Abstract
Objectives
Distolingual root of the permanent mandibular first molar (PMFM-DLR) has been frequently reported, which may complicate the treatment of periodontitis. This study aimed to assess the morphological features of PMFM-DLR and investigate the correlation between the morphological features of PMFM-DLR and periodontal status in patients with Eastern Chinese ethnic background.
Materials and methods
A total of 836 cone beam computed tomography (CBCT) images with 1497 mandibular first molars were analyzed to observe the prevalence of PMFM-DLR at the patients and tooth levels in Eastern China. Among them, complete periodontal charts were available for 69 Chinese patients with 103 teeth. Correlation and regression analyses were used to evaluate the correlation between the morphological features of DLR, bone loss, and periodontal clinical parameters, including clinical attachment loss (CAL), probing pocket depth (PPD), gingival recession (GR), and furcation involvement (FI).
Results
The patient-level prevalence and tooth-level prevalence of DLR in mandibular first molars were 29.4% and 26.3%, respectively. Multiple linear regression analysis suggested that bone loss at the lingual site and CAL were negatively affected by the angle of separation between distolingual and mesial roots in the transverse section, while they were significantly influenced by age and the angle of separation between distobuccal and mesial roots in the coronal section.
Conclusions
The prevalence of PMFM-DLR in Eastern China was relatively high in our cohort. The morphological features of DLR were correlated with the periodontal status of mandibular first molars. This study provides critical information on the morphological features of DLR for improved diagnosis and treatment options of mandibular molars with DLR.
摘要
下颌第一磨牙远舌根已经被广泛报道,它的存在使牙周炎的治疗更为复杂。本研究旨在评估中国东部地区人群中下颌第一磨牙远舌根的发生率,并探讨远舌根的形态学特征与骨破坏及牙周状况的关联性。本研究通过对中国东部地区836例患者共1497颗下颌第一磨牙的锥形射束电脑断层扫描(CBCT)进行流行病学分析。其中,69例患者的103颗下颌第一磨牙有完整的牙周检查表。随后采用相关分析和回归分析评估下颌第一磨牙远舌根的形态学特征与骨缺损及牙周临床参数间的关系,包括临床附着缺失、探诊深度、牙龈退缩和根分叉病变情况。研究结果发现,中国东部地区人群中下颌第一磨牙远舌根在患者和牙位水平的患病率分别为29.4%和26.3%。多元线性回归分析表明,第一磨牙舌侧的骨缺损及临床附着丧失水平与位于横截面的远舌根与近中根的分离角呈负相关,而与年龄和位于冠状面上的远颊根与近中根的分离角呈正相关。综上,中国东部地区人群下颌第一磨牙远舌根患病率较高,而且下颌第一磨牙远舌根的形态特征与牙周状况具有相关性。本研究旨在提高下颌第一磨牙远舌根的早期诊断率,并对存在远舌根的第一磨牙的治疗决策提供重要的信息。
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Data availability statement
The datasets used and analyzed during the study are available from the corresponding author upon reasonable request.
References
Abella F, Patel S, Durán-Sindreu F, et al., 2012. Mandibular first molars with disto-lingual roots: review and clinical management. Int Endod J, 45(11):963–978. https://doi.org/10.1111/j.1365-2591.2012.02075.x
Aung NM, Myint KK, 2022. Three-rooted permanent mandibular first molars: a meta-analysis of prevalence. Int J Dent, 2022:9411076. https://doi.org/10.1155/2022/9411076
Blanchard SB, Derderian GM, Averitt TR, et al., 2012. Cervical enamel projections and associated pouch-like opening in mandibular furcations. J Periodontol, 83(2): 198–203. https://doi.org/10.1902/jop.2011.110088
Chandra SS, Chandra S, Shankar P, et al., 2011. Prevalence of radix entomolaris in mandibular permanent first molars: a study in a South Indian population. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 112(3):e77–e82. https://doi.org/10.1016/j.tripleo.2011.02.016
Chen QM, Wang YH, Shuai J, 2023. Current status and future prospects of stomatology research. J Zhejiang Univ-Sci B (Biomed & Biotechnol), 24(10):853–867. https://doi.org/10.1631/jzus.B2200702
Chen WP, Chang SH, Tang CY, et al., 2018. Composition analysis and feature selection of the oral microbiota associated with periodontal disease. Biomed Res Int, 2018: 3130607. https://doi.org/10.1155/2018/3130607
Curzon MEJ, 1973. Three-rooted mandibular permanent molars in English Caucasians. J Dent Res, 52(1): 181. https://doi.org/10.1177/00220345730520011901
Dannewitz B, Zeidler A, Hüsing J, et al., 2016. Loss of molars in periodontally treated patients: results 10 years and more after active periodontal therapy. J Clin Periodontol, 43(1):53–62. https://doi.org/10.1111/jcpe.12488
