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Biomimetic Dentistry Glossary

Peripheral Rim Fracture (PRF)

A key term of biomimetic restorative dentistry, clearly defined. Part of The Hybrid Layer's free reference glossary.

Glossary term Free to read

Summary – What is a Peripheral Rim Fracture (PRF)?

If a traditional cavity is prepared with an isthmus width >2 mm, the tooth is no longer connected in a biomimetic way. The tooth can flex in a range of around 200 microns which results in stress concentration. Fracture resistance decreases and the marginal ridges are more likely to crack, leading to Peripheral Rim Fractures (PRF).

Photo showing a PRF (Peripheral Rim Fracture)
Fig 1. Clinical example of a Peripheral Rim Fracture (PRF).
Photo credit: Dr Pete Butkus

Learn More…

To learn more about Peripheral Rim Fractures in relation to structural compromises and micromovements, see Lesson 2 of the Six Lessons Approach to Biomimetic Dentistry below.

Lesson 2 – Diagnosis And Treatment Of Structural Compromises
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See the PRF in practice

Three lectures on the fractures behind structural compromise: biomimetic cracked-teeth diagnosis and treatment, crack dynamics in dental hard tissues, and crack treatment options and prevalence.

Cracked Teeth: Biomimetic Analysis, Diagnosis and Treatment — Dr Andras Forster Crack Dynamics in Dental Hard Tissues — Dr Masoud Hassan Zadeh Cracks: Treatment Options and Prevalence — Dr Masoud Hassan Zadeh

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