Endocrowns: one piece, no post, more root left alone

A post does not strengthen a tooth. Its job is retention: it gives a core something to hold onto when too little natural tooth remains above the gum to do that on its own. Placing one means preparing a channel down inside a root canal, which removes dentine from the part of the tooth that is doing the structural work. That is the trade, and it is worth making when retention genuinely has nowhere else to come from.

An endocrown asks a different question: is there enough space inside the pulp chamber, plus enough surface to bond to, for the restoration to hold without going into a root at all. Where the answer is yes, the channel is never prepared and the root keeps the dentine it has. Edelhoff and Sorensen's measurements of preparation designs are a useful reference point for how much structure different approaches cost, with complete crowns removing 63% to 72% of coronal tooth structure against 3% to 30% for veneer and bonded designs.^[4]

A 2025 systematic review and meta-analysis set out to compare structurally compromised teeth restored with all-ceramic endocrowns against all-ceramic conventional crowns with or without post and core, requiring a minimum follow-up of three years. Five clinical studies met the criteria and four entered the analyses. Across 277 endocrowns and 246 crowns followed for seven years the pooled risk ratio for success was 0.93 with a confidence interval of 0.69 to 1.27. Across 420 endocrowns and 458 crowns at five years it was 0.96, interval 0.67 to 1.39.^[1]

Both confidence intervals cross 1, which is the statistical way of saying the study could not distinguish the two. That is a meaningful finding on its own terms, because the endocrown reaches it while leaving the root untouched. It is not a finding that endocrowns perform better, and the review does not claim one.

An overview synthesising nine systematic reviews on one-piece endodontic crowns found that survival and success at five years were high and similar to conventional crowns for ceramic and indirect resin versions, and that loss of retention was the main cause of failure, at similar rates for molars and premolars.^[2] De-bonding rather than fracture is a comparatively forgiving way to fail. It also means the two things that most influence longevity are within the clinician's control on the day: the quality of the bonded surface and how the restoration meets its opposing tooth.

An endocrown depends on the chamber and on the bond, so anything that removes either removes the option. Too little sound wall above the bone leaves nothing to seal a margin against. A chamber that is very shallow, or one already over-prepared during the original access, may not give the depth the design needs. A tooth acting as an abutment for a bridge or a partial denture carries loads the evidence base does not describe. And a bite that loads the restoration sideways is a poor setting for a retention design that depends on adhesion.

Saying which of those applies is the useful part of the consultation. A technique that suits most root-treated molars does not suit all of them, and the assessment is what separates the two.