J Korean Acad Prosthodont.  2015 Jan;53(1):66-73. 10.4047/jkap.2015.53.1.66.

The implant overdenture on the edentulous mandible using CAD/CAM system: A case report

• Lee SE
• Lee SH
• Jeon YC
• Jeong CM
• Yun MJ
• Huh JB

• KMID: 2057209
• DOI: http://doi.org/10.4047/jkap.2015.53.1.66

Abstract

Alveolar bone loss and deformation can be a risk factor in removable prosthetic restoration treatment for partially or fully edentulous patients. The use of implants to solve this problem could improve the support, retention and stability of removable restoration. Attachments used in implant overdenture are versatile. The attachment should be selected according to the patients' conditions. Milled bar has been chosen when readymade bar could not be used because of the narrow distance between implants or firm stability and support of supra-structure were needed. Milled bar design is able to provide cross arch stabilization and comfortability to patients. However, it needs skilled laboratory procedures. Recently, the fabrication of milled bar has become simple and its suitability has been improved through the development of CAD/CAM system. In a 67-year-old female Alzheimer's disease patient with 8 implant fixtures on the fully edentulous site of mandible, implant overdenture with using milled bar and magnet attachment was planned. As rapid treatment was required, CAD/CAM system was used to make a simple laboratory procedure instead of a traditional fabrication process. With this system, implant overdenture with milled bar can be fabricated esthetically and functionally.

Keyword

CAD/CAM; Implant overdenture; Attachment; Cobalt-Chromium Alloys

MeSH Terms

Aged
Alveolar Bone Loss
Alzheimer Disease
Chromium Alloys
Denture, Overlay*
Female
Humans
Mandible*
Risk Factors
Chromium Alloys

Figure

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  Fig. 1. Intraoral view of the patient's preoperative condition. (A, E) Occlusal view of maxilla and mandible, (B, D) Lateral view, (C) Frontal view.

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  Fig. 2. Final impression taking of maxilla and mandible (B, E) with individual trays (A, D) and Definitive cast fabrication of maxilla and mandible (C, F).

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  Fig. 3. Laboratory procedures using 3Shape software. (A) Scanned customized abutments (Gray), gingiva (Pink) and bite material of antagonistic teeth (Purple), (B) Confirmation of fixture and hole direction, (C) Mandibular teeth arrangement according to the maxillary temporary denture, (D) Establishment of bar margin, (E) Design a milled bar and decision the position of magnet attachments, (F) Evaluation of the bar position according to the arranged and antagonistic teeth.

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  Fig. 4. Fabricated milled bar (A) and verification of bar position in the oral cavity (B, C).

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  Fig. 5. Decision of vertical dimension using Wilis method (A, B), Facebow transfer (C) and mounted master casts according to the jaw relation record (D).

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  Fig. 6. Framework design. covering milled bar (A), giving the autopolymerizing acrylic resin space under the framework (pink) (B), and confirmation of magnet position on the framework using CAD/CAM system (C).

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  Fig. 7. Esthetic try-in with wax denture. (A, C) Occlusal view of maxilla and mandible, (B) Frontal view.

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  Fig. 8. Final restoration was placed in patient's oral cavity. (A, E) Occlusal view of maxilla and mandible, (B, D) Lateral view, (C) Frontal view.

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