October 18, 2016
by Daniel Kobric, BSc, DMD, MSc (Perio), FRCD(C)
Achieving ideal esthetics in addition to restoring the patient’s function is every clinician’s goal. Successful outcomes in restorative dentistry are well documented in publications and readily displayed in practice promotional materials. Although most patients are happy with the treatment outcomes, achieving highly esthetic result can be challenging in implant dentistry. Successful implant integration does not equate with a beautiful smile. While the clinically/functionally successful cases are often displayed or exhibited in journals or lectures the esthetic failures are not. The usual suspects for poor cosmetic outcomes have been postulated to be: occlusion, previously grafted sites, implant brand, implant position (labial/supra-/subcrestal), tissue type, tissue volume (hard and soft), time of loading (early vs. late), intrinsic and extrinsic factors (diabetes and smoking, respectively) and any combination of these and perhaps others as of yet not documented. The root of the problem lies in the fact that implants and their prosthesis are an artificial means of replacing a natural root and tooth. The requirement for a successful implant-retained prosthesis differs from the natural dentition. Since the decision to proceed with tooth removal includes periodontal, endodontic and traumatic events that invariably leave the prospective implant sites deficient in more than one way. The lack of favourable bone volume can create insurmountable hurdles even after multiple and/or complex bone grafts, ridge preservation techniques and soft tissue augmentations. The esthetic expectations of our patients are high, and may sometimes be unrealistic especially if the already integrated implant display signs of clinical failure (such as inflammation, infection, exposed threads). Treatment protocols for the management of the esthetic failures are also difficult to find in the literature as these are often presented as case studies. However, as clinicians it is our role to help resolve the chief complaint of our patients by using the best evidence available. By and large the practitioner and patient have three options to consider following an esthetic failure: Acceptance of the status quo, explantation (implant removal followed by site development and secondary implant placement, if possible) or hard and soft tissue augmentation around the existing implant followed by revision(s) of the existing prosthesis or fabrication of a new prosthesis.
In consultation with our patients, a balance between these choices has to be struck based on the chances of success and the amount and/or invasiveness of the intervention(s) required correcting or improving their oral health. The case report presented below is one that required multiple interventions and a great deal of patience from the patient.
A 38-year-old woman was referred for a periodontal assessment of a dental implant at the right maxillary lateral incision position. She reported discomfort and bleeding while performing routine oral hygiene. The discomfort increased since the time of implant placement. The following history of the 1.2 site and radiographs were provided by the treating dentist: trauma to the anterior teeth many years ago resulted in chipped crown and a root canal treatment; many years later, pain was reported and the extraction of an upper right lateral incisor with a chronically infected root canal treated tooth (Fig. 1) was required. An immediate implant (Osseotite NT Certain Implant 4 mm (D) X 13 mm (L); 3i) was placed with bone grafting (Dynagraft II Putty 1 cc; Citagenix) (Fig. 2). After a healing period of 5.5 months, a second stage surgery was performed with a pick up impression for a crown and UCLA abutment. A healing abutment was placed to allow for tissue healing. Two weeks after the impression was taken, the crown was inserted. The treating dentist noted slight mobility upon tightening of the abutment. The crown was cemented with temp bond. Sixteen days later the patient returned and a diagnosis of a failed implant was made. Seven months after the original implant was placed, it was removed. A larger implant (Osseotite NT Certain Implant 5 x 13 mm; 3i) was placed and a provisional crown was placed (Fig. 3). Following six months of healing, an impression for an implant-supported crown was made. Two weeks later, the abutment was torqued to 25 Ncm and the final crown was inserted and cemented with temp bond.
Tooth 12 chronic apical periodontics.
Immediate implant 4×13 mm (31).
Second implant 5×13 mm (31).
