There is a paucity of research concerning paediatric dental consultations in primary care. This is potentially due to the difficulty of measuring the communication behaviours in the complex triadic consultations. The present study aims to describe the development and refinement of a coding scheme to record the triadic communication between dental professionals, child patients and parents.The PaeD-TrICS was developed from video observation of triadic communications and refined through an iterative process. Its practical applicability was assessed via implementation of the scheme on specialised behavioural coding software. Reliability was calculated using Cohen's Kappa.The PaeD-TrICS contains 45 codes. Forty-four dental professional-child-parent communications were successfully coded through administering the scheme on The Observer XT 10.5 system. Cohen's Kappa was 0.83 (inter-coder) and 0.90 (intra-coder). "Parental verbal facilitation" (mean = 1.68/min) was the most frequent behaviour. Dental professionals' "dentally engaging talk" (mean = 1.24/min), "praise" (mean = 1.10/min) and "instruction" (mean = 0.62/min) were frequently seen. Children's common behaviours included "speech other" (mean = 0.66/min) and non-verbal behaviour i.e. "non-verbal agreement" and verbal behaviour "speech yes" (mean = 0.26/min).The PaeD-TrICS is developed to capture the communication behaviour of the triadic consultations in a preventive dental setting. It demonstrates satisfactory intra- and inter-coder reliability and has been successfully used in paediatric dental consultations.