A great study on patients’ perceptions of open v closed exposure for unerupted canines?
Patient-centred research is becoming increasingly important. This new study examines patients’ perceptions of two competing treatments for exposing palatally positioned canines.
Orthodontic research is hopefully shifting its focus from the treatment outcomes of orthodontists to the outcomes experienced by patients. One of the most significant aspects of this shift is the patients’ perception of pain and discomfort, which is particularly important when considering the effects of surgery.
When we need to expose an unerupted canine that is positioned palatally, we can opt for either open or closed surgical procedures. Both methods have similar success rates; however, we know very little about patients’ preferences regarding these treatments. This topic was the focus of an interesting new randomized trial.
A team from Norway, Sweden and Switzerland did this study. The AJO-DDO published the paper. This is an open-access paper, so anyone can read it.
Lucete Faerovig et al.
Am J Orthod Dentofacial Orthop 2025;167:382-98. https://doi.org/10.1016/j.ajodo.2024.11.014
What did they ask?
They did this study to ask
“What are the patient perceptions of recovery, duration of procedure and complications of closed or open exposure of palatally displaced canines”?
What did they do?
The team did a 2 centre RCT with 2 parallel groups and a 1:1 allocation ratio.
The PICO was
Participants
Orthodontic patients from 2 centres with unilateral or bilateral palatally displaced canines, aged under 16 years with canine tips in sectors II-IV on panoramic radiographs.
Intervention
Closed exposure of canine
Comparison
Open exposure of canine
Outcomes.
Patient reported experiencing pain and discomfort, as well as analgesic intake and complications observed over the three weeks following surgery. Data were collected through questionnaires that included pain documentation using visual analogue scores and open and closed questions.
They collected data 10-15 days after surgery and then 1-2 weeks later.
They carried out a clear sample size calculation based on a 15 mm difference in pain perception on the VAS scores. This indicated that they needed to include 100 participants randomised into two groups.
An orthodontist recruited the participants. They used a pre-prepared block randomisation. An independent person not involved with the trial concealed allocations in each centre.
It was not possible to blind the operator. However, data was analysed blind.
What did they find?
They enrolled 100 participants in the study. Eight were excluded for various reasons, such as moving away from the area. Consequently, 92 completed the trial with a mean age of 13 years. Fifty-nine were female, and thirty-three were male. There were 47 canines in the closed group and 45 in the open group. No pre-treatment differences existed between the two groups.
87 participants returned the first questionnaire, and 75 participants returned the second, for a response rate of 94% and 81%, respectively.
The main findings were:
- The pain response scores were highly variable. The open-group participants recorded higher levels of pain and discomfort.
- There was no difference in analgesic consumption between the groups.
- The operative time was shorter for the open group with no flap replacement.
- When they looked at complications, 5/47 of the closed and 12/45 of the open groups had a complication. Importantly, bleeding was the most common complication in the open exposure group (8 patients).
The overall conclusions were
“Participants in the open group experienced more pain and discomfort than those in the closed group. However, complications were sparse and more common with the open technique”.
What did I think?
This was a well-conducted and ambitious randomized trial involving numerous participants, which must have required significant effort. Notably, the team reported relevant outcomes to our patients, and I would like to congratulate them on their study. I have no criticisms of their methods.
The results are both interesting and clinically significant. We can use this information when discussing treatment options with patients. It lets us inform them that the open technique may result in more pain. There is also a higher risk of minor postoperative complications, such as bleeding. Therefore, this study is highly useful.
We need more studies of this nature.
Emeritus Professor of Orthodontics, University of Manchester, UK.
Dear Kevin,
This is indeed a useful and well-conducted study. The findings and the conclusions in the study noted that the open-group participants recorded higher levels of pain and discomfort. Unfortunately, your reported wrongly
credited the open technique with illiciting a lesser degree of pain. This is in addition to the open technique being the more prone to post-surgical complications. Perhaps this could tip the choice for technique preference in the opposite direction. The investigation underlines the continued need for further study in this area.
With best wishes,
Adrian Becker
Hi Adrian, thanks for the comments. I have now corrected my typo and I am sorry that I was careless in this post. I think that I must have been distracted when I wrote the post by the unusually sunny UK weather! Best wishes: Kevin
I think a interesting follow up study will be the longer term evaluation of pain and discomfort during the activation phase of erupting the teeth comparing the two techniques.
Did both groups have orthodontic hardware in the post-surgical timeframe? In the pre-surgical timeframe? For whatever reason it is not obvious in my reading of the AJO article.
thanks
Regarding the open exposure technique: it would be interesting to know if using an upper removable appliance to hold the Coe-pak in place for a period of time, rather than suturing the Coe-pak in place, reduces the level of post-operative pain and bleeding.