Can I still do dentistry if I take 3 years to complete A levels?

My AS results came through yesterday and unfortunately they were low
Bio: C
Maths: E
Chem: E
English Lit: B

Because of these AS results my teachers won't predict me the grades I need to apply for dentistry, therefore I am considering retaking my AS levels. That means I would complete my A Levels in the space of 3 years rather than two. Does this mean I won't be accepted by uni's for dentistry? Even if I was to come out with AAAA next year when I resit, will I still be rejected? Does anyone know any pathway I can take to get into dentistry now? I really appreciate any help I can get right now (:

Same here. I did really bad, so I decided to repeat AS level and work hard. I want AAA.. I checked at Manchester university website and I clicked the entry requirements and it didn't say anything about how many years of A levels they accept. So I suppose I have a bit of chance there..