The present study aimed to investigate the prevalence of MIH in Syrian children and its clinical characteristics. A cross-sectional study design was employed and a sample of 1138 children was recruited from different regions in Damascus, Syria. The study found a high prevalence of MIH in Syrian children, with a rate of 39.9%.
In this study, the European Academy of Paediatric Dentistry (EAPD) criteria were utilized to diagnose MIH and index teeth were scored using the MIH/HPSMs short charting form by Ghanim et al. (2015) 14. This form was recommended by the recent EAPD policy document about the best clinical practice guidance for dealing with children presenting with MIH 16.
The EAPD criteria are based on clinical observations and take into account the presence of hypomineralized white or brown opacities on the incisal or occlusal surfaces of permanent molars and/or incisors, which are the main clinical features of MIH. The criteria also exclude other possible causes of developmental defects, such as cavitation of the affected tooth surfaces, history of systemic disease, previous treatment, and excessive fluoride exposure 16.
In addition, the EAPD criteria provide a grading system for the severity of MIH, which can be used to classify affected teeth as mild or severe. This allows for a more accurate and consistent assessment of the condition and better comparison between studies16,17. Using the EAPD criteria in this study allowed us to perform consistent and accurate assessment and to provide number about the prevalence of MIH in the sample of children aged 8 to 11 years.
This age range is associated with the eruption of permanent first molars and incisors, which are most affected teeth by MIH, and thus provided us with a more accurate estimate of the prevalence of MIH 16,17. In addition, children in this age group are more cooperative and amenable to a dental examination, which facilitated the data collection process. It’s worth mentioning that this age group was selected as it represents the age group that is most susceptible to suffering from MIH, as the majority of MIH cases are seen in permanent teeth 18.
In this study, the prevalence of MIH in Syrian children aged between 8–11 years from Damascus city was 39.9%, with no significant gender predilection.
It is evident that the prevalence of MIH in Syrian children is higher than in other countries in the region. A study conducted in Jordan reported a prevalence of 13.2% 19, another study in Saudi Arabia reported a prevalence of 15.2% 20. While a study in Lebanon reported a prevalence of 26.7% 21.
Comparing the results of this study to studies conducted in underdeveloped countries with similar socio-economic conditions to Syria can provide valuable insights into the factors that may contribute to the high prevalence of MIH in Syrian children.
A study conducted in India, for example, reported a prevalence of MIH of around 7.6% 22, which is significantly lower than the rate found in this study. Similarly, a study conducted in Sudan reported a prevalence of MIH of around 20.1% 23.
These findings suggest that the prevalence of MIH in Syrian children may be unique to the country, possibly due to the effects of the ongoing Syrian crisis on the population’s oral health. The crisis may have resulted in a lack of access to oral healthcare services, as well as poor living conditions that may have affected the oral health of children in Syria 24,25.
The Syrian crisis could potentially affect the prevalence of MIH in Syrian children. The crisis has led to significant disruptions in the healthcare system and access to medical care in Syria, which could potentially affect the incidence and diagnosis of MIH. Additionally, the crisis has led to a displacement of a large number of Syrian people, which could lead to changes in children’s living conditions, diet, and access to clean water, which are all potential risk factors for MIH 26–28. Children who were displaced may have less access to regular dental check-ups or preventive measures for oral health, which could increase the risk of MIH. Moreover, factors such as stress, malnutrition, and exposure to environmental toxins, which are all associated with the Syrian crisis, could also affect the development of children’s teeth and lead to an increased incidence of MIH 29.
It is important to consider the impact of the Syrian crisis on oral health and potential changes in the prevalence of MIH in Syrian children when undertaking research on the disorder in this population.
The results of this study showed that there was no significant difference between Syrian male and female children in the prevalence of MIH which was consistent with other studies that showed that MIH can effect both genders without predilection. 19–21,23
This finding suggests that MIH is not gender-specific, and both boys and girls are equally likely to develop this condition 30. This information is valuable in understanding the impact of MIH on paediatric dental health and in providing equitable care for all children. The lack of a gender-based difference in MIH prevalence also highlights the importance of considering other risk factors, such as environmental exposure, nutritional deficiencies, and medical conditions, when assessing the cause and development of MIH.
