When teeth fail to erupt properly
In some children, approximately 2–3%, the upper canine teeth do not erupt as they should. Instead of emerging into the mouth, they remain trapped inside the jawbone, often on the palate side. This can damage the roots of neighboring teeth and must be treated with a combination of surgery and orthodontics.
“This is not just an orthodontic issue. It’s a serious medical condition,” explains orthodontic specialist and researcher Lucete Fernandes F?r?vig at the Faculty of Dentistry, University of Oslo. She is the first author of this extensive study.
“The treatment begins with surgical exposure of the impacted tooth, followed by orthodontics to guide the tooth into the proper position in the dental arch,” explains Lucete F?r?vig. But there are two common methods – open and closed surgical technique – and until now, there has been a lack of clear evidence on which method yields the best patient outcomes. Several aspects of the entire treatment are under investigation. The article focuses solely on the first part of the treatment: the surgical exposure.
The study
To determine which method produced better outcomes, Lucete F?r?vig and a research team from Norway and Sweden conducted a randomized controlled clinical trial (RCT) – the most reliable form of medical research.
“This type of study sits at the top of the evidence pyramid. We compare two randomized groups under strictly controlled conditions to ensure the differences are due to the treatment itself, not random chance,” explains Lucete F?r?vig.
100 children aged 10 to 16 were included in the study and randomly assigned to either the open or closed technique. After surgery, they completed questionnaires about pain, discomfort, and use of pain medication. The surgeons also measured procedure time and recorded any complications.
What’s the difference between the two techniques?
Open technique: The surgeon removes gum and bone, allowing the tooth to erupt naturally. Orthodontic treatment begins once the tooth emerges from the jaw.
Closed technique: The tooth is exposed, and a small chain is attached to the tooth before the gum is sutured back into place. Tooth movement begins earlier, often within two weeks, using braces.
The open technique caused more pain and discomfort
“It was clear that patients who underwent the open technique reported more pain—both during the procedure and in the following days, says F?r?vig. “Many described the drilling and the wound area as the most uncomfortable aspects.”
The first three days after surgery stood out in particular, with some patients experiencing pain for over a week.
The open technique was faster
“The open technique was quicker to perform, especially when a flap surgery was not performed. This piece of information can make a difference in busy clinics under time pressure,” F?r?vig says.
On average, the procedure took several minutes less than the closed technique, which requires opening, chain attachment, and suturing.
Closed technique required more painkillers after suture removal
“It was surprising that the closed group used more painkillers – but not immediately after the surgery,” she says.
“This occurred after removal of the sutures and surgical dressing.” A surgical dressing is a protective material placed over a wound in the mouth after dental surgery to promote healing and protect the area from irritation and infection.
She explains this is likely due to the chain under the gum, which can delay healing in the area over time, causing more discomfort when sutures are removed and the tissue is still tender.
More complications with the open technique
“Complications were fortunately rare, but they occurred more often in the open group,” says Lucete F?r?vig.
“We saw more cases of bleeding and loss of surgical dressing.”
For instance, eight patients in the open group reported bleeding, compared to none in the closed group. Additionally, more patients lost the dressing that is supposed to cover the exposed area.
Clear answers to give
“Now we have a research-based answer,” she says.
“Previously, we had to tell patients: both methods work.”
“Now we can say more: The open surgical method takes less time but often causes more pain, discomfort, and higher risk of bleeding. The closed method takes a bit longer but is experienced as more comfortable. This gives patients a real choice, based on knowledge, not guesswork.”
She adds that both techniques still have their place and that the most important thing is personalising the treatment to each patient.
Gaining international attention
The study was recently featured in Kevin O’Brien’s Orthodontic Blog, one of the most influential voices in orthodontics globally. The blog, written by Professor Emeritus at the University of Manchester, highlights high-quality research and warns against poor or exaggerated findings.
Kevin O’Brien wrote:
“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 (…) We need more studies like this.”
“It was incredibly gratifying to see the study being appraised by Kevin O’Brien. He is known for being critical and honest, so this was a vote of confidence,” says Lucete F?r?vig.
Research with immediate impact
The study is already published and being used in clinics. It’s an example of research that doesn’t stay locked in a drawer but directly improves patient care.
“This is research that matters,” says F?r?vig. “We meet patients every day who have questions. Now we have answers based on evidence.”
“When treatment choices have direct consequences for the patient’s experience of pain and safety, we need studies like this. And it’s inspiring to see the Department of Orthodontics taking a leading role in driving this type of clinical research forward,” concludes Dean Hans Jacob R?nold at the Faculty of Dentistry.