Aim: To determine if digital study models are a satisfactory alternative to plaster study models. Method: 1. Pilot study to compare linear measurements from plaster models with two types of digital model. 2. Study to compare PAR scores from plaster models with digital models created from scans of dental impressions. 3. Pilot study to compare PAR scores of plaster models with 30 printed models created from scans of dental impressions. Results: A mean difference of <O.5mm (range 0.02-0.51 mm) for single linear measurements and <3.0mm (0.47-3.03mm) for multiple linear measurements was indicated. A mean difference of 0.03 PAR points (SD=3) was demonstrated between PAR scores for plaster models and digital models. A mean difference of 1 PAR point (SD=3) was demonstrated between PAR scores for plaster models and 30 printed models. Conclusions: Both types of digital study model may be comparable with plaster models when used for linear measurements. Digital models created from scans of dental impressions are indicated to be comparable with plaster models for PAR scoring. 30 printed models may be comparable to plaster models for PAR scoring. Further research using a larger sample size is required to confirm above conclusions with regard to validity and reliability
