J Dent Rehabil Appl Sci.  2016 Sep;32(3):246-254. 10.14368/jdras.2016.32.3.246.

Fixed prostheses fabricated by direct metal laser sintering system: case report

• Baek JW
• Shin SY

• KMID: 2357854
• DOI: http://doi.org/10.14368/jdras.2016.32.3.246

Abstract

Nowadays, 3 dimentional (3D) printing, especially Direct Metal Laser Sintering (DMLS) system is used in dentistry. DMLS system has recently been introduced for fabrication metal framework for metal ceramic crowns to overcome the disadvantages of the casting method and computer aided design/computer aided manufacturing (CAD/CAM) milling system. DMLS system uses a high-temperature laser beam to selectively heat a substructure metal powder based on the CAD data with the framework design. A thin layer of the beamed area becomes fused, and the metal framework is completed by laminating these thin layers. Utilizing DMLS system to fabricate fixed prostheses is expected to achieve free-from shaping without mold and limitations from cutting tools, fabricate prostheses with complex geometry, prevent distortion and fabrication defects that inherent to conventional fabrication methods. The purpose of this case report is to demonstrate various fixed prostheses such as long span fixed prostheses, post to achieve satisfactory results in functional and esthetic aspects.

Keyword

3D Printing; direct metal laser sintering system; fixed prostheses; post

MeSH Terms

Ceramics
Crowns
Dentistry
Fungi
Hot Temperature
Methods
Printing, Three-Dimensional
Prostheses and Implants*

Figure

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  Fig. 1 Preoperative views of 6-unit fixed prosthesis at the time of initial examination. Labial view (the part shown in dotted line) and lateral views showed porcelain fracture of maxillary left central incisor. (A) Maxillary occlusal view, (B) Right lateral view, (C) Frontal view, (D) Left lateral view, (E) Mandibular occlusal view.

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  Fig. 2 Final impression taking. (A) After removal of old prosthesis, teeth were intact. Preparation process was the same method as conventional process. After preparation process, cord packing was done for final impression, (B) Final impression was presented, (C) Master cast was fabricated for scanning by Dental wings®(Dental Wings Inc.).

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  Fig. 3 Metal coping fabrication. (A) After scanning master cast, metal coping was designed by Dental wings DWOS 5.0 software®(Dental Wings Inc.) 3-dimensionally, (B) After metal coping was fabricated by DMLS system, metal copingwas tried in master cast before try in mouth, (C) Intraoral frontal view showed after metal coping try-in. Metal coping showed superior marginal and internal fit without distortion and fabrication defects.

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  Fig. 4 Intraoral frontal view at maximum intercuspal position after prosthodontic treatment. Final restoration was presented natural-looking emergence profile, stable alveolar ridge, and harmonious color.

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  Fig. 5 Preoperative views at the time of initial examination. Occlusal view(the part shown in dotted line) showed missing tooth of maxillary right second premolar. (A) Maxillary occlusal view, (B) Right lateral view, (C) Frontal view, (D) Left lateral view, (E) Mandibular occlusal view.

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  Fig. 6 Final impression taking. (A) After old prosthesis of maxillary right molars was removed, maxillary right first premolar was prepared additionally for 4-unit fixed prosthesis. After preparation process, cord packing was done, (B) Final impression was taken. (C) Master cast was fabricated by pouring final impression as the same method as conventional process.

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  Fig. 7 Metal coping fabrication. (A) After master cast scanning by Dental wings®(Dental Wings Inc.), metal coping was designed 3-dimensionally, (B) Intraoral occlusal view showed after metal coping try-in. Metal coping showed superior marginal and internal fit.

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  Fig. 8 Intraoral occlusal and frontal view after prosthodontic treatment. Final restoration achieved satisfactory results in functional and esthetic aspects.

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  Fig. 9 Intraoral occlusal and frontal views showed insufficient remained tooth of Maxillary left incisors for abutment teeth of 5-unit fixed prosthesis.

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  Fig. 10 Final impression was taken and scanned directly by Dental wings®. In this case, master cast was not fabricated.

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  Fig. 11 Metal post. (A) Metal coping was designed by Dental wings DWOS 5.0 software®(Dental Wings Inc.), (B) Metal coping was fabricated by DMLS system, (C) Intraoral frontal view showed that metal coping presented superior marginal fit without distortion.

Reference

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