A second dentist referred the patient to the author eight and a half years after the second implant was placed. The reason for referral was for considering an esthetic grafting and/or bone augmentation to improve the cosmetic appearance. A clinical examination of the area began with an examination of the smile line, which was moderately high with papilla and marginal gingival showing (Fig 4). The implant-supported crown did not match with the site in color, contour and shape. A closer examination of the 1.2 site revealed inflammation surrounding the 3 mm of exposed titanium apical to the crown margin. An absence of keratinized tissue and a Siebert class 1 defect was observed (Fig. 5). The soft tissue surrounding the implant platform was observed to be mucosa. The labial surface of the crown appeared to be over contoured and there was a depression at the papilla distal to the crown (Fig. 6). Probing of the area revealed generalized 2-3 mm depths with bleeding upon probing at the implant site. The patient indicated tenderness to light pressure in the area of the implant. A periapical radiograph demonstrated that there was bone loss to the 2nd thread on the implant body (Fig. 7).
Facial view of 12 site.
Incisal view of 12 site.
8.5 years after second implant placed; bone loss to second thread.
The treatment options presented to the patient were to either remove the dental implant followed by hard tissue grafting for the possible placement of a third dental implant, removal of the implant with ridge reconstruction and placement of a three unit bridge or to try and rebuild the soft tissue around the existing dental implant which would necessitate the fabrication of a new crown. The risks of each option were reviewed and the patient opted to try and save her current implant while attempting tissue augmentation(s) without having to remove the implant. It was explained that several procedures would be required to restore and supplement the missing tissue volume and to cover the exposed portion of the dental implant.
The patient’s dentist fabricated an interim partial denture to be used following removal of the crown. After anesthetizing the area, the cemented implant crown was removed (Fig. 8) and a cover screw (0 mm) was placed (Fig. 9). Under local anesthesia, the soft tissues were probed and revealed probing depths of 4 mm at the mesial and 5 mm at the distal of the 12 implant. The area was debrided with hand and piezo scalers. The denture was inserted and adjusted by her dentist. Following one-week of healing, there was some resolution of inflammation and the true nature of the problem was visualized: the implant body was labial in position with the head (prosthetic platform) of the implant at the edge of the labial vestibule. Additionally, the first thread could be seen supragingivally (Fig. 10).
Access to screw on labial of cement retained crown at 12 site.
Crown removed and cover screw placed.
One week following crown removal and debridement.
Soft Tissue Grafting
Limited labial tissue volume necessitated the placement of soft tissue graft. An onlay graft was utilized in an attempt to build volume of tissue circumferentially around the exposed implant. Briefly, the tissue at the 12 site was de-epithelialized (Fig. 11) and tissue was harvested from the residual ridge corresponding to the edentulous 17 site (Fig. 12) and secured with resorbable chromic gut 4-0 and 5-0 sutures at the 12 site (Fig. 13). Healing was noted at 1 week (Fig. 14). Two and four weeks later moderate amount of keratinized tissue was also gained at the labial surface (Figs. 15, 16 respectively). However, it was not successful in fully covering the exposed implant.
Recipient site de-epithelialized for onlay graft.
Harvest of 17 site ridge for only graft.
Onlay graft sutured to 12 recipient site.
One week post op of onlay graft.
Two weeks post op of onlay graft.Four weeks post op onlay graft.
Four weeks post op onlay graft.
Connective Tissue Grafting
The defect at the labial surface also included a tissue volume discrepancy. For this a connective tissue graft was utilized to help bulk up some of the tissue. It was also necessary to increase the tissue volume for further grafting. Briefly a split thickness flap/pouch was created at the 12 site. The harvested graft was sutured and periacryl (Glustitch Inc.) was placed (Fig. 17) and allowed to heal for seven weeks (Figs. 18, 19).
Connective tissue graft placed.
Two week post op.
Seven week post ops; note scar in mucosal tissue.
