Tooth replacement is a significant issue in the World. Such replacement is considered important by patients to improve aesthetics, function and quality of life. Tooth replacement is therefore a significant issue. Resin-bonded bridges (RBBs) are conservative and cost-effective tooth replacement option that involves minimal tooth preparation and are secured in place with an adhesive cement by bonding to the outer enamel layer of the tooth. Clinical reports of these prostheses at the University of Hong Kong shows some of the highest success rate and greatest longevity in the dental literature. However, a problem with this type of prosthesis in that it still needs some tooth preparation to accommodate the framework thickness of the bridge. In some patients with tooth wear, this may mean cutting through the enamel crown down into dentine which will weaken the tooth. In light of the tooth preparation some patients will refuse this treatment, in particular patients with dental drill phobias.

The aim of this study is to investigate RBBs with tooth preparation and with no tooth preparation for the replacement of single missing teeth in a randomized controlled trial. However, a significant consequence of a no preparation RBB will mean that after cementation the prosthesis will interfere with the patient's bite, making the bridge prosthesis stand high. This will take time for the patient's original occlusion to re-establish itself by the movement of the tooth supporting the bridge. Despite the success of "supra-occluding" restoration has been reported in some studies, currently neither no preparation nor supraoccluding dental bridges are the standard of care for general dental practitioners and have not been reported on as a clinical trial in the literature. Most symptoms reported for supraoccluding restorations were transient and are reversible. The findings of this research will have significant impact on the teaching and practice for clinical prosthodontics and patient care worldwide. Patients will have a dental prosthesis that requires no dental drilling, no local anaesthetic and will have a stronger tooth supporting the bridge that should have greater longevity. More patients, in particular phobic patients will therefore seek treatment for tooth replacement with this conservative treatment option.

Inclusion Criteria:

1. 15+ years old
2. A complete bite on the supporting abutment tooth
3. At least one missing upper incisor
4. Controlled dental disease - no active caries or periodontal diseases
5. A minimum of 12 occluding pairs of natural teeth
6. Patients will be available to be clinically reviewed up to 3 years

Exclusion Criteria:

1. Patients with uncontrolled active tooth decay or periodontal disease (i.e. 5+ mm probing depth and bleeding on probing).
2. Patients with teeth missing opposite to the planned RBB
3. Abutment tooth mobility of 2 or greater (Millers classification)
4. Patients with debilitating illnesses or complicating medical conditions
5. Heavily restored tooth abutment not suitable for an RBB
6. A supporting abutment with an open bite