Ivana Uglik Garbui

Qualitative and quantitative evaluation of human dental enamel after bracket debonding: a noncontact three-dimensional optical profilometry analysis

ObjectivesThe aim of this study was to undertake a qualitative and quantitative evaluation of changes on enamel surfaces after debonding of brackets followed by finishing procedures, using a high-resolution three-dimensional optical profiler and to investigate the accuracy of the technique.Materials and methodsThe labial surfaces of 36 extracted upper central incisors were examined. Before bonding, the enamel surfaces were subjected to profilometry, recording four amplitude parameters. Brackets were then bonded using two types of light-cured orthodontic adhesive: composite resin and resin-modified glass ionomer cement. Finishing was performed by three different methods: pumice on a rubber cup, fine and ultrafine aluminum oxide discs, and microfine diamond cups followed by silicon carbide brushes. The samples were subsequently re-analyzed by profilometry.ResultsWilcoxon signed-rank test, Kruskal–Wallis test (p < 0.05) and a posteriori Mann–Whitney U test with Bonferroni correction (p < 0.0167) revealed a significant reduction of enamel roughness when diamond cups followed by silicon carbide brushes were used to finish surfaces that had remnants of resin-modified glass ionomer adhesive and when pumice was used to finish surfaces that had traces of composite resin. Enamel loss was minimal.ConclusionsThe 3D optical profilometry technique was able to provide accurate qualitative and quantitative assessment of changes on the enamel surface after debonding.Clinical relevanceMorphological changes in the topography of dental surfaces, especially if related to enamel loss and roughness, are of considerable clinical importance. The quantitative evaluation method used herein enables a more comprehensive understanding of the effects of orthodontic bonding on teeth.

Craniofacial analysis of the Tweed Foundation in Angle Class II, division 1 malocclusion

This study has defined the cephalometric values of the Craniofacial Analysis of the Tweed Foundation for a sample of Brazilian subjects. The sample consisted of 211 cephalometric radiographs from subjects aged 12-15, which were divided into two groups: Class II group, with 168 lateral teleradiographs (cephalograms) of white Brazilian subjects, with Angle Class II, division 1 malocclusion, of both genders (82 males and 86 females); and the Control Group, with 43 lateral teleradiographs (cephalograms) of subjects whose occlusion was clinically excellent, and also of both genders (21 males and 22 females). The teleradiographs were selected from the files of the Department of Orthodontics, School of Dentistry of Piracicaba, State University of Campinas, previously to the orthodontic treatment. The results demonstrated no sexual dimorphism for each group, as attested by the Students t-test. The exploratory analysis (+/- 0.5 standard deviation) enabled the tolerance limits to be determined and a Craniofacial Analysis Table to be constructed using the respective cephalometric intervals. In addition, the difference between the two groups was not statistically significant according to the maxilla position. The maxilla was in a good position in relation to the cranial base. On the other hand, the mandible was retruded in relation to the cranial base in the Class II cases. The skeletal pattern was not defined because only the Facial Height Index (FHI) showed a vertical pattern in Class II subjects, while the Y Axis, SN.PlO, SN.GoMe and FMA values did not show any statistically significant difference between the groups. The Class II division 1 subjects showed lower incisors more labially tipped and a convex facial profile.

Cephalometric assessment of vertical control in the treatment of class II malocclusion with a combined maxillary splint

Vertical control is one of the primary objectives sought by orthodontists when treating malocclusions in hyperdivergent individuals. This investigation aimed at assessing vertical control, by cephalometric measurements, during the treatment of Angle Class II Division 1 malocclusion. Thirty cases, selected from the files of the São Leopoldo Mandic Dental Research Center, Brazil, of subjects with Angle Class II Division 1 malocclusion and facial hyperdivergence, were used in this study. The patients were treated using a combined extraoral appliance during a mean treatment time of 1.1 years. Pre- and posttreatment cephalometric measurements were compared to assess vertical control. The results were submitted to ANOVA (p = 5%). The ANOVA test revealed no statistically significant difference between the pretreatment and posttreatment values of OP (Occlusal plane angle) and SN.MP. While there was a decrease in Y-axis, FMA, and PP.MP, there was an increase in SN.PP, Co-Go, AFH, PFH, and FHI. It was concluded that the divergence in the facial lower third of the patients did not increase, suggesting that the combined extraoral appliance with the line of force application directed to the resistance center of the maxilla was effective in treating Angle Class II malocclusion in hyperdivergent subjects.

Comparação entre análises de referência incisal em indivíduos jovens melanodermas brasileiros com oclusão normal

Defining the position for the mandibular incisor provides data for a correct treatment planning and treatment itself, in order to achieving a better stability after retention. However, it has been observed that cephalometric analyses that are usually employed in orthodontics for diagnosis are based on studies on caucasians, whose craniofacial characteristics differ from those of other races. Thus, the present study aims to investigate the behavior of mandibular incisor related to incisal landmarks that are commended by Andrade (1-Jr), Interlandi (1- I line), Vigorito (1- V line) and Ricketts (1- APo line), in african-american children with normal occlusion, and to verify the occurrence of sexual dimorphism. Thirty-six lateral skull films from african-american subjects were selected from the FOP/UNICAMP Department of Orthodontics Post-Graduation Program Scientific Recordings; the patients ages varied from 10 to 14 years, and they presented clinically excellent occlusion, and have not undergone orthodontic treatment. The cefalogram required for the suggested analyses were drawed. The presented values for the mandibular incisor position differ among themselves as by two different statistical analysis; there is also significant difference among the referred methods. No sexual dimorphism was found in this study. It was shown that the position of mandibular incisor of african-american children presented greater labioversion than the same parameters as commended by the proposed authors, and that Andrade analysis seemed more adequate to this ethnic group.

