Dr Michael B Lewis

A dental bridge can replace one or more teeth by joining a false tooth permanently to crowns on either side of a missing tooth. Bridges have been used to replace missing teeth for over a century and are an alternative fixed treatment option to dental implants. Unlike dentures, bridges are not removable, and stay fixed in your mouth all the time.

Dental implants are often advertised as “the panacea for missing teeth”. Not every patient or site will yield a good outcome with dental implants. The cost, appearance, function and longevity of bridges and implants is fairly similar and although the trend in our practice is to replace teeth with dental implants, there are times when we will recommend a bridge over implant therapy. Unlike implants, bridges do not require a surgical procedure. They are also completed in a fraction of the time when compared to implant surgery as there are no waiting times for extraction sockets to heal or implants to fuse with the bone. Furthermore the longevity of implants and bridges is roughly comparable and if anything they look better as their appearance is not based on the remaining bone and gum. That being said, a bridge requires the teeth on either side of a missing tooth to be prepared for crowns. This may be a good thing if the adjacent teeth need crowns anyway as you are effectively “killing two birds with one stone”. The biological invasiveness of preparing a tooth for a crown must be carefully weighed-up against other variables such as patient age, surgical fitness and any additional procedures that may be required to build-up a site for implant placement. In general, the need for bone grafting generally will both increase the cost and decrease the expected lifespan of an implant crown. At Queensland Prosthodontics, you will be informed of all the treatment choices and we will guide you as to which approach is in your best interests.

A Prosthodontist is a board-registered specialist in crown and bridge. Any other stated qualification (i.e. cosmetic dentist, neuromuscular dentist, etc) is a self-dubbed title and just means the dentist has an interest in that procedure. It would be reasonable to expect that a Prosthodontist would be more skilled in both the diagnostic and procedural aspects of crown and bridge. They are also highly aware of the biological costs of such procedures and should be more discerning when prescribing crowns.

Replacement of a tooth with a bridge generally takes two visits that are three weeks apart: 1. At the first appointment, the adjacent teeth are prepared for crowns - any old filling material is removed and the remaining tooth structure is bonded together. Then the teeth are shaped at a specific taper in order to create space for the future bridge. At the conclusion of this appointment we make you a temporary bridge so that you can smile, talk and eat as well if not better than you did before while the final bridge is made. 2. At the second appointment the bridge is tried-in, adjusted and cemented. There is generally a three-week space between the preparation and cementation appointment - this is the time it takes to get a premium lab to make bridges that we would be comfortable to put our name to.

At Queensland Prosthodontics our focus is to produce the best crowns and bridges possible for our patients - that is use the best materials, techniques and dental technicians we can source. If sending Dental work overseas or using chair-side milling machines improved our quality we would do it! Unfortunately this is not the case and all these approaches do is increase the profit-margin for the treating clinician - not the quality for the patient! Dental Laboratories that make “cheap crowns and bridges” often send their work to China (such as Southern Cross Dental Laboratory), use non-gold containing metal alloys or mill the bridges in the dental office using a CNC machine. Each of these cost-cutting measures compromises the longevity, biocompatibility and aesthetics of crowns and bridges. “Same-day crowns and bridges” are made in the dental surgery by a milling machine (i.e. Cerec, E4D). These prostheses are literally carved out of a solid block of ceramic that is one flat colour. These types of restorations only take one appointment and are cheaper as they eliminate the expense of sending work to a dental laboratory. There are a number of drawbacks to this treatment approach: • Same-day crowns and bridges tend not to fit as well which is a problem for gum inflammation, dental decay and tooth-sensitivity. • They don’t look like natural teeth - they are milled out of a solid block of ceramic, hence they are one solid colour and tend to be quite opaque. • The milling machine cannot mill intricate internal line angles, hence tooth-reduction has to be more aggressive. • Same-day bridges are weaker when compared to lab-made crowns - The only ceramic material that a chair-side milling machine is capable of milling a 3-unit bridge out of is lithium- (Emax). The literature indicates this material has a poor survival as a bridge when compared to metal ceramic or zirconia. Both the later materials cannot be done in a same-day approach. All our crowns and bridges are hand-made by premium dental laboratories and there is a fair bit of skill that goes into each and every tooth. We also only use the best dental ceramics and high gold-content to make our crowns and bridges. As such our dental technicians charge a premium for their time, skill and use of the best materials and this cost is reflected in our fees.

