Semi-direct technique involving the laboratory by Dr J Van Rensburg

This case illustrates the advantages of fibre-reinforced composite restorations constructed in the dental laboratory. This technique will also make the construction of multi-unit bridges easier for the clinician.


Female, 35 years

Case history

A 35 year old lady patient. An acrylic partial upper denture was replacing her four upper incisor teeth. She had been wearing this denture for over 20 years. On examination the soft tissues covered with the denture were very red and inflamed due to the irritation of the acrylic denture. The patient was very keen to remove the denture and to have her missing teeth replaced with a fixed prosthesis. All treatment options were discussed with the patient and she was referred for an implant consultation. A scan and x-rays revealed that there was insufficient bone available and a bone graph procedure was advised prior to implant placement. This was not acceptable to the patient and she requested me to proceed with the FRC bridge treatment option. The option of a porcelain fused to metal bridge was also considered but rejected because of the excessive damage done by the preparation of the abutment teeth.


Two small occlusal rest preparations were made occlusal and mesial of the UR4 and UL4. No other preparations were considered necessary. A Putty wash impression (Codent) was taken of the upper teeth as well as a lower alginate impression. Futar Retar D was used to register the bite. The impressions were sent to the dental technician for the construction of a partially completed FRC bridge. Clear instructions were given to the technician and sufficient fibre reinforcement was encouraged. Note the vertical reinforcement for the pontics on the reliable fibre frame made by the dental technician. The whole bridge was completed on the model except for the labial aspects of the UL2 and UR2. These areas were left uncompleted (or grooves can be created on the labial surfaces) for to insertion of labial fibres, bonded to the labial and mesial aspects of the canines by the clinician. The bridge was cemented with a dual cure resin cement ( Multilink Automix with Primer A&B from Ivoclar-Vivadent). The property of bonding to composite allowed the clinician to add extra retention and reinforcement to the bridge by inserting additional fibres in situ. This is another advantage of the FRC bridges over conventional porcelain and porcelain fused to metal bridges. For this very reason repairs and more reinforcement, if necessary, can always be carried out in the mouth at any stage. In my opinion this technique is superior to the metal alloy resin bonded bridges ( or Maryland Bridges), sharing the minimally invasive property of these treatment options.

  • Partial acrylic denture

  • Note the redness of the soft tissues due to the irritation of the acrylic denture

  • Missing anterior teeth

  • Fibre Frame constructed by technician

  • Vertical reinforcement for the pontics

  • Bridge ready to be placed

  • Try-in in the mouth- ready for cementation

  • Extra fibre reinforcement bu of the canines -into the grooves on the laterals

  • Final completion

  • Palatal view