Upper airway expansion after rapid maxillary expansion evaluated with cone beam computed tomography

Objective: Cone-beam computed tomography (CBCT) is a reliable method of assessing the oral cavity and upper airways. We conducted this study to examine the changes introduced by rapid maxillary expansion in the nasal cavity, nasopharynx, and oropharynx as seen with images obtained by CBCT. Materials and Methods: We evaluated 15 patients with maxillary width deficiency treated with RME. Patients were subjected to CBCT at the beginning of RME and after the retention period of 4 months. Results: The nasal cavity presented a significant transverse increase in the lower third, in the anterior (1.08 mm +/- 0.15), medium (1.28 mm +/- 0.15), and posterior regions (0.77 mm +/- 0.12). No significant change occurred in the nasopharynx in volume (P = .11), median sagittal area (P = .33), or lower axial area (P = .29) resulting from the RME. A significant change was noted in the oropharynx in volume (P = .05), median sagittal area (P = .01), and lower axial area (P = .04) before and immediately after the RME. Conclusions: RME is able to increase the transverse width of the nasal cavity, but it does not have the same effect in the nasopharynx. Changes noted in the oropharynx may be due to the lack of a standardized position of the head and tongue at the time of image acquisition. (Angle Orthod. 2012;82:458-463.)

Craniofacial morphology and sleep apnea in children with obstructed upper airways: Differences between genders

Objective: To correlate sleep apnea with craniofacial characteristics and facial patterns according to gender. Methods: In this prospective survey we studied 77 male and female children (3-12 years old) with an upper airway obstruction due to tonsil and adenoid enlargement. Children with lung problems, neurological disorders and syndromes, obstructive septal deviation, previous orthodontic treatment, orthodontic surgeries or oral surgeries, or obesity were excluded. Patients were subjected to physical examinations, nasal fiberoptic endoscopy, teleradiography for cephalometric analysis, and polysomnography. Methods: Cephalometric analysis included the following skeletal craniofacial measurements: facial axis (FA), facial depth (FD), mandibular plane angle (MP), lower facial height (LFH), mandibular arch (MA), and vertical growth coefficient (VERT) index. Results: The prevalence of sleep apnea was 46.75% with no statistical difference between genders. Among children with obstructive sleep apnea (Apneia Hypopnea Index - AHI >= 1) boys had higher AHI values than girls. A predominance of the dolichofacial pattern (81.9%) was observed. The following skeletal craniofacial measurements correlated with AHI in boys: FD (r(s) = -0.336/p = 0.020), MP (r(s) = 0.486/p = 0.00), and VERT index (r(s) = -0.337/p = 0.019). No correlations between craniofacial measurements and AHI were identified in girls. Conclusions: Craniofacial morphology may influence the severity of sleep apnea in boys but not in girls. (C) 2012 Elsevier B.V. All rights reserved.

Morphometric endoscopic study of the pharynx in patients with sleep apnea

Purpose: The aims of the study were to measure endoscopically the retrolingual pharynx during wakefulness and sleep before and after maxillomandibular advancement surgery and to quantify the changes observed. Materials and Methods: Eighteen patients with mild to severe grade obstructive sleep apnea hypopnea were evaluated during wakefulness while sitting and lying down and during induced sleep in dorsal decubitus while breathing naturally. Images of the retrolingual region of the pharynx were captured with a nasofibroscope and recorded on a DVD using the Sony Vegas 8.0 software (Sony Creative Software, Madison, WI). The images captured in greater and smaller aperture were measured with the Image J software (produced by Wayne Rasband, United States National Institutes of Health, Bethesda, MD) in linear anteroposterior and linear laterolateral areas. A correction factor was then applied to equalize the size of the images and thus compare them to one another. Results: The postoperative dimensions of the pharynx always increased significantly in all measurements compared with the preoperative ones. During induced sleep in dorsal decubitus, there was a greater gain in the area of smaller aperture (201.33%). Conclusions: The proposed method showed that the dimensions of the pharynx always increased significantly after surgery for maxillomandibular advancement, although the gain was not homogeneous in all dimensions and also varied according to state of consciousness. The greatest gain was observed in the area of smaller aperture with the patient in induced sleep, thus reducing the collapse of the pharynx. (C) 2012 Elsevier Inc. All rights reserved.

The Effect of Adenoidectomy or Adenotonsillectomy on Occlusal Features in Mouth-breathing Preschoolers

Purpose: The purpose of this study was to evaluate mouth-breathing and nasal-breathing children prior to surgical intervention and 28 months postoperatively, comparing the occlusal features obtained pre- and postoperatively through orthodontic study costs. Methods: The mouth-breathing (MB) group consists of 33 MB children who underwent surgery and presented a nasal-breathing (NB) pattern after surgery The control group comprised 22 NB children. The orthodontic examinations were accomplished prior to surgery (77) and an average of 28 months postoperatively (T2). Results: At T1, the MB and NB children presented no statistically significant difference in any analyzed occlusal features and measurements. At T2, the MB presented larger overjet comparing to NB children (P<.05). MB and NB groups presented statistically similar results (P>.05) concerning intercanine and intermolor distances, second primary molar terminal plane and canine relationship, overbite, crossbite, and open bite. From T1 to T2, the MB and NB groups showed a statistically significant difference in the molar terminal plane. Conclusion: Neither the breathing pattern nor the surgery had any effect on occlusal features in 3- to 6-year-olds. (Pediatr Dent 2012;34:10842) Received May 14, 2010 vertical bar Last Revision April 11, 2010 vertical bar Accepted April 12, 2010

