Bridgework 1

Question 1

How does a bridge differ from a removable partial denture in design and function?

Answer 1

A bridge is fixed to natural teeth or implants and replaces missing teeth without being removed by the patient. In contrast, a removable denture replaces soft tissue and bone and must be removed for cleaning.

Question 2

What are the two major categories of bridgework and how do they differ in terms of retention and support?

Answer 2

adhesive (minimal prep) and conventional (full prep) bridges differ in how they are retained—adhesive uses bonding to enamel, while conventional uses full crown retainers.

Question 3

In what systemic and psychological cases may bridgework be indicated?

Answer 3

when appearance, speech, and function are compromised. It may also help patients with systemic diseases like epilepsy (avoid removable appliances) and in those with psychological distress from tooth loss.

Question 4

What local oral features support the use of bridgework?

Answer 4

Suitable local conditions include large or heavily restored teeth, favourable abutment angulation, and favourable occlusion which help in supporting a stable and functional bridge.

Question 5

Why is patient cooperation and medical history vital when considering bridgework?

Answer 5

Poor oral hygiene, high caries risk, periodontal disease, and large pulps contraindicate bridge placement. An uncooperative patient may compromise success through inadequate maintenance.

Question 6

Which local factors suggest a poor prognosis for bridge placement?

Answer 6

High risk of further tooth loss, poor abutment prognosis, long edentulous spans, ridge defects, tilted teeth, poor periodontal or periapical health—all reduce bridge longevity and success.

Question 7

Define and differentiate the terms: abutment, pontic, retainer, connector, saddle, edentulous span, pier, and unit.

Answer 7

Abutment: Supports the bridge.

Pontic: Replaces missing tooth.

Retainer: Crown or restoration attached to pontic.

Connector: Joins retainer and pontic.

Saddle: Ridge beneath pontic.

Edentulous span: Gap being restored.

Pier: Intermediate abutment between two pontics

Unit: Each component (pontic or retainer).

Question 8

Compare fixed-fixed and cantilever bridge designs with examples.

Answer 8

Fixed-fixed uses two retainers (e.g. retainer–pontic–retainer), offering stability. Cantilever uses a single abutment (e.g. retainer–pontic), reducing stress but suitable only for certain clinical scenarios like anterior teeth.

Question 9

What is the concept of resin bonded bridgework and when is it typically used?

Answer 9

RBB uses minimal or no preparation and is bonded to enamel using resin cement. Common for young patients or as provisional restorations. It includes metal (CoCr) and ceramic (zirconia) wings.

Question 10

What are the main advantages of RBB compared to conventional bridgework?

Answer 10

Minimally invasive, often no anaesthetic needed, cost-effective, fast, and less destructive if it fails. Suitable for interim or definitive restorations.

Question 11

What clinical issues can arise with RBBs?

Answer 11

Technique-sensitive, prone to debonding, possible metal shine-through, no trial phase, risk of chipping porcelain and occlusal interference.

Question 12

Which patients are ideal candidates for RBB, and who are not?

Answer 12

Ideal: young patients, good enamel, large abutments, low occlusal forces.

Contraindicated in bruxists, long spans, poor enamel, and high tissue loss.

Question 13

How does comprehensive examination influence RBB planning?

Answer 13

Assess bruxism, occlusion, soft tissues, and periodontal status. Use mounted models and wax-ups. Evaluate abutments and ensure patient can maintain hygiene.

Question 14

What are key considerations in direct RBB fabrication and when is it used?

Answer 14

Useful in emergencies or trauma. Pontic may be natural tooth or acrylic. Often done chairside with minimal prep.

Question 15

Why is lingual coverage crucial for indirect RBB bonding success?

Answer 15

It maximises enamel surface area for bonding. Ideal coverage is 0.5 mm supragingival. Shine-through should be avoided near incisal edges.

Question 16

Why is a cantilever design often preferred anteriorly?

Answer 16

Anterior teeth have divergent guidance paths; cantilevers simplify force distribution and are more conservative.

Question 17

How do existing restorations influence RBB prep?

Answer 17

Composite can be retained or replaced. Amalgam reduces bond strength and may require removal. Enamel preservation is key.

Question 18

What are the differences between anterior and posterior RBB preparations?

Answer 18

Anterior: often no prep or minimal (cingulum rest, chamfer)

Posterior: may require occlusal rests and wrap-around with proximal grooves.

Question 19

When is temporisation necessary for RBB preps?

Answer 19

Only if dentine is exposed or tooth is sensitive. Temporary options include RPDs or bonding agents, with quick bridge fitting to prevent tooth movement.

Question 20

How is the fit surface of an RBB retainer treated for optimal bonding?

Answer 20

Made of CoCr or NiCr alloy, sandblasted with 50-micron aluminium oxide for micro-mechanical retention.

Question 21

What are the detailed steps in RBB cementation using Panavia?

Answer 21

Retainer: sandblast, clean, degrease.

Tooth: prophylaxis, isolate, etch (37–40% phosphoric acid), apply mixed primer.

Apply cement to retainer, seat it, remove excess, apply Oxyguard for 3 mins.

Question 22

What should be checked post-cementation and what aftercare is given?

Answer 22

check occlusion, ensure pontic has no heavy contacts. Teach oral hygiene using superfloss or interdental brushes to maintain bridge longevity.