It will be dismissed if you complete PTI. That will be the end of the matter and you will have no criminal record. If you do not complete PTI, you can have a trial, or work out a guilty plea, either of which will result in a criminal record unless you are found not guilty in trial, or unless the state decides there is insufficient evidence to try you (which is probably unlikely)
I agree with both the other lawyers but would like to add that you record should also be automatically expunged. However, it is always a good idea to follow-up with the court clerk to make sure that this was done. Good luck!
The benefit of successfully completing PTI is that your charge will be dismissed and you will NOT have a criminal conviction on your record. The arrest should also be expunged from your record as well and you can obtain a copy from the clerk of court to confirm that.