Orifice barriers to prevent coronal microleakage after root canal treatment: systematic review and meta-analysis

Low technical standard of the root canal filling

The use of materials with low biocompatibility

Presence of microorganisms in the root canal system

Apical cysts formation

It provides an unbiased confirmation of data

It creates a new data set by combining prior studies

It has a lower error compared to a single study

It pools prior studies to generate a larger sample size

MTA

IRM

Amalgam

Dentine bonding agent

50%

10%

90%

76%

Placing a barrier of 2–3 mm thickness on clean dentine

Removing gutta-percha of the coronal 4 mm of the root canal

Filling the pulp chamber completely with a barrier material

Use a barrier only in combination with immediate restoration

Enlarge the coronal root canal third further to accept barrier materials

P Chen: Writing – original draft. Z Chen: Writing – original draft. Y-Y Teoh: Writing – original draft. OA Peters: Writing – review & editing; Writing – original draft. CI Peters: Writing – review & editing; Writing – original draft.