Patient safety and quality of healthcare delivery systems are an objective of WHO. This study aims to present and analyse Portuguese clinical data on risk and malpractice in dental practice. Data from the Forensic Dentistry Laboratory (Faculty of Medicine, University of Coimbra) was analysed, between the years of 2013 to 2018. One hundred and seven technical reports were selected, and seventy nine files were included in the iatrogenic sequelae group. Data included the analysis of the performance of dental professionals. Sequelae were divided in descending order of occurrence:1) mandibular dysfunction (53,2%)[(42)79]; 2) neurological deficit (39,2%)[(31)79]; 3) tooth loss (6,3%)[(5)79]; and 4) opening deficit (1,3%)[(1)79].Three major areas with significant expression in the field of expert evaluations were analysed: 1) orthodontic treatment (51,9%), implant rehabilitation (29,1%), and oral surgery. Given the prevalence of malpractice, the need to assess its causes and recognise standards for its prevention is necessary.