Systematic Risk Management: Providing a Patient the Smile She Long Desired

Ali Afshar, DDS, CAGS

Abstract: The patient described in this case had medical issues that increased her risk for restoration failure. She also had long been disappointed with her smile and the overall appearance of her teeth. The goal of managing risks and achieving improved quality of life with an esthetic and functional restoration involved preventive strategies, use of a transitional immediate denture, maxillary arch implants, and, finally, a fixed, detachable, implant-supported final restoration. The keys to restoring to the patient a satisfying, beautiful smile were systematically managing the risks and improving the prognoses in each of the four dental categories—periodontal, biomechanical, functional, and dentofacial.

A 65-year-old woman was referred for a comprehensive examination and evaluation. Her concerns included the mobility of her maxillary teeth, the failing bridge in quadrant I, and her inability to chew and function efficiently. She had never been happy with her smile and the appearance of her teeth (Figure 1 and Figure 2).

Patient History
Medical History

The patient was a controlled asthmatic who had experienced severe gastroesophageal reflux disease (GERD) over the past 11 years and was currently under the care of a physician. She was a controlled, type II diabetic with an HgA1c value of 6.4 at the time of examination and, in addition to GERD, was also being treated for hypertension, depression (SSRI), and high cholesterol. She had an episode of congestive heart failure in 1996. She was classified as ASA III and was considered to possibly have a higher potential for complications with dental implants due to her dental and medical history and age.¹

Dental History

The patient reported a dental history that included extraction of her wisdom teeth. Over the previous several years, chips and pits present in her teeth had been repaired with direct composite restorations. The dental history included tooth loss due to breakdown and periodontal disease. The maxillary teeth had been moving and becoming looser over time. The missing posterior teeth had compromised her ability to function. She had been visiting her general dental office for routine dental examinations, prophylaxis, and maintenance.

Diagnosis, Risk Assessment, and Prognosis

Periodontal: The patient was diagnosed as AAP type III based on clinical and radiographic findings (Figure 3 through Figure 7). The examination revealed generalized moderate horizontal bone loss. Teeth Nos. 7 through 10 had class II+ mobility with severe fremitus in function due to secondary occlusal traumatism. Probing depths between 5 mm and 7 mm with bleeding on probing were noted. The other maxillary teeth, including the fixed partial denture, had class I+ mobility with probing depths ranging between 4 mm and 6 mm with bleeding on probing. Tooth No. 14 presented with class I furcation involvement. The mandibular arch had generalized moderate horizontal bone loss, and anterior teeth had + mobility with probing depths of 4 mm or less and slight bleeding on probing.
Risk: Moderate
Prognosis: Poor

Biomechanical: A long history of exposure to intrinsic stomach acid had resulted in moderate erosion of all maxillary teeth and the mandibular posterior teeth (Figure 8). The most severe damage was noted on the lingual surfaces of the maxillary anterior teeth (Figure 9). The upper third molars were impacted. Decay was noted on teeth Nos. 7, 9, 11, and 14. Many of the posterior composite restorations were defective, with erosion damage at the interfaces. Recurrent decay and compromised crown margins were found on teeth Nos. 4 and 6, giving them a poor restorative prognosis.
Risk: High
Prognosis: Generally poor, but hopeless for the teeth with decay

Functional: The patient reported muscle fatigue and difficulty chewing, especially with harder foods. She was aware that teeth had been moving and her bite had been changing over the past several years. She also reported an awareness of clenching and squeezing her teeth together at night.

Although both load testing and immobilization tests of the temporomandibular joints (TMJ) were normal, a slight click of the right TMJ was noted upon opening. Additionally, there was tenderness in the right masseter muscle. Her maximum opening was within normal range, and there was no deviation on opening.

The functional diagnosis was occlusal dysfunction. It is important to note that the movement of maxillary teeth as a result of periodontal disease was a shared risk factor with occlusal dysfunction and accelerated the occlusal changes. The clinical impression suggested occlusal overload as the main cause for cement washout and decay observed under the bridge abutments in quadrant I.
Risk: Moderate
Prognosis: Fair

Dentofacial: The patient presented with medium lip dynamics, with minimal gingival display at her broadest smile. Moderate maxillary gingival asymmetry and disharmony were noted. It was determined that lengthening tooth No. 9 by 1 mm would be the most esthetic position for her maxillary incisal edge. She had also expressed a desire to reduce the width of her anterior diastema.
Risk: Moderate
Prognosis: Fair

Treatment Goals
The treatment goals were as follows:

Manage the periodontal risk by eliminating teeth with poor long-term prognosis, along with stabilization and maintenance of the remaining teeth.

Manage the biomechanical risk and improve the prognosis by either removing or restoring the structurally compromised teeth.

Utilize minimally invasive, conservative tooth preparation designs wherever possible in an effort to minimize any further structural compromise to the teeth.

Manage the functional risk by treating the occlusal dysfunction and establishing a stable position of maximum intercuspation (MIP) with bilateral simultaneous and equal intensity contacts.

Establish horizontal symmetry of the maxillary gingival architecture.

Meet the patient’s esthetic desires and provide her with, as she said, “a smile that I never had.”

