Assessment of the amount of remaining coronal dentine in root-treated teeth.
OBJECTIVE
There is currently no standardised technique to measure the amount of coronal dentine remaining in a root-treated tooth after crown preparation. The aim of this study was to develop a method of measuring remaining coronal dentine in root-treated teeth and to propose an index for grading tooth restorability.


METHODS
The study recruited 20 patients who had completed molar endodontic treatment at the Eastman Dental Hospital and had been prescribed an amalgam coronal-radicular core with a full coverage cast restoration. Using a series of interlocking special trays and impressions, a method was devised to produce a cast of the amount of remaining dentine coronal to the finish line after crown preparation. This cast was scanned using a laser profilometer and the volume of remaining dentine was calculated. A tooth restorability index (TRI) was developed to assess the strategic value of the remaining dentine. The TRI allowed scores of 0-3 in each sextant with a maximum score of 18 per tooth.


RESULTS
Twenty teeth were scored by three examiners and the TRI scores varied from 2 to 13. The volume of coronal dentine varied from 61.73 to 232.22 mm(3).


CONCLUSIONS
A tooth restorability index has been devised to assess the strategic value of remaining dentine. A Kappa statistic was calculated to produce values of 0.584, 0.688 and 0.720, giving moderate-good agreement between the examiners.
Department of Conservative Dentistry, Eastman Dental Hospital and Institute for Health Care Sciences, 256 Grays Inn Rd., London WC1X 8LD, United Kingdom.
R B
RB
Bandlish
A V
AV
McDonald
D J
DJ
Setchell
D003442:Crowns; D003723:Dental Amalgam; D003793:Dental Restoration, Permanent / Q000706:statistics & numerical data*; D003804:Dentin / Q000033:anatomy & histology*; D006801:Humans; D007834:Lasers; D003765:Models, Dental; D015588:Observer Variation; D009811:Odontometry / Q000379:methods* / Q000706:statistics & numerical data; D011446:Prospective Studies; D015203:Reproducibility of Results; D012390:Root Canal Therapy; D019228:Tooth Crown / Q000033:anatomy & histology*; D019231:Tooth Preparation, Prosthodontic
D003723:Dental Amalgam