Comparison of the area of the pharynx during wakefulness and induced sleep in patients with Obstructive Sleep Apnea (OSA)

The study of obstructive sleep apnea (OSA) has received growing attention over the past years since various aspects have not been sufficiently established. Aim: To evaluate, with the use of magnetic resonance imaging (MRI), changes in the area of the pharynx during wakefulness and induced sleep in patients with OSA. Materials and Methods: A prospective study of thirty-two patients with a polysomnographic diagnosis of OSA. All patients were submitted to MR imaging in order to obtain high-definition anatomical sagittal sequences during wakefulness and during sleep induced with Propofol. An area was defined on the sagittal plane in the midline of the pharynx. This region was called pharyngeal midplane (PMP) area. Results: A significant difference in PMP area (mm(2)) was observed between wakefulness and induced sleep in each patient (p < 0.000001). Conclusion: The patients with OSA suffer a significant reduction of 75,5 % in the area of the pharynx during induced sleep compared to wakefulness.

The Extracellular Matrix of the Lateral Pharyngeal Wall in Obstructive Sleep Apnea

Study Objectives: To compare the components of the extracellular matrix in the lateral pharyngeal muscular wall in patients with and without obstructive sleep apnea (OSA). This may help to explain the origin of the increased collapsibility of the pharynx in patients with OSA. Design: Specimens from the superior pharyngeal constrictor muscle, obtained during pharyngeal surgeries, were evaluated using histochemical and immunohistochemical analyses to determine the fractional area of collagen types I and II, elastic fibers, versican, fibronectin, and matrix metalloproteinases 1 and 2 in the endomysium. Setting: Academic tertiary center. Patiens: A total of 51 nonobese adult patients, divided into 38 patients with OSA and 13 nonsnoring control subjects without OSA. Interventions: Postintervention study performed on tissues from patients after elective surgery. Measurements and Results: Pharyngeal muscles of patients with OSA had significantly more collagen type I than pharyngeal muscles in control subjects. Collagen type I was correlated positively and independently with age. The other tested components of the extracellular matrix did not differ significantly between groups. In a logistic regression, an additive effect of both the increase of collagen type I and the increase in age with the presence of OSA was observed (odds ratio (OR), 2.06; 95% confidence interval (CI), 1.17-3.63), when compared with the effect of increased age alone (OR, 1.11; 95% CI, 1.03-1.20). Conclusion: Collagen type I in the superior pharyngeal constrictor muscle was more prevalent in patients with OSA and also increased with age. It was hypothesized that this increase could delay contractile-relaxant responses in the superior pharyngeal constrictor muscle at the expiratory-inspiratory phase transition, thus increasing pharyngeal collapsibility.

Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

Abstract Background Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances. Methods/Design An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow. Discussion Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers.

PALEOPRODUCTIVITY CHANGES DURING THE LATE QUATERNARY IN THE SOUTHEASTERN BRAZILIAN UPPER CONTINENTAL MARGIN OF THE SOUTHWESTERN ATLANTIC

Changes in the Brazilian continental margin`s oceanic productivity and circulation over the last 27,000 years were reconstructed based on sedimentological and microfaunal analyses. Our results suggest that oceanic paleoproductivity and the supply of terrigenous sediments to the Brazilian continental margin were higher during the Last Glacial Maximum (LGM) than during the Holocene. These changes may have been primarily influenced by significant sea level fluctuations that have occurred since the late Pleistocene. During the LGM, the lower sea level, higher productivity and lower sea-surface paleotemperatures may have been the result of the offshore displacement of the main flow of the Brazil Current. However, during the Holocene, the warm waters of the Brazil Current were displaced toward the coast. This displacement contributed to the increase in water temperature and prevented an increase in oceanic productivity. The decrease in terrigenous supply since the LGM could be related to the increase of the extension of the continental shelf and/or drier climatic conditions.

