Beta thalassemia is a genetic disorder affecting hemoglobin synthesis. ¹ The major form expresses many characteristics, including the “chipmunk” face. ² It is the side effect of extreme maxillary protrusion, due to the increased volume of hematopoietic bone marrow. ³ The observed maxillary enlargement can cause structural changes in the oral cavity such as teeth protrusion, spacing, occlusal deep bite, open bite, and different degrees of malocclusion that predispose patients to dental problems. ⁴ , ⁵ Many thalassemia major (TM) patients suffer from severe Angle class II malocclusion that may affect the patient's life quality. ⁶ , ⁷ , ⁸

Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) has been developed to objectively assess the impact of malocclusion on oral health. ⁹ , ¹⁰ It has been shown that the majority of TM patients have class II skeletal and dental malocclusion with increased overjet and severe tooth displacements compared to controls, and has consequently been graded to have a high need for orthodontic treatment. ¹¹

Oral Health-related Quality of Life (OHRQoL) is one's satisfaction regarding his/her functional, emotional, and esthetic oral expectations. ¹² The OHRQoL questionnaires measure self-perceived oral need, which is an essential aid to plan suitable dental treatment for each individual. ¹³ Several studies have measured OHRQoL in TM patients. Amirabadi et al. found lower OHRQoL in TM patients than controls; ¹⁴ Phrai-In et al. reported a high prevalence of oral impacts on TM patients' daily performances; ¹⁵ and Ebeid et al. reported a negative impact of TM on emotional well-being. ¹⁶ On the other hand, Fadel et al. reported an acceptable OHRQoL in TM. ¹⁷

Oral Health Impact Profile-14 (OHIP-14) is one of the most utilized questionnaires in assessing OHRQoL, with proven validity and reliability. ¹⁸ Some studies have used this means to assess OHRQoL in systemic diseases, including TM. Mohamadi et al. found a negative impact of poor oral health status on OHIP-14 score in TM, ¹⁹ and Motallebnejad et al. reported that oral health affects OHIP-14 in TM patients, especially regarding its psychological aspects. ²⁰

Of note, Liu et al. found that orthodontic treatment need is associated with OHRQoL, ²¹ and Dalaei et al. reported a negative impact of malocclusion on OHRQoL in the general population. ²² However, since the occlusal problems in TM patients may significantly affect OHRQoL as well, ²³ the aim of the present study was to evaluate the relationship between orthodontic treatment need and OHRQoL in TM patients living in Isfahan, Iran.

Patients and sampling

This was an analytic cross-sectional study approve in research and ethics committee of Isfahan (NO:399551). The participants were recruited from patients with TM referred to Oral Medicine Department, Faculty of Dentistry, Isfahan University of Medical Sciences, from June 2019 to June 2020.

The patients with a confirmed diagnosis of TM between 18 and 35 years of age were included in this study. The exclusion criteria were suffering from other systemic diseases, current drug consumption, need for hospitalization or blood transfusion, wearing complete or partial dentures, history of or current orthodontic treatment, and not willing to participate in this study. The study design was explained to all present patients, and a total of 105 volunteers took part.

Oral health-related quality of life

Data were collected using self-administered OHIP-14 questionnaire Figure 1. Reliability and validity of the Persian version of the questionnaire have been previously confirmed. ¹⁸ Age and gender of patients were asked as demographic data and attached to their questionnaire. The OHIP-14 questionnaire consists of 14 questions which are rated on a 5-point scale, ranging from “never” (score 0) to “always” (score 4). The total score is therefore going to be from 0 to 56. A lower score indicates a better OHRQoL and vice versa. The score for each domain of the questionnaire was calculated as well, a score from 0 to 8 for each of the 7 domains. Figure 1

The Oral Health Impact Profile-14 questionnaire.

One hundred and five TM patients participated in the present study. Fifty-five (52%) were women, and 50 (48%) were men. The mean (±standard deviation [SD]) age was 24.92 (±9.33). Definitive orthodontic treatment need frequency was 27.6%. The mean scores of OHIP-14 and orthodontic treatment need frequency for both genders are shown in Table 1. T-test showed that women had higher OHIP-14 scores (poorer OHRQoL) than men (P = 0.015). Chi-square test revealed no statistically significant difference in orthodontic treatment need frequency between men and women (P = 0.15).{Table 1}

