ORE Part 2 · Dental Manikin (DM) guide
Class IV Composite Build-Up
In the Class IV (Class 4) composite exercise, you start from a fractured upper incisor, prepare continuous margins, line where needed, rebuild the corner in composite, then finish and polish. It tests fine handpiece control, clean layering, and copying the contour of the neighbouring incisor without flash or overhangs.
Our video demonstrates this on an upper central incisor (21). In the exam, the tooth and exercise are set on the day.
What examiners look for
- Smooth fracture surfaces with no unsupported enamel and no unnecessary tooth loss
- A continuous, well-defined margin all round, which the examiner may ask to see
- A thin, smooth lining confined to the pulp-horn area and kept off the enamel margins
- A void-free restoration with a sound contact and a shape that matches the adjacent incisor
- A smooth tooth–filling junction that a probe doesn't catch on
- No damage to the adjacent tooth or gingiva
Common mistakes
- Pressing too hard with the margin bur and cutting a ditch instead of a chamfer
- Letting lining material spread onto the enamel margins
- Leaving flash or a step between filling and tooth
- Finishing from tooth to filling, or stopping a disc mid-stroke
- Touching the gingiva or adjacent tooth with discs or burs
Candidate questions
What's checked before the composite goes on?
You may be asked to show the examiner your margins and lining. Margins should be continuous and smooth, and the lining thin and confined to the pulp-horn area.
How do I avoid probe catches at the margin?
Remove all flash and finish in strokes from the filling towards the tooth, so a probe glides smoothly across the junction.
How do I match the adjacent tooth?
Use the neighbouring central incisor as your reference for incisal height and labial inclination, and copy its angles in stages.