The Bachelor of Dental Surgery (BDS) and Bachelor of Medicine/Bachelor of Surgery (MBBS) are undergraduate degree programs, and while they are both in the health field, they are both quite unique. The MBBS, even though it is a baccalaureate degree, requires more training to actually begin practicing medicine in most countries.
Typically, the educational coursework, the admission policies, and in many cases, the additional education is not as rigorous with the BDS as compared to the MBBS. A person graduating with a BDS can actually begin practicing dentistry upon graduation. With the MBBS, the professional has to complete more training, the exams that are required to enter the program are quite difficult, and it can be quite competitive as well.
Furthermore, the program for the MBBS is a five and a half years compared with the BDS, which is five years. To answer your question, the BDS allows professionals to get out there and practice dentistry while the medical degree requires more training and certification (post graduate education), so no, it is not a higher degree, even though it requires more training.