Treatment Plan

During the orthodontic consultation, it was determined that the maxillary teeth could not be considered for orthodontic treatment due to the existing periodontal status and bone levels. It should be noted that the option of orthodontic treatment and intrusion of the lower anterior teeth was presented to improve the jaw and overbite/overjet relationship of anterior teeth, but it was refused by the patient.

Considering the overall prognosis of the remaining maxillary teeth and esthetic desires of the patient to decrease the diastema width and idealize the overbite/overjet relationship of the anterior teeth, it was determined that none of the maxillary teeth could be retained. The impacted third molars were not removed because the risks of removal were greater than the risk of retaining them.

The optimal position of maxillary anterior and posterior teeth would be established utilizing the Kois Dento-Facial Analyzer system and the Panadent™ platform (Panadent, www.panadent.com) to construct an immediate transitional denture.²

After extraction of the maxillary teeth, socket grafts would be placed, and an immediate transitional denture would be inserted. This immediate denture would be assessed during the healing phase to plan the desired esthetics of the final hybrid prosthesis.

To correct the mandibular plane of occlusion, the mandibular incisal edges of the lower anterior teeth would be adjusted, and teeth Nos. 29 and 30 would be restored with core-supported all-ceramic restorations. The missing tooth No. 19 would be restored with an implant and a screw-retained porcelain-fused-to-metal (PFM) crown.

After healing, implants would be placed using the transitional denture as a guide to place the implants in restoratively driven positions. Following successful osseointegration, the implants would be uncovered and the final implant-supported fixed detachable prosthesis would be fabricated.

Treatment Phases Phase 1: Preventive Strategies

Periodontal maintenance and oral hygiene instructions were provided. The patient was placed on CariFree® (www.carifree.com) maintenance rinse to increase the pH of the oral environment, and a 3-month maintenance recare interval was established.

Phase 2: Planning and Transitional Immediate Denture

With the help of photographs and mounted models, the Panadent platform was used to first evaluate and then design the desired esthetically driven plane of occlusion.³ The maxillary teeth were extracted with the required bone grafting protocols. The immediate denture was inserted and relined, and occlusion was adjusted as needed during the healing phase.⁴ The esthetics of the immediate denture were evaluated, and all of the patient’s desires were considered before moving forward toward planning and fabricating the final prosthesis (Figure 10).

Phase 3: Restoring the Lower Arch

The mandibular anterior incisal edge position was adjusted to the desired plane of occlusion.⁵ All-ceramic cohesively retained restorations were planned for teeth Nos. 29 and 30 to manage the biomechanical risk and correct the plane of occlusion. An implant was placed to replace the missing tooth No. 19, and after the required healing time, a screw-retained PFM crown was inserted. Whitening trays were provided to the patient for the remaining lower teeth, and possible restorative options were reviewed if a satisfactory shade could not be achieved by bleaching alone.

Phase 4: Maxillary Arch Implant Surgery

After 4 months of healing, a CT-generated surgical guide was fabricated using the transitional denture to determine the ideal positions for implant placement. Six implants were placed in the positions of the cuspids, second premolars, and first molars with bilateral crestal-approach sinus elevations (Figure 11 and Figure 12). Cover screws were placed to eliminate the risk of overload during healing, and the transitional denture was adjusted and inserted.

Phase 5: Fabrication and Delivery of a Fixed, Detachable, Implant-Supported Final Restoration

After 16 weeks of healing, the implants were uncovered and their integration was confirmed using x-rays, reverse torque testing, and implant stability quotient (ISQ) readings (Figure 13). The transitional denture was duplicated and modified to be used as a custom tray for the final impression using open-tray impression copings (Figure 14).⁶ A facebow and bite registration were taken with this custom tray in place to communicate the desired tooth position and jaw relation to the laboratory.

A try-in of the titanium framework and a wax try-in were done to confirm passive fit of the framework and evaluate the esthetics. Jaw relation records in centric relation position were provided to the lab using an anterior jig fabricated lingual to the maxillary anterior teeth in wax.⁷

The hybrid was fabricated and inserted, access holes were filled, and the occlusion was equilibrated to achieve equal bilateral simultaneous contacts (Figure 15 through Figure 19).

Conclusion

Recognition and management of the risks that may cause failure of dental treatment and create disappointment for patients is a valuable tool, particularly in larger rehabilitation cases. This patient’s medical history, susceptibility to periodontal disease, increased functional risk, and occlusal dysfunction led to compromised function and debilitating esthetics. She had lost confidence in her smile and appearance. The treatment goals were to systematically manage the risks and improve the prognoses in each of the four dental categories with the ultimate goal being an improved quality of life. In the end, the patient’s esthetic desires were met, providing her the smile she longed for.

Acknowlegments

The author gratefully acknowledges John C. Kois, DMD, MSD, for his teaching, guidance, and patience; the Kois Center Editorial Board for its time and support; Ruth Bourke of RE Bourke Prosthodontic Art and Technology, Redmond, WA, for the fabrication of the beautiful hybrid prosthesis; and John Kawecki of the Princess Elizabeth Dental Laboratory, Edmonton, AB, Canada, for the lower posterior crowns.

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