April 1, 2011
by Lori Trost, DMD and Scott Schlueter, DMD, MS
As the practice of dentistry continues to move forward with the offering of improved materials and predictable techniques, the expectation of esthetics becomes a given in both the minds of the dentist and the patient. However, in the clinical setting, technical delivery and patient presentation can often impart obstacles that supersede the final treatment outcome.
Given the history of implant materials and integration of almost 50 years, current placement shares a 95% success rate.1 Capitalizing on this certainty, the focus shifts to the periodontal drape that frames the restoration. Research illustrates that although implants benefit from a high surgical success rate, this outcome does not guarantee an appealing esthetic result.2 Specific guiding principles for optimum esthetics must be recognized in order to achieve the desired end result. These parameters provide a usefulness that can guide the implant team throughout each phase of implant treatment – from the initial patient presentation, through diagnostic planning, in placement, with lab communication, and particularly during the course of restoring. Each aspect becomes increasingly more important if a patient is referred for implant placement and then returns to the original clinician for the final restoration.
This article and presented case studies will focus on suggested criteria that can assist the clinician(s) during the implant process to ensure optimum esthetics given successful bony integration.
Patient Presentation and Comprehensive Diagnosis
When the opportunity for an implant discussion arises, a comprehensive background of discovery needs to be performed on each patient. Essentially this fact finding mission directs the pathway of decision making and helps to construct the full treatment picture while lending a realistic expectation. These questions help in guiding the clinician to proceed, yield with caution, or decline treatment.
• What is the patient’s initial presentation – why is this treatment being considered? Obviously an existing or soon to be edentulous space has a history. Consider the following scenarios: an unrestorable tooth, recent extraction, perhaps an existing bridge that now can develop into individual teeth, trauma, failed or denied endodontic therapy, or even prior orthodontic treatment creating alignment in preparation for a future implant.
• Does this patient present as a good medical candidate for implant placement? What is their general overall health picture? What medications are they taking? Do they have a history of diabetes, or more importantly do they have an overall well-controlled blood sugar level which is assessed by getting a blood analysis (HBA1C should be 7)? If so, do you understand that due to less than optimal blood sugar control this implant case automatically assumes compromised healing?
• More specifically, does this patient have good dental health? What is their oral hygiene condition? What if any periodontal disease needs to be addressed?
• Does the patient display an autoimmune disease or connective tissue disorder such as Lupus or rheumatoid arthritis? Are they taking any immunosuppressant medication? Approach with caution because these presentations can delay or impair the healing process.
• Where is the patient’s smile line in respect to the gingival margin location? How would you classify their tissue type? Thin tissue biotype presents a delicate challenge compared to a thicker biotype patient.
• Does the patient possess habits that may inhibit healing or the placement of the implant? Patients who smoke seriously compromise the surgical success as well as the esthetic outcome. Has the patient’s occlusion and function been evaluated? Does the patient demonstrate parafunctional habits such as clenching or bruxing? Does the patient wear a current splint or nightguard?
Diagnostic Planning and Placement
Once the patient has been established as a good candidate for implants – decisions move to what type of implant appropriately answers the treatment or functional need while addressing the esthetic expectation of the patient. A combined effort between each participant on the implant team creates a win-win. The clinician who places the implant and restoring dentist must be in communication, as well as the restoring dentist and the lab partner must have a developed protocol for consistent results.
Success starts with excellent impressions from which a lab can begin to craft a model of the future restoration(s) and the gingival architecture. From this waxed model, an occlusal positioning stent can be fashioned to assist the clinician when the implant is to be positioned. This is a critical step that should not be overlooked. This positioning stent in combination with digital radiography or tomography ensures the tools needed for not only successful integration but proper implant placement.
Immediate placement implants present another set of considerations. The typical scenario results in a larger socket diameter than the implant that is being placed. In order to place an implant in an immediate extraction socket, it is especially important to know the bone topography of the area in the planning phase. Cone beam computer tomography (CBCT) allows the clinician to see this third dimension that traditional radiographs cannot achieve. This information will not only determine the feasibility for immediate implant placement, initial primary stability of the implant for immediate temporization, but also assist in preplanning for possible bone augmentation in the site. This visual information on a large LCD screen can be introduced to the patient for education and a higher patient acceptance. Clinical respect must be exercised when placing immediate implants in the anterior region due to the ability of the cortical bone on the facial surface to recede.3
Clinicians who are savvy creating outstanding esthetics always include their lab technician early in the implant process. As each phase of treatment passes, this partnership transfers the baton in a manner of seamless treatment. The beauty of each phase has been taken into consideration because the case began with the final product in mind and now moves forward with anticipation.
