## 5 Conclusions  
In conclusion, orthodontic therapy, while highly effective in achieving desired tooth movements, is associated with the potential side effect of apical root resorption (ARR). This permanent loss of hard tissue at the root apex can range in severity, with severe cases compromising the crown-to-root ratio and, in extreme instances, leading to tooth loss. The incidence of ARR in orthodontic patients varies widely, and its impact on patients' quality of life and treatment outcomes underscores the need for a comprehensive understanding and effective management of ARR. Clear aligners have gained popularity as an alternative to conventional fixed appliances for orthodontic treatment. The mechanism of tooth movement during clear aligner therapy and its association with ARR remain areas of ongoing research and debate. The nature of forces exerted, whether intermittent forces from aligners, or continuous forces from fixed appliances, may influence the occurrence and severity of root resorption. Studiescomparing ARR in patients treated with clear aligners versus fixed appliances have yielded varying results, indicating the complexity of this phenomenon. The assessment of ARR is crucial for accurate diagnosis and treatment planning. Traditional two-dimensional radiography has limitations in capturing the three-dimensional topographical changes associated with root resorption. Cone beam computed tomography (CBCT) emerges as a valuable tool, offering higher accuracy in the diagnosis and quantification of ARR. Recent studies utilizing CBCT have provided insights into the prevalence and severity of ARR in patients undergoing orthodontic treatment with clear aligners or fixed appliances. Comparative studies, such as the one conducted by [PERSON] et al., revealed differences in the prevalence and severity of root resorption between clear aligner and fixed appliance groups. The choice of treatment modality and its impact on ARR may vary depending on tooth type and other factors. Additionally, investigations into the dimensions of alveolar bone alterations and orthodontically induced inflammatory root resorption (OIIRR) further contribute to our understanding of the consequences of orthodontic tooth movement. Recent research, such as the retrospective study by [PERSON] et al., highlights the importance of considering post-treatment alveolar bone alterations and root resorption when comparing different orthodontic approaches. Comparing clear aligners with fixed orthodontic appliances, the study demonstrated distinct effects on alveolar bone thickness, height, and root length, emphasizing the need for careful evaluation in treatment planning. In summary, while ARR remains a concern in orthodontic therapy, ongoing research, particularly with the use of advanced imaging techniques like CBCT, contributes to a better understanding of the factors influencing root resorption. Clinicians should weigh the risks and benefits of different treatment modalities, considering individual patient characteristics and the potential impact on root health. As orthodontic techniques continue to evolve, addressing and minimizing the risk of ARR will be crucial for optimizing treatment outcomes and ensuring long-term oral health for patients undergoing orthodontic therapy. The variability in treatment protocols, patient populations, and orthodontic techniques across different regions and practices may limit the generalizability of the results and should be considered in future research endeavors. Conceptualization, A.D.I., F.I., D.D.V. and G.D.; methodology, A.D.I., A.M.I. and G.G. ; software, C.D.P. and G.D.; validation, E.d.R. and G.P. ; formal analysis, A.M.I., A.P. and G.M. ; investigation, A.D.I. ; resources, A.M., A.M.I. and F.I. ; data curation, G.D., D.D.V. and G.G. ; writing--original draft preparation, A.D.I., A.M.I., G.D. and F.I. ; writing--review and editing, F.I., G.P., G.G., G.M. and C.D.P. ; visualization, E.d.R., A.P., A.M. and G.M. ; supervision, D.D.V., F.I., A.M. and A.D.I. ; project administration, F.I.