What is the Code to use for Bac Decon per Qd?

Leonore, I assume you are referring to bacterial decontamination via laser. The ADA does not have a code specific for this adjunctive procedure. Your options are either to include this with your fee for scaling and root planning with use of D4342 or D4341, or you may use the “catch-all” code D4999 (Unspecified periodontal procedure, by report) – and include a narrative describing bacterial decontamination. Either way, the benefits will be limited by the contract. Very few payors reimburse for D4999 and if you elect to increase your fee of periodontal therapy, it likely would be greater than the “usual and customary” limits of most plans. I have seen practices do both: An increased fee to the periodontal therapy, or a separate fee with D4999.