A custom-made device (CMD) is a medical device intended for the sole use of a particular patient. In a dental setting, CMDs include prosthodontic devices, orthodontic appliances, bruxism splints, speech prostheses and devices for the treatment of obstructive sleep apnoea, trauma prevention and orthognathic surgery facilitation (arch bars and interocclusal wafers). Since 1993, the production and provision of CMDs have been subject to European Union (EU) Directive 93/42/EEC (Medical Device Directive, MDD) given effect in the UK by The Medical Devices Regulations 2002 (Statutory Instrument 2002/618), and its subsequent amendments. Regulation (EU) 2017/745 (Medical Device Regulation, EU MDR) replaces the MDD and the other EU Directive pertaining to Medical Devices, Council Directive 90/385/EEC (Active Implantable Medical Device Directive, AIMDD). The EU MDR was published on 5 April 2017, came into force on 25 May 2017 and, following a three-year transition period was due to be fully implemented and repeal the MDD on 26 May 2020, but was deferred until 26 May 2021 due to the coronavirus disease 2019 (COVID-19) pandemic. In the UK, in preparation for the country’s planned departure from the EU, the EU MDR, with necessary amendments, was transposed into UK law (Medical Devices (Amendment etc.) (EU Exit) Regulations 2019, UK MDR). The UK left the Union on 31 January 2020 and entered a transition period that ended on 31 December 2020, meaning that, from 1 January 2021, dental professionals in Great Britain who prescribe and manufacture CMDs are mandated to do so in accordance with the new legislation while Northern Ireland remains in line with the EU legislation and implementation date. This paper sets out the requirements that relate to the production and provision of CMDs in a UK dental setting.