A case of mental nerve paresthesia due to dynamic compression of alveolar inferior nerve along an elongated styloid process

Spontaneous paresthesia of the mental nerve is considered an ominous clinical sign. Mental nerve paresthesia has also been referred to as numb chin syndrome. Several potentially different factors have been investigated for their role in interfering with the inferior alveolar nerve (IAN) and causing mental nerve neuropathy. In the present case, the patient had an elongated calcified styloid process that we hypothesized had caused IAN irritation during mandibular movement. This eventually resulted in progressive loss of sensation in the mental nerve region. To our knowledge, this dynamic irritation, with complete recovery after resection of the styloid process, has not been previously reported

Influence of BSSO surgical technique on postoperative inferior alveolar nerve hypoesthesia: a systematic review of the literature

Objective The aim of this study was to evaluate the influence of different splitting techniques, namely, "mallet and chisel" versus "spreading and prying", used during bilateral sagittal split osteotomy (BSSO) on postoperative hypoesthesia outcomes. Study design We systematically searched the PubMed and Cochrane databases (from January 1957 to November 2012) for studies that examined postoperative neurosensory disturbance (NSD) of the inferior alveolar nerve (IAN) after BSSO. Results Our initial PubMed search identified 673 studies, of which, 14 met our inclusion criteria. From these 14 studies, 3 groups were defined: (1) no chisel use (4.1% NSD/site), (2) undefined chisel use (18.4% NSD/site), and (3) explicit chisel use along the buccal cortex (37.3% NSD/site). Conclusion Study heterogeneity and a frequent lack of surgical detail impeded our ability to make precise comparisons between studies. However, the group of studies explicitly describing chisel use along the buccal cortex showed the highest incidence of NSD. Moreover, comparison of the study that did not use chisels with the 2 studies that explicitly described chisel use revealed a possible disadvantage of the "mallet and chisel" group (4.1% versus 37.3% NSD/site). These results suggest that chisel use increases NSD risk after BSSO

A 3-D finite element model for thermal analysis of laser assisted fiber placement

Laser assisted automated tape or fiber placement (LATP/LAFP) with in-situ consolidation is a promising technique for manufacturing large structures, eliminating the limitations of autoclave curing. Currently, 2-D models are mostly preferred for the thermal analysis of the process. A 3-D, transient thermal finite element model is developed to analyze the effect of the alignment of the heat source with the tape laying direction and is compared with a model imitating a 2-D analysis space. This aspect of the process has not been considered in the literature so far. Effects of this aspect on temperature history and intimate contact evolution are presented.Structural Integrity & CompositesAerospace Structures & Computational Mechanic

Breeding amiable animals? Improving farm animal welfare by including social effects in breeding programmes

Social interactions between individuals, such as co-operation and competition, are key factors in evolution by natural selection. As a consequence, evolutionary biologists have developed extensive theories to understand the consequences of social interactions for response to natural selection. Current genetic improvement programmes in animal husbandry, in contrast, largely ignore the implications of social interactions for the design of breeding programmes. Recently, we have developed theoretical and empirical tools to quantify the magnitude of heritable social effects, ie the heritable effects that animals have on their group mates' traits, in livestock populations, and to utilise those effects in genetic improvement programmes. Results in commercial populations of pigs and laying hens indicate large heritable social effects, and the potential to substantially increase responses to selection in traits affected by social interactions. In pigs, including social effects into the breeding programme affected aggressive behaviour, both at mixing and in stable groups, indicating changes in the way dominance relationships are established and in aggressiveness. In laying hens, we applied selection between kin-groups to reduce mortality due to cannibalistic pecking. This resulted in a considerable difference in mortality between the low mortality line and the unselected control line in the first generation (20 vs 30%). Furthermore, changes in behavioural and neurobiological responses to stress were detected in the low mortality line, pointing to reduced fearfulness and stress sensitivity. These first results indicate that including social effects into breeding programmes is a promising way to reduce negative social interactions in farm animals, and possibly to also increase positive social interactions, by breeding animals with better social skill

Breeding amiable animals? Improving farm animal welfare by including social effects in breeding programmes

