Partial dentures.
A partial denture is designed before it is made, and the design decisions are clinical. The Rx form offers cast and acrylic; which one, and how it is supported, determines whether it lasts.
Cast or acrylic
A cast metal framework is rigid, tooth-supported where rests are properly seated, thinner and more comfortable, and considerably more durable. It is the definitive option and it asks for a designed, prepared mouth.
An acrylic partial is tissue-borne, bulkier, and rests on the mucosa rather than transmitting load through the teeth. It is quicker and cheaper, and it suits transitional situations — during healing, while implant treatment proceeds, or where a definitive plan is not yet settled.
Where an acrylic partial is used long term, expect resorption beneath it, because it loads the ridge rather than the abutments.
Support is the design question
A partial denture is supported by teeth, by mucosa, or by both. Tooth support through properly seated rests transmits load along the long axes of the abutments, which the periodontium tolerates well. Tissue support loads the ridge, which resorbs.
The distinction matters most in free-end saddle cases, where there is no posterior abutment and the distal extension is inevitably tissue-borne. Those designs need careful rest placement, indirect retention and an accurate functional impression of the extension area.
Say which classification the case is, or describe the saddles. It is the starting point for every other design decision.
What the abutments need prepared
Rest seats cut into enamel or into restorations, so the rest sits within the tooth's contour rather than proud of it. Guide planes on the proximal surfaces to establish a path of insertion and improve stability. Adequate undercut for the clasp terminal, in the right place.
None of this can be added afterwards. A framework made for a mouth that has not been prepared will either not seat, will rock, or will rely on the clasp alone for support it was never designed to provide.
Where crowns are planned on abutment teeth, they must be made with the partial denture design in hand — rest seats, guide planes and survey line built into the crown.
Surveying and path of insertion
Every partial has one path of insertion, and the survey determines it. Which undercuts are usable, where clasps can engage, where guide planes go and where blockout is needed all follow from it.
The laboratory surveys the cast, but the clinical decisions — which teeth to clasp, how visible a clasp is acceptable, whether an abutment is sound enough to carry a rest — belong to the practice.
Send a design or describe your intent. A framework designed entirely at the bench from an unmarked cast is the laboratory guessing at your treatment plan.
Records
An accurate cast of the full arch, including the sulcus depth and the denture-bearing areas, not just the teeth. The opposing arch. An accurate jaw relation where the remaining occlusion does not define it unambiguously.
For free-end saddles, an altered cast or functional impression of the extension area is worth the additional stage — it records the tissue under load rather than at rest.
The Rx form has a Frame Try-in stage. Use it on anything complex: verifying the framework seats before teeth are set is considerably cheaper than discovering it afterwards.
What to put on the prescription
Tick Cast Partial or Acrylic Partial and the stage under Procedure. Mark the saddles and the abutments on the design chart, and describe the clasp and rest design you want.
Give the teeth shade and mould. Note any abutment you are concerned about, and say whether crowns are planned on any of them — the sequencing changes if so.
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Send a case
Digital scans and conventional impressions are both accepted. Cases move by UPS and Purolator, and Fairmont works with practices throughout British Columbia and across Canada.