Objective: To develop a needs-based workforce planning model to explore specialist workforce capacity and capability for the effective, efficient, and safe provision of services in the United Kingdom (UK); and test the model using Dental Public Health (DPH). Basic Research Design: Data from a national workforce survey, national audit, and specialty workshops in 2020 and 2021 set the parameters for a safe effective DPH workforce. A working group drawing on external expertise, developed a conceptual workforce model which informed the mathematical modelling, taking a Markovian approach. The latter enabled the consideration of possible scenarios relating to workforce development. It involved exploration of capacity within each career stage in DPH across a time horizon of 15 years. Workforce capacity requirements were calculated, informed by past principles. Results: Currently an estimated 100 whole time equivalent (WTE) specialists are required to provide a realistic basic capacity nationally for DPH across the UK given the range of organisations, population growth, complexity and diversity of specialty roles. In February 2022 the specialty had 53.55 WTE academic/service consultants, thus a significant gap. The modelling evidence suggests a reduction in DPH specialist capacity towards a steady state in line with the current rate of training, recruitment and retention. The scenario involving increasing training numbers and drawing on other sources of public health trained dentists whilst retaining expertise within DPH has the potential to build workforce capacity. Conclusions: Current capacity is below basic requirements and approaching ‘steady state’. Retention and innovative capacity building are required to secure and safeguard the provision of specialist DPH services to meet the needs of the UK health and care systems. Keywords: Health Services Needs and Demand, Planning, Health Workforce, Public Health Dentistry, Markov Chains, Operational Research