No RCT evidence to determine best technique for exposing displaced eye teeth

Permanent canine teeth in the upper jaw usually erupt into the mouth between the ages of 11 to 12 years. In 2% to 3% of young people, the canine teeth fail to erupt (grow down) and become displaced in the roof of the mouth (palate).This can leave unsightly gaps, cause damage to the surrounding roots (which can be so severe that neighbouring teeth are lost or have to be removed) and, occasionally, result in the development of cysts.

Management of this problem is both time consuming and expensive. It usually involves surgical exposure (uncovering), followed by fixed orthodontic braces for two to three years, to move the canine into the correct position. Two surgical techniques are routinely used in the UK: the closed technique involves uncovering the buried tooth, gluing an attachment onto the exposed tooth and repositioning the palatal flap. Shortly after surgery, an orthodontic brace is used to apply gentle forces to bring the canine into its correct position within the dental arch. The canine moves into position beneath the gum. An alternative method is the open technique, which involves surgically uncovering the canine tooth as before, but instead of placing an attachment onto the exposed tooth, a window of gum from around the tooth is removed and a dressing (pack) placed to cover the exposed area. Approximately 10 days later, this pack is removed and the canine is allowed to erupt naturally. Once the tooth has erupted sufficiently for an orthodontic attachment to be glued onto its surface, orthodontic braces are used to bring the tooth in line with the other teeth.

What was the research?

A systematic review of the evidence to find out whether it is better to use an open or closed surgical method to expose eye teeth (‘canines’) that have become displaced in the roof of the mouth.

Who conducted the research?

The research was conducted by a team led by Nicola Parkin from the University of Sheffield, on behalf of Cochrane Oral Health. Philip E. Benson, Bikram Thind, Anwar Shah, Ismail Khalil and Saiba Ghafoor were also on the team.

What evidence was included in the review?

The evidence in this review is up-to-date as of February 2017. The authors found three relevant randomised controlled trials, involving 146 participants who had eye teeth displaced in the roof of the mouth, either on one or both sides. The majority of participants were female and the average age in the studies ranged from 14 to 17 years. Two studies were designed in a way that made them likely to be biased.

What did the evidence say?

The results from three studies were combined. It was found that one technique did not seem to have an advantage over the other for ensuring the movement of the tooth into the correct position without the need for repeat surgery.

Five out of 141 participants analysed were surgical failures, one of which was due to the complication of detachment of the gold chain during surgery. One study reported complications after surgery and found one participant in the closed group had a post-operative infection requiring antibiotics and another participant in the closed group experienced pain during alignment of the canine as the gold chain penetrated through the gum tissue of the palate.

The results from studies for any other outcomes could not be combined, but individual studies did not show evidence of a difference between the two techniques for pain, discomfort, appearance, gum health, length of treatment time or cost (low to very low quality evidence).

How good was the evidence?

Overall, we assessed the quality of the evidence as low, which means we cannot be certain of the findings.

What are the implications for dentists and the general public?

It does not seem that one surgical technique is better than the other for moving displaced eye teeth into the correct position, or for other outcomes, but this finding is uncertain because the quality of the evidence is low.

What should researchers look at in the future?

There is a need for more high-quality studies. Three studies are currently in process. When they are completed, we will include them in an update of this review and may be able to reach firmer conclusions.

Link

Parkin N, Benson PE, Thind B, Shah A, Khalil I, Ghafoor S. Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth. Cochrane Database of Systematic Reviews 2017, Issue 8. Art. No.: CD006966. DOI: 10.1002/14651858.CD006966.pub3.