Apart from the appearance of a bridge, a patient is not the best person to assess the quality of their dental work. A patient is able to judge the quality of an experience - that is how compassionate the dentist was, how nice the waiting room may be and whether the dentist was confident executing the treatment. It often comes as a surprise to a patient if their bridge is failing or of poor technical quality. While the experience is important, the look, fit, contour and bite on a crown is what ultimately will affect how happy a patient is with their dental restorations. What we look for when we assess the quality of crown and bridge are: • The fit is one of if not the most important factors when assessing the quality of a bridge. If we consider the size of an individual bacterium that cause gum disease and decay (5 millionths of a metre) then it is clear why the fit is so critical. There are two important ways to assess if a crown fits well: • Clinically - When we run a probe along the join where a bridge margin meets natural tooth we want this junction to be minimally if at all perceivable. If there is a gap between the two interfaces then it is likely to be filled with millions of bacteria which cause decay and gum disease. • Radiographs - It is extremely difficult to clinically examine the fit of bridges between teeth as access is obscured by the neighbouring tooth. The area between teeth is the area most prone to dental decay hence radiographs are an essential tool to check for decay under crowns. An X-ray of a well fitting crown should show a confluent junction between the crown and tooth without a void, step or abrupt change in contour between a crown and tooth. • Well made bridges should camouflage in with the other natural teeth - here we are looking for natural shapes and shades that blend in with the other neighbouring teeth. Teeth are not one solid colour - the shade develops between the different regions of the tooth and they are translucent, multidimensional structures. This is why chair-side milled crowns (i.e. Cerec, E4D) or monolithic ceramics (i.e. monolithic zirconia) do not look natural. • A bridge should be in your bite in harmony with the other natural teeth - being “too high” or out of your bite is a bad thing: • If a bridge is shy of your bite then it will cause extra burden on the teeth touching. • If the bridge is too highthis can cause irreversible damage to the crown, the tooth it is biting against or your jaw-joints.

Having dental work done in developing-countries such as Thailand, Bali or India is obviously far less expensive than Australia. Generally it is impossible to talk a patient out of going down this path as they view dental treatment as a “commodity" as opposed to a “skill-based service”. They think they are getting “like-for-like” for a fraction of the cost - but this is far from the truth. Many of these clinics have opulent waiting rooms and operatories which give the impression of quality however if we recall patients can only judge the quality of an experience, not the technical quality of the dental work they are receiving. Firstly it is important to state that the only thing that is cheaper overseas is labour. The cost of high quality materials (i.e. gold, branded ceramics, etc) and main-brand dental components (i.e. Straumann, Nobel, Astra, etc) is standardised across the globe. So there is a baseline cost that cannot be avoided without using dodgy materials or counterfeit implant components. If the price of a procedure seems too good to be true, it probably is! It would be a falsity to say that Australia is the only place where quality dental care exists. However if you have a crown done in the town where you live the clinician is medico-legally accountable for their work. They will continue to see it year after year. If it fails you are likely to go back to them. In the case of travel-dentistry no-one is accountable. International crowns, bridges and implants only have to last the duration of your stay in their country. In the event of a dental emergency it is unlikely you will have the time or finances to drop everything and fly back to the country where you were treated to have the dental work rectified. In the event of negligence it would be a near impractical to take action against an overseas clinic with a foreign legal system. Clinics that hunt for dental tourism know this and exploit these loopholes. As I said before - it is a near impossibility to talk a patient out of going down the path of overseas dentistry if this is what they have set their mind to. And whilst there may be success stories I am unaware of them. In a nutshell it is all about risk - crowns, bridges and implants are irreversible, invasive procedures that require careful monitoring and maintenance for the duration of their lifespan. In the case of overseas dental work no-one is accountable and in the event of failure you will wind up in a worse situation than when you started. Any initial savings would pale in comparison to what it may cost to fix up such work.