In this study, it was observed that 36% of children diagnosed with MIH had only their permanent molars affected, while the rest had both molars and incisors involved. This finding highlights the variable presentation of MIH in children and its potential impact on both anterior and posterior teeth. This result also indicates the need for a comprehensive examination of all teeth in children with suspected MIH, rather than just focusing on a single affected tooth or area 31. This information can be valuable for dental practitioners to better understand the pattern of MIH in children and provide comprehensive and effective care for these children.
The findings of this study suggested a strong correlation between the number of molars affected MIH and the number of affected PIs and HPSMs which was consistent with the finding of other studies 20,23,32. This outcome highlights the systemic nature of MIH and its potential to have a significant impact on a child’s oral health. The higher the number of molars affected, the greater the likelihood that other teeth in the oral cavity will also be affected by MIH.
This information is crucial for dental professionals as it highlights the need for early detection and intervention to prevent the negative effects of MIH and protect the oral health of children. Further studies are still required to further understand the underlying mechanisms behind this correlation in order to develop effective preventive and management strategies for MIH.
Regarding the severity of MIH lesions, the results of this study showed that the severity of MIH was higher in molars compared to incisors. This finding is consistent with previous studies, which indicated that MIH is more frequent and severe in molars than incisors 32,33.
In fact, molars are subject to more occlusal stress during chewing and grinding, which could increase the risk of hypomineralization. Additionally, molars have longer developmental periods and more complex morphologies compared to incisors, making them more susceptible to MIH 18. The higher severity of MIH in molars is a cause for concern as molars play a crucial role in biting and chewing, and their loss or damage can have a significant impact on oral function and quality of life. Thus, it is important to develop strategies to prevent or manage MIH in molars.
In addition, the results of the current study suggested that there is a significant difference in the severity of MIH between female and male children. Specifically, the findings showed that the severity of MIH is higher in girls compared to boys. This difference could be attributed to the faster rate of tooth eruption in girls 20,34. Previous research has demonstrated that the earlier eruption of teeth can increase the susceptibility to hypomineralization due to the longer exposure to risk factors 30.
As a result, it is important for dental professionals to be aware of the higher MIH severity in girls in the Syrian population and to consider this factor when developing preventive and therapeutic strategies. Further studies are still essential to explore the underlying mechanisms that contribute to the gender differences in MIH severity.
Moreover, this study indicated that the most common clinical pattern of MIH in Syrian children was demarcated opacities. This pattern is characterized by a white or yellowish discoloration, chalky appearance, and/or rough surface on the affected teeth. The prevalence of this pattern is consistent with previous studies conducted on MIH in children from different countries 19,21,23, indicating that demarcated opacities are a common feature of MIH lesions in paediatric populations globally. The observed pattern highlights the need for early detection and management of MIH in Syrian children, as the severity and extent of the lesions can significantly impact the oral health and quality of life of affected individuals 10.
One of the key findings of this study was that children with MIH tended to have a higher DMFT (Decayed, Missing, and Filled Teeth) index compared to those without MIH. This highlights the negative impact that MIH can have on oral health and raises important questions about the underlying causes of this disparity. The presence of mild enamel lesions in MIH-affected molars may make children more susceptible to dental decay, as the softer and more porous enamel may be more prone to caries formation 8,35. Additionally, children with MIH may experience more discomfort or pain associated with their teeth, which could impact their oral hygiene habits and increase the likelihood of developing dental problems 36. Further work should explore these potential explanations and develop effective strategies for preventing MIH in children.
It is important to note that this study has some limitations, as it does not allow causal inferences to be drawn and did not assess the quality of oral health care, socio-economic status, or other environmental factors that could be associated with MIH. Therefore, future work should consider exploration of the potential factors that contribute to high prevalence of MIH in Syrian children during the Syrian crisis.