Objective: To test the null hypothesis was that there is no difference in the mean shear bond strength of indirectly bonded lingual brackets prepared with or without sandblasting prior to acid etching. Materials and Methods: Forty extracted human premolars were obtained and randomly divided into two groups of 20 each: group I (control), phosphoric acid and indirect bonding with Maximum Cure and Phase II (Reliance, Itasca, Ill); and group II, sandblasting with 50 mm aluminum oxide (Microetcher, Danville Engineering, Danville, Calif) prior to etching and indirect bonding. All products were used according to the manufacturer's instructions. Instron universal testing machine was used to apply an occlusogingival shear force directly onto the enamel-bracket interface at a speed of 0.5 mm/min. The groups were compared using unpaired Student's t-test. Kaplan-Meir survival plots and log-rank test were done to compare the survival distribution between the two groups. Results: Mean (SD) shear bond strength for group I was 13.17 (4.33) MPa and for the group II was 16.42 (5.41) MPa. Significant difference was observed in the bond strengths of the two groups evaluated (P 5 .048). However, the log-rank test demonstrated that clinical performance of the groups evaluated was not significantly different (P 5 .091). The adhesive remnant index (ARI) was significantly higher when using sandblasting prior to acid etching than in the control group (P 5 .011). Conclusions: Intraoral sandblasting prior to enamel etching increased the bond strength of lingual brackets, but the clinical performance of the groups was not significantly different. (Angle Orthod. 2011;81:149-152.)

Measurements acquired in the images were similar and these findings contribute to stimulate the use of CBCT for evaluation of the maxillary expansion procedure.

No abstract

Respiration rate (RR) dynamics entrains brain neural networks. RR differences between mild cognitive impairment (MCI) and Alzheimer’s disease (AD) in response to oral appliance therapy (OAT) are unknown. This pilot study investigated if RR during stable sleep shows a relationship to pathological severity in subjects with MCI and AD who snore and if RR is influenced following stabilization of the upper airway using OAT. The study cohort was as follows: cognitively normal (CN; n = 14), MCI (n = 14) and AD (n = 9); and a sub-population receiving intervention, CN (n = 5), MCI (n = 7), AD (n = 6) subjects. The intervention used was an oral appliance plus a mouth shield (Tx). RR maximum (max) rate (breaths/minute) and RR fluctuation during 2116 stable sleep periods were measured. The Montreal cognitive assessment (MoCA) was administered before and after 4 weeks with Tx. Baseline data showed significantly higher RR fluctuation in CN vs. AD (p < 0.001) but not between CN vs. MCI (p = 0.668). Linear mixed model analysis indicated Tx effect (p = 0.008) for RR max. Tx after 4 weeks lowered the RR-max in MCI (p = 0.022) and AD (p < 0.001). Compared with AD RR max, CN (p < 0.001) and MCI (p < 0.001) were higher with Tx after 4 weeks. Some MCI and AD subjects improved executive and memory function after 4 weeks of Tx.

OBJETIVO: Do presente estudo foi comparar o resultado do tratamento ortodôntico de pacientes portadores de má oclusão classe II, divisão 1 tratados em uma e em duas fases (tratamento precoce). METODOLOGIA: A amostra final foi constituída de forma aleatória por 72 pacientes portadores de Classe II (31 do gênero masculino e 41 do gênero feminino), tratados por seis ortodontistas da rede privada. A idade média observada foi de 11,8 (dp=2,5) e 9,58 (dp=1,6) anos para os grupos de uma (n=36) e duas fases (n=36), respectivamente. RESULTADOS: As médias dos valores cefalométricos iniciais e do valor inicial do Índice de Avaliação entre Pares ou Peer Assessment Rating (PAR) nos dois grupos foram comparados pelo teste t-Student, não havendo diferença significativa entre eles, comprovando-se sua equivalência inicial com relação à gravidade dos casos. O resultado do tratamento foi avaliado aplicando-se o PAR aos modelos de estudo iniciais e finais dos pacientes entre os grupos (p=0,647), sendo encontrada uma redução média do índice de 83% e 85% para o grupo de uma e duas fases, respectivamente. A média de duração de tratamento total foi de 43,1 meses para o grupo de duas fases e de 35 meses para o grupo de uma fase, sendo a diferença entre eles significativa (p=0,0158). CONCLUSÕES: A correlação entre o tempo de tratamento e a gravidade inicial do caso foi baixa, porém positiva, contudo, não foi encontrada relação entre o gênero do paciente e a duração da intervenção, com a qualidade final da mesma. Apesar do presente estudo não ter identificado diferenças significativas entre resultados médios, futuros trabalhos deveriam ter como objetivo identificar, com mais exatidão, quais os tipos de pacientes a serem de fato beneficiados por um tratamento precoce.