Social interactions between individuals, such as co-operation and competition, are key factors in evolution by natural selection. As a consequence, evolutionary biologists have developed extensive theories to understand the consequences of social interactions for response to natural selection. Current genetic improvement programmes in animal husbandry, in contrast, largely ignore the implications of social interactions for the design of breeding programmes. Recently, we have developed theoretical and empirical tools to quantify the magnitude of heritable social effects, ie the heritable effects that animals have on their group mates' traits, in livestock populations, and to utilise those effects in genetic improvement programmes. Results in commercial populations of pigs and laying hens indicate large heritable social effects, and the potential to substantially increase responses to selection in traits affected by social interactions. In pigs, including social effects into the breeding programme affected aggressive behaviour, both at mixing and in stable groups, indicating changes in the way dominance relationships are established and in aggressiveness. In laying hens, we applied selection between kin-groups to reduce mortality due to cannibalistic pecking. This resulted in a considerable difference in mortality between the low mortality line and the unselected control line in the first generation (20 vs 30%). Furthermore, changes in behavioural and neurobiological responses to stress were detected in the low mortality line, pointing to reduced fearfulness and stress sensitivity. These first results indicate that including social effects into breeding programmes is a promising way to reduce negative social interactions in farm animals, and possibly to also increase positive social interactions, by breeding animals with better social skill

Estudo da interação polímero/cartilagem/osso utilizando poli (ácido lático-co-ácido glicólico) e poli (p-dioxanona) em condilo femural de coelhos Study of polymer/cartilage/bone interaction using poly(lactic acid-co-glycolic acid) and poly (p-dioxanona) in femoral condyle of rabbits

Os dispositivos biorreabsorvíveis são alternativas para fixação interna das fraturas. Durante o tratamento estes dispositivos mantêm a fixação e degradam-se gradualmente não necessitando de uma cirurgia de remoção, reduzindo o custo de tratamento quando comparadas aos dispositivos metálicos. O objetivo desse trabalho foi estudar a interação polímero/tecido utilizando pinos de PLGA e PDS após implantes em coelhos Nova Zelândia. Separou-se os animais em 3 grupos os quais foram sacrificados após 3, 6 e 12 semanas de implantação e o material obtido foi submetido à análise histológica. As análises histológicas com implantes de PLGA mostraram após 3 semanas a formação de um tecido com características mesenquimatosas e com 12 semanas a formação de uma estrutura óssea madura. Já nos implantes de PDS de 3 semanas houve uma maior invasão de tecido mesenquimal comparado ao PLGA e após 12 semanas, ocorreu uma degradação avançada, com tecido proliferativo mesenquimal e ósseo. Assim, concluiu-se que ocorreram resultados positivos à resposta tecidual/implante e foi relevante a observação da ausência de células responsáveis pela resposta inflamatória. As análises demonstraram que o copolímero de PLGA apresentou propriedades osteoindutivas mais adequadas que os de PDS, apresentando biocompatibilidade aceitável para aplicação ortopédica.<br>Bioresorbable devices are alternatives for internal fixation. During the treatment, those devices maintain the fixation, degrade gradually and eliminate the need for a remove surgery, decreasing the treatment cost when compared with metallic devices. The aim of this work was to study the interaction polymer/tissue interaction using pins of PLGA and PDS implanted in New Zealand rabbits. The animals were separated in 3 groups which were sacrificed after 3, 6 and 12 weeks after implantation, and the obtained material was submitted to histological analysis. Histological analysis with PLGA implants showed after 3 weeks, the growth of a tissue with mesenchimal characteristics, after 3 weeks, with formation of mature bone aready after 12 weeks. PDS implants after 3 weeks showed a bigger invasion of mesenchimal tissue compared to PLGA and after 12 weeks an advanced degradation occurred, with proliferation of mesenchimal and bone tissue formation. It is concluded that the results are highly positive, with the relevant absence of cells responsible for inflammatory response. Analysis showed that the copolymer PLGA has better ostoinductive properties than PDS, showing biocompatibility acceptable for orthopedics application