Plain English Summary
Background and study aims
The study is about dental occlusion (contact between teeth) and the aim is to investigate the accuracy of a new, non-invasive ‘optical’ technique to measure the horizontal axis of the jaw (the axis the jaw rotates around, when a subject closes their mouth). This axis needs to be recorded for many dental procedures. Current (mechanical) methods are invasive, time consuming and inaccurate. A simple, accurate method would raise the standard of care through improved diagnosis, treatment planning and better fitting dental prostheses.
Who can participate?
Adult health professionals recruited via posters, group emails and announcements at the end of relevant lectures. This research is part of a PhD.
What does the study involve?
Participants undergo a dental examination to exclude disease. Traditional impressions are then taken of the upper and lower teeth. These are cast in dental stone then digitised, to create ‘virtual’ dental models. Two cameras photograph the subjects’ front teeth. The teeth are illuminated with a pattern projected from a digital projector (rather than a camera flash). This combination enables accurate 3D photographs to be calculated. 3D photographs are taken at two differing degrees of jaw opening (one with the teeth almost touching, and one with a 10mm gape). The axis of jaw rotation can be calculated using these photographs, and the virtual models. The accuracy of this axis is investigated using two methods. Firstly, a 3D photograph is taken at an ‘intermediate’ jaw gape (5mm). The virtual models are rotated around the previously calculated axis, to produce an identical gape (5mm). The position of the virtual models is compared to the measured position. Secondly, the ‘intermediate’ jaw position is physically recorded, using dental bite registration paste (a fast-setting silicone paste, syringed between the teeth). This paste is removed, 3D-scanned and used to align the virtual models. This position is compared to the previously calculated position.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
University of Leeds (UK)
When is the study starting and how long is it expected to run for?
December 2014 to January 2015
Who is funding the study?
Faculty of Medicine and Health, University of Leeds (UK)
Who is the main contact?
Mr Andrew Keeling
Leeds School of Dentistry
6.025 Worsley Building
+44 (0)113 343 1762
Accuracy of optical recordings of the mandibular horizontal axis
With what accuracy can an inexpensive optical method record the mandibular horizontal axis?
University of Leeds Dental Research Ethics Committee, 23/10/2014, ref. 200658679
Single centre - Observing and recording the jaw movements of dentate subjects using a novel optical method, and comparing this to a standard silicone bite registration method
Primary study design
Secondary study design
Cross sectional study
Patient information sheet
Not available in web format, please use the contact details to request a participant information sheet
Subjects will have their jaw relationships measured using standard silicone bite registration material, and using a new optical method.
Primary outcome measure
The distance between reference points on upper and lower digitised teeth will be compared using the standard (silicone) method and the new (optical) method
Secondary outcome measures
Repeatability of these measurements
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Lack of staff/facilities/resources
Participant inclusion criteria
Must have at least 4 upper and 4 lower anterior teeth
Target number of participants
Participant exclusion criteria
No pre-existing disease of the temporo-mandibular joint (jaw joint)
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University of Leeds
Faculty of Medicine and Health, University of Leeds
Funding Body Type
private sector organisation
Funding Body Subtype
Results and Publications
Publication and dissemination plan
This will form the final part of a PhD thesis, and is intended to be published in a high-impact peer reviewed journal.
IPD sharing statement
The datasets generated during and/or analysed during the current study are/will be available upon request from Andrew Keeling (firstname.lastname@example.org)
Intention to publish date
Participant level data
Available on request
Basic results (scientific)