Complete Rehabilitation of a Generalized Chronic Tooth Sensitivity and Rampant Caries of a Clinical Situation Using Implant Supported Fixed Zirconia Prostheses

 

Tony Daher, DDS, MSEd, FACP, FICD – tonydaher@verizon.net
Board Certified in Prosthodontics and Implant Dentistry. Co-Director, Global Dental Implant Academy

Dental News Magazine – June 2018 Issue

 

Background and Purpose

Complete-arch implant-supported restorations are widely accepted as a treatment option for completely edentulous patients and have been documented to have a success rate greater than 90%1. Many combinations of materials have been used for these types of restorations such as metal alloy-acrylic, metal alloy-composite, and metal alloy-ceramic. 

However, prosthesis-related complications with acrylic resin and porcelain-veneered metal frameworks are commonly reported over short and long-term periods: fracture of the acrylic resin veneer, prosthetic screw loosening/fracture, wear and fracture of resin denture teeth, fracture of prosthesis framework, and poor gingival esthetics and architecture.²

Therefore, dentists started to look for other material options. The evolution of computer-aided design and computer-aided manufacturing (CAD/CAM) systems has allowed the introduction of an alternative restorative approach to the complete-arch implant prosthesis such as Monolithic Zirconia prosthesis. 

Over the past decade, Zirconia technology has had a significant impact on dentistry because of its biocompatibility, esthetics, and material strength.³ 

The monolithic nature results in no dissimilar interfaces, and thus minimizes fracture and/or chipping events, creates a greater bulk of material to improve the structural properties of the individual prosthesis, and enables efficient fabrication and care delivery through CAD/CAM manufacturing.⁴

Considering the increased use of Monolithic Zirconia in complete-mouth rehabilitations. The following case presents the clinical and laboratory protocol to fabricate a zirconia full arch prosthesis.

The fabrication of a full-arch implant supported zirconia prosthesis is technique sensitive and should follow the appropriate clinical steps discussed in this case study. The clinician should do a careful patient selection and a thorough planning (location and number of implants, framework design, appropriate occlusal scheme) for a successful and predictable outcome.

Clinical Data and diagnosis

A 41-year-old female patient was referred by her general dentist to our prosthodontic practice for a comprehensive treatment plan. Her chief complaints were “I have very sensitive teeth; and have mouth odor.” “My mouth always feels dry; and my dentist told me I have a lot of cavities.”

Her desires for treatment are: “I want to fix my mouth and replace the missing teeth, so I can eat and be comfortable and to look good.” The patient has been receiving sporadic dental treatments during the past 10 years. She stated that the teeth were lost due to extensive decay and gum problems resulting in abscesses requiring extractions. 

Medical history: The patient is medically compromised. She had multiple surgery: Neck and back surgery from an accident at work, and she was disabled for a long period of time. She also had gastric bypass and was not adequately done so she was constantly vomiting. This made all her teeth eroded and became very sensitive.

Clinical Findings/Problem list: 

•  Temporo-mandibular dysfunction

•   Partially edentulous maxilla and mandible.

• Multiple defective existing restorations with
recurrent decays.

•  Generalized tooth erosion and rampant cervical tooth decay.

•   Angular cheilitis.

• Inadequate and poor oral hygiene with
moderate plaque and calculus.

•  Traumatic occlusion with inadequate occlusal vertical dimension and plane of occlusion.

Clinical Decision Making and Treatment Plan

After gathering all the clinical data from clinical extraoral and intraoral examination, articulated diagnostic casts using an earbow and Gothic arch tracings, and radiographs; we have presented to the patient in writing the following treatment plan in the following letter:

“This letter will confirm the major elements of our conversation during your last appointment when we discussed the care we plan to provide for you.  Because you wanted a more predictable with a long outcome treatment and you have some
financial constraints, the following treatments were discussed with you.

1.  As you know, your advanced oral condition and the excessive severe tooth sensitivity and rampant decay mandate the removal of any questionable teeth with poor outcome to restore in a predictable manner your mouth. 

2.  I have presented to you with many options after tooth extraction and we have discussed the benefits of each option. You have agreed on the following option:

8 implants and fixed bridges supported by implants and this in the upper and lower jaws.       

Treatment Sequence:

1.  Before the removal of all compromised teeth, upper and lower interim immediate prostheses to be fabricated and placed immediately after tooth removal. The reason of making these prostheses before the removal of your teeth is that for better healing and esthetic reasons. (Figures 3, 4)

2.  The placement of implants will depend upon the position of the final denture teeth for the achievement of optimum esthetic and function. Therefore, a CBCT radiographs is made with a radiographic template for a 3D bone evaluation.

3.  Then 16 Zimmer TSV® implants are placed by our Oral and Maxillofacial surgeon in a hospital setting. 

4.  After implant integration and the healing is complete, the final fixed prostheses are fabricated. To get a predictable result with the final restorations, it is important to fabricate provisional bridges that will be used for some time. These provisional bridges will be adjusted till the achievement of an acceptable esthetic and functional result. These will be the blue print of the final fixed prostheses.

5.  Continuous care visits.

This treatment we plan should have good outcome and permit to achieve good function and a pleasing smile. 

We anticipate that this work might be completed in 18 months. The time factor will depend greatly upon arriving at a comfortable and esthetic result with your dental restorations.”

Conclusion

This treatment has achieved good function and a pleasing smile. With a such of a complex comprehensive treatment plan, it is important to state to the patient the following:

“Everyone has some limitations, which impact on the result.  Some consideration must be given to the fact that the success rate of maxillary implants is between 90% to 95%, there are sometimes adverse reactions and surgical or restorative corrections may be required.  Naturally, with the human body it is impossible to make guarantees.  Nonetheless, we (the dental office) will be responsible for any work we have treated for a period of 12 months, and make any indicated modifications or adjustments for these teeth without charge.  Experience has shown that this is adequate time for any latent problems to manifest. 

It will be important for you to keep recall appointments following our care to ensure that your mouth is maintained in a healthy manner.  Excellent oral hygiene is essential and these recall appointments are not included in the initial fee.”

In the end, it is worthy to state that complete-arch implant-supported monolithic zirconia fixed dental prostheses may be considered in these scenarios, but long-term clinical performance is still to be assessed.

 

Bibliography

1. Rohlin M, Nilner K, Davidson T, Gynther G, Hultin M, Jemt T, et al. Treatment of adult patients with edentulous arches: a systematic review. Int J Prosthodont 2012;25:553-67.

2. Bozini T, Petridis H, Garefis K, Garefis P. A meta-analysis of prosthodontic complication rates of implant-supported fixed dental prostheses in edentu- lous patients after an observation period of at least 5 years. Int J Oral Max- illofac Implants 2011;26:304-18.

3. Vagkopoulou T, Koutayas SO, Koidis P, Strub JR. Zirconia in dentistry: part 1. Discovering the nature of an upcoming bio- ceramic. Eur J Esthet Dent 2009;4:130-51.

4. Le M, Papia E, Larsson C. The clinical success of tooth- and implant- supported zirconia-based fixed dental prostheses. A systematic review. J Oral Rehabil 2015;42:467-80.

5. Abdulmajeed, A.A., Lim, K.G., Närhi, T.O., Cooper, L.F., 2016. Complete-arch implant-supported monolithic zirconia fixed dental prostheses: A systematic review. J Prosthet Dent 115, 672–677.e1. doi:10.1016/j.prosdent.2015.08.025