It is important that any dental treatment starts with accurate dental impressions known as dental moulds. This is usually required for many aspects of dental work, however it is essential to plan orthodontic treatment. These dental moulds are used for planning your treatment and also to fabricate the appliances that will be used to obtain the desired tooth movements.
They also ensure that the treatment is done as efficiently as possible. There are many important factors that a dentist that specialises in orthodontics looks at when choosing how to take a dental impression, including:
- Material selection
- Tray design, and
- Oral tissue management.
1.Materials. The most commonly used impression material for orthodontics is an addition-type silicone or polyvinyl siloxane referred to as PVS for short. PVS materials are stable and therefore are ideal for transportation and postage to the place of choice. PVS materials have excellent handling, flow, flexibility, and elastic recovery properties and are very comfortable for the patients. They also have a relatively short setting time, good tear resistance, and have no objectionable tastes and smells.
2. Tray Design. The tray is the plastic vessel which is used to hold the PVS material and allow the clinician to conform it to your teeth and adapt it. This allows a precise copy and the selection of trays is important for accuracy of the impression, and also for your comfort. Trays should be rigid so as to not deform when taking the impression and perforated to retain the PVS in place once it is removed. Sometimes at 128 Harley Street Dental Suite we request custom trays which are needed at times as every individual has different sized-teeth and jaw shapes.
3. Tissue management. Manipulation of the PVS is essential by your treating orthodontist to take an accurate copy of not only your teeth but the surrounding gums. This prevents injury to the tissues of the mouth during preparation and impression-taking. The procedure of taking impressions is done by first preparing the trays, cleaning the site, removing moisture, then syringing the impression material around the tooth, and seating the tray properly. An impression or dental mould with modern materials usually takes around 30 seconds to fully set.
Accurate dental impressions are a fairly common procedure.
Nowadays scanners are also available for a digital copy of your teeth however the gold standard remains dental moulds and more modern scanners are continuously compared to this very well-known and established technique.
Your treatment journey starts here!
Dr. Stefan Abela
BChD, MFDS, RCS Eng, MSc, MORTH RCS Ed, AHEA, FDS Orth RCS Ed
Stefan is a Consultant in Orthodontics at one of the most prestigious London teaching hospitals; Guy’s and St Thomas NHS Foundation Trust.
Stefan is also a specialist in Orthodontics and is registered on the General Dental Council (GDC) specialist list. Stefan qualified as a dental surgeon in 2003 and underwent further training in various specialties including restorative dentistry, paediatric dentistry, oral medicine and complex oral and maxillofacial surgery including the management of facial trauma.