Dentoalveolar surgery
Evaluation of Risk Factors for External Root Resorption and Dental Caries of Second Molars Associated With Impacted Third Molars

https://doi.org/10.1016/j.joms.2020.04.041Get rights and content

Purpose

Impacted third molars (M3s) may lead to external root resorption (ERR) and dental caries (DC) in the adjacent second molars (M2s). The aim of this study was to identify the risk factors for ERR and DC in M2s associated with impacted M3s.

Materials and Methods

We implemented a cross-sectional study and enrolled a sample composed of patients with M3s and M2s present and cone-beam computed tomography (CBCT) scans available for review. If there was contact between the M2 and the adjacent M3 and the border of radiolucency was more distinct, the case was considered ERR. Apart from that, the case was considered DC. Potential predictor variables were defined as age, gender, tooth location, M2-M3 contact, root development in M3, M3 inclination, M3 impaction type, and M3 follicular diameter. Outcomes of the study were DC and ERR in M2s. CBCT was used to detect the presence of DC and ERR in M2s.

Results

A total of 250 eligible images of M3s in the upper and lower jaws of 167 patients were included. The mean age of the patients with CBCT images available was 26.08 ± 4 years (range, 18 to 40), and 43.6% of the patients were men. Factors associated with a significantly increased frequency of ERR in M2s included maxillary location, presence of M2-M3 contact, and mesioangular inclination (P < .005). DC in M2s was significantly more likely to occur in those with absence of contact between M2 and M3 (P < .005).

Conclusions

The results of this study showed an increased risk of ERR to be associated with maxillary molars, mesioangular inclination, and presence of M2-M3 contact. The variable associated with an increased risk of DC was the absence of M2-M3 contact.

Section snippets

Study Design

This cross-sectional study was conducted at the Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Van Yüzüncü Yıl University, Van, Turkey, between 2011 and 2019. The study protocol was approved by the university ethics committee (No. 2019/10-06). The study was conducted in accordance with the institutional and national ethical standards of the responsible committee on human experimentation and with the principles of the Declaration of Helsinki.

Study Sample

This study included patients

Results

Of 680 CBCT images retrieved from the digital database, 513 failed to meet the inclusion criteria; a total of 250 eligible images of M3s in the upper and lower jaws of 167 patients were included. The mean age of the patients with CBCT images available was 26.08 ± 4 years (range, 18 to 40 years).

The relation between ERR and age, gender, tooth location, root development in M3, M3 inclination, M3 impaction type, M3 follicular diameter, and presence of M2-M3 contact is presented in Table 1.

Discussion

In this study, we investigated the risk factors for ERR and DC of the upper and lower M2s in relation to the position of the M3s. According to the null hypothesis of the study, the risk factors for ERR and DC in M2s were considered patient age, gender, tooth location, development of M3 roots, inclination of M3, type of M3 impaction, size of M3 follicle, and M2-M3 contact, and there was no variation among these risk factors. Factors associated with a significantly increased frequency of ERR in

Acknowledgments

The authors thank Dr Sıddık Keskin for his assistance with the statistical analysis.

References (33)

Cited by (9)

  • Is it necessary to remove bone-impacted teeth? A retrospective study

    2023, Journal of Stomatology, Oral and Maxillofacial Surgery
    Citation Excerpt :

    Simultaneously, in our research, we discovered a phenomenon: when M3 crown develops directly against M2 root tip, M2 root absorption is most likely, and M2 should be removed before ERR. The incidence of root resorption in the second molar was 34.72% in cases where the third molar was complete bone impact, which was essentially consistent with the incidence of 33.6%∼50% obtained by other researchers [10,17,18]. According to the study, we were able to solve a few of the problems we raised.

  • Prognosis of Second Molars with External Root Resorption Caused by Adjacent Embedded Third Molars

    2022, Journal of Endodontics
    Citation Excerpt :

    Our results support the possibility of the aseptic pulp in ERR-M2s remaining vital without further intervention after EM3 extraction, indicating a novel option for teeth with ERR caused by adjacent embedded tooth. ERR in second molars is a pathological process mainly caused by mechanical pressure from EM3s15,27 and can therefore be arrested after EM3 extraction16,26. Once resorption has ceased, osteoclasts and osteoblasts move to the root surface, enabling healing of the cementum and bone28.

  • Orthodontic traction of an impacted maxillary third molar through a miniscrew-anchored cantilever spring to substitute the adjacent second molar with severe root resorption

    2022, Journal of the American Dental Association
    Citation Excerpt :

    The whole procedure is illustrated in Figure 7. Impacted third molars are reported to be associated with pathologic changes such as caries and root resorption,12 justifying the need for prophylactic extraction of impacted third molars that pose high risks of pathologic changes to adjacent second molars.13 In particular, root resorption of second molars caused by impacted third molars is encountered often in clinical practice.14

  • Removal or retention of nonimpacted third molars

    2023, Chinese Journal of Stomatology
View all citing articles on Scopus

Conflict of Interest Disclosures: None of the authors have any relevant financial relationship(s) with a commercial interest.

View full text