This study was evaluated anxiety, pain, and oral health-related quality of life in individuals treated with conventional fixed appliances (Group A) and clear aligners (Group B) for moderate malocclusion during the initial phase of orthodontic treatment

Clear aligner treatment is becoming increasingly popular among orthodontic treatment option. With this treatment method, which was introduced the literature at the beginning of the 20th century, approximately four million individuals in 2019 and over twelve million individuals have already been treated today. In addition, the number of commercial companies worldwide producing transparent plaque has reached twenty-seven, indicating that these figures will increase rapidly. Although there are debates about the effectiveness of the treatment, the increase in living standards and the improvement of the quality of life of individuals relative to conventional fixed orthodontic treatment have increased interest in clear aligner treatment.

The World Health Organization has multidimensional definitions of the concepts of "quality of life" and "health," and their common point is that they emphasize the importance of the psychological and social status of individuals in recent years. Quality of life is affected by dentofacial problems caused by malocclusions, as well as the psychosocial state of individuals during orthodontic treatment. Oral health-related quality of life was defined as "the absence of physical and psychological problems in terms of oral health and self-confidence associated with the maxillofacial region," and the importance of self-confidence and psychosocial status that could affect quality of life was emphasized. The presence of pain and anxiety before and at the beginning of orthodontic treatment are among the factors affecting oral health-related quality of life.

Pain is an emotional state frequently encountered by individuals undergoing orthodontic treatment, leading to cooperation problems and even causing them to give up treatment. In studies comparing the pain levels of individuals treated with conventional fixed orthodontic appliances and clear aligners, individuals treated with clear aligners felt less pain in the first few days, but there was no significant difference in pain levels in later periods of treatment.

The importance of malocclusion type and arc length disperancy has been emphasized in studies comparing conventional fixed therapy and clear plating therapy in terms of pain and quality of life. Considering that the concepts of anxiety, pain, and quality of life are interrelated by each other, there are limited studies in which both treatment methods are evaluated in terms of these factors in a particular malocclusion. The current study aims to compare anxiety and pain values observed in the initial phase of orthodontic treatment and oral health-related quality of life among individuals with moderate malocclusion treated with conventional fixed orthodontic appliances and clear aligners. Our null hypothesis (H0) is that there is no difference in anxiety, pain, or oral health-related quality of life between individuals treated with conventional fixed orthodontic appliances and clear aligners.

Inclusion Criteria:

• Individuals who had not received orthodontic treatment before,
• Angle class I malocclusion,
• 4-6 mm arc length disperancy in both dental arches,
• Permanent dentition period,
• Missing or impacted teeth,
• No smoker,
• No alcohol drinker.

Exclusion Criteria:

• Individuals who underwent extraction fixed orthodontic treatment,
• Radiologically observed alveolar bone loss,
• Missing or impacted teeth,
• systemic disease,
• Using of drugs or analgesics.