## 7 Discussion
We identified eight studies that investigated surgical treatment. In the study by [PERSON] [25], the use of CBCT for long-term follow-up after surgical endodontics resulted in an increased diagnosis of persisting or recurrent apical periodontitis, which frequently led to the proposal of more invasive treatment procedures. [PERSON] et al. [4] and [PERSON] et al. [28] showed that CBCT analysis enabled a more accurate appraisal of periapical lesions and healing of endodontic microsurgery than periapical X-ray. However, in another three studies, both CBCT and periapical radiographs produced similar assessments of healing after periapical surgery [14; 15; 36]. In addition, a surgical study combined with the histological gold standard stated that not all lesions detected by CBCT represented periapical inflammatory lesions [29]. Regarding treatment outcome, preoperative CBCT examination was reported to positively contribute to treatment outcomes. Five out of six studies investigating diagnostic thinking or decision making reported that CBCT had a considerable influence on diagnostic thinking and decision making [27; 31; 32; 37; 38]. However, the remaining study concluded that the information obtained from CBCT influenced the radiological findings and the final diagnosis in only a minority of cases, and there was no strong evidence that CBCT increased the observers' certainty or was helpful in making a diagnosis [23]. Regarding the tooth group, 3 studies investigated anterior teeth, 3 studies investigated posterior teeth, and 10 studies investigated both anterior and posterior teeth. CBCT was reported to have a minor effect on the diagnosis of anterior teeth [14; 28; 36] but was reported to assist during the treatment of posterior teeth, where it changed the treatment outcome [24; 30; 33]. In 9 of the 10 studies in which both anterior and posterior teeth were evaluated, the authors reported that the CBCT evaluation modified the diagnosis or treatment plan [4; 22; 25; 27; 31; 32; 35; 37; 38], but in the last study, there was no influence on the treatment plan [15]. In addition, in two of the studies, CBCT had a questionable effect on the diagnosis [26; 34]. Even when a literature search identifies studies claiming to justify the use of CBCT for a specific endodontic indication, it is important to assess whether these studies are of acceptable methodological quality [20]. Methodological quality assessments should be based on a structured process of analyzing the risk of bias in the study This can be achieved by considering a set of quality items, such as checking whether the variety of patients is representative of the patients who will receive the test in practice and whether a valid reference standard was used to determine the presence or absence of the target condition (disease status) [20]. The results of these specific quality assessments can be used to determine the level of risk of bias of a study [20]. In the current study, the majority of the identified articles (n = 20, 90%) had a high risk of bias, and only two articles were identified as having a low risk of bias. The results of our analysis indicate that the available endodontic literature assessing the effects of CBCT on diagnostic thinking, decision making, and treatment outcomes is limited, and the reliability of these studies is jeopardized by potential systematic errors or deviations from the truth, either in the results or in the inferences [20]. Well-designed studies are essential to inform endodontists and clinicians regarding diagnostic thinking, decision making, and treatment outcome assessment with CBCT imaging. Further in vivo research is essential and should be conducted in comparison to gold-standard techniques. The main problem is the difficulty in conducting comparative in vivo clinical research both in terms of diagnosis and outcome assessment due to ethical, practical, and clinical concerns.