Oh the dummy debate! lol.  I have had babies who have had a dummy and who haven't, so I pretty much know all the pros and cons of dummies! lol.  Backwards and inside out if that helps.

Pros: 

1.  They help to soothe an upset baby.
2. If you are breastfeeding, you can give your breasts a break from the 'chewing' your baby will do for comfort so they can repair ready for the next feed.
3. Bubs can comfort suck in anyones arms

Cons:

1. They can become expensive
2. They are easily lost
3. You miss out on sleep if your baby cries in the middle of the night and you have to get up to give it to them (experience has taught me I got less sleep with my dummied babies than with my non dummied babies).
4. They need to be sterilized, especially for young babies.
5. They can break/perish quickly, especially when bubs is teething.

My last 2 (out of 5) children have rejected a dummy, and as I have breastfed them, they used me until they found their thumbs.  A much better solution, and the oldest of those 2 only sucks her thumb when she is tired.  Current bubs sucks hers when I refuse to let her comfort suck on me! lol. Still not getting much sleep though, but that's an entirely unrelated issue.

Whatever you decide, do your research into what is best for bubs.  Compare brands and be prepared for you to spend a small fortune finding the right one for your baby.

for me i never wanted to use a dummy but i ended up using one with all my babies, they were wanting to suck all the time (breastfed) and it was hurting my nipples so i gave them a dummy when they needed soothing and not feeding.

they all grew out of the dummy by 9 months and refused it. which sometimes sucks cos i become the dummy lol

xoxo

Based on my experience, the use of pacifiers/dummies is sometimes up to the wee little one.

My son needed a pacifier from day 2 of life. We were still in the hospital and I've already breastfed him, burped him, and his dad had already changed his diaper and he still wouldn't stop crying. We called a nurse in and the nurse suggested a pacifier. Sure enough, it was the answer. I still sucessfully breastfed him up to 12 months even though hew as a heavy pacifier user. At 18 months he only used it at nap/bedtime, but then several months later he went back to constant use. He finally parted with pacifiers at 2 1/2 years old.

Now my twins (now 19 months) is a whole different story. We were prepared with pacifiers even before they were born, but they didn't want anything to do with it. We put pacifiers in their mouths and out they came flying out.  lol

Anyway, based on readings I've done and based on my children's pediatrician, they don't really cause any damage to the teeth. And if your baby a 'sucker' and not a self-soother, a pacifier is the only answer. We had several at home and several in each bags for my son because if we were caught without one, it was the end of his world as we knew it!

Hey my son doesn't have a problem with his dummy. He tries to stick his whole fist in his mouth before he goes to bed at night and drools EVERYWHERE so I stick a dummy in his mouth. Usually after 5 or 10 minutes he falls asleep, the dummy falls out of his mouth beside him and he sleeps all night without it. So I use it briefly as a means of keeping his hands out of his mouth. As last time he successfully made himself throw up lol

The main reason why I wont use one is because it reduces the time baby sucks and can affect milk supply.

I do not know the pros and cons of it, but I know I was a dummy sucker and my siblings werent.
My son wouldnt take a dummy for the first 3 months until his teething started and now he loves it.

I try to just give it to him when he is distressed, in pain, or tired. It is a good sleeping aide but as it has been said already if they need it to sleep and it gets lost and they need it to go back to sleep, you have to find it.
The best I can suggest for that is having a few of the same dummy handy so you know where one is if the other gets misplaced.
If the change table is close to the cot, I have one sitting there if I cant find his dummy.

1 con I can think of though is sometimes its hard to break that depencancy on the dummy when they are older.

my eldest daughter is a thumb sucker and my son was a dummy sucker, my youngest girl is a finger sucker (my girls just gagged on the dummy).

pros- quick way of getting baby quiet. it can be taken away (eventually and with a lot of planning and encouragement, and stress) whereas a thumb obviously cant.

cons- baby becomes dependent on them as a sleep cue- if it gets lost then your in trouble, if baby wakes in the middle of the night and needs it to go back to sleep, then you have to get up to find it (I often had to get up in the middle of the night to find lachlans dummy).  it may be difficult to get rid of, you have to replace them frequently, toddlers may regress at times of stress and want the dummy back once it has been given up.  if your baby refuses the dummy, you cant force it.

if i could do my time over, i would use the dummy with my son only when he really needed it to settle, and get rid of it at an early age.  He had his dummy until he was 3 1/2 and was highly dependent on it- he did give it up but then found one when our youngest was born and regressed.  i think its better to teach good cues for sleep that can be maintained by the baby, without you needing to get up in the middle of the night.

hope this helps.

Both my girls used dummies and they were a blessing in our house, some babies just want to suck even though they were not particulary hungary as i soon learned with both my bubs which led to sore cracked nipples because they failed to latch correctly because they were only looking for the comfort of sucking. I used them as a sleeping aide as i only gave it to them in thier cots so they soon learned that the dummy meant sleep. When they were both 2 and a half they were old enough to understand that it was time to let them go and the dummy fairy took the dummy away overnight and lest a little gift in it's place and we have not had an issue since!!

Good luck.