Tennessee Code Title 8. Public Officers and Employees § 8-34-614

(a) Any teacher who had retired prior to July 1, 1972, and returned to teaching service, and was ineligible to make further contributions to the Tennessee teachers' retirement system, shall now be eligible to claim such years for retirement credit; provided, that such teacher has not reached sixty-five (65) years of age; and provided further, that a lump sum deposit be made which would equal the amount that such teacher would have contributed had such teacher been a member of the system, plus interest at the rate designated in § 8-37-214.

(b) Such amounts so deposited shall become a part of the teacher's accumulated contributions in the same manner as if the contributions had been timely paid.

(c) Any creditable service established under these provisions shall be added to such member's previously established creditable service, and upon subsequent retirement, the teacher's retirement allowance shall be based on such member's compensation and creditable service before and after the period of prior retirement.