Obstructive Sleep Apnea Syndrome (OSAS). Review of the literature

Obstructive sleep apnea and hypopnea syndrome is characterized by repeated airway collapse during sleep. The literature describes multiple causes of the disease. The main cause is a reduction of the expansion forces of the pharyngeal dilator muscles, as in situations of genioglossal muscle dysfunction, and discoordination between the inspiratory activity of the muscle and respiratory effort, which play an important role in progression of the disease. Other described causes are soft tissue disorders, such as macroglossia or tonsillar hypertrophy, and skeletal structural alterations such as micrognathia and retrognathia. The syndrome is also more frequent in obese people, where the accumulation of fat in the neck region produces narrowing of th pharyngeal airway, thereby diminishing the passage of air. This review focuses on the pathogenesis, epidemiology, main features and diagnosis of the disease, and on its main forms of treatment

Obstructive sleep apnea syndrome (OSAS): review of the literature

Obstructive sleep apnea and hypopnea syndrome is characterized by repeated airway collapse during sleep. The literature describes multiple causes of the disease. The main cause is a reduction of the expansion forces of the pharyngeal dilator muscles, as in situations of genioglossal muscle dysfunction, and discoordination between the inspiratory activity of the muscle and respiratory effort, which play an important role in progression of the disease. Other described causes are soft tissue disorders, such as macroglossia or tonsillar hypertrophy, and skeletal structural alterations such as micrognathia and retrognathia. The syndrome is also more frequent in obese people, where the accumulation of fat in the neck region produces narrowing of the pharyngeal airway, thereby diminishing the passage of air. This review focuses on the pathogenesis, epidemiology, main features and diagnosis of the disease, and on its main forms of treatment

True vertical validation in facial orthognathic surgery planning

Objectives: To validate the effectiveness of the original standards of True Vertical (TV) Subnasal Line in orthognatic surgery planning. The present study evaluates the changes occurring in patients with skeletal Class II alterations programmed for orthognathic surgery with a view to improving their facial profile. Study desing: We showed a series of black profiles (composed by a first control group of subjects with normal occlusion, and another two additional groups comprised patients before -Group 2- and after orthognatic surgical correction of Class II malocclusion -Group 3-) for three groups of observers (orthodontists, surgeons and laypeople). The facial images became black silhouettes in order to determine a series of parameters (including aesthetic assessment) by means of the observers. Their observation were assessed using a 5-point Likert scale. Results: The sample was composed of 52 profile's subjects who were tested for a total of 72 observers. Aesthetic assessment yielded mean scores of 2.57, 1.67 and 2.46 for groups 1, 2 and 3, respectively. There was a statistically significant difference (p<0.001) between group 1 versus group 2. There were no significant differences in terms of observer assessment of aesthetics, with the exception of a wider perception range among the orthodontists. Regarding the studied profile measures, significant differences were recorded for point B' and Pg' (p<0.02) between groups 2 and 3 (i.e., pre- versus post-surgery). Conclusions: The results of our study suggest the subnasale vertical and sagittal measures of the lower third of the face are decisive in facial aesthetics, and therefore also for the planning of orthognathic surgery. Consequently, these aesthetic parameters can be used as an objective tool for the planning of orthodontic treatment

Class II subdivision : cone beam computed tomography- CBCT Analysis

To estimate whether there is skeletal and/or dental asymmetry in class II subdivision patients, between the Class II side and the Class I side using of cone beam computed tomography (CBCT). A sample of 30 patients, from a private clinic, retrospectivel

Lower incisor position in different malocclusions and facial patterns

Introduction: The position of lower incisor has been of considerable concern when planning an orthodontic treatment, having been recognized as one of diagnostic keys, Very important in the development of malocclusion and facial pattern. Objectives: In this study we claim to determine the importance of the position and inclination of lower incisor in the different malocclusions and facial patterns, and to base which of the cephalometric measurement parameters are the mostreliable. Material and Methods: Ninety lateral radiographies were taken, and they were classified by skeletal malocclusion and facial pattern.These teleradiographies have been performed cephalometric analysis, which includelower incisor position belong the following analysis: Ricketts, Riolo, Tweed, McHorris, Jarabak-MSE and Holdaway. Study Design: Cross-sectional study where we perform statistical analysis Anova test, Pearson correlations and Bonferroni analysis. Results: The analyzed measurements present a statistically significant differentiation in lower incisor inclination respect to the anterior cranial base, McHorris angle, angulation of lower incisor respect to occlusal plane and mandibular plane. Conclusions: There are statistically significant differentiation in lower incisor position and inclination respect the malocclusion and individual facial pattern

Effect of temperature on the orthodontic clinical applications of niti closed-coil springs

NiTi spring coils were used to obtain large deformation under a constant force. The device consists on a NiTi coil spring, superelastic at body temperature, in order to have a stress plateau during the austenitic retransformation during the unloading. The temperature variations induced changes in the spring force. Objectives: The aim of this study is to investigate the effect of the temperature variations in the spring forces and corrosion behaviour simulating the ingestion hot/cold drinks and food. Study D esign: The springs were subjected to a tensile force using universal testing machine MTS-Adamel (100 N load cell). All tests were performed in artificial saliva maintained at different temperatures. The corrosion tests were performed according to the ISO-standard 10993-15:2000. Results: The increase in temperature of 18 o C induced an increase in the spring force of 30%. However, when the temperature returns to 37 o C the distraction force recovers near the initial level. After cooling down the spring to 15 o C, the force decreased by 46%. This investigation show as the temperature increase, the corrosion potential shifts towards negative values and the corrosion density is rising. Conclusions: The changes of the temperatures do not modify the superelastic behaviour of the NiTi closed-coil springs. The corrosion potential of NiTi in artificial saliva is decreasing by the rise of the temperatures

