1. The Full Mouth Reconstruction using Magnetic Attachments

Nakamura Y., Shoji K., Ando A. , Tanaka T.¹ , Okada M.¹ , Imaoka S., Ohno Y. and Tanaka Y.
Removable Prosthodontics, School of Dentistry, Aichi-Gakuin University
¹Department of Dental Laboratory , Aichi - Gakuin University Dental Hospital

Introduction

A magnetic attachment is a device using magnetic attractive force to provide and assist in the retention of dentures. Dentures using these special attachments have been well received by patients and treating dentists.　The purpose of this paper is the case presentation of a patient who presented with chief complaints of aesthetic dissatisfaction and inability to chew. This patient underwent full mouth reconstruction using magnetic attachments as retaining elements. The following is a summary of treatment completed.

Clinical History

The patient was a 42-year-old female with chief complaints of aesthetic dissatisfaction and masticatory dysfunction. The patient had received implants on the right lower molar region in 1995, but they were failed after 3 years. The edentulous upper and lower molar regions were left untreated for many years, resulting in a distorted plane of the occlusion and a decrease in occlusal vertical dimension. Although the patient visited several general practitioners and municipal hospitals to seek aesthetic correction, she was dissatisfied with the treatment results, and then consulted with our department.

Initial Status

The patient had Kennedy Class II relationship in the upper and lower arches. There was severe molar occlusal destruction with a occlusal plane discrepancy. Also present were areas of root fracture, failing restorations with ill-fitting margins, and poor periodontal tissue health. There was severe redness and swelling of periodontal tissues around the right upper lateral incisor, and right lower first premolar areas. Radiographic examination demonstrated endodontic problems of apical radiolucencies and poor endodontic fills in other areas. Clinical examination revealed the bone torus which can be an obstacle to the restorative treatment (Fig. 1).

Treatment Procedure

1 . Exploration

Fig . 2 Face-bow transfar and Wax up for treatment

The mounted study casts were made and mounted on an articulator using face-bow transfer procedure. The diagnostic wax-up was performed to show an anticapated result and establish a restorative treatment plan showing space and dental relationship problems that might exist. The diagnostic modeling provides excellent material for patient education and demonstration (Fig. 2).

Initial caries control and treatment of endodontic etiology., Extractions if necessary.

2 . Temporary Restoration and Initial Treatment Denture

The quality of the existing restorations caused a poor occlusal and periodontal environment. These were removed. Temporary restorations were placed to secure the temporary masticatory function, pronunciation, and to evaluate ane initial esthetic result, and to provide for initial periodontal and occlusal treatments stability. Temporary restorations were fabricated based on the diagnostic wax-up. In the edentulous area, treatment denture was placed to improve the occlusal support (Fig. 3).

3 . Provisional Restoration

After the completion of the initial periodontal treatment, resin cores with fiber posts were placed in the remaining teeth to avoid dental fracture. A provisional restoration with improved esthetics and occlusal height, and adjusted occlusal vertical dimension from the temporary restoration was fabricated (Fig. 4).

4. Surgical Treatment

Maxillary bony exostosis that may interfere with final denture fabrication was surgically resected (Fig. 5).

5. Preparation

Fig . 6 Preparation for Abutment Tooth

To protect vital abutment teeth, preparation was performed in 3 steps with the time interval to promote the formation of the secondary dentin that protects the pulp.(Fig. 6)

6. Final Provisional Restoration

A final provisional restoration with improved occlusion, periodontal environment and esthetics was fabricated and presented for approval by the patient. .

7. Design of Final Restoration

Table . 1 Upper Design

Maxillary denture design includes an extracoronal magnetic attachment on the distal surface of the left upper canine, slit on the distal surface of the right upper canine, and metal crowns on the right upper second premolar and first molar (Table 1).

Mandibular denture design includes an extracoronal magnetic attachment on the distal surface of the canines, and metal crowns on the left first and second molars (Table 2).

8. Maxillo-mandibular Relationships and Articulator Mounting.

Cross mount transfer technique was used to preserve the original maxillo-mandibular cast relations and mounting. This procedure also preserves original diagnostic occlusal design and vertical dimension of the provisional restoration to the final restoration (Fig. 7). Since provisional and work models are transferred on the same axis, these models can also be compared during fabrication of the final restoration to use as a reference to the opposing arch and teeth. This method simplifies the

fabrication procedures such as wax-up.

9. Trial Fitting Procedures

Trial fitting of the metal work and metal crowns was performed. Transfer impression was taken following the conventional methods after try fitting, followed by the fabrication and try fitting of the wax denture.

10. Final Restoration

Fig. 8 shows upper and Fig. 9 shows lower final restorations.

Fig . 8 Upper Final Restoration

Fig . 9 Lower Final Restoration

Discussion

The patient was satisfied with the esthetic results of the final restoration with magnetic attachments. The retention obtained with the attachments achieved highly satisfactory functional results. The patient was satisfied with the prosthetic retentive force (Fig. 10).

The postoperative course has been uneventful. However, the design of a final restoration is complex as the ideal combination of esthetics and functionality is difficult to obtain. It is important that regular maintenance is obtained. (Fig. 11).

References

1. Gillings, B. R. D.: Magnetic retention for complete and partial overdentures, Part. J. Prosthet. Dent., 45(5): 484-491, 1981.

2. Jackson,T.R.: The application of rare earth magnetic retention toosseointegrated implants. Int. J. Oral & Maxill. Imp., 1:81-92, 1986.

3. Tanaka, Y.: Dental Magnetic Attachment, Q & A, Ishiyaku Publishers, Inc. (Tokyo),

1995.

4. Mizutani, H., Ishihata, N. and Nakamura, K.: Removable partial denture used the magnetic attachment, Quintessence Publishing Co., Ltd. (Tokyo), 1994.