Full mouth prosthetic case applying magnetic attachments
in various shapes
R. Kanbara, Y. Nakamura, K. Shoji, K. Yoshihara, H. Konno, Y. Takada 1, Yu. Ohno, Y. Tanaka
Department of Removable Prosthodontics, School of Dentistry, Aichi-Gakuin University
1

Division of Biomaterials, Tohoku University Graduate School of Dentistry

Introduction
The patient was a 83-year-old female who lost her bilateral molar occlusion due to thebilateral upper free-end and multiple tooth loss. A X-ray image showed alveolar bone resorption
due to advanced periodontal disease, malalignment, and the collapse of the occlusal plane.
Stress-bearing ability and preservability of the upper and lower remaining teeth were examined,followed by a thorough consultation with a patient regarding the esthetic recovery based on the
diagnostic wax-up. Provisional restoration was placed in the upper jaw to correct the occlusal
plane and tooth alignment. The crowns of the lower remaining teeth were truncated, and treatment
overdenture was placed. The patient was followed for several months, and final restoration wasplaced after confirming that there are no functional and esthetic problems. For the design of thefinal restoration, radicular attachments using magnetic attachment and MT crowns were chosen in
the lower jaw, and porcelain-fused-to-metal crown and extracoronal magnetic attachment werechosen in the upper jaw.
The patient is satisfied with functional and esthetic results. Postoperative prognosis at 3years and a half after the placement of new dentures is satisfactory.

Initial Situation
Fig. 1 shows the intraoral image at first visit. The patient was not using the lower denture
due to poor fitting of a denture. Bilateral occlusal support was lost, and malalignment of anterior
teeth due to advanced periodontal disease and the collapse of the occlusal plane were observed.

Fig. 1 the intraoral image at first visit

Fig. 2 shows a panoramic X-ray at first visit. Problems were extracted from the oral
examination and X-ray image. Problems included mandibular alveolar bone resorption, thecollapse of the upper and lower occlusal plane, poor prosthesis, poor root canal filling andremaining teeth.

Fig. 2 a panoramic X-ray at first visit

Treatment Procedure
1． Exploration1）Mandibular
Fig. 3 shows a dental X-ray of the lower remaining teeth. Severe alveolar resorption in
the anterior area, poor prosthesis in the right molar area, and the remaining teeth in the left molararea were observed in the mandible (Fig. 3). Treatment plans in the mandible were root canaltreatment in the remaining teeth, followed by an overdenture for all the remaining teeth to improvethe crown-root ratio.
2）Maxilla
Fig. 4 shows the frontal and occlusal views of the maxillary arch. The dental axis collapse
and space were observed in the arch, and disharmony of the dental arch was observed in theocclusal view (Fig. 4). Treatment plans in the maxilla were prosthetic restoration of the remaining
teeth for esthetic and functional recovery, and denture in the bilateral missing molar areas.
3）WAX-UP for exploration
A study model was mounted on an articulator using a face bow transfer (Fig. 5). For themaxillary dental arch, ideal dental arch and shape were fabricated using dental wax to use as a
guide of final restoration for esthetic recovery. For the mandibular dental arch, prosthetic
restoration of the lower right first and second molars and overdenture were simulated. Lower teeth
were aligned to harmonize with upper teeth. The diagnostic wax-up is performed to examine if thepresent occlusal height is proper for the prosthetic treatment, and is used as an explanatory
material.

Fig. 3 a dental X-ray of the lower remaining teeth

Fig. 4 the frontal and occlusal views of the maxillary arch

Fig. 5 WAX-UP for exploration
2． The Designs of Final Restoration
The designs of upper and lower restorations were determined based on the oral
examination, X-ray image, and diagnostic wax-up. The designs of the mandibular restorations
included radicular-type magnetic attachments in the lower anterior area between the right lateralincisor and the left canine, and attachment denture using MT crowns in the well-preserved lower
right second molar (Fig. 6).
The upper prosthesis was also designed based on the oral examination, X-ray image,and diagnostic wax-up. The condition of the upper remaining teeth was fair without mobility. An
extracoronal magnetic attachment was placed on the bilateral upper second premolars, andesthetic attachment denture without a clasp was placed on the bilateral molars. Three abutment
teeth up to the canine were joined using porcelain-fused-to-metal crown (Fig. 7).

Fig. 6 the designs of lower restorations

Fig. 7 the designs of upper restorations

3． Treatment Process （maxilla）
1）Temporary restoration
A temporary crown was placed to secure masticatory function, pronunciation, andesthetics (Fig. 8), and to facilitate initial periodontal and root canal treatment.

