Introduction Bruxism is defined as a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible [ 1 ]. Its effects can be deleterious to the oral tissues and restorations, which highlights the importance of insight towards the fundamental aspects of occlusion in each patient. Dentists should therefore study and examine the individual occlusal schemes in order to plan and treat these patients [ 2 ]. Materials and methods Patient, male, 22 years old, with tooth wear compatible with bruxism. The diagnosis was made based on a multiple level of sensibility determined by the 2018 Bruxism Consensus of possible, probable or definitive diagnosis of bruxism. We applied a specific sleep bruxism questionnaire [ 3 ] plus a clinical examination and questionnaire about clinical signs and symptoms based on the Diagnostic Criteria for Temporomandibular Disorders [ 4 ]. After we applied an intra oral red coloured device for evaluation of bruxism during sleep for two, Bruxchecker®, and at the same time the patient slept with an electromyography device in the temporal muscle called Grindcare® with recording of audio and video during sleep. All the assumptions of the Helsinki Declaration have been fulfilled and an informed consent for clinical case of Clinica Dentária Egas Moniz approved by the ethic commission of Instituto Universitário Egas Moniz. Results We have a positive diagnose for definitive bruxism confirmed with 15.6 grindings/clenching bursts per hour on the first night and 4.7 grindings/clenching bursts per hour on the second night, with audio and video we could have the perception of sounds compatible with problems of the respiratory system but absence of sounds and images compatible with tooth grinding. Clinically signs of tooth attrition were observed as well as tongue and cheek indentations, our patient also answered positively to the specific sleep bruxism questionnaire. The Bruxchecker® was helpful to see the dental wear movements. Discussion and conclusions Polysomnography is the gold standard for the diagnosis of sleep bruxism. However, electromyography supplemented with audio and video recordings is increasingly advocated as an equally valid method. The existence of a device like Grindcare ® which measures the number of muscles bursts per hour associated with clinical examination allows to give a definitive bruxism diagnosis if used for a determined number of nights. Bruxchecker ® and Grindcare® results were somewhat confusing on both nights but this is due to extrinsic factors. The result was a definitive sleep bruxism diagnose according to the last bruxism consensus of 2018.

Introduction: The imperfect amelogenesis (IA) is a heterogeneous group of changes that mainly affect the structure of the enamel. It can occur in the deciduous and permanent dentition and presents a variation of phenotype, associated or not to a syndrome [1,2]. The aim of this study is to evaluate the prevalence of IA in patients who were observed for the first time in the Egas Moniz University Clinic and to describe which teeth are most affected. Variables such as sex, age, oral hygiene, diet and DMFT index (decay-missing-filling-teeth) were evaluated. DMFT index was analysed in order to determine if in the presence of enamel changes, correct oral hygiene and low sugar diet, the DMFT index remains high, to determine if the enamel changes have an impact on dental caries in the absence of external factors. Materials and methods: The study was approved by an Ethics Committee of Egas Moniz and a written consent was obtained from all participants.The sample consisted of 100 children who attended Egas Moniz paediatric dentistry, for the first time, over a two-year period (2015)(2016)(2017). Inclusion criteria were: Children without craniofacial changes and that the parents have signed the informed consent. Data were analysed by using descriptive and inferential methodologies. A significance level of 5% was established in the latter case. Results: The mean age was 10.2 years, ranging from 6 to 18 years. The majority (55%) was male and 45% was female. Permanent dentition is the most prevalent (52%), followed by mixed (30%) and deciduous (18%). Of the total sample, it was observed 14% of patients with IA. The permanent dentition presents 50% of IA, followed by 42.9% in the deciduous dentition, reducing in the mixed dentition (7,10%). The most affected teeth were the second upper molars with a S57 ANNALS OF MEDICINE