AIIMS offers MDS Orthodontics, MDS Prosthodontics, MDS Conservative Dentistry and Endodontics, MDS Oral and Maxillofacial Surgery and MDS Pedodontics and Preventive Dentistry. For all these courses, you should have completed your BDS from a University recognised by the Dental Council of India along with mandatory rotatory 12 months internship. Admissions are conducted through the entrance examination held twice a year  in January and July by All India Institute of Medical Sciences. So going by this, if you complete BDS from NIMS, you can study MDS in AIIMS.