I think that my periodontist has neglected my gum recesion problems for 4 yrs. he is not approachable. what to do now besides changing from him?

Second opinion: Trust is very important in the doctor patient relationship. If you have questions about your treatment then get a second opinion.

Change: What's wrong with changing? If you are not satifsfied with his opinion as to what should/should not be done, seek another opinion from another periodontist. That's the purpose of other opinions...The patient and doctor can get on the same page.

Ask questions: When gum tissue recedes two major things can happen: (1) you get loss of attachment which can eventually lead to tooth loss and (2) you get expose root surface which increases cold sensitivity. Aesthically, recession can look unsightly especially in areas visible when smiling. I'd talk with your periodontist about this. He/she could have a very good reason why your recession has been untreated.

Contact general DDS: Speak with your general dentist. You should be alternating recall visits with the periodontist and general dentist and the general dentist may have a baseline of your recession photographed. If you feel that you need further periodontal intervention, have your general dentist speak with the periodontist about your concerns or ask for a referral to another practitioner.

If you are not happy: not comfortable or satisfied with your current periodontist, remember the choice is yours and you may try another periodontist near you.