Light based dental treatment device

A light delivery shaft assembly comprising:

• a delivery shaft extending between a proximal tip and a distal tip, the delivery shaft includes:
• a proximal shaft profile having a proximal light port configured for reception of therapeutic light from a light element;
• and
• a distal shaft profile different than the proximal shaft profile, the distal shaft profile having a distal light port configured to deliver therapeutic light received from the proximal light port;
• and
• a shaft fitting coupled with the proximal shaft profile, the shaft fitting includes a fitting profile complementary to an interior collet profile of a handle generator, the fitting profile configured to align the proximal light port with at least one light element of the handle generator.

A method for treating a tooth comprising:

• selecting a light delivery shaft assembly having a distal shaft profile corresponding to a cavity profile of the tooth;
• coupling the selected light delivery shaft assembly with a handle generator, coupling includes:
• positioning a shaft fitting of the selected light delivery shaft assembly within an alignment collet;
• operating the alignment collet to align a proximal light port of the delivery shaft assembly with at least one light element of the handle generator;
• and
• fixing light delivery shaft assembly to the handle generator with operation of the alignment collet.