de Moor RJG, Deroose CAJG, Calberson FLG, 2004. The radix entomolaris in mandibular first molars: an endodontic challenge. Int Endod J, 37(11):789–799. https://doi.org/10.1111/j.1365-2591.2004.00870.x
Farhadian M, Shokouhi P, Torkzaban P, 2020. A decision support system based on support vector machine for diagnosis of periodontal disease. BMC Res Notes, 13:337. https://doi.org/10.1186/s13104-020-05180-5
Goldstein AR, 1979. Enamel pearls as a contributing factor in periodontal breakdown. J Am Dent Assoc, 99(2):210–211. https://doi.org/10.14219/jada.archive.1979.0258
Graetz C, Schützhold S, Plaumann A, et al., 2015. Prognostic factors for the loss of molars–an 18-years retrospective cohort study. J Clin Periodontol, 42(10):943–950. https://doi.org/10.1111/jcpe.12460
Gu YC, Lu Q, Wang HG, et al., 2010. Root canal morphology of permanent three-rooted mandibular first molars—Part I: pulp floor and root canal system. J Endod, 36(6):990–994. https://doi.org/10.1016/j.joen.2010.02.030
Hamp SE, Nyman S, Lindhe J, 1975. Periodontal treatment of multi rooted teeth. J Clin Periodontol, 2(3): 126–135. https://doi.org/10.1111/j.1600-051X.1975.tb01734.x
Ho DKL, Wong JHL, Pelekos G, et al., 2021. Prevalence and morphological characteristics of disto-lingual roots in mandibular first molars: a cone beam CT study with diagnostic and therapeutic implications. Clin Oral Invest, 25(6):4023–4030. https://doi.org/10.1007/s00784-020-03733-3
Hou GL, Tsai CC, 1993. Relationship between palatoradicular grooves and localized periodontitis. J Clin Periodontol, 20(9):678–682. https://doi.org/10.1111/j.1600-051x.1993.tb00715.x
Hsu CL, Huang JE, Chen HL, et al., 2021. The relationship of the occurrence between three-rooted deciduous mandibular second molars and three-rooted permanent mandibular first molars in children. J Dent Sci, 16(2):580–585. https://doi.org/10.1016/j.jds.2020.11.008
Huang RY, Lin CD, Lee MS, et al., 2007. Mandibular distolingual root: a consideration in periodontal therapy. J Periodontol, 78(8):1485–1490. https://doi.org/10.1902/jop.2007.060419
Huang RY, Cheng WC, Chen CJ, et al., 2010. Three-dimensional analysis of the root morphology of mandibular first molars with distolingual roots. Int Endod J, 43(6):478–484. https://doi.org/10.1111/j.1365-2591.2010.01702.x
Jang JK, Peters OA, Lee W, et al., 2013. Incidence of three roots and/or four root canals in the permanent mandibular first molars in a Korean sub-population. Clin Oral Invest, 17(1):105–111. https://doi.org/10.1007/s00784-012-0687-3
Kim KR, Song JS, Kim SO, et al., 2013. Morphological changes in the crown of mandibular molars with an additional distolingual root. Arch Oral Biol, 58(3):248–253. https://doi.org/10.1016/j.archoralbio.2012.07.015
Lee WC, Ni CW, Lin FG, et al., 2016. Crown morphology of the mandibular first molars with distolingual roots. J Dent Sci, 11(2):189–195. https://doi.org/10.1016/j.jds.2015.07.007
Lin ZT, Hu QG, Wang TM, et al., 2014. Use of CBCT to investigate the root canal morphology of mandibular incisors. Surg Radiol Anat, 36(9):877–882. https://doi.org/10.1007/s00276-014-1267-9
Misch KA, Yi ES, Sarment DP, 2006. Accuracy of cone beam computed tomography for periodontal defect measurements. J Periodontol, 77(7): 1261–1266. https://doi.org/10.1902/jop.2006.050367
Mol A, Balasundaram A, 2008. In vitro cone beam computed tomography imaging of periodontal bone. Dentomaxillofac Radiol, 37(6):319–324. https://doi.org/10.1259/dmfr/26475758
Nibali L, Zavattini A, Nagata K, et al., 2016. Tooth loss in molars with and without furcation involvement–a systematic review and meta-analysis. J Clin Periodontol, 43(2):156–166. https://doi.org/10.1111/jcpe.12497
Sharma P, Cockwell P, Dietrich T, et al., 2017. INfluence of Successful Periodontal Intervention in REnal Disease (INSPIRED): study protocol for a randomised controlled pilot clinical trial. Trials, 18:535. https://doi.org/10.1186/s13063-017-2236-5
