Anyone ever had Scaling and Planing done to their teeth?

My husband's parents didn't keep up with his dental care when he was younger so for the last few years we've been trying to get his teeth in shape as much as we can afford to do at one time. We spend thousands, but I'm starting to get really annoyed because we spent I think 600 on Scaling and planing and they seem to want to do it every year! If you charge hundreds of dollars to do intensive cleanup why do we have to do it each year. HELP!
--------------------
Ideally, Scaling & Root Planing should only have to be done once and that's it. Usually, the patient goes in, gets numb and the hygienst cleans below the gumline. The patient has to do some work too! Make sure your husband is brushing at least twice a day for two minutes each and FLOSSING EVERYDAY! He also needs to keep up with his cleanings; once a year is not going to cut it for someone who's got periodontial disease. Usually, after SRP they need to do another cleaning 6 weeks later and then sometimes the patient needs to come back every 3 or 4 months until the disease is under control. If your husband has been doing this, then you need to talk to your dentist and see what needs to be done to improve his oral health. Hope this information helps. Good luck.
Source