Abstract: A torque wrench for preventing transmission of torque in excess of a threshold level to avoid damage to replaceable scaler tips and hand pieces of ultrasonic dental instruments. The torque wrench has a housing with a core seated therein, with a cam mechanism or spring engagement between the core and the housing, such that the core may remain stationary when the housing is rotated passed the threshold level of torque. The core has an axial bore to receive a connecting shaft of a scaler tip, such that a working end and a functional shank of the scaler tip are received in a chamber of the housing, with the housing acting as an isolation cage for the scaler tip.

Abstract: A cassette has a top joined with a releasably attached double hinge to a bottom. An interior region can be filled with dental/medical instruments for sterilization and/or storage. The instruments can be supported by pre-arranged supports and retaining members. A practitioner can configure the arrangement in the cassette in accordance with his/her preferences.