Navegando por Autor "ALMEIDA, Haroldo Amorim de"

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Acesso aberto (Open Access)
Avaliação cefalométrica do perfil tegumentar e esquelético inicial e final de tratamento ortodôntico
(Universidade Estadual de Campinas, 1999-07-06) ALMEIDA, Haroldo Amorim de; ALMEIDA, Maria Helena Castro de; http://lattes.cnpq.br/0770202080280415
Was accomplished a study in 114 telerradiography of the head in lateral norm, of 57 Brazilian individuais, white, with Class 11, division 1 malocclusion (An.gle), submitted to orthodontic treatment according to the Tweed philosophy, with the purpose of evaluating the alterations to levei of the bony and soft-profile . The results demonstrated that among the angle Z and FMA an inverse correlation exists; when modifying the values of FMIA, Âng. Z suffers alterations of same degree and direction; altering the angle of the occlusal plan, they happen variations of similar value in FMA; any modification in ANB is accomplished by an alteration in AO-BO, of same magnitude and direction.
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)
In vitro analysis of shear bond strength and adhesive remnant index comparing light curing and self-curing composites
(2013) NEVES, Murilo Gaby; BRANDÃO, Gustavo Antônio Martins; ALMEIDA, Haroldo Amorim de; BRANDÃO, Ana Maria Martins; AZEVEDO, Dário Ribeiro de
OBJECTIVE: To evaluate, in vitro, the shear bond strength of self-curing (ConciseTm - 3M and Alpha Plast - DFL) and light-curing composites (TransbondTM XT - 3M and Natural Ortho - DFL) used in orthodontics bonding, associated to Morelli metal brackets, with further analysis of adhesive remnant index (ARI) and enamel condition in scanning electron microscopy (SEM). METHODS: Forty human premolars, just extracted and stored in physiologic solution 0.9 % were used. Randomly, these samples were divided in four groups: G1 group, the brackets were bonded with ConciseTM - 3M composite; in G2 group, Alpha Plast - DFL composite was used; in G3 group, TransbondTM XT - 3M was used; in G4 group, Natural Ortho - DFL composite was used. These groups were submitted to shear strength tests in universal testing machine, at 0.5 mm per minute speed. RESULTS: Statistical difference between G3 and G4 groups was recorded, as G4 showing higher strength resistance than G3. In the other hand, there were no statistical differences between G1, G2 and G3 and G1, G2 and G4 groups. ARI analysis showed that there was no statistical difference between the groups, and low scores were recorded among then. The scanning electron microscopy (SEM) analysis revealed the debonding spots and the enamel surface integrity. CONCLUSIONS: Shear bond strength was satisfactory and similar between the composites, however Natural Ortho - DFL revealed best comparing to TransbondTM XT - 3M.
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.