Okla. Stat. tit. 85A, § 93

On its own initiative at any time that compensation payments are being made without an award, the Workers' Compensation Commission may, and in any case if the right to compensation has been controverted, if payments of compensation have been suspended, or if an employer seeks to suspend payments made under an award, or on application of an interested party, the Commission shall make such investigation, cause such medical examination to be made, hold such hearings, and take such further action as the Commission deems proper for the protection of the rights of all parties.