Fig. 8 temporary restoration wearing

2）Change of the designs of maxilla prosthetic appliance
Root fracture of the upper left second premolar was confirmed during root canaltreatment during initial treatment using temporary crown. Although the patient was followed for acertain period of time, the tooth extraction was indicated due to the lingering symptoms such as
spontaneous pain. The maxillary restoration design was threofore altered to place an extracoronalmagnetic attachment on the left first premolar instead of the second premolar. The canine and thefirst premolar were joined considering the condition of the periodontal tissue (Fig. 9).

Fig. 9 change of the designs of maxilla prosthetic appliance3）Provisional restoration
A provisional restoration esthetically and functionally improved from a temporary crown
was fabricated based on the diagnostic wax-up after the initial periodontal and root canaltreatments, and placed.
4． Treatment Process （mandibular）
1）Root canal treatment and Keeper caps and MT-crown inner crown wearing
Fig. 10 shows an intraoral image and panoramic X-ray at the completion of the root canaltreatment. A keeper caps and MT inner crown were placed according to the treatment plan andprosthetic design (Fig. 11).

Fig. 10 an intraoral image and panoramic X-ray at the completion of the root canal treatment

Fig. 11 a keeper caps and MT inner crown wearing
5． Final Provisional Restoration and Treatment Denture wearing
Fig. 12 shows an intraoral image with upper final provisional restoration and upper andlower treatment dentures. Final provisional restoration was fabricated by making functional andmorphological alterations of the previous provisional restoration. The occlusal plane, upper dental
arch, and incisal overjet were improved compared with the initial visit (Fig. 12). The patient wasfollowed for several months with the final provisional restoration. Since there was no problem in
occlusal height and temporomandibular joint, final restoration was placed.

Fig. 12an intraoral image with upper final provisional restoration
and upper and lower treatment dentures6．The Procedure of Final Restoration

1）Bite taking
Fig. 13 shows the bite taking of the final restoration. Bite taking was performed using abite plate based on the occlusal height of the treatment denture. Occlusal height with upperprovisional restoration was taken, followed by bite taking with the upper abutment teeth. For thebite taking between the abutment teeth and the bite plate, occlusal height between the obtained
provisional restoration and bite plate was secured by an upper treatment denture, followed by theremoval of provisional restorations in anterior teeth area and bite taking (Fig. 14). The upper
denture was removed, and bite taking of the molar abutment teeth was performed using the same
silicone bite (Fig. 15).
Since the bite plate was used for bite taking, obtained horizontal maxillomandibular
relationship should be confirmed. Horizontal occlusal relationship was registered using Gothicarch to obtain horizontal jaw position according to the conventional method (Fig. 16).

Fig. 13

Fig. 14the bite taking of the final restoration

removing of provisional restorations in anterior teeth area and bite taking

Fig. 15

removing the upper denture and bite taking of the molar abutment teeth

Fig. 16

using Gothic arch to obtain horizontal jaw2）Try fitting
Fig. 17 shows the final restorations including upper and lower wax denture, upper
porcelain-fused-to-metal crown, extracoronal magnetic attachment, and lower MT outer crown.
These final restorations were tried in to verify occlusion and esthetics.

3）Final restoration
Fig. 18 shows upper and lower final dentures. The image on the left shows the occlusal
view, and the right shows the mucosal surface of a denture base. The metal used for the metalbase was gold platinum alloy.

Fig. 17

try fitting of the final restorations

including upper and lower wax denture

Fig. 18

upper and lower final dentures

Discussions
Fig. 19 shows intraoral image of the patient with final restorations. The accurate intraoral
position of a denture was determined by magnetic attachments. Magnetic attachments allowedeasy placement and removal of a denture, and esthetics and function were markedly improved.
The patient was satisfied with the results (Fig. 19).
Fig. 20 shows an intraoral image at 3 years after the placement of final restorations.
Although mild redness in the gum around keeper caps and palatal indentation due to a denture
were observed, the patient did not complain of pain, and there was no problem in masticatory
function and esthetic appearance.
Fig. 21 shows the intraoral dental X-ray image of the first visit and present. Although thelower left second molar was hemisected, there was no clinical symptom in abutment teeth, and theprognosis was satisfactory. The results suggest the mechanical usefulness of magnetic
attachments on abutment teeth. Although the designs of upper right second premolar and left firstpremolar with extracoronal magnetic attachments included cantilever structure, no alveolar
resorption related to this design was observed. It is suggested that stress was distributed by theconcomitant use of bracing arms and interlocks.
The results of the present study confirmed the effectiveness of magnetic attachments
which can be applied in various shapes such as extracoronal attachment, MT crown, and root cap
attachment depending on the clinical situations.
Regular follow-up and oral care by specialists will be continued for a favorable prognosis.

Fig. 19

intraoral image of the patient with final restorations

Fig. 20an intraoral image at 3 years after the placement of final restorations

Fig. 21the intraoral dental X-ray image of the first visit and presentReferences
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