The reason the third baby tooth was not extracted at this stage was to provide support to the reimplanted tooth.
The report says the dentist "removed teeth 53 and 63. However he removed tooth 26 by mistake instead of tooth 65. Tooth 26 is immediately behind tooth 65".
"He realised his error immediately and reinserted the tooth 26 back into the socket.
"On April 21st [2015, Dr B] started root canal treatment on tooth 26. [Dr B] has referred [the girl] to a specialist endodontist to complete the root canal work on tooth 26.
"Currently tooth 65 still has not been removed and the orthodontist is considering options.
"ACC [the Accident Compensation Corporation] has been informed and have accepted the claim as a treatment injury. [Dr B] has offered to pay any additional fees in the attempt to keep tooth 26 and if it becomes unsaveable in the short or long term he has offered to pay the cost of an implant."
Mr Hill found the dentist had breached the code of patients' rights by failing to provide services with reasonable care and skill.
He recommended the dentist apologise to the girl and that the Dental Council consider if a review of the dentist's competence is warranted.