i think as long as you attempt to clean her teeth once during the day, every few days or so, you're doing pretty good. i almost never cleaned my older daughter's teeth more often than a couple of times a week until she was two and a half.... she's four now and just had her first dentist appointment and got a perfect check up! i wouldn't worry about it. we actually clean our younger daughter's teeth more regularly now but only because the four year old has her routine now and the two year old wants to do everything her sister does!
at around 12 months, the routine was kind of like this (obviously the times varied depending on the day, but we tried!):
dinner around 6
baths around 6:45
bottle with scripture stories around 7-7:15 (depending on how long we played in the bath!)
prayers and lights out around 7:45
now the routine at 2 and 4 years old is more like:
dinner around 5:30-6
baths around 6:30
scripture stories and warm milk around 7-7:15
teeth brushing when milk is done
prayers
lights out around 7:30-7:45
7:50 put the 2 year old back into bed
7:52 put the 2 year old back into bed
7:55 put the 2 year old back into bed
7:56 yell at the 2 year old and threaten 2 year old with the gypsies if she gets out of her bed again
7:59 turn up the monitor and listen for sounds of 2 year old getting out of bed
8:05 huge sighs of relief that no sounds are heard from the 2 year old!!!
seriously, my 2 year old can NOT go to sleep at night without being threatened with being sold to the gypsies! have you ever watched bill cosby himself? i highly recommend it! he talks about how his children can NOT go to bed without their nightly beatings....
ANYWAY.... we only very recently threw teeth brushing into the routine between milk and bedtime and both my kids have healthy teeth.