Crowning is one of the oldest dental techniques, but it’s changed a lot since gold caps!
Crowning is an excellent option for teeth that have gone beyond the point where filling would be effective. They are suitable if decay has structurally compromised the tooth, but its underlying root is still strong and healthy and has not been infected. The health of the patient’s root is usually ascertained with an X-ray before continuing with the procedure.
Preparing the tooth
To instal a crown the original tooth requires extensive preparation. This used to involve cutting down the tooth to a suitable peg and being fitted to the bottom by a standardised interface with a crown, but this is no longer practised at a dentist in Tunbridge Wells. Instead, the minimum quantity of natural tooth is removed and once the tooth is free from decay, the remaining surface is then scanned or moulded in order to give the precise dimensions. This is sent on to a partner dental laboratory who fabricates a crown that matches the patient’s tooth specifications, saving as much of the natural tooth as possible and providing a strong, well-meeting surface without gaps of vulnerability for further future cavities.
Fitting and maintenance
Once a crown is fabricated, fitted and held in place using dental cement, this provides a strong bond against the daily wear and tear that teeth have to go through. Its maintenance requirements are much like any other tooth in terms of daily brushing and flossing, as well as 6 monthly check-ups to catch possible issues early. Unlike bridges, there is no particular special maintenance or change in daily hygiene, making them easier for many people to use.
What about in-situ crowning?
In-situ crowning is a relatively modern technique that involves the application of multiple layers of UV cured resins; the crown is built directly in the patient’s mouth and it has some advantages. The procedure takes place in a single session rather than having to use a temporary crown between the preparation and the fitting stage as with traditional crowning. It is not offered in all dental clinics as it requires significantly more skill on behalf of the dental staff, in not only applying the resin correctly, but also in matching colour, tone and translucency of the resin to the rest of the enamel, as well as the final sculpting. This is important in giving a seamless natural-looking finish to this treatment.
What about metal crowns?
Metal crowns are still available, but apart from niche cosmetic purposes, gold crowning has largely been considered obsolete in favour of porcelain composites or in-situ, resin-based techniques. The lifespan of gold crowns is significantly shorter, due to the softness of the metal and silver or metal amalgam crowns, many of which have thermal expansion issues, result in debonding of the crown more often than porcelain composites.
A porcelain-polymer jacketed crown with metal core is still the preferred treatment according to NHS guidelines and the only ones that they will financially contribute to, but the guidelines may change in the coming years.