When patients feel they have been harmed by orthodontic treatment, what do they usually blame? And when the case is independently reviewed, does that explanation hold up?
A new study from Aarhus University in Denmark examined seven years of compensation claims to determine what patients reported and what the subsequent clinical assessments revealed.
The findings offer an interesting insight into both the types of harm associated with orthodontic care and the gap between what patients perceive as harm and what is ultimately judged to be compensable.
What Did the Researchers Investigate?
Researchers analysed data from the Danish Dental Compensation Association (DDCA), a no-fault scheme where patients can seek compensation for dental or orthodontic harm without having to prove malpractice.
This means they can make a claim for the harm they believe they suffered without first filing a formal complaint against their dentist or orthodontist. A dental expert reviews each claim against accepted professional standards, categorises it, and a legal officer makes the final call.
The researchers pulled 644 orthodontic-related claims filed between June 2017 and August 2024 and looked at what patients said went wrong, what event actually caused the harm, and what harm was recognised.
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What Were the Most Common Types of Orthodontic Harm?
Of the claims reviewed, 196 (30.4%) were accepted as involving patient harm and resulted in compensation.
Active orthodontic treatment accounted for most of these cases (51.5%, n = 101), followed by delayed diagnosis (24.5%, n = 48) and retention-related problems (9.2%, n = 18).
Looking at the types of harm, apical root resorption severe enough to result in tooth loss was the most common (14.8%, n = 29), followed by gingival or soft-tissue injury (13.3%, n = 26), worsening of the occlusion after treatment (9.2%, n = 18), and other problems, including tooth damage caused by delayed diagnosis (8.2%, n = 16).
Assessment, diagnosis, treatment planning and retention are fundamental components of orthodontic care. LDI’s Diploma in Orthodontics & Dentofacial Orthopaedics covers these areas as part of a wider programme focused on evidence-based orthodontic treatment and case management.
What Did Patients Believe Had Gone Wrong?
Patients most often blamed relapse (18.6% of claims) or felt that the treatment simply had not worked (12.6%).
Yet these were among the least likely claims to be upheld.
Relapse was especially unlikely to qualify for compensation, with only 1 of 120 claims accepted.
The findings therefore highlight a clear gap between what patients perceive as harm and what is ultimately judged to be compensable.
What Does This Mean for Clinical Practice?
It is important to recognise that DDCA captures only harms that patients reported and that were subsequently accepted for compensation. Therefore, these 196 cases do not represent the actual rate of adverse events in Danish orthodontics.
Nevertheless, the findings suggest that worsening occlusion may be linked to diagnosis and treatment planning, while some retention-related problems may be preventable through timely follow-up after retainer failure and clearer communication about the need for long-term retention.
The difference between patient perceptions and independently assessed harm is also notable. While relapse was the most commonly cited reason for making a claim, it was rarely accepted for compensation. This reinforces the value of clear communication around expected outcomes, stability and the long-term role of retention throughout the orthodontic treatment journey.
Study Limitation
These findings are specific to Denmark’s healthcare and compensation system, where thresholds for harm may differ from those in other countries.
The data also did not distinguish between general dentists and specialist orthodontists, so differences between provider types cannot be assessed.
Read More
Ferlias N, Grigoroudi A, Woolley J, Nielsen HP, Stoustrup P. Patient Harm From Orthodontic Care (Part I): Types and Frequency of Patient-Reported Harms From a National Database. Orthodontics & Craniofacial Research. 2026;0:1–9.
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