Effect of etching time and light sources on the shear bond strength of metal brackets to ceramic cylinders

OBJECTIVE: To evaluate the shear bond strength of brackets bonded to ceramic with Transbond XT resin, etching time intervals (1 and 2 minutes) and three Light sources (Xenon Plasma Arc, LED and Halogen Light ), with and without silane.METHODS: In total, 12 feldspathic ceramic cylinders (15 mm x 20 mm), etched with 10% hydrofluoric acid were used. For light activation, the brackets were divided according to the light source to be used (n-15): LED UltraLume 5 (L); Apollo 95E plasma arc (AP) and Halogen light XL 2500 (H). After 24 h the samples were submitted to shear bond strength testing at crosshead speed of 0.5 mm/minute.RESULTS: The data were submitted to the analysis of variance (ANOVA) and the Tukey test (5%). Bond Strength: UltraLume 5 (11.4 ± 3.56 MPa) was superior to XL 2500 (9.12 ± 2.83 MPa) and Plasma Arc (5.11 ± 2.93 MPa) (p<0.05). No difference was found between ceramic with silane (8.31 ± 4.17 MPa) and without silane (8.68 ± 3.86 MPa). Etching time of 2 minutes (9.13 ± 3.98 MPa) was superior to time of 1 minute (7.86 ± 3.96 MPa).CONCLUSION: The results showed that LED was shown to be more efficient for polymerizing the material for Transbond XT bonding. The use of silane did not influence the bond strength values. The acid etching time of 2 minutes was more effective than that of 1 minute.

Wylie-Johnson analysis of adolescents of Afro-Brazilian descent with normal occlusion: investigation of the mean values

OBJECTIVE: The purpose of this study was to evaluate mean cephalometric measurements for a group of individuals of Afro-Brazilian descent using the Wylie-Johnson analysis, and to investigate the presence of sexual dimorphism.METHODS: Thirty-six lateral radiographs of the head of African-Brazilians were used. Subjects were 10 to 14 years old and had clinically normal occlusion, all permanent teeth, and no history of orthodontic treatment.RESULTS: Results for girls and boys were, respectively: SNA 88.31o and 89.68o; SNB 83.96o and 85.01o; ANB 4.44o and 4.69o; 1:1= 118.18o and 116.51o; FG-ST 16.47 mm and 16.12 mm; ST-Pmf 19.69 mm and 19.88 mm; Pmf-ANS 53.69 mm and 54.84 mm; Pmf-1oMS 21.83 mm and 20.64 mm; FG-Pg 108.19 mm and 108.45 mm; FPL -MPL 27.48o and 27.65o; TAFH 111.06 mm and 112.26 mm; UAFH 45.26 mm and 45.38 mm; LAFH 65.80 mm and 66.88 mm; FG-FPL 1.069 mm and -2.086 mm; MBL 70.24 mm and 69.67 mm; MRH 51.89 mm and 53.70 mm; gonial angle 129.27o and 129.28o. Results of Students-t test (α=5%) did not show any sexual dimorphism. Results of descriptive statistics were similar for the individuals of Afro-Brazilian descent in the study.CONCLUSION: Individuals of African descent had bimaxillary protrusion, a more acute interincisal angle, a larger inferior facial height, and a markedly convex profile.

Avaliação da idade óssea em crianças de 9 a 12 anos de idade na cidade de Manaus-AM

OBJETIVO: o presente estudo teve como objetivo avaliar a idade ossea pelo metodo de Greulich & Pyle (1959) e o periodo do crescimento puberal, de acordo com o trabalho de Martins (1979). METODOS: utilizaram-se radiografias de mao e punho de 201 criancas amazonenses, sendo 103 do sexo masculino e 98 do feminino, com idades cronologicas de 9 a 12 anos. Para analise estatistica, utilizou-se o teste de qui-quadrado com nivel de significância em 5% (p<0,05). RESULTADOS E CONCLUSOES: as criancas do sexo feminino, em relacao as do sexo masculino, encontravam-se mais adiantadas em todas as fases do crescimento esqueletico, para as idades estudadas, estando 50% das meninas no pico do crescimento puberal, enquanto apenas 11,6% dos meninos estavam na mesma fase. As idades do inicio e pico do surto de crescimento puberal foram mais precoces nas meninas (10,1±0,7 e 11,1±0,8 anos, respectivamente) do que nos meninos (11,4±0,7 e 12,3±0,4 anos, respectivamente). As meninas apresentaram uma maior porcentagem de maturacao precoce do que os meninos (41,8% e 5,8%, respectivamente); enquanto a maturacao tardia foi mais prevalente nos meninos (38,8%) do que nas meninas (11,2%). A idade ossea media dos meninos foi de 10,4±1,7 anos e das meninas, 11,7±1,8 anos, para o grupo estudado.