Provisional Crown Fabrication Flashcards
7 cards from real EFDA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Provisional Crown Fabrication flashcards as text
When fabricating a provisional for a patient with known acrylic monomer sensitivity, the BEST alternative material is:
Answer: Bis-acryl composite resin
Bis-acryl composite resins contain less free monomer than PMMA and are preferred when patients have sensitivity to methacrylate monomers.
The purpose of applying petroleum jelly (Vaseline) to the tooth and adjacent tissues before injecting provisional material is to:
Answer: Act as a separating medium to prevent adhesion to tissues and teeth
Petroleum jelly acts as a separator so the provisional material does not adhere to the tooth structure or soft tissue during fabrication.
Which of the following is a sign of inadequate curing of a PMMA provisional crown?
Answer: Tacky or soft surface and persistent monomer odor
A tacky or soft surface with persistent monomer smell indicates incomplete polymerization, meaning the material has not fully cured.
A provisional crown is fractured at the isthmus connecting two pontics in a three-unit fixed partial denture. The MOST likely cause is:
Answer: Insufficient bulk of material at the connector area
The connector area must have adequate bulk to withstand occlusal forces; thin connectors are prone to fracture under stress.
When seating a provisional crown, the patient should be instructed to bite on a cotton roll to:
Answer: Help fully seat the crown and verify occlusal fit
Biting on a cotton roll applies even pressure to fully seat the crown and allows the clinician to assess if the occlusion is correct.
The color shade of a provisional crown is MOST important for which type of restoration?
Answer: Maxillary central incisor
Maxillary central incisors are highly visible, so shade matching of the provisional is critical to patient satisfaction and proper shade communication to the lab.
Which type of bur is BEST suited for adjusting internal fit of a bis-acryl provisional crown?
Answer: Round carbide bur at low speed
A round carbide bur at low speed allows precise removal of internal high spots without cracking the provisional material.