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Aim of study: No evidence is found in literature to assess that malocclusion can lead to postural or craniocervical–mandibular disorders. The aim of this study is to investigate with surface electromyography (EMG) of masticatory muscles and stabilometric analysis the relationship between malocclusion and presence of temporomandibular disorders (TMDs) or postural variations in a group of athletes of different sports. Materials and methods: Seventy-four athletes belonging to different sport societies were included in this study. Chi-square test, taking as significance index χ​2 > 0.05, was used to compare in pairs the postural interference, muscle disharmony, malocclusion, and TMDs. Results: No statistical significance emerged, correlating postural interference and muscle disharmony (χ​2 = 0.15), muscular imbalance, and anatomical findings of malocclusion (χ​2 = 0.62), muscular imbalance and TMDs (χ​2 = 0.15), and TMDs and malocclusion (χ​2 = 0.09). Statistically significant association [χ​2 = 0.019, odds ratio (OR) = 3.10] emerged from the correlation between TMDs and postural interference. Conclusion: A correlation between posture and occlusion is very difficult to be demonstrated. A multidisciplinary approach is required for TMDs: therapy with oral splints allows to give greater compliance to the system by allowing muscles to guide the jaw in a position of functional equilibrium. Clinical significance: Gnathological treatment evaluated through EMG and stabilometric platform allows to obtain improvements in the occlusal balance.

Old precast buildings are often characterized by poor detailing that may hamper the structural performance, particularly in the case of earthquakes. This is essentially related to: (i) a limited past knowledge of seismic design and behaviour, also reflected in past building codes; (ii) the evolution of seismic zonation of the Italian territory. The aim of this work is to assess the probabilistic seismic vulnerability with respect to the usability preventing damage and global collapse performance levels of four existing single-story precast buildings designed in accordance with past Italian building codes from 1960s to 1990s in three sites with increasing seismic hazard.

Seismic performance-based design approach is currently implemented in modern building codes. Design requirements and provisions ensure an adequate structural performance under different intensity levels of seismic action. However, the probability of attainment of a performance level is implicitly considered in the code design approach (provisions and requirements); for instance, the minimum requirements in concrete structures cannot be simply correlated to the probability of collapse of the building as well as to its overall structural response. The aim of this work is to assess the vulnerability with respect to the collapse limit state of industrial single-story RC precast buildings designed according to the current Italian seismic code. The comparison between the Italian code and the Eurocodes is provided throughout the paper. A parametric study is performed by investigating the safety against the collapse of 40 RC single-story precast structures. Multi-stripe analyses are performed by non-linear dynamic analyses at 10 intensity levels. The fragility of the structures is defined by means of the incremental N2 method, which has been demonstrated to be a suitable method for evaluating the collapse capacity of single-story precast buildings. The results demonstrate that the buildings are safe against the collapse mainly because of the structural overstrength with respect to seismic actions. The modelling assumptions are also validated in order to demonstrate the negligible influence of the cracking on the collapse as well as the importance of the geometrical nonlinearities for precast buildings.