Bone grafting and its effect on stablilty of the jaw on extraction patients: a systematic review

Tooth extraction is necessary when there is advanced decay, significance trauma or injury to the oral cavity, misalignment associated with crowded teeth or even, poor eruption of third molars. Typically, during extraction procedures, bone grafting material is inserted to minimize bone loss. Bone grafting has become a standard procedure in dentistry and an essential component in modern medicine. The practice started nearly 350 years ago when a Dutch doctor in 1668 performed the first and successful bone grafting operation. Currently, research studies are ongoing to enhance the success and viability of dental reconstruction. This thesis examines the effect of varying dental graft techniques and methodology on the stability and long-term effect on the jawbone. These techniques include five primary bone grafting methods, onlay, inlay, ridge expansion, distracted osteogenesis and guided bone regeneration (GBR) have been approved to enhance the outcome of dental implants. The review has presented the documented limitations and viability of each method. In this paper, the alternatives to bone grafting have also been elaborated. Based on the findings depicted in this research, the following recommendations will assist in achieving the best jawbone outcomes in long-term and short-term assessments. These recommendations are as follows, a proper evaluation of each patient to determine their health condition. The nature of the infection, injury, and trauma that led to the extraction of the tooth should be well documented. The selection of technique pertaining to dental restoration, functionality, and aesthetic needs are of primary factors considered. A proper clinical follow-up and monitoring of recovery process is an essential part that contributes to valid results. Finally, patient awareness is essential as well. The study found out that although some of the bone grafting techniques have shown a high survival rate, significant alveolar bone quality and quantity, and success of the implants, several reports that the use of bone grafts and implants is a practice that will still dominate dental surgery and attract more clinical assessments

Numerical and experimental study of steady and unsteady mixed convection flow in a cubical open cavity with the bottom wall heated

En aquest estudi s'analitzen els experiments i simulacions numèriques del flux de convecció mixta en una cavitat cúbica situada a la part inferior d'un canal quadrat. Els nombres de Reynolds en funció de la velocitat mitjana del flux i l'amplada del canal estan en el rang 100≤Re≤1500 i el nombre de Richardson varia entre 0.1≤Ri≤10. La tècnica PIV s'ha utilitzat per a les mesures en un canal d'aigua. Simulacions numèriques Tridimensionals s’han dut a terme amb un codi de volums finits de segon ordre considerant l'aproximació de Boussinesq ja que, per les condicions experimentals utilitzades, la variació de les propietats físiques amb la temperatura no té influència significativa en la topologia general de flux. Per 100≤Re≤1500 i Ri≤0.1 el flux és estacionari i consisteix en un remolí situat a l’interior de la cavitat cúbica que mostra velocitats majors a mesura que augmenta el nombre de Richardson. El flux és no estacionari a Re = 100 i Ri = 10. Prop de les parets laterals es produeixen, de forma alternada, ejeccions de flux, des de l’interior de la cavitat cap al canal, mentre que el flux entra a la cavitat des del canal a través de la part central de la cavitat. S'ha utilitzat una tècnica de mostreig condicional per elucidar l’estructura mitjana de l'evolució del flux turbulent a Ri = 10. S'ha trobat que les ejeccions de flux persisteixen durant tot el rang de Reynolds analitzat. Els números de Nusselt calculats estan d'acord amb els de les correlacions reportades a la literatura, vàlides per cavitats bidimensionalsEn este estudio se analizan los experimentos y simulaciones numéricas del flujo de convección mixta en una cavidad cúbica situada en la parte inferior de un canal de sección cuadrada cuadrado. Los números de Reynolds en función de la velocidad media del flujo y la anchura del canal están en el rango 100≤Re≤1500 y el número de Richardson varía entre 0.1≤Ri≤10. La técnica PIV se ha utilizado para las medidas en un canal de agua. Se han llevado a cabo simulaciones numéricas tridimensionales con un código de volúmenes finitos de segundo orden, considerando la aproximación de Boussinesq ya que, en las condiciones experimentales utilizadas, la variación de las propiedades físicas con la temperatura no tiene influencia significativa en la topología general de flujo. En los rangos 100≤Re≤1500 y Ri≤0.1 el flujo es estacionario y consiste en un remolino situado en el interior de la cavidad cúbica que muestra velocidades mayores a medida que aumenta el número de Richardson. El flujo es no estacionario a Re = 100 y Ri = 10. Cerca de las paredes laterales se producen de forma alternada eyecciones de flujo, desde el interior de la cavidad hacia el canal, mientras que el flujo entra en la cavidad desde el canal a través de la parte central de la cavidad. Se ha utilizado una técnica de muestreo condicional para elucidar la estructura media de la evolución del flujo turbulento a Ri = 10. Se ha encontrado que las eyecciones de flujo persisten durante todo el rango de Reynolds analizado. Los números de Nusselt calculados están de acuerdo con los de las correlaciones reportadas en la literatura, válidas para cavidades bidimensionales.In this study we analyze experiments and numerical simulations of steady and unsteady mixed convection flow in a cubical cavity located at the bottom of a square channel. The Reynolds numbers based on the mean flow velocity and the channel width are in the range 100≤Re≤1500 and the Richardson numbers vary within 0≤Ri≤10. Particle Image Velocimetry has been used for the measurements in a water channel. Three-dimensional direct numerical simulations have been carried out with a second order finite volume code considering the Boussinesq approximation since, for the experimental conditions considered, the variation of the physical properties with temperature has no significant influence on the overall flow topology. For 100≤Re≤1500 and Ri≤0.1 the flow is steady and it consists in a single roll that exhibits larger velocities as the Richardson number is increased. An unsteady periodic flow is found at Re=100 and Ri=10. Alternate flow ejections from the cavity to the channel occur near the lateral walls while the flow enters the cavity from the channel through the central part of the cavity. A conditional sampling technique has been used to elucidate the evolution of the mean unsteady turbulent flow at Ri=10. It has been found that the alternate flow ejections persist for all the Reynolds analyzed. The computed Nusselt numbers are in general agreement with a previously reported correlation, valid for two dimensional cavities of different aspects ratios

