Friday, July 30, 2010

When should a dentist choose to adjust an opposing tooth when fitting a crown?

Patients often do not like it when a dentist 'adjusts' the occlusion of an opposing tooth when fitting a crown. Although often it is not neccesary or advisable to adjust the opposing tooth, sometimes it is advisable.

If the opposing tooth has drifted down because it was not held in occlusion by a tooth that was not restored in proper occlusion, then equilibrating it is a good idea before inserting a new crown. Also some opposing teeth can interfere with the excursions that a crown can make and adjusting an opposing tooth's cusp tip may be preferble to further adjusting a crowns cusps which may be needed to establish a proper 'centric occlusion'(resting occlusion). If this is not done cuspal interferences during excursions may cause a porcelain crown to chip.

2 comments:

  1. Bryan Leigh6:53 PM

    Thanks, Dr Spindel, for addressing my recent question on Allexperts, which clearly has led to your latest blog posting (30/7/10). Permit me to add that the lingual side of the tooth opposing my newly crowned molar was not simply adjusted at the cusp tip, but was substantially destroyed. I now have a high occlusal plane at #32, which traps my tongue when I talk. Can this be justified by assuming that a high crown was needed in order to accommodate a high nub largely formed of old amalgam in the prepared tooth? Thanks again for your time and attention. Bryan

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  2. Dear Bryan, It is hard to say without examining you why he chose to adjust your opposing tooth. It is possible that If he felt that he was overthinning the crown that he chose to adjust the opposing tooth so the crown would not have a perforation in it. Sometimes this happens if the tooth prepared for a crown was not reduced enough.

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