Snoring Remediation with Oral Appliance Therapy Potentially Reverses Cognitive Impairment: An Intervention Controlled Pilot Study.

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.

Objective and subjective image evaluation of maxillary alveolar bone based on cone beam computed tomography exposure parameters.

OBJECTIVES: The purpose of this study was to optimize the exposure parameters for cone beam computed tomography (CBCT) for performing diagnostic imaging of maxillary alveolar bone. STUDY DESIGN: CBCT (Promax 3 D Max) was performed on a frozen human cadaver head. Image homogeneity and the degree of alveolar bone contrast were determined by objective assessment using ImageJ software and subjective assessment by orthodontists and oral radiologists. Kruskal-Wallis tests and interrater agreement were used to compare results across groups. RESULTS: Image homogeneity and degree of alveolar bone contrast differed significantly among all exposure protocols (P < .001). Intraclass correlation values ranged from 0.681 to 0.779, with orthodontists having higher values compared with oral radiologists. Average of image quality scores between protocols were statistically significant (P < .001) and ranged from "fair" to "good." CONCLUSIONS: There is great potential to reduce CBCT radiation doses for maxillary alveolar bone while maintaining adequate image quality for diagnosis.

Improving the Evaluation of Alveolar Bone Grafts With Cone Beam Computerized Tomography.

OBJECTIVE: Cone Beam computed tomography (CBCT) is used increasingly as a replacement for periapical x-rays when evaluating alveolar bone grafting. The manufacturer's standard settings for dental imaging may not, however, represent the optimal settings for evaluating postoperative alveolar bone grafts. We examined the influence of exposure parameters on CBCT image quality to optimize the quality of CBCT images while reducing the radiation dose to the minimum level necessary to obtain adequate images. METHODS: A defect was created in a cadaver head to simulate an alveolar cleft, and the area was filled with a synthetic material to simulate an alveolar bone graft. Serial CBCT scans were acquired, systematically varying tube voltage and tube current settings from 72 to 96kV and 3 to 12mA. Region of interest analysis was undertaken, and image quality was evaluated by comparing the ratios of native alveolar bone to soft tissue and the ratios of synthetic bone graft to soft tissue and by assessing image noise. RESULTS: Twenty-one CBCT data sets were obtained. Reducing tube voltage (kV) resulted in increased contrast ratio between bone and soft tissue and between synthetic bone graft and soft tissue, with maximal contrast at values of 76 kV/11 mA, 72 kV/12 mA, and 72 kV/11 mA. Of these, the setting with lowest image noise was 76 kV/11 mA. This setting also resulted in a radiation dose of less than half of the manufacturer's recommended settings for the same scan volume. CONCLUSIONS: There is potential to improve CBCT image quality significantly while dramatically reducing the radiation dose during postoperative examinations for alveolar bone grafting in patients with cleft lip and palate.

Orthodontic considerations for maxillary distraction osteogenesis in growing patients with cleft lip and palate using internal distractors.

The orthodontist plays a key role in the selection of the optimal treatment for patients followed by a craniofacial team. For patients with cleft lip and palate, the need for multidisciplinary treatment planning and sequentially staged treatment is essential for successful patient outcomes. The technique of Le Fort I distraction osteogenesis of the maxilla using an internal device is potentially a predictable, stable, and convenient option for the correction of severe maxillary hypoplasia. It is an alternative option for treatment of maxillary hypoplasia in growing patients. In this article, the authors describe the orthodontist's approach to the management of cleft patients with severe maxillary deficiency with the use of an internal distraction device. The information is presented with a focus on the clinical aspects of treatment, using case illustrations and appropriate literature.

Image assessment of MSCT and CBCT scans for rapid maxillary expansion: a pilot study.

OBJECTIVES: The accuracy of cone-beam technique, cone-beam computed tomography (CBCT), compared with that of the multislice spiral CT (MSCT), for image-based linear measurements of midpalatal suture was assessed. MATERIAL AND METHODS: Two measurements were performed by one investigator on the dry skull by using one digital caliper and in the axial cuts by using software. A 2D object-based image registration process was applied to determine the best affine transformation that maps a 2D input image (CBCT) in a reference image (MSCT). RESULTS: The value of the intraclass correlation coefficient was approximately 0.9%. The results suggest that differences between two scanners did not exist (observation 1, p = 0.964 and observation 2, p = 0.795). With regard to the dry skull and the image, the significance probabilities equaled zero (observation 1, p = 0.002 and observation 2, p = 0.004), therefore, indicating significant differences. CONCLUSION: Measurements acquired in the images were similar and these findings contribute to stimulate the use of CBCT for evaluation of the maxillary expansion procedure.