External ankle supports and ankle sprains: A current perspective

External ankle supports (taping and bracing) are used to aid in the treatment and prevention of lateral ankle sprains. This thesis critically reviews the current evidence and presents original research surrounding the effectiveness of ankle taping and bracing on biomechanical and functional performance outcomes. Chapter 2 highlights the effects of ankle supports on lower limb biomechanical outcomes during functional tasks (jumping/landing, running, walking, side cut) in people with and without a history of lateral ankle sprains, by presenting the results of a systematic review with meta-analysis that used a within-participant (repeated measures) design and compared outcomes with and without ankle supports. The scoping review in Chapter 3 explored the current recommendations and indications for ankle brace use. Based on clinical guideline recommendations (Chapter 3) and the results of the systematic review (Chapter 2) showing that ankle braces did not have an effect on biomechanical outcomes, this thesis set out to explore if ankle bracing had any effect on functional performance (Chapter 4) through a randomized double-blinded cross-over trial. This thesis set out to explore also if ankle taping had any effect on functional performance (Chapter 5) through a retrospective cross-sectional analysis. Drawing on the conclusions from previous chapters, an Australian national survey was developed (Chapter 6) in order to understand the current attitudes and practices of health care and sports workers using ankle supports to manage and prevent lateral ankle sprains. In summary, ankle supports are effective and their use has been recommended for management and prevention of lateral ankle sprains by both practitioners and guidelines

Phenotypical Characterization of Human Rhinovirus Infections in Severely Premature Children

Background: Human Rhinovirus (HRV) has been identified as the most common cause of acute respiratory infections and hospitalizations in premature children. It is unclear if premature children are more susceptible to HRV due to their decreased pulmonary reserve or because they have enhanced lower airway reactivity to HRV. Methods: We conducted a retrospective analysis of the clinical respiratory presentation of all PCR-confirmed HRV infections in full-term and premature children aged ≤ 3 years in our institution. Standardized respiratory distress scores were developed to examine lower airway obstruction (i.e., wheezing, hyperinflation, and sub-costal retractions) along with markers of decreased pulmonary reserve (hypoxemia and tachypnea) in young children with HRV infections. Demographic and clinical variables were obtained from reviewing electronic medical records (EMR). Results: This study included a total of 205 children; 71% of these children were born full-term (\u3e 37 weeks gestation), 10% preterm (32–37 weeks) and 19% severely premature (\u3c 32 weeks). Our results demonstrated that: 1) HRV infections in the first 3 years of life were associated with higher overall respiratory distress scores in severely premature children relative to children born preterm or full-term; 2) HRV-infected severely premature children ≤ 3 years old were more likely to have lower airway obstruction than HRV-infected children born preterm or full-term; and 3) other clinical signs of respiratory distress such as tachypnea and hypoxemia were not more common in severely premature than in preterm and full-term children during an HRV infection Conclusions: Our results indicate that HRV infections in severely premature children are associated with lower airway obstruction rather than hypoxemia or tachypnea. The latter suggests that enhanced airway reactivity is the underlying mechanism for the increased susceptibility to HRV in severely premature children. Longitudinal studies are needed to understand why premature babies develop airway hyper-reactivity to HRV and the long-term effects of early HRV infection in this population

Age-Related Effect of Viral-Induced Wheezing in Severe Prematurity

Abstract: Premature children are prone to severe viral respiratory infections in early life, but the age at which susceptibility peaks and disappears for each pathogen is unclear. Methods: A retrospective analysis was performed of the age distribution and clinical features of acute viral respiratory infections in full-term and premature children, aged zero to seven years. Results: The study comprised of a total of 630 hospitalizations (n = 580 children). Sixty-seven percent of these hospitalizations occurred in children born full-term (\u3e 37 weeks), 12% in preterm (32–37 weeks) and 21% in severely premature children (\u3c 32 weeks). The most common viruses identified were rhinovirus (RV; 60%) and respiratory syncytial virus (RSV; 17%). Age-distribution analysis of each virus identified that severely premature children had a higher relative frequency of RV and RSV in their first three years, relative to preterm or full-term children. Additionally, the probability of RV- or RSV-induced wheezing was higher overall in severely premature children less than three years old. Conclusions: Our results indicate that the vulnerability to viral infections in children born severely premature is more specific for RV and RSV and persists during the first three years of age. Further studies are needed to elucidate the age-dependent molecular mechanisms that underlie why premature infants develop RV- and RSV-induced wheezing in early life