Resin-Bonded Fixed Dental Prostheses: DENT2001

• Resin-bonded fixed dental prostheses (FDPs) experienced fluctuating popularity since Rochette detailed splinting mandibular anterior teeth via perforated metal casting in 1973.
• The main objective of a resin-bonded FDP is to conserve maximal tooth structure while replacing missing teeth.

Resin Bonded Fixed Dentures

• Broad application of electrolytic etching of metal surfaces provides micromechanical retention for bonding metal to enamel.
• Precise and defined metallic engagement of the abutment and successful conservative FDPs require strong etched enamel to metal casting.

Developmental of Resin Bonded FDPs

• The earliest resin-bonded prostheses used extracted natural teeth or acrylic teeth as pontics, bonding to the proximal and lingual surfaces of abutment teeth with composite resin.
• Limitations to these pontics included short anterior spans, limited lifespan, composite resin bond degradation to the wire or mesh.
• These restorations are suitable only as short-term replacements.
• In 1973, Rochette introduced metal bonding to teeth using flared perforations in the metal casting for mechanical retention.
• Principally for periodontal splinting, this included pontics and was limited to mandibular teeth or situations with minimal occlusal contact.
• Perforation techniques include:
  • Weakening of the metal retainer.
  • Resin wear at the perforations.
  • Limited metal adhesion.
• Thompson and Livaditis at the University of Maryland developed electrolytic etching of cast base metal retainers, also referred to as "Maryland bridge".
• Chemical or gel etching became simplified techniques.
• Bond strengths degrade in a moist environment using both techniques.
• Etched-cast retainers offer advantages over cast-perforated restorations:
  • Improved retention due to resin-to-etched metal bond being stronger than resin-to-etched enamel.
  • Thinner retainers still resist flexing.
• Highly polished oral surface of cast retainers resists plaque accumulation.
• High-strength ceramics, especially zirconia, now help retain resin-bonded FDPS
• Restorations show better esthetics than metal retainers.
• There's a possibility of discoloration.
• There's good medium-term clinical performance
• Tensile bond strengths of noble alloy plating are slightly lower than those of electrolytically etched or particle-abraded nickel-chromium-beryllium alloys and can measure 18 to 30 MPa.
• Particle abrasion of the alloy surface before bonding or tin plating creates both a roughened, and higher surface that aids bonding.

Design Concepts

• Guidelines for optimum resin-retained FDP design have been empirically derived.
• Underlying restorations must cover as much enamel surface as possible without compromising occlusion, esthetics, or periodontal health.
• Initial etched-cast retainer designs used an "interproximal wraparound" concept to withstand occlusal forces and broaden bonding area.
• Enamel preparations involved creating occlusal clearance, occlusal/cingulum rests, and reducing lingual/proximal height of contour for proximal extensions.

Advantages of Resin Bonded FDPS

• Minimal tooth structure removal.
• Minimal risk of pulpal trauma.
• Anesthesia not usually required.
• Supragingival preparation.
• Easy impression making.
• Generally, no interim restoration required.
• Reduced chair time.
• Reduced patient expense.
• Rebonding possible.

Disadvantages of Resin Bonded FDPS

• Reduced restoration longevity.
• Enamel modifications required.
• Space correction is difficult.
• Good alignment of abutment teeth required.
• Esthetics compromised on posterior teeth.

Indications of Resin Bonded FDPS

• Replacing missing anterior teeth in children and adolescents.
• Short edentulous span.
• Unrestored abutments.
• Replacing a single posterior tooth.
• Significant clinical crown length.
• Excellent moisture control.

Contraindications of Resin Bonded FDPS

• Parafunctional habits.
• Long edentulous span.
• Restored or damaged abutments.
• Compromised enamel.
• Significant pontic width discrepancy.
• Deep vertical overlap.
• Nickel allergy.

Fabrication of Resin Bonded FPDs

• Attention to detail in the following three phases is vital for the fabrication of resin-bonded FDPs:
  • Preparation of the abutment teeth.
  • Restoration design.
  • Bonding

Preparation of the abutment teeth.

• In anterior teeth, the procedure is similar in many ways to the lingual reduction needed for a pinledge preparation, but reduce the amount reduce because the enamel shouldn't be penetrated
• The casting should extend onto both mesial and distal surfaces to improve resistance and retention where possible. Mandibular incisors make this possible due to open embrasures and tooth shape.
• The the size and shape you use for grooves are essential for rentention, Narrower with flat parallel sides is more effective.
• The fundamental design for the posterior resin-bonded FDP includes
  • The occlusal rest, to aid displacement
  • The retentive face used in resistance to displacement
  • The proximal wrap
  • Proximal slots for resistance
• Typically There are distinct differences exist between maxillary and mandibular molar teeth only on the lingual surfaces
  • Preparing lingual tooth can be achieve through the use of 1 plane -Maxillary molar tooth require 2 plans due to the functionality

Design of Restoration

• A cantilever pontic design for resin-bonded FDPs is advised within the anterior region and is especially good in the the replacement of lateral incisors.
• Selection is rooted in better retention and better better aesthetics.
• Cantilevered designs offer benefits, helping to simplify
  • simplifies preparation.
  • Helps to avoid difficulties with the oclussion
  • Is effective on moblie teeth

Resin Bonded FDP Abutment

• If a singular cantilevered resin-bonded FDP fails, it falls out of the mouth
• To replace two mandubilar incisors it is recommended to create 2 sparate FDPs, Connecting them will cause failure

Explores resin-bonded fixed dental prostheses (RBFDPs), including design principles. Berkman ALBAYRAK is mentioned as an assistant professor. The content references the textbook with Chapter 26 on Resin Bonded Fixed Dental Prostheses.