With current restorative materials, more possibilities exist for kinder materials that interface with the gingival architecture, esthetic abutments that erase a metallic grayish shadow, and improved emergence profile that creates the desired result. Digital photography is the best method in which to communicate your patient’s appearance to the lab technician. Also during the course of treatment if an extraction is performed, the tooth should be saved and sent to the lab for color and character matching.
Decisions concerning gingival contour and emergence profile now become real in the end product fabrication. Gingival defects are able to be masked. Any uniqueness to the abutment angulations is taken into consideration for improved alignment, creating enhanced “realness”.
The Healing Time
The interval of time that allows for healing of the gingival collar is crucial for esthetic success. The typical time allowed for the tissue to heal is 6-8 weeks. These healing periods are determined by the thin or thick tissue biotype of the patient, the location and aggressiveness of flap reflection of the area during the placement of the healing abutment, or temporary placement.
As we know from the literature, to develop or maintain a papillae and avoid a black triangle space, the distance from the contact point to the crest of bone must be 2-4mm.4 This clinical reality involves tremendous esthetic consequence.
This stage of treatment allows the restoring dentist to begin to create an emergence profile and persuade the gingival collar into cooperation for exceptional esthetics. Care must be taken to fabricate the transitional restoration s
o that it encourages healing as well as a “new” presentation. In the case of some patients, their originally extracted tooth or teeth may be used to create the transitional or temporary. By fabricating an ovoid transitional that is placed into the sub-gingival structure, the emergence profile can originate. Approximately every 2-3 weeks the patient should return for additional material – be it acrylic or composite, to be incremental affixed to the emerging ovoid presentation.
By the time the clinician is ready to restore the implant, the stage has been set for the final outcome. The entire implant team can proceed with confidence knowing that the final esthetic result has been respected by the use of predictable and reliable principles.
Whether the final preference is a screw-retained or cemented restoration, each offers their own benefits.
When delivering the final restoration, an occlusal analysis should be performed to make certain that the occlusion is in balance and harmony. Final treatment consideration should be made in response to any parafunctional habits the patient may display by fabrication or a splint or nightguard.
Case Study #1
A 37-year-old female patient presented with full coverage porcelain fused to metal crowns (over 12 years old) on her maxillary central teeth that had undergone endodontic therapy. Her initial complaint was “they feel funny when I bite” and they had “puffy” gums. Radiographic exam revealed these teeth had undergone endodontic therapy, were restored with posts and crowns, and pathology was present around the root surfaces. These teeth were condemned and the patient was deemed an ideal candidate for implants (Fig. 1). A comprehensive survey as discussed above was given to the patient. Due to the need for optimum esthetics in the anterior region combined with the challenge of root resorption and/or pathology, the decision was made to refer the patient to a periodontist for implant discussion.
The patient agreed to the treatment of extracting both maxillary central teeth and placing two immediate load implants in those spaces.
The patient presented on the day of surgery with tooth #21 crown fractured off. There was a parulis noted on the facial of #11 indicating facial bone loss due to the local infection (Fig. 2).
Teeth #11 and 21 were atraumatically extracted and initial implant osteotomies were performed (Fig. 3). To avoid interproximal implant bone loss, the osteotomies were confirmed that a minimum of 3mm will be between the implants.4,5 Next, guide posts were placed in the osteotomies (Fig. 4). Radiographs were taken to verify the tentative implant positions. After verification, the two Nobel Active Implants (Nobel Biocare) were placed and torqued in over 35ncm, allowing immediate temporization. Figure 5 illustrates the immediate temporization of both teeth. Verification was made certain that no occlusal contacts or interferences were on the temporaries and the adjacent teeth protected the temporaries in excursive movements.
After five months of healing and integration time, the patient returned to the referring dentist for the transitional phase. Ovoid style transitional healing abutments were created to encourage a natural emergence profile. Care was taken to highly polish the sub-gingival surfaces for tissue acceptance and formation. The patient was seen again 6 weeks later to undergo another addition to the ovoid abutments. During this time the patient was instructed to rinse with 2% Chlorhexidine and to begin gentle flossing between the transitional implants. Patient compliance is critical during this final healing and development phase for papillae formation.
