Question

There is the conventional dental crown making process. However, recently, new crown-making methods have been originated. Explain and compare the various crown making processes.

Answer 1

Lost wax technique is old school technique which has been in used since past for making of dental crown.. But with various advances in dental fields some techniques has evolved like less time cosuming,more accuracy,less man power etc.

Various crown making processes:

1) CAD CAM (computer aided design- computer aided manufacturing)

CAD CAM system mainly includes 3 process which are scanning, designing and milling. Scanning process does conversion of shape of prepared teeth into 3D form. Then with help of specific software it gets converted into 3D map. Then operater can design shape of crown as per need with using various tools in same software, Then signal send to milling machine which create desired shape from restorative material like presintered alumina or zirconia.advantages are simplicity,rapid fabrication,no specific impression technique required for process. Disdvantages includes high cost of machine and mastering technique for operating machine.

2) DMLS (Direct metal laser sintering)

this is 3D printing technique which uses laser and directly create metal part from its 3D computer model. Working material use is finely powedered metal. crown build up with this method allows in layer by layer deposition. This allows efficient and affordable production of all complex structure of a prepared crown. but not possible with substractive or formative methods. Advantages includes Direct metal printing, Variety of materials like nickel chromium alloys, ceramic, glod can be used,recyclable materials. But some disadvantages are very high pricing,porous crown parts can be formed and small parts can be efficiently formed than large structure.

3) Impression free technique: (The cerec 2 camera: optical impression)

In this technique,digital camera placed inside oral cavity on prepared tooth and optical impression has been recored with all plane and then further process is like in CAD CAM.