Maryland bridges.
A resin-bonded bridge replaces a missing tooth with almost no preparation of the abutments. It is the most conservative fixed option available, and the one most dependent on case selection.
Where it works
The classic indication is a missing anterior tooth — frequently a congenitally absent lateral incisor — with sound, unrestored, enamel-covered abutments and light occlusal demand on the pontic.
It is also valuable as a medium-term solution in a young patient where implant placement must wait for skeletal maturity, precisely because it preserves the abutments for whatever comes later.
Where the abutments are heavily restored, where the occlusion loads the pontic heavily, or where parafunction is evident, the design is being asked to do something the bond cannot sustain.
Single wing or two
Contemporary practice increasingly favours a single-retainer cantilever design over the traditional two-wing bridge.
The reasoning is that two abutments with differing mobility place the restoration under repeated stress at the bonded interfaces, and one wing debonds silently while the other remains attached — allowing caries to develop unnoticed beneath the loose retainer.
A single retainer either holds or debonds visibly, which is a considerably safer failure mode. Where a cantilever is feasible, it is usually the better design.
Preparation
Minimal, and confined to enamel. The bond to enamel is what the entire restoration relies on, and exposing dentine at the margins compromises it materially.
Some preparation is generally still worthwhile: a defined path of insertion, a cingulum rest or small grooves to resist displacement, and a definite margin so the wing has a positive seat rather than feathering out onto the tooth.
Adequate wing area matters. A retainer that is too small has too little bonded surface to resist the forces on the pontic.
Material and cementation
Zirconia wings have largely displaced cast metal for anterior work, being less visible through the abutment and avoiding the greying that a metal retainer can produce.
Bonding follows the zirconia protocol — air abrasion with fine alumina and a phosphate-monomer primer, then a resin cement, under isolation. Contamination after try-in must be actively cleaned rather than rinsed.
Isolation is not optional here. This is the restoration most dependent on the bond of anything on the Rx form, and a compromised field produces a predictable debond.
Managing expectations and review
Debonding is the characteristic failure, and patients should be told at the outset that it is a possibility rather than discovering it as a surprise. A restoration that can be rebonded is a minor event when it was anticipated and a complaint when it was not.
Review the retainer at recall. With a two-wing design in particular, check each wing individually — one can debond silently while the other holds, and caries develops unnoticed beneath the loose retainer.
Where a patient's occlusion or parafunction makes repeated debonding likely, that is a case for a different restoration rather than for repeated recementation.
What to put on the prescription
Mark the abutment and pontic on the design chart and state clearly whether you want a single-retainer cantilever or a two-wing design.
Name the wing material, give the shade with the guide used, and note the abutment shade — a wing bonded to the lingual affects how the abutment reads from the front.
State the occlusion on the pontic and whether it carries any excursive contact. If it does, that is worth discussing before the case is made.
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