California Code, Health and Safety Code - HSC § 1367.68

(a) Any provision in a health care service plan contract entered into, amended, or renewed in this state on or after July 1, 1995, that excludes coverage for any surgical procedure for any condition directly affecting the upper or lower jawbone, or associated bone joints, shall have no force or effect as to any enrollee if that provision results in any failure to provide medically-necessary basic health care services to the enrollee pursuant to the plan's definition of medical necessity.

(b) For purposes of this section, “plan contract” means every plan contract, except a specialized health care service plan contract, that covers hospital, medical, or surgical expenses.

(c) Nothing in this section shall be construed to prohibit a plan from excluding coverage for dental services provided that any exclusion does not result in any failure to provide medically-necessary basic health care services.