Deep chlorophyll maximum and upper ocean structure interactions: Case of the Guinea Thermal Dome

Deep Chlorophyll Maximum (DCM) modifies the upper ocean heat capture distribution and thus impacts water column temperature and stratification, as well as biogeochemical processes. This energetical role of the DCM is assessed using a 1 m-resolution 1D physical-biogeochemical model of the upper ocean, using climatological forcing conditions of the Guinea Dome (GD). This zone has been chosen among others because a strong and shallow DCM is present all year round. The results show that the DCM warms the seasonal thermocline by +2 degrees C in September/October and causes an increase of heat transfer from below into the mixed layer (ML) by vertical diffusion and entrainment, leading to a ML warming of about 0.3 degrees C in October. In the permanent thermocline, temperature decreases by up to 2 degrees C. The result is a stratification increase of the water column by 0.3 degrees C m(-1) which improves the thermocline realism when compared with observations. At the same time, the heating associated with the DCM is responsible for an increase of nitrate (+300%, 0.024 mu M), chlorophyll (+50%, 0.02 mu g l(-1)) and primary production (+45%: 10 mg C m(-2) day(-1)) in the ML during the entrainment period of October. The considered concentrations are small but this mechanism could be potentially important to give a better explanation of why there is a significant amount of nitrate in the ML. The mechanisms associated with the DCM presence, no matter which temperature or biogeochemical tracers are concerned, are likely to occur in a wide range of tropical or subpolar regions; in these zones a pronounced DCM is present at least episodically at shallow or moderate depths. These results can be generalized to other thermal dome regions where relatively similar physical and biogeochemical structures are encountered. After testing different vertical resolutions (10 m, 5 m, 2.5 m, 1 m and 0.5 m), we show that using at least a 1 to vertical resolution model is mandatory to assess the energetical importance of the DCM.

Benthic foraminiferal distribution on the southeastern Brazilian shelf and upper slope

Foraminiferal data were obtained from 66 samples of box cores on the southeastern Brazilian upper margin (between 23.8A degrees-25.9A degrees S and 42.8A degrees-46.13A degrees W) to evaluate the benthic foraminiferal fauna distribution and its relation to some selected abiotic parameters. We focused on areas with different primary production regimes on the southern Brazilian margin, which is generally considered as an oligotrophic region. The total density (D), richness (R), mean diversity (H) over bar`, average living depth (ALD(X) ) and percentages of specimens of different microhabitats (epifauna, shallow infauna, intermediate infauna and deep infauna) were analyzed. The dominant species identified were Uvigerina spp., Globocassidulina subglobosa, Bulimina marginata, Adercotryma wrighti, Islandiella norcrossi, Rhizammina spp. and Brizalina sp.. We also established a set of mathematical functions for analyzing the vertical foraminiferal distribution patterns, providing a quantitative tool that allows correlating the microfaunal density distributions with abiotic factors. In general, the cores that fit with pure exponential decaying functions were related to the oligotrophic conditions prevalent on the Brazilian margin and to the flow of the Brazilian Current (BC). Different foraminiferal responses were identified in cores located in higher productivity zones, such as the northern and the southern region of the study area, where high percentages of infauna were encountered in these cores, and the functions used to fit these profiles differ appreciably from a pure exponential function, as a response of the significant living fauna in deeper layers of the sediment. One of the main factors supporting the different foraminiferal assemblage responses may be related to the differences in primary productivity of the water column and, consequently, in the estimated carbon flux to the sea floor. Nevertheless, also bottom water velocities, substrate type and water depth need to be considered.

The anatomy of the upper cretaceous snake Najash rionegrina Apesteguia & Zaher, 2006, and the evolution of limblessness in snakes

Najash rionegrina Apesteguia & Zaher, 2006, a terrestrial fossil snake from the Upper Cretaceous of Argentina, represents the first known snake with a sacrum associated with robust, well-developed hind limbs. Najash rionegrina documents an important gap in the evolutionary development towards limblessness, because its phylogenetic affinities suggest that it is the sister group of all modern snakes, including the limbed Tethyan snakes Pachyrhachis, Haasiophis, and Eupodophis. The latter three limbed marine fossil snakes are shown to be more derived morphologically, because they lack a sacrum, but have articulated lymphapophyses, and their appendicular skeleton is enclosed by the rib cage, as in modern snakes.

A new species of Hemigrammus from the upper Rio Tapajos basin in Brazil (Teleostei : Characiformes : Characidae)

Hemigrommus silimoni is described from the Rio Juruena, upper Rio Tapajos basin, Mato Grosso State, Brazil. The new species is distinguished from all congeners, and in fact from the remaining Characidae, by the autapomorphic presence of an ocellus-like blotch on the caudal-fin dorsal lobe. The high level of fish endemicity In the Rio Juruena (upper Rio Tapajos basin) is discussed.

A new distinctively banded species of Pseudolithoxus (Siluriformes: Loricariidae) from the upper Orinoco River

Pseudolithoxus kelsorum is described as a new species based on type material from the upper Orinoco in Amazonas State, Venezuela. Pseudolithoxus kelsorum is diagnosed from all other Pseudolithoxus by having dark brown to black base color with eight to 11 (usually nine) light yellow vertical or oblique transversal bands between orbits and caudal fin, bands wide and rarely but sometimes incomplete or contorted as swirls (vs. dark brown to black base color with 18 or more thin, light yellow, frequently contorted transversal bands between orbits and caudal fin in P. tigris; black base color with small white spots in P. anthrax and P. nicoi; and light brown base color with dark brown to black spots in P. dumus). Distributions of P. kelsorum and other Ancistrini taxa support the presence of a zoogeographic filter limiting fish distributions across a reach of the Orinoco River between the Ventuari-Orinoco confluence and the Maipures rapids.