED
(2009) SILVA, Cecy Martins; DIAS, Katia Regina Hostilio Cervantes
This study compared the compressive strength of a composite resin and compomer photoactivated with a conventional quartz-tungsten halogen-light (XL 3000, 3M/SPE) and a blue light-emitting diode (LED) (SmartLite PS; Dentsply/De Trey). Forty disc-shaped specimens were prepared using a split polytetrafluoroethylene matrix (4.0 mm diameter x 8.0 mm hight) in which the materials were inserted incrementally. The curing time of each increment was of 40 s with the QTH and 10 s with the LED. The specimens were randomly assigned to 4 groups (n=10), according to the light source and the restorative material. After storage in distilled water at 37oC ± 2oC for 24 h, the specimens was tested in compressive strength in a universal testing machine with load cell of 500 kgf running at a crosshead speed of 0.5 mm/min. Data (in MPa) were analyzed statistically by ANOVA and Student-Newman-Keuls test (p<0.05). For the composite resin, light curing with the QTH source did not produce statistically significant difference (p>0.05) in the compressive strength when compared to light curing with the LED source. However, light curing of the compomer with the QTH source resulted in significantly higher compressive strength than the use of the LED unit (p>0.05). The composite resin presented significantly higher (p>0.05) compressive strength than the compomer, regardless of the light source. In conclusion, the compressive strength of the tested materials photoactivated with a QTH and a LED light source was influenced by the energy density employed and the chemical composition of the esthetic restorative materials.
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Copaiba oil effect on experimental jaw defect in Wistar rats
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2015-02) SILVA, Priscilla Flores; BRITO, Marcus Vinicius Henriques; PONTES, Flávia Sirotheau Corrêa; RAMOS, Suzana Rodrigues; MENDES, Laís Cordeiro; OLIVEIRA, Louize Caroline Marques
PURPOSE: To evaluate the effects of copaiba oil on jaw defects repair in Wistar rats treated with bioglass or adipose tissue. METHODS: A jaw defect was randomly created in forty-two rats and filled with bioglass or adipose tissue. The two groups (Gbio and Gcell) were subdivided in three subgroups with seven animals each according to gavage administration: control (distillated water), oil (copaiba oil) and melox (meloxicam). Euthanasia was performed after forty post-operative days. The bone formation was analyzed regarding the histological aspects. RESULTS: The osteoclasts activity was observed only in four subgroups (p=0.78). Regarding the osteoblasts presence, it was very similar between the subgroups, the difference was due to Gcell-melox (p=0.009) that presented less osteoblastic activity. The inflammatory cells were more evident in Gcell-melox subgroup, however, there was no difference in comparison with the other subgroups (p=0.52). Bone formation was observed in all subgroups, just two animals showed no bone formation even after 40 days. More than 50% of bone matrix mineralization was observed in 56% (23 animals) of the analyzed areas. The bone matrix mineralization was not different between subgroups (p=0.60). CONCLUSIONS: The subgroups that received copaiba oil showed bone repair, although not statistically significant in comparison to subgroups treated whit meloxicam or controls. Copaiba oil administered by gavage had no effect on bone repair in this experimental model.
Acesso aberto (Open Access)
Cyclic fatigue resistance of rotary niti instruments after simulated clinical use in curved root canals
(2013-04) PESSOA, Oscar Faciola; SILVA, Juliana Melo da; GAVINI, Giulio
The aim of this study was to assess cyclic fatigue resistance in rotary nickel-titanium instruments after simulated clinical use in curved root canals (40-degree, 5-mm radius curve). Thirty-six RaCe rotary NiTi files, size #5, taper 0.04, were divided into 3 groups: Groups A, B and C with one, three and five cycles of use, respectively. Time to failure was recorded with a stopwatch in seconds and subsequently converted to number of cycles to fracture. The data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Five sets of clinically used files (group C) reached significantly lower cycle-numbers before fracture (mean=197.5 cycles) when compared with one set of clinically used files (mean=309.2) and three sets (mean=287.5). Results showed that the number of simulated clinical uses of RaCe instruments for shaping curved canals affects adversely the fatigue resistance of these instruments after five uses.
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.