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Hinged single piece putty index for preclinical demonstration of tooth preparation for fixed partial dentures and crowns.

INTRODUCTION
Different types of indices are being used for assessment of tooth preparation. All these indices are used to visualize tooth preparations in a particular plane. A single versatile index which could help to visualize tooth preparations in different planes is non-existent. The need for fabrication of such an index and its reliability is of utmost important to provide quality tooth preparations.


PURPOSE
The purpose of the study is to fabricate a hinged single piece sectioned index which could be used to visualize tooth preparation in different planes and check its reliability in-vitro on phantom models.


MATERIALS AND METHODS
Ten preclinical students were selected in random for preparing three teeth each. The three teeth preparations are classified as Group A, Group B and Group C based on the non-usage of index, usage of sectioned index and hinged single piece sectioned index respectively. Students were made to do provisional restorations after the tooth preparations. Then a questionnaire was given to students to score the duration/accuracy/comfort during tooth preparation and duration/accuracy of provisional restorations for each of the Groups A,B and C.


RESULTS
In Group C, 90% of students found the final preparation to be very accurate. The time taken for fabrication of provisional restoration using sectioned hinged index by 60% of Group C students was 20 to 30 min.


CONCLUSION
This hinged index is a viable option when accuracy of tooth preparation and speedy fabrication of provisional restoration is required.