Immediate Implant and Immediate Temporary Acrylic Crown in the Aesthetic Zone: A Case Report

Immediate Implant and Immediate Temporary Acrylic Crown in the Aesthetic Zone: A Case Report
By Jack G. Zosky, DDS, FRCD(C), FICD and Allan P. Schaffran, DDS
March 2004
Oral Health Journal
ABSTRACT: Historically the traditional two-stage approach to implant success utilizing the Bran?¥mark protocol emphasizes a load-free healing period as a major requirement for predictable implant integration. A single stage surgery by placing a non-submerged implant has also been shown to be successful but may be unpredictable as far as aesthetics is concerned. Technological advances in implant surface characteristics to enhance roughness and porosity demonstrate better and faster bone adaptation. Immediate loading has been proposed for the anterior aesthetic zone. With careful patient selection and attention paid to available bone and implant positioning this technique has been shown to be successful and advantageous for the patient.
DISCUSSION
Research Data
Although treatment outcome studies utilizing immediate implant placement and immediate load in the anterior aesthetic zone are limited, the preliminary data are promising.9,13-15
The most comprehensive of these is Groisman et al where 92 implants were evaluated in a prospective manner with life table analysis up to two years in function. Six of the 92 implants failed and the remaining 86 successful implants showed no soft or hard tissue adverse reactions. This success rate of 93.5 percent is comparable to data involving the more traditional two-stage, non-loading protocol of Bran?¥mark. One of the six failures was attributed to trauma sustained one day prior to surgery, which intruded the tooth and caused fracture to the buccal bone. Two of the other failures were attributed to overloading due to 100 percent overbite, which should be a contraindication to this technique. Therefore, only three of the six failed implants had no obvious reason for failure.
Implant Design and Surgical Technique
Implant surface "roughness" enhances bone to implant interface. Also a taper design or true anatomical root shape can compress bone of lesser density for better primary stability and can optimize stresses transmitted to bone.
The surgical protocol includes avoidance of a surgical flap so that bone vascularization is not compromised. Also, papillary form is maintained. Careful, atraumatic extraction is essential. The use of a surgical guide ensures proper implant positioning. The surgeon's finger should palpate the buccal gingival wall to "feel" for possible perforation. The initial drill should rest against the palatal wall of the socket to avoid thinning of the buccal plate and a probe can be used to check the integrity of the buccal wall during osteotomy finalization.
If the bone feels fragile with little resistance to the initial drill then osteotomes can be used to compact the bony housing.
Provisionalization
The peri-implant soft tissue envelope can demonstrate recession of approximately 0.6mm to 1.0mm and generally occurs within three months after implantation. Therefore, the temporary acrylic crown should be left in place for at least three months prior to fabrication of the final restoration. During this provisional period there should be no occlusal contact in centric occlusion or excursive movements. This provisional timeframe also allows for manipulation of the soft tissue emergence profile and papilla reformation.17
CONCLUSION
Successful and predictable achievement of immediate replacement of a single tooth via implant insertion and provisionalization with a temporary acrylic crown has become an acceptable procedure. This is particularly desirable in the anterior maxillary aesthetic zone where the essential demands of hard and soft tissue preservation must be optimized. It allows for simplification of treatment and elimination of protracted time sequences. It also provides the obvious psychological advantage to the patient and enhances patient comfort. Most importantly, the ultimate aesthetics of the final restoration can be more predictably attained.
However, the multi-faceted aspects of this surgical/prosthetic treatment present a daunting challenge to the surgical/restorative team. They should be very experienced with all aspects of implantology and especially cognizant of the criteria for success with this technique. There should be careful collaboration between surgeon, restorative dentist and lab technician as well as the patient.
It should be remembered that the maintenance and preservation of existing anatomical structures is easier that re-creating them once lost. No doubt further progress in implant design will be forthcoming as well as surgical instrumentation to enhance implant stability. In fact a new "scalloped" shoulder design of the Nobel PerfectÇ—¢ (Nobel Biocare Yorba Linda, CA) implant has been utilized by the authors with very promising results.