From Volume 39, Issue 6, July 2012 | Pages 422-426
Planning the final aesthetic result of restorative treatment is a key skill needed by the clinician to ensure predictable success. This paper aims to review current techniques that may be used by clinicians for an aesthetic preview, whilst also highlighting a simple technique that may be readily utilized in practice.
The need for an aesthetic preview before commencing definitive treatment is well documented.1,2 In this article we aim to review the several techniques that can be adopted, whilst highlighting an inexpensive, quick and simple method that can easily be used by the general dental practitioner. The development of computer software to aid an aesthetic preview further is a rapidly growing market, however, in this article we aim only to review the 3-dimensional, clinical techniques available.
Managing a patient's expectations is paramount when undertaking all aspects of restorative dentistry.3 In certain areas, such as removable prosthetics, it is commonplace to show and discuss the final result with the patient prior to its construction. However, in fixed prosthodontics in particular, this is not always the case. Patients' demands are ever increasing and it is vital that they can visualize the final result, prior to the start of treatment, whilst also allowing the dentist to highlight any limitations.
The techniques we aim to review are as follows:
A novel technique commonly used in our department will be discussed at the end of the manuscript.
A technique traditionally favoured by many clinicians is the use of articulated study models and the diagnostic wax-up. It involves a lab technician adding wax to an articulated model of the patient's dentition (Figure 1). It allows the clinician to visualize the original dentition, restoration design, occlusal scheme and possible aesthetic outcomes.4
A common error when the technique is used by clinicians is to assume the lab will ‘wax-up’ the teeth in the optimal position required. It is vital for the clinician to prescribe tooth position, size, angulation and design of any prosthesis in detail. Close liaison with the lab is essential during this process.5 It is also important to carry out appropriate reduction of the stone cast before addition of wax to avoid overcontouring and excessive bulk of any future restorations.
The wax-up can also mislead the clinician and patient into believing a result is achievable when, in reality, it is not; an example is not considering pulp anatomy when planning the wax-up.
This diagnostic wax-up can be used to form the cornerstone of discussions with the patient regarding the planned final outcome and is an invaluable tool.6 However, alone it cannot give the patient an idea how the results will look intra-orally and thus has limitations.
The ‘Kesling set-up’,7 more commonly used by orthodontists, is another technique that can show the patient an approximation of the final outcome. It involves a lab technician carefully removing a tooth, or teeth, from a study model and replacing it in a more favourable position. Its use is most valuable when managing tooth movement to create space for restoration using bridges or implants (Figure 2).
This is a simple technique that can be done chairside at the initial appointment. It allows the patient to visualize an approximation of the size, shape, position and, to some degree, the final shade that is achievable. Impressions of the composite ‘mock-up’ can be taken to provide a study model for future reference and to define the treatment goals.
It is obviously not possible to replicate the shape if tooth structure removal is needed. Further disadvantages relate to the use of composite, which can be costly if done regularly, and the difficulty in manipulating the composite quickly.
The application of water soluble ink to teeth was described by Nohl et al in 2002.1 This technique is used where tooth reduction is being considered and involves the painting of the tooth structure that is being considered for removal with water soluble black ink. When viewed in the mouth the results are surprisingly useful.
This technique directly follows on from the wax-up. Once the clinician and patient are happy with the wax-up, the next logical step is to review it intra-orally. There are various different techniques and materials that can be used and have been described in the literature.8,9 The final choice of material generally depends on the length of time the clinician wants the ‘mock-up’ to be in place. The placement of stained, linked acrylic resin has been described to be used as a longer term ‘mock-up’ with which the patient can go home (Figure 3).
Generally, the most common technique is to use a vacuum-formed splint fabricated using a stone model copy of the definitive wax-up. Flowable composite is then placed in the splint and placed over the teeth. Prior to this, petroleum jelly is placed over the teeth for easy removal of the ‘mock-up’ after its use. The composite is part cured and the excess is removed prior to definitive curing. Great care must be taken to limit composite leaking into the interdental spaces. The patient and clinician are then able to review the results (Figure 4). Photographs are taken and given to the patient and the ‘mock-up’ is removed before leaving. The splint can also be used as a tool during fixed prosthodontic preparation procedures as described by Curry in 1999.10
Advantages of this technique are that various shades of composite can be used and the results can be altered chairside to give the patient the final say in the result. The major problem with this technique is the cost involved as a diagnostic wax-up, vacuum-formed splint and composite are all needed.
Photographs of previous cases completed can also be an invaluable tool in giving the patient an idea of the final outcome. It is worth having photographs showing a range of treatment modalities and materials to review with the patient. It is also useful to show a mix of outcomes ranging from the ideal to the more realistic to prevent patients' expectations being raised to unattainable levels.
The method used widely in our department is the use of Orthocare® wax as a direct technique intra-orally. This technique has not been previously reported in any other literature to our knowledge. The technique is simply to apply the wax to a dried, clean tooth and shape it using fingers, flat plastic or Wards carver to the desired shape (Figures 5 and 6). We have found Orthocare® wax specifically has the best properties for quick, intra-oral adaptation. The patient is then able to get an insight into the treatment goals with respect to his/her own mouth and face.
The main advantage of this technique is its simplicity. It takes only a few minutes to complete, the costs are extremely low and it is an invaluable tool when discussing possible treatment options, especially at initial appointments. There are some disadvantages to this technique; specifically that it gives no insight into final shades of restorations. However, we have found that, in most situations, the shade is actually similar to the natural tooth as the wax is relatively translucent. Obviously, this technique can only be used whilst the patient is in the chair and there is no scope to try the ‘mock-up’ at home.
Again, it is possible to take an alginate impression of the intra-oral wax-up to provide a study model for future reference, if required. It is useful to take ‘before’ and ‘after’ clinical photographs to be used by the patient, clinician and technician. Some younger patients have found it useful to take photographs using their own mobile phones, so that the information is presented in a medium they are comfortable with and can access easily.
In our experience, this cheap, simple technique can often give the patient a good insight into the final outcome achievable, especially in the younger age group.
The aesthetic preview is an important part of gaining valid consent and in the treatment planning process. It is important that the patient can get an idea of the final result prior to commencing any treatment whenever this is possible. We have outlined the most common techniques employed and have shown examples of a very simple, yet effective technique using orthodontic wax which could easily be incorporated into general practice.
