J Dent Rehabil Appl Sci.  2021 Mar;37(1):39-47. 10.14368/jdras.2021.37.1.39.

Cr-Co removable partial denture treatment fabricated by selective laser melting: a case report

• Yim JH
• Shin SY

• KMID: 2525977
• DOI: http://doi.org/10.14368/jdras.2021.37.1.39

Abstract

Compared to conventional method, if metal framework of removable partial denture is fabricated by selective laser melting, various laboratory works are omitted, saving time and simplifying the process. In addition, metal framework with homogeneous density can be obtained, expecting excellent mechanical properties, especially resistance to fatigue fracture. In these cases, impression were taken using conventional methods in partial edentulous patients, master casts were fabricated and scanned to obtain digital data. After designing the metal frameworks on the scanned data, removable partial dentures were fabricated using selective laser melting methods. Through these procedure, satisfactory outcomes were achieved both in functional and esthetic aspects.

Keyword

selective laser melting (SLM); 3D printing; removable partial denture

Figure

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  Fig. 1 Panoramic view of patient in case 1.

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  Fig. 2 Fracture of major connector in case 1. (A) Fractured position in major connector, (B) Fractured facet of major connector. Note the porous surface at the facet.

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  Fig. 3 Surveying procedure to identify proper path of insertion using dental surveyor in case 1. Prior to digital surveying, checking the path of the surveyed crowns. (A) Surveying of premolars, (B) Surveying of canines for checking path of insertion.

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  Fig. 4 Definitive impression in case 1. (A) Impression was taken by polyvinyl siloxane. (B) Impression was poured with improved dental stone.

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  Fig. 5 3D scan and design of metal framework in case 1. (A) Scanned master cast with determined path of insertion, (B) Designing retention grid and major connector, (C) Designing minor connector and clasp assemblies, (D) Pre-manufacturing of framework.

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  Fig. 6 Cut-off facet of metal framework fabricated by SLM in case 1. Note the dense surface at the facet showing more density than fractured porous surface.

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  Fig. 7 Restoration of final denture in case 1. Showing proper adaptation of framework and comfort for patients.

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  Fig. 8 Panoramic view of patient in case 2.

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  Fig. 9 Fractured facet of I-bar in case 2. The I-bar is entirely cut off from removable partial denture resulting from improper soft tissue undercut.

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  Fig. 10 Surveying procedure to identify proper path of insertion and undercut of soft tissue using dental surveyor in case 2. Prior to digital surveying, checking the path of the surveyed crowns.

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  Fig. 11 3D scan and design of metal framework in case 2. (A) Scanned master cast with determined path of insertion, (B) Designing retention grid and major connector, (C) Designing minor connector and clasp assemblies, (D) Pre-manufacturing of framework.

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  Fig. 12 Restoration of final denture in case 2. The patient showed satisfaction with new removable partial denture.

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  Fig. 13 Fractured metal framework in case 3. (A) Fracture at retentive arm in maxillary removable partial denture (#26), (B) Fracutre at minor connector and rest in mandibular removable partial denture (#46).

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  Fig. 14 Surveying procedure to identify proper path of insertion and undercut of pre-existed surveyed crowns and natural teeth in case 3. (A) Surveying of maxilla, (B) Sureveying of mandible.

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  Fig. 15 Definitive impression in case 3. Impression was taken by polyvinyl siloxane. (A) Impression of maxilla, (B) Impression of mandible.

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  Fig. 16 3D scan and design of metal framework in case 3. (A) Scanned master cast with determined path of insertion, (B) Designing retention grid and major connector, (C) Designing minor connector and clasp assemblies, (D) Pre-manufacturing of framework.

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  Fig. 17 Restoration of final denture in case 3. (A) Maxilla, (B) Mandible. Kennedy class III case in maxillary restoration and short tissue supported area in mandibular restoration resulted in great stability and patient’s satisfaction.

Reference

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