Influence of enamel sandblasting prior to etching on shear bond strength of indirectly bonded lingual appliances.

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 µm 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 = .048). However, the log-rank test demonstrated that clinical performance of the groups evaluated was not significantly different (P = .091). The adhesive remnant index (ARI) was significantly higher when using sandblasting prior to acid etching than in the control group (P = .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.

Expansão rápida da maxila: avaliação de dois métodos de reconstrução 3D por meio de um modelo laboratorial / Rapid maxillary expansion: evaluation of two methods of 3D reconstruction by means of a laboratorial model

OBJETIVO: a proposta deste artigo é apresentar um modelo laboratorial para aquisição de imagens tomográficas para avaliação tridimensional do procedimento de expansão rápida da maxila (ERM). MÉTODOS: o procedimento de expansão rápida da maxila foi realizado em crânio seco e os exames foram executados em tomógrafo de alta resolução e em tomógrafo de feixe cônico, antes e depois da ERM. RESULTADOS: as imagens obtidas a partir do crânio seco, tomografia computadorizada multislice (TC) e tomografia volumétrica (CBCT) produziram resultados semelhantes para avaliação da abertura da sutura palatina mediana. CONCLUSÃO: a utilização de cortes tomográficos, adquiridos tanto por meio de tomógrafo computadorizado de alta resolução quanto por meio da técnica cone beam, possibilitou a reconstrução 3D da maxila com objetivo de oferecer a real avaliação da abertura intermaxilar.

OBJECTIVE: This paper proposes to present a laboratorial model for acquisition of tomographic images for three-dimensional evaluation of the rapid maxillary expansion procedure. METHODS: The procedure of rapid maxillary expansion was developed using a dry skull and the images were acquired from a multi-slice tomography and a volumetric tomography. The examinations were taken prior to and after the ERM. RESULTS: The images acquired from the skull, multislice computed tomography (CT) and cone beam computed tomography (CBCT) had produced similar results. CONCLUSION: The use of tomographic slices, acquired by means of high resolution computerized tomography, as well as the cone beam technique, make possible the three-dimensional reconstruction of the palatomaxillary region in order to offer the real evaluation of the sutural opening.

Tratamento da má oclusão de Classe II de Angle em duas fases: avaliação da efetividade e eficácia por meio do índice PAR / Two phase treatment of Angle Class II: effectiveness and efficacy evaluation using the PAR index

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 por cento e 85 por cento 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.

The aim of the present study was to compare orthodontic treatment results of Class II division 1 patients treated in one or two phases (early treatment). The sample was randomly composed by 72 Class II patients (31 males and 41 female), treated by six private orthodontists. The observed mean age was 12 (sd = 2.47) and 9.62 years old (sd= 1.51), respectively for the one phase (n=36) and the two phase treatment group (n=36). The mean initial cephalometric and PAR index values for both study groups were compared using the Student t-test, with no significant difference between them, demonstrating initial severity equivalence of the cases. The final orthodontic evaluation was done by only one calibrated operator, using the PAR index (Peer Assessment Rating) on study models. Results didn't show any statistical differences among the groups (p=0.647), with mean PAR reduction rate evaluated in 83 percent and 85 percent for one and two phase group respectively. The mean treatment time was 43.1 months for the two phase and 35 months for the one phase group (statistically significant, p=0,0158). The more severe was the case, the longer they would take to be finished, but no correlation was found between the duration of intervention, patient gender with the final quality result. Although the present study failed to show significant differences between mean orthodontic results, further studies should be carried in order to identify more accurately which are the patients that would really benefit from class II early treatment.

A técnica do arco reto em ortodontia lingual com o uso do PW-MBP / Straight-wire concepts in lingual orthodontics by using PW-MBP

A Ortodontia Lingual representa uma importante opção para tratamento de pacientes adultos. Apesar de todos os avanços concernentes a braquetes e fios, bons resultados dificilmente são obtidos sem um criterioso posicionamento dos braquetes. Um dos recursos disponíveis para montagem é o "Plain Wire Mushroom Bracket Positioner" (PW-MBP), que permite o uso de arcos parabólicos durante o tratamento, eliminando a necessidade de dobras entre os caninos e pré-molares