An ultrasonic forceps comprises a housing, an acoustic assembly, and a tine. The housing joins the acoustic assembly and the tine to the forceps and permits the tine to pivot relative to the acoustic assembly. The acoustic assembly comprises a transducer, a waveguide, and ultrasonic blade, and a waveguide sheath. The transducer is configured to generate ultrasonic vibrations directing the ultrasonic vibrations to the waveguide. The waveguide communicates the ultrasonic vibrations distally to the ultrasonic blade. The ultrasonic blade is configured to vibrate in response to the ultrasonic vibrations generated by the transducer. When the tine is pivoted relative to the transducer, the tine is configured to move toward the ultrasonic blade. Tissue may be grasped between the tine and the ultrasonic blade. The tissue may be denatured when the ultrasonic vibrations generated by the transducer vibrate the ultrasonic blade, thus resulting in the tissue being cut and/or sealed.