The American Dental Association has said it's a matter of clinical judgement of the dentist. It is appropriately reported as D4910, but if the treating dentist determines the patient can be treated with routine prophylaxis, then D1110 may be appropriate.

No, a patient who has undergone SRP (4341 or 4342) is a perio patient for life. They will forever be 4910, not 1110.

SRP is the therapeutic treatment applied to someone with clinical attachment loss (CAL, also known as bone loss), not just pocket depths but actual measured bone loss with radiographic indication. Once the patient has completed SRP, they move into the maintenance stage of 4910, typically every 3-4 mo for life. CAL is defined as the loss of attachment measured from the CEJ to the base of the pocket/sulcus. Even if pockets reduce to 1-3 mm depths the CAL remains. Even if the patient loses the teeth with the CAL, they still have a history of perio and are susceptible to further disease.

Note: The caveat is, you may have a patient with a healthy mouth, who does present with CAL, but notes the CAL is due to mechanical causes (i.e., history of aggressive brushing), and has no history of SRP, nor is SRP warranted, then 1110 is appropriate.

If a patient presents with inflammation, bleeding, build up, etc but does not present with CAL, this is not a perio patient. It is a patient with gingivitis and the appropriate treatment is 4346 (scaling in the presence of inflammation). Once the patient has been treated and depths return to normal, then they would follow up with 1110.

The difference between the two is CAL. If CAL is present, then it;s perio.

If SRP was performed on a patient without CAL, they were misdiagnosed. The proper treatment should have been 4346.

Sources:
Lang NP, Bartold PM. Periodontal health, J Clin Periodontology. 2018
Tonetti MS, Greenwell H, Kornman KS. Staging and grading of periodontitis, J Clin Peridontology. 2018
Caton JG, Armitage G, Berglundh T, et al. A new classification scheme for periodontal and peri-implant disease and conditions. J Clin Peridontology. 2018
Chapple ILC, Mealey Bl, et al. Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium. J Clin Periodontology. 2018

In the CDT Coding Companion it states:
Clinical Coding Scenario #10: Periodontal Maintenance Therapy and Prophylaxis Visits Following either surgical or non-surgical periodontal therapy, the patient is placed by the treating dentist on a program of scheduled periodic periodontal maintenance (D4910) visits, which could be at various intervals (e.g., 2, 3, 4, or 6 months) depending on the patient’s clinical condition. The D4910 periodontal maintenance procedure includes removal of bacterial plaque and calculus (mineralized deposits) from subgingival and supragingival tooth surfaces, site- specific scaling and root planing, and coronal tooth polishing. Between these scheduled periodontal maintenance visits, the patient is also seen by the dentist for routine dental prophylaxis (tooth cleaning procedures). May the dentist code and bill for the prophylaxis procedure (D1110 or D1120) or is this prohibited as a duplication of existing services under D4910? Nothing in the D4910 or the D1110 (or D1120) code nomenclatures or descriptors make these procedures mutually exclusive. If the dentist determines that the patient’s periodontal health can be augmented with periodic routine prophylaxis procedures (removal of plaque, calculus, and stains from the tooth structures for the purpose of controlling local irritational factors), then this service should be performed and reported as D1110 or D1120, depending on the state of the dentition. Does it make any difference if the reporting dentist for prophylaxis (D1110 or D1120) is the same dentist providing periodontal maintenance (D4910)? No. The dentist should code and report for the services provided regardless of the provision of other services by the same or a different dentist. Will both procedures be reimbursed by the patient’s dental benefit carrier? Reimbursement will depend upon the dental benefit plan language and the contractual policies governing covered benefits.

*SRP is to clear the gums of anything that has been stuck up and allow the gums to heal to a healthy pocket size. If the patient has been doing what was necessary to take care of there gums and the dentist say their gum health has improved and as long as there is no bone loss then yes they can go back to a prophy. The insurance will want to see proof of the gum health (most likely). Yes there will be cases that will not be able to go back to a prophy because the gums will not be able to heal or they have entirely too much bone loss. Its best to see what the insurance company says about it plus you can always submit a preauth to see what they say about switching back over to normal maintenance.

you can go back to D1110 anytime

Yes, but you typically need clear and concise documentation to show the gum health has improved. The best thing is to call and speak with the insurance company. They can provide you with specifications of that code in that particular plan. There may be a certain period of time they have to be on SRP maintenance. Make sure to also check the date they can have the regular prophy. You don’t want to run into any frequency issues. You may need need more X-rays etc…

No they cannot. A patient who qualifies for SRP has to have boneless (and other factors), and is followed by a lifetime of 4910 recalls. 1110 is for a routine prophy with NO boneless. 4910 is Periodontal Maintenance, which is for maintaining bone levels. Therefore once a perio maintenance pt, always a perio maintenance pt. The goal of perio maintenance is to maintain bone levels!