Implant Provisionalisation
Kyle D. Hogg
Principles
The success of dental implant rehabilitation cannot be entirely measured by implant and prosthesis survival, but rather must incorporate additional elements such as dento-gingival aesthetics, prosthesis aesthetics, functionality, phonetics, maintenance of the soft- and hard-tissue health of the surrounding dentition, rate of mechanical complications, rate of biological complications and overall patient satisfaction. This is of particular importance when providing treatment in the aesthetic zone, where the demand for a harmonious and visually pleasing replacement for missing teeth is at a premium. Numerous surgical protocols, implant designs, abutment designs and restoration designs have been developed to provide treatment outcomes that satisfy the aesthetic and functional requirements of replacing missing maxillary and mandibular anterior teeth.
An important element in performing predictable and aesthetic implant restorations in the aesthetic zone is provisionalisation. Provisional restorations have a variety of purposes in relation to implant dentistry. These restorations allow for acceptable patient comfort, aesthetics and function during the treatment process, while maintaining occlusal stability and the position of adjacent or opposing teeth. Provisional restorations provide a template for peri-implant soft-tissue contouring and development of an ideal emergence profile, critical factors in the overall appearance of the final restoration. These restorations allow for a trial of the proposed restorative prototype, providing an opportunity for critical appraisal and alteration of the aesthetics and function of the provisional restoration intra-orally. Once approved by both patient and clinician, provisional restorations can be utilised to transfer important design information to the dental technician for use in fabrication of the definitive restoration.
Providing appropriate provisional restorations during the course of implant rehabilitation can be a challenging and time-consuming aspect of clinical treatment. Provisionalisation can be divided into three phases: provisionalisation prior to implant placement; provisionalisation after implant placement but before placement of an implant-supported provisional restoration; and implant-supported provisional restoration.1 Some patients may not require all three phases of provisionalisation, depending on the timing of implant placement relative to the loss or agenesis of the tooth to be replaced, the preferences of the individual patient and the loading protocol chosen for that implant. Selecting the appropriate provisionalisation strategy for the patient should be based on the specific clinical presentation and preferences of that individual.2 It is important to have a clear understanding between the patient and clinician regarding the cost, limitations and duration of the provisional restorations, as well as the therapeutic benefits of the process.
There are three broad categories of provisional restorations available for use during the course of treatment: removable prostheses; fixed tooth–supported prostheses; and implant-supported prostheses.3 Refer to Table 11.5.1 for a review of the relative advantages and disadvantages of each provisionalisation strategy.
Table 11.5.1 Provisionalisation strategies for implants in the aesthetic zone
Restoration type | Removable | Fixed (tooth supported) | Implant supported |
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Criteria |
Interim |
Essix |
Bonded |
Resin-bonded bridge (metal wing) |
Reinforced provisional FPD (metal, fibre) |
Acrylic resin provisional FPD |
Implant- retained provisional restoration |
Durability | Good | Poor | Fair | Good | Good | Fair | Excellent |
Modifiability | Easy | Moderate | Moderate | Moderate | Moderate | Easy | Easy |
Aesthetics | Good | Fair | Fair | Good | Good | Good | Excellent |
Comfort | Poor | Fair | Good | Good | Good | Good | Excellent |
Hygiene | Easy | Easy | Difficult | Moderate | Difficult | Difficult | Easy |
Function | Poor | Poor | Fair | Good |