Pearson correlation test showed that OHRQoL deteriorates as patients age (P < 0.001, r = 0.70). Also, t-test revealed that older patients experience more orthodontic treatment needs (P < 0.001). Table 2shows the mean score of OHIP-14 in relation to orthodontic treatment needs. T-test showed better OHRQoL in patients with no need (P < 0.001). The mean (± SD) scores of OHIP 14 domains are shown in Table 3, as well as the relationship between each domain and gender, age, and orthodontic treatment need.{Table 2}{Table 3}

Occlusion morbidities are of great concern in TM patients. An excessive amount of hematopoietic bone marrow expands facial bones in these patients, due to extremely increased demand for hematopoiesis ² , ³ and maxillary protrusion ensues, which may cause difficulty in oral function and esthetics, leading to OHRQoL impaction. ¹⁶

The prevalence of malocclusion among TM patients was 27.6% in the present study. In a systematic review ²⁴ by Eslamipour et al., it was reported that in the Iranian population, 23.8% of people had all types of malocclusion discovered by IOTN-DHC. Hedayati et al. reported a definitive need for orthodontic treatment in 18.39% of their Persian study population, ²⁵ and the mean IOTN-DHC was 1.23 (±2.45) in the Persian participants of Naseri et al. study. ²⁶ Therefore, the prevalence of malocclusion among TM patients was slightly higher than the general population based on the present study, which is in consensus with the results of previous studies. ¹¹ , ²⁷

The impact of malocclusion on OHRQoL of the general population has been well shown in the previous studies. ²¹ , ²² , ²⁸ Similar to our results, Dalaie et al. found a significant correlation between orthodontic treatment need and the total OHIP-14 score among the general population. No significant relationship between physical disability and orthodontic treatment need was found in their study, in accordance with the results of the present study. ²² This may reflect the fact that, even in TM patients, esthetic and speech considerations, rather than food intake problems, have a substantial impact on OHRQoL. ²⁹ Furthermore, Sun et al. reported that functional limitation and social well-being domains of OHRQoL are more easily affected by malocclusion than other domains, ³⁰ which is in agreement with our results.

Studies measuring OHRQoL in TM patients have bolded the impact of oral health status on psychological aspects of OHRQoL. Ebeid et al. reported a negative impact of TM on the emotional well-being aspect of OHRQoL. ¹⁶ In the study by Motallebnejad et al., psychological aspects of OHIP-14 were more impacted by oral health condition, compared to functional aspects, in Persian TM patients. ²⁰ Therfore, psycho-social support seems mandatory to improve OHRQoL in TM patients.

This study detected lower OHRQoL scores in all domains of OHIP-14 among older people with TM than the younger ones. It sounds that as younger patients have more strictly been under care since their birth, they have developed less medical problems affecting their oral condition, resulting in a better OHRQoL. Furthermore, they might have paid more attention to their oral hygiene, which may have improved their OHRQoL. This fact urges the planning of prompt medical and dental support in TM patients, including primary medical intervention to alleviate facial bone marrow changes as early as possible, as well as orthopedic and functional appliances to prevent or at least reduce orthosurgical needs. ²³

The present study showed a statistically significant relationship between orthodontic treatment need and OHIP-14 score. IOTN-DHC is an objective tool, helping the dentist to meter patient's need for orthodontic treatment. On the other hand, OHIP-14 is quite a subjective means of assessing the impact of oral health on one's daily life. As improving the OHRQoL is considered the final goal for every dental or orthodontic treatment, ³¹ , ³² , ³³ , ³⁴ , ³⁵ the results of the present study facilitate the use of subjective methods, such as IOTN-AC (esthetic component) or several OHRQoL questionnaires, in planning an appropriate orthodontic treatment for TM patients.

Of course, this study was done within the limitations of a cross-sectional research. Studies investigating the cause–effect relationship between variables could interpret the impact of malocclusion on OHRQoL domains more accurately. Besides, several oral health parameters might have influenced OHIP-14 score in the present study, including a number of present teeth or previous dental treatments. Future studies are recommended to further elucidate the exact role and interaction of such factors in determining OHRQoL in patients suffering from TM. Developing disease-specific questionnaires to executively measure OHRQoL in TM would help improving OHRQoL in these patients a great deal.

TM patients with the need for orthodontic treatment experienced worse OHRQoL compared to their counterparts without this need. It seems that more attention has to be paid to treat orthodontic problems in these patients to improve their oral health and quality of life.

Financial support and sponsorship

Nil.

Conflicts of interest

The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or nonfinancial in this article.