Restoratively Driven Implant Dentistry
Methods and considerations for the general practice dentist
Dave King, DDS
There is a growing demand for dental implants. The average adult between 20 and 64 years-of-age is missing three teeth. For those age 65 years and older, that number increases to nine missing teeth.1 The average general dental practice likely has hundreds to thousands of patients who need dental implants.
Although there are several alternatives, the endosseus dental implant generally affords the best long-term prognosis.2,3 A single tooth dental implant can have a higher initial out-of-pocket expense than a bridge or denture; however, over a lifetime, the costs associated with an implant can be much less expensive when compared to a fixed bridge that replaces one tooth.4,5,6,7
Implant Placement Training
There is significant conjecture among dental providers regarding who should be performing implant surgery and what training is necessary.8,9 Beyond the classes that are taught during residencies and predoctoral dental programs, available implant training programs include weekend courses, weeklong courses, and multiple weekend courses. Many of these courses are sponsored by manufacturers or supply companies.10 Care should be taken to select a course that provides adequate training in a supervised setting. Hands-on training with direct clinical cases overseen by program administrators is crucial.
Many general practice (GP) dentists refer implant placement to a periodontist or oral surgeon; however, there are also many GPs who are capable of placing implants and completing the necessary bone grafting. Regardless of who places the implant, when risk factors are controlled and patient expectations managed, implant placement can yield an excellent prognosis.
Methods for Implant Placement
The standard method for implant placement involves placing the implant then allowing several months for osseointegration, after which restoration can occur. Several studies demonstrate a better long-term outcome if the implant is allowed to heal unloaded beneath the gingival tissues, while others seem to indicate that immediately loaded dental implants can exhibit faster bone maturation.11,12,13
Two methods exist for surgical delivery of the dental implant: freehanded or non-guided placement and guided placement. Freehand placement requires appropriate radiographic planning and preparation, but is generally much more time efficient.
Comparatively, guided surgery requires more initial treatment planning, unique radiographs, and additional lab communication for the fabrication of the surgical guide, but can allow for a much simpler surgical appointment.14,15 The surgical guide needed for a guided surgery procedure can be fabricated in either the dental office or the lab. Interestingly, many providers who use the guided technique report less procedural stress associated with implant placement.
Implant Surgery Considerations
The risks associated with implant placement include total failure, unusable restorative position, and nerve anesthesia/paresthesia.16 These risks exist regardless of which technique is employed for placement or who is placing the implant.
The clinician should closely adhere to accepted standards of care and surgical placement protocols, including timing of placement and whether or not bone grafting is appropriate. Many different bone graft materials exist, so the clinician should be cautious when selecting an appropriate grafting medium. Alternatively, an implant can be placed after the extraction site has been allowed to heal without the use of a dental bone graft.
Sinus augmentation is sometimes required to facilitate maxillary molar implant placement. This is often referred to specialists, but can be completed by the competent GP. Care should be taken to evaluate whether or not it is appropriate to place an implant at the time of sinus augmentation.17 Sinus lift protocols require a longer healing time for the sinus graft material to integrate prior to placement or loading of the implant.18
Post Implant Surgery Care
Healing protocols vary from case to case and can range from 2 to 6 months, depending on whether or not a bone graft was placed. Prior to restoration (whether analog or digital), the healed dental implant must also be uncovered for torque testing and impression.19
Completing the Final Restoration
While immediately loaded dental implants are an attractive treatment offering, the GP must be cautious and appropriately explain all of the potential risks and longevity issues should the treatment fail to go as planned or if the restoration needs future revision and maintenance.
Many clinicians will complete the impression at the time of uncovering, while others prefer to wait for the gingiva to recover from the surgical exposure. Digital impressions can be used to acquire the necessary restoration data using any of the available intraoral scanners. Research supports that digital impressions have a much higher degree of accuracy than analog techniques.20,21 Of note is the CEREC® CAD/CAM system (Dentsply Sirona), which enables the clinican to use a scanning body to digitally capture an impression of the implant location and surrounding tissues. This is then used to design the implant restoration.
There is great time and cost savings to be realized in using CAD/CAM technology. Scanning can be done at the time of uncovering, and delivery of a single tooth restoration can be completed at the same appointment. Using a TiBase (Sirona) and the appropriate e.max restoration (Ivoclar Vivadent), a permanent dental implant restoration can be completed for as little as $150 (for a screw retained hybrid abutment crown), which is significantly less expensive than spending several hundred dollars per unit from an outside dental lab.
Case Presentation
An adult male presented with a non-restorable molar (Figure 1). After evaluation, we decided to move forward with extraction of tooth No. 14 and immediate implant and bone graft placement. A CBCT scan was taken for surgical guide fabrication (Figure 2), and the surgical guide design was accomplished digitally via GoToMeeting™. After anesthesia, the tooth was decoronated and sectioned, and the osteotomy site was prepared using the surgical guide. The tooth roots were elevated and removed, and an implant was placed (NobelActive® 5.0x10mm) into the prepared osteotomy in the immediate extraction site. Next, 1cc of creos™ (Nobel Biocare) cortico-cancellous 0.25mm to 1mm bone graft material was condensed into the root crypts and the site was closed with vicryl sutures and a collagen membrane (Figure 3 through Figure 5). After 2 months of healing time, restoration was completed with an NBA 5.0L TiBase (Nobel Biocare) and an e.max A3 LT abutment block (Ivoclar Vivadent) (Figure 6 through Figure 10).
Conclusion
Dental implant placement is the standard of care for the replacement of missing teeth. Each patient’s risk factors must be managed, and referrals should be made when appropriate. When deciding between the free-hand placement or guided surgical placement of dental implants, caution should be exercised with a focus on what is in the patient’s best interest. In addition, the timing of the steps involved in each restoration should be carefully considered. When acquiring an impression, both analog and digital techniques can yield high quality restorations. Digital design processes enable the clinician to create high quality restorations in as little as one appointment, creating substantial cost savings for the practice and significant time savings for the patient.
References
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About the Author
Dave King, DDS
O’Fallon Modern Dentistry
St. Louis, Missouri