The tissue matured to the point where the next phase of treatment required the fabrication of a temporary crown. The cover screw was removed and the tissue was assessed. A split thickness flap was made apical to the cover screw (Fig. 20) and the tissue was sutured coronally to the band of keratinized from tissue atop the cover screw (Fig. 21). The band of keratinized tissue atop the cover screw was then transposed labially (Fig. 22) and sutured at the labial surface with chromic gut sutures (Fig. 23). A provision angulated post (4.1 mm- 15° performance Post, IPAPF454, 3i) was placed (Fig. 24) and a prefabricated stent was used to help shape the temporary crown (Figs. 25, 26, 27). After 2 weeks of soft tissue healing was allowed to occur, a fenestration in the tissue appeared (Fig. 28). Disinfection of the site with tetracycline and a coronally positioned flap (Fig. 29) were unable to resolve the soft tissue fenestration.
Split thickness Labial flap.
Coronally positioned split thickness flap.
Apically positioned keratinized tissue from atop the cover screw.
Tissues sutured below the cover screw.
Placement of the provisional post.
Fabrication of the temporary crown.
Placement of the temporary crown.
Finalized temporary crown.
Two weeks post temporary crown placement and tissue repositioning.
Site debrided and placement of the tetracycline slurry.
Gingival Grafting and Coronally Positioned Flap
The last stage of treatment before the fabrication of a new implant-supported crown was to place a gingival graft. The purpose was to close the fenestration (Fig. 30) and add more keratinized tissue. Techniques for gingival grafts have been previously described. The donor material was harvested from the right hard palate and was sutured into position apical to the fenestration (Fig. 31). Unfortunately the fenestration remained, albeit smaller (Figs. 32, 33). Following healing (Fig. 34), the thicker band of tissue was coronally positioned (Fig. 35) with the use of silk and chromic gut sutures. The tissue response was favorable (Fig. 36) but there was still about 0.5 mm of metal showing after a further 2 weeks of healing (Fig. 37). The patient did not wish to have any further treatment to cover the exposed metal surface.
Site prepared for gingival graft apical to fenestration.
Gingival graft sutured apical to fenestration.
One week post graft placement.
Two weeks post graft placement, fenestration still present.
Split thickness flap including the gingival graft, tissue coronal to fenestration removed.
Coronally positioned flap.
Two week post op showing tissue healing.
Four week post op showing 0.5mm.
The restorative dentist fabricated a new crown and based on the esthetics of the area decided to apply a pink porcelain margin. She returned to the periodontal office for photos to be taken and for oral hygiene instruction. The patient indicated that she no longer had any pain with brushing the area and that the bleeding subsided as well. She indicated that she was very pleased with the outcome. Following the treatment, the mucosa was replaced with keratinized tissue (Fig. 38), the Siebert defect was corrected (Fig 39) and the papillae appear to be symmetrical between the left and right lateral incisors (Fig. 40).
Final crown placed – labial view (note pink porcelain at gingival margin).
Final crown placed – incisal vive (note correction in soft tissue profile from initial).
Symmetry between 12 implant crown and contralateral lateral incisor.
The challenges presented here include the treatment time frame of 13 months from initial surgery to final crown, the multiple surgeries and office visits, the unsuccessful and partially successful treatment outcomes following each surgical procedure. The factors that led to the initial problem may be related to implant size (5 mm platform at the lateral position), the labial placement of the implant, and the lack of keratinized tissues, crestal bone loss following the initial implant failure.
This case presentation documents a complex treatment utilizing multiple procedures, long healing times, hours of chair time, high surgical skills and a fully informed and cooperative patient. It emphasized the need to proper pre-placement treatment planning of the implant team in the hope to reduce the risks of unfavorable outcome. OH
The author would like to thank Dr. Peter Birek for his help and guidance with this manuscript.
Dr. Daniel Kobric is a specialist in Periodontics. He lectures at the University of Toronto and maintains a private practice in Barrie, Ontario. He can be reached at: email@example.com
Oral Health welcomes this original article.