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Hi everyone, how you doing?. Hopefully like everyone is having a great moments and memories. Without much ado, would like to share something important without you, it is much of an art of work of dentistry.

It is about using a dental material known as shellac to fabricate a special tray from a preliminary cast.

First of, what is a cast ?

A cast with reference to impression in dentistry is a positive copy of an impression took using an impression materials such as alginate, greenstick compound, impression compound and so on with an impression tray in order to take a positive copy or imprints from the mouth of a partially edentulous or an edentulous patient.

Now let's go to the major topic of the post.

1- Introduction

As usual introduction to the examiner in a humble manner before proceeding to the next step of the procedure.

Taking the instance below as an example;

Good afternoon sir/ma, my name is Dr WXYZ and I want to demonstrate how to use shellac to fabricate a special tray( specific individual tray) from preliminary cast.

2- Naming fully the required Armamentarium for the procedure

First, I will need the following materials and instruments: shellac base plate, wax, wax knife or carver, sharp pencil, bunsen burner, sand paper(abrasive), and the upper and lower primary cast(preliminary cast) mould.

3- Stating the required procedures in steps following an appropriate order

A scenario could be reported as saying it like the example given below:
E.g
After making the primary cast from the primary impression using alginate, I will use pencil to mark and tick the borders of the tray on the primary cast and mark out legible demarcations.

The borders of the tray should be about 2mm short of the functional depth of the buccal and labial vestibular sulcus. The tray should also extend up to the posterior palatal seal area, and the retromolar pad.

Next is to adapt wax firmly on the upper and lower primary cast. The wax is to serve as a spacer.

Then I will pass the shellac base plate over the bunsen flame to molten it and quickly adapt it on the cast before it hardens. I will do this till the shellac has fully engulfed the cast.

Using the pencil mark as a tracing and guide, I will use my wax knife to remove shellac material that is in excess, while also making relief areas for all the frenal attachments available in the oral cavity.

After the trimmings and the reliefs, I will use the remaining shellac material to make handles and attach them to the upper and lower trays.

Finally, I will use sandpaper(abrasives) to smoothen the rough areas on the shellac special tray and on the trimmed edges.

That's all as regards the fabrication of Special (Individual) tray using Shellac Base Plate material

Stay Blessed and Happy Blurting 🎉
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