Application Techniques

For the construction of a porcelain jacket crown it is essential that there is a clearance of 1.5mm between the root preparation and the opposing teeth in all positions of the mandible, otherwise the crown will be weak or contact the opposing teeth and will break. Always supply a bite and opposing model.

Remove sufficient tooth substance labially to allow a good covering of porcelain, otherwise the cement will show through and the crown will be weak.

Always make a good cervical ledge for a jacket crown, or the porcelain will chip or crack. Use free flowing material, otherwise you may burst your crown when cementing it. Bonded crown preparations should have cervical ledges buccally and interstitially. Buccal edgeless preparations should be subgingival to allow for a narrow metal collar.

Do make sure that silicone putty is fully set and dry prior to taking the perfecting wash impression.

A temporary auto-polymerised acrylic splint should be used to prevent migration and over eruption of the abutment teeth whilst bridges are being made.

Review Precision Attachments and Crown and bridgework