One month later, final impressions were taken using an open tray, two step impression technique utilizing a polyvinylsiloxane heavy body/light wash materials. (Take 1 Advanced; Kerr) Several digital pictures were taken to communicate the shade selection and teeth texture with the lab. Lithium disilicate crowns – IPS e.max (Ivoclar) were fabricated. The patient returned in two weeks later for delivery of her new crowns which were tried in, occlusion adjusted, and then cemented using RelyXTM Unicem (3M ESPE). The patient was very pleased with her final result with special notice given to the symmetrical harmony, papillae architecture and gingival framework (Figs. 6 & 7).
Case Study #2
A 37-year-old male patient presented with a non-savable maxillary right central tooth due to a root fracture. The patient was referred to an oral surgeon for extraction. Prior to the extraction, an impression was made so that an immediate removable transitional appliance could be inserted upon extraction to replace the newly missing #11. Contrary to the authors’ protocol, an implant discussion ensued at the extraction appointment leading to an immediate placement implant. Figure 8 shows the implant radiograph. Unbeknownst to the patient, the treatment proceeded and the final result is shown in Figure 9. Notice the labial plate resorption demonstrating a less then desirable final effect. This case clearly demonstrates that although the implant integration was successful, the esthetic outcome was not.
Case Study #3
A 34-year-old female patient presented with a non-restorable, sub-gingivally fractured and temporized left maxillary central incisor. The decision was made to extract the tooth. Prior to the extraction an impression was made so that an immediate transitional appliance could be delivered if primary stability was not achieved. Four months expired and the patient was referred to a periodontist for implant placement.
This case presented several challenges in that the ridge dictated the implant placement as well as the angulation of the abutment. Due to the high smile line, the emergence profile and gingival drape were especially critical in achieving smile harmony and proper proportions (Fig. 10). Prior to implant treatment, it was discussed with the patient that, due to the adjacent crown margin visibility along with shade discrepancy, it was recommended that #11 and 22 crowns should also be remade when #9 was restored.
Special care was taken in the extraction to avoid facial bone plate loss. The socket was curetted out to remove all residual cyst tissue. Measurements were made from the free gingival margin to the boney crest in the mid buccal and palatal along with the mesial distal locations (Fig. 11).
The implant osteotomy was placed palatally to attain primary stability and exited slightly facial to the adjacent incisal edges to allow for immediate temporization and clearance of occlusion and excursions during the healing phase (Fig. 12).
A Nobel Active implant (Nobel Biocare) was placed with a torque value of over 35ncm and then a temporary abutment was placed and the pickup temporary base cap was placed on the abutment (Fig. 13). The polycarbonate temporary crown was placed with auto curing jet acrylic contouring the inside and then positioned on top of the temporary base cap. The temporary acrylic was allowed to set and final adjustments were made (Fig. 14). Care was made to create a very smooth final polish and then it was then cemented with limited temp bond cement. Protected occlusion was verified on the crown with no interferences.
At the beginning of treatment, initial impressions, digital photographs and the extracted tooth were given to the lab in preparation for the transitional insertion and final restoration. The lab technician fabricated a positioning jig from rigid bite registration material for proper positioning of not only the transitional but for the final restoration. Figure 15 shows the final radiograph and Figure 16 is a 2 year post treatment photograph. The patient now would like to move forward and replace crowns on the adjacent teeth to create a consistent appearance.
The success of the final implant restoration is measured not only by inte
gration, but absolute esthetics. Both of these considerations depend on definitive choices that must be respected in order to achieve a predictable outcome, or consequences from poor selection will create a less than desirable result. By respecting each unique clinical case and its presentation, implant aesthetics can become more predictable by following specific protocol and guiding parameters.OH
Lori Trost maintains a private practice in Columbia, IL merging contemporary esthetic dentistry with a minimally invasive approach to patient care. Dr. Trost has authored a variety of articles in JADA, DPR, Oral Health, Dental Economics, and WDJ, as well as several manufacturers’ publications. She lectures on a regular basis throughout the United States and Canada. Her lecture topics range from current cosmetic techniques and materials, minor tooth movement, to practice management and team building.
Scott R. Schlueter graduated dental school from the Southern Illinois University of Edwardsville, School of Dental Medicine. Joined the United States Air Force and completed an advanced education in dentistry residency 2000. He received his masters and periodontal certificate at the University of Texas Health Science Center at San Antonio. Dr. Schlueter has served as a faculty adjunct at the University of Texas Health Science Center along with the VA hospital located in San Antonio. He is a Diplomat of the American Board of Periodontology, a member of the American Dental Association, American Academy of Periodontology, Academy of Osseointegration. He maintains a full time private practice limited to Periodontics and implants, in St. Louis, MO.
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