Lower incisor position in different malocclusions and facial patter

Introduction: The position of lower incisor has been of considerable concern when planning an orthodontic treatment, having been recognized as one of diagnostic keys, Very important in the development of malocclusion and facial pattern. Objectives: In this study we claim to determine the importance of the position and inclination of lower incisor in the different malocclusions and facial patterns, and to base which of the cephalometric measurement parameters are the mostreliable. Material and Methods: Ninety lateral radiographies were taken, and they were classified by skeletal malocclusion and facial pattern.These teleradiographies have been performed cephalometric analysis, which includelower incisor position belong the following analysis: Ricketts, Riolo, Tweed, McHorris, Jarabak-MSE and Holdaway. Study Design: Cross-sectional study where we perform statistical analysis Anova test, Pearson correlations and Bonferroni analysis. Results: The analyzed measurements present a statistically significant differentiation in lower incisor inclination respect to the anterior cranial base, McHorris angle, angulation of lower incisor respect to occlusal plane and mandibular plane. Conclusions: There are statistically significant differentiation in lower incisor position and inclination respect the malocclusion and individual facial pattern

Wilson maxillary curve analyzed by cbct a study on normocclusion and malocclusion individuals

The anatomy of dental compensation curve in the frontal plane described by George H. Wilson is one of the occlusal determinants of orthodontic treatment. However, there is few published comparing malocclusion and normocclusion individuals. Objectives: The aim of this study is to compare the curve of Wilson at first and second maxillary molars, normocclusion pattern and malocclusion pattern, with and without bilateral posterior crossbite, using angular references in CBCT studies. Material and Methods: We analyzed 10 cases of malocclusion with bilateral posterior crossbite, 10 cases of malocclusion without bilateral posterior crossbite and 10 cases with non orthodontic normocclusion (patients who underwent cone beam study for other reasons than orthodontic). All of them were adults, more than 19 years. Angular variables from left and right axis (line connecting the occlusal and furcation groove) of first and second molars towards a perpendicular to the frontal palate were measured. There was carried out an Anova test, Bonferroni analysis and Levene's statistics. Results: The descriptive analysis of the results shows an average values of total maxillary curve of Wilson for first molars (sum of left and right angle) of 8.1° for normocclusion group, 0.4° for the malocclusion pattern with bilateral posterior crossbite and 16.9° for the malocclusion pattern without this alteration. The mean differences was statistical significant (P<0,042) between between malocclusion pattern groups with and without crossbite . Conclusion: The curve of Wilson, measured at maxillary first molars in patients with bilateral posterior crossbite is more concave than the other groups, suggesting no dentoalveolar compensations

Comparison of condylar position in normal occlusion, Class II Division 1, Class II Division 2 and Class III malocclusions using CBCT imaging

The aim of this study was to establish the condylar position in a group of patients with normal occlusion, compared to Class II Div 1, Class II Div 2 and Class III malocclusions using CBCT imaging. Retrospective case-control study carried out by analyz

Propagation and in vitro tuberization of two varieties of potato

1 recurso en línea (páginas 21-31).La investigación se realizó en el Laboratorio de Cultivo de Tejidos Vegetales de la Universidad Pedagógica y Tecnológica de Colombia con el propósito de conocer el comportamiento in vitro y evaluar una metodología para propagación de plántulas y producción de microtubérculos de dos variedades de papa (Solanum tuberosum L. ssp andígena) Diacol Capiro y Parda Pastusa, a partir de segmentos nodales obtenidos de tubérculos suministrados por el ICA, desinfectados con NaOCl al 10 %, multiplicados en medio MS y MS+ANA (0.02 mg L-1) y enraizados con ANA o AIB adicionados al medio de cultivo o aplicados en pulsos de 30 segundos. Posteriormente, segmentos uninodales micropropagados se cultivaron en medio para tuberización, observándose una mayor producción en MS suplementado con 2.5 mg L-1 de BA y 8 % de sacarosa en las dos variedades. Los protocolos desarrollados en el presente estudio permitieron la obtención masiva de plántulas y la producción de microtubérculos de Diacol Capiro y Parda Pastusa; las plántulas y microtubérculos desarrollados pueden ser cultivados bajo condiciones controladas para la producción de semilla pre-básica.This study was conducted in the Laboratorio de Cultivo de Tejidos Vegetales of the Universidad Pedagógica y Tecnológica de Colombia with the purpose of acquiring knowledge on the behavior under in vitro conditions as to evaluate a methodology for the micropropagation of plantlets and the production of microtubers from two varieties of potato (Solanum tuberosum L. ssp andigena) Diacol Capiro and Parda Pastusa. The nodal segments provided by the ICA were disinfected with 10 % NaOCl, Then cultured for multiplication in MS medium and MS+NAA (0.02 mg L-1). For the rooting process, NAA or IBA was added into the culture medium or applied in 30 seconds pulses. Subsequently, micropropagated uninodal segments were cultured in tuberization medium, showing an increase in production when supplemented with BA (2.5 mg L-1) and with 8 % saccharose in the two varieties. The protocols developed in this study allow a large number of micropropagated plantlets and production of microtubers of Diacol Capiro and Parda Pastusa; the plantlets and microtubers developed can be cultured under controlled conditions for the production of pre-basic seeds.Bibliografía: páginas 29-31