Song JS, Kim SO, Choi BJ, et al., 2009. Incidence and relationship of an additional root in the mandibular first permanent molar and primary molars. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 107(1):e56–e60. https://doi.org/10.1016/j.tripleo.2008.09.004
Song JS, Choi HJ, Jung IY, et al., 2010. The prevalence and morphologic classification of distolingual roots in the mandibular molars in a Korean population. J Endod, 36(4): 653–657. https://doi.org/10.1016/j.joen.2009.10.007
Sperber GH, Moreau JL, 1998. Study of the number of roots and canals in Senegalese first permanent mandibular molars. Int Endod J, 31 (2): 117–122. https://doi.org/10.1046/j.1365-2591.1998.00126.x
Thurzo A, Urbanová W, Novák B, et al., 2022. Where is the artificial intelligence applied in dentistry? Systematic review and literature analysis. Healthcare, 10(7):1269. https://doi.org/10.3390/healthcare10071269
Tu MG, Tsai CC, Jou MJ, et al., 2007. Prevalence of three-rooted mandibular first molars among Taiwanese individuals. J Endod, 33(10):1163–1166. https://doi.org/10.1016/j.joen.2007.07.020
Tu MG, Huang HL, Hsue SS, et al., 2009. Detection of permanent three-rooted mandibular first molars by conebeam computed tomography imaging in Taiwanese individuals. J Endod, 35(4):503–507. https://doi.org/10.1016/j.joen.2008.12.013
Tonetti MS, Christiansen AL, Cortellini P, 2017. Vertical sub-classification predicts survival of molars with class II furcation involvement during supportive periodontal care. J Clin Periodontol, 44(11):1140–1144. https://doi.org/10.1111/jcpe.12789
Turner CG II, 1971. Three-rooted mandibular first permanent molars and the question of American Indian origins. Am J Phys Anthropol, 34(2):229–241. https://doi.org/10.1002/ajpa.1330340207
Woelber JP, Fleiner J, Rau J, et al., 2018. Accuracy and usefulness of CBCT in periodontology: a systematic review of the literature. Int J Periodontics Restorative Dent, 38(2): 289–297. https://doi.org/10.11607/prd.2751
Acknowledgments
This work was supported by the Key R&D Program of Zhejiang Province (No. 2022C03088), the National Natural Science Foundation of China (Nos. 82170953, 82001046, and 82203345), the Science Fund for Distinguished Young Scholars of Zhejiang Province (No. LR23H140001), and the Scientific Research Fund of Zhejiang Provincial Education Department (No. Y202147347), China.
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Feifei MAO contributed to the study design, data analysis, and writing the manuscript. Meng WANG contributed to the conception of the study and data acquisition, and assisted in drafting the manuscript. Shuai ZHOU contributed to the conception of the study and data acquisition. Yan ZHAO involved in the investigation and methodology of the study. Jiaping HUANG critically revised the manuscript. Fengying YIN and Haiping YANG participated in editing the manuscript. Pei-hui DING provided supervision for the study, contributed to the conception and design of the study, acquired funding, and participated in reviewing and editing the manuscript. All authors have read and approved the final manuscript, and therefore, have full access to all the data in the study and take responsibility for the integrity and security of the data.
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Feifei MAO, Meng WANG, Shuai ZHOU, Yan ZHAO, Jiaping HUANG, Fengying YIN, Haiping YANG, and Pei-hui DING declare no conflicts of interest.
The study protocol has been reviewed and approved by the Ethics Committee of the Stomatology Hospital, Zhejiang University School of Medicine (No. 2023-031) and registered in Chinese Clinical Trial Registry (No. ChiCTR2300074445).
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Mao, F., Wang, M., Zhou, S. et al. Clinical relevance of distolingual roots and periodontal status in mandibular first molars: a cross-sectional study employing CBCT analysis. J. Zhejiang Univ. Sci. B 25, 244–253 (2024). https://doi.org/10.1631/jzus.B2300586
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DOI: https://doi.org/10.1631/jzus.B2300586
Key words
- Distolingual root
- Mandibular first molar
- Periodontal clinical parameter
- Clinical attachment loss
- Cone beam computed tomography (CBCT)