Title: 3-D Printed Dentures; Development and assessment of cost-effective workflows to enhance clinical delivery
Funder: Dunhill Medical Trust

Abstract: The Adult Dental Health Survey[1] shows 6% of UK adults are completely edentulous. Older adults form the majority of these patients[1]. Existing conventional complete dentures have been shown to be associated with poor diet and lower nutritional intake[2], and ill-fitting dentures are commonplace. The current method of denture production has a known inherent distortion[3,4]. Distortion leads to discomfort and pain. Our new 3-D printed denture fabrication technology can provide more accurately fitting dentures[5]. Other publications reviewing digital denture manufacturing have centered on expensive, clinically inconvenient milling[6,7]; Two recent papers have reported techniques to 3-D print dentures[5,8], but these do not assess outcomes and use expensive scanners. The technology will find particular application among those elderly, sick patients in nursing homes as the fabrication process for new dentures can be done more quickly and avoid anxiety. Furthermore the replacement of any lost 3-D printed denture by a new 3-D printed denture can be simply achieved in a single visit to deliver the new dentures. In these circumstances, copying the familiar, successful old dentures will be of particular benefit to patients with dementia; the new dentures will be a familiar shape enabling easier adaptation. Our 3-D printing technology has been shown to accurately reproduce dentures[5] but needs a clinical pilot study to provide data for a full RCT. The research needs to assess the impact of this technology from the patient’s perspective. Before a full RCT is possible, development work and a pilot study are required. The purpose of the work outlined in this grant application is to enable a full RCT of the new technology. Specifically the grant needs to: 1. Provide an improved optical digital scanner for three centers involved in the study. The scanner needs to be specifically suitable for scanning silicone impressions, the reflective surfaces of dentures, and wax 'trial dentures'. The scanner needs to be inexpensive and easy to use. The grant needs to refine the software for the scanners to produce 3-D printable files automatically, and provide a 3-D printer with printable materials. 2. Use the recognized clinical expertise within the 3 Dental Schools to optimize the clinical workflow to produce high quality dentures efficiently. 3. Assess the accuracy of the denture production in the clinical cases. 4. Run a pilot RCT of 6 clinical cases in each center to test the RCT protocol and enable an accurate sample size calculation for the planned future RCT.

Lay abstract: When a person loses all their natural teeth they are often left with significant deterioration in their chewing ability and appearance, and this impacts negatively on their quality of life. This is especially true for the elderly population who have more severely shrunken gums and a reduced capacity to adapt to new conventional dentures. Well-fitting dentures improve people’s quality of life. We wish to improve the fit and comfort of dentures by fundamentally changing the way dentures are manufactured. For 80 years dentures have been produced by pressing material into a mould and hardening that material with heat and pressure. The hardening process has been shown to cause a small but significant distortion of the denture. We want to develop a better way to process dentures. 3-D printing (also known as 'rapid additive manufacture') is a new way to produce solid objects. It works by 'printing' very thin layers of a material one after another, one on top of another, until a three dimensional shape is built up. This method of producing a solid object can be very accurate and can be applied to dentures. We have previously shown that 3-D printing dentures are more accurate than traditional processing. This can result in a better fit, which can lead to greater comfort. This funding application aims to develop innovative and affordable technology for 3-D scanning to complement existing affordable 3-D printing technologies. The project aims to produce clinical protocols on how to use the new technologies, and run a pilot study which will inform more detailed future research.

Research activity codes: 6.3 MEDICAL DEVICES
Health categories: ORAL AND GASTROINTESTINAL