Các biến thể giải phẫu được gặp hàng ngày bởi những chuyên gia đi vào khoang miệng (ví dụ: nha sĩ và bác sĩ phẫu thuật miệng) và các vùng lân cận. Do đó, để thực hành lâm sàng hàng ngày một cách tối ưu, cả thực tập sinh và chuyên gia trong các lĩnh vực này và những người khác (ví dụ: bác sĩ nội nha, bác sĩ nha chu, bác sĩ cấy ghép, bác sĩ giải phẫu, bác sĩ phẫu thuật hàm mặt, bác sĩ tai mũi họng, sinh viên nha khoa và bác sĩ vệ sinh nha khoa) nên biết về các biến thể phổ biến nhất được tìm thấy trong khoang miệng. Các Biến thể Giải phẫu trong Nha khoa Lâm sàng tìm cách cung cấp tài liệu tham khảo về chủ đề này. Cuốn sách bắt đầu bằng cách giới thiệu cho người đọc các biến thể giải phẫu theo quan điểm của các bác sĩ lâm sàng khác nhau — bác sĩ phẫu thuật răng hàm mặt, bác sĩ nha chu và bác sĩ nội nha. Các kiến thức giải phẫu mới nhất và các biến thể sau đó lần lượt được trình bày cho các xoang hàm trên, hàm trên, vòm miệng cứng, sàn miệng, môi, khớp thái dương hàm và răng. Trong mỗi chương, các chú thích lâm sàng được đưa vào để nâng cao hiểu biết về các mối quan hệ giữa phẫu thuật và giải phẫu. Các tác giả nổi tiếng quốc tế của văn bản đã được lựa chọn cẩn thận về chuyên môn của họ.
Anatomical Variations in Clinical Dentistry Joe Iwanaga R Shane Tubbs Editors 123 Anatomical Variations in Clinical Dentistry Joe Iwanaga • R. Shane Tubbs Editors Anatomical Variations in Clinical Dentistry Editors Joe Iwanaga Seattle Science Foundation Seattle, WA USA R Shane Tubbs Seattle Science Foundation Seattle, WA USA ISBN 978-3-319-97960-1 ISBN 978-3-319-97961-8 (eBook) https://doi.org/10.1007/978-3-319-97961-8 Library of Congress Control Number: 2018962487 © Springer Nature Switzerland AG 2019 This work is subject to copyright All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed The use of general descriptive names, registered names, trademarks, service marks, etc in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland Preface Anatomical variations are encountered on a daily basis by those specialists entering the oral cavity (e.g., dentists and oral surgeons) and adjacent regions Therefore, for optimal daily clinical practice, both trainees and professionals in these fields and others (e.g., endodontists, periodontists, implantologists, anatomists, maxillofacial surgeons, otolaryngologists, dental students, and dental hygienists) should be aware of the most common variants found in the oral cavity Anatomical Variations in Clinical Dentistry seeks to provide a go-to reference on this topic The book begins by introducing the reader to anatomical variations from the point of view of different clinical practitioners—oral and maxillofacial surgeons, periodontists, and endodontists The newest anatomical knowledge and variations are then presented in turn for the mandible, maxillary sinus, hard palate, floor of the mouth, lips, temporomandibular joint, and teeth In each chapter, clinical annotations are included in order to enhance the understanding of the relationships between surgery and anatomy The internationally renowned authors of the text have been carefully selected for their expertise Seattle, WA, USA Seattle, WA, USA Joe Iwanaga R. Shane Tubbs v Contents Part I Anatomical Variations from the Point of view of Clinical Practitioners 1 Anatomical Variations Relevant to Oral and Maxillofacial Surgeons���������������������������������������������������������������������� 3 Jingo Kusukawa 2 Anatomical Variations from the Point of View of the Periodontist�������������������������������������������������������������������������������������� 7 Daniel E Shin 3 Anatomical Issues Related to Endodontics���������������������������������������������� 17 Charles S Solomon and Sahng G Kim Part II Mandible 4 Anatomy and Variations of the Pterygomandibular Space�������������������� 27 Iwona M Tomaszewska, Matthew J Graves, Marcin Lipski, and Jerzy A Walocha 5 Anatomy and Variations of the Retromolar Fossa���������������������������������� 41 Puhan He, Mindy K Truong, and Shogo Kikuta 6 Anatomy and Variations of the Mental Foramen����������������������������������� 59 Joe Iwanaga and Paul J Choi 7 Variant Anatomy of the Torus Mandibularis������������������������������������������ 73 Soichiro Ibaragi Part III Maxillary Sinus 8 Anatomy and Variations of the Floor of the Maxillary Sinus���������������� 83 Katsuichiro Maruo, Charlotte Wilson, and Joe Iwanaga 9 Anatomy and Variations of the Posterior Superior Alveolar Artery and Nerve������������������������������������������������������������������������ 93 Iwona M Tomaszewska, Patrick Popieluszko, Krzysztof A Tomaszewski, and Jerzy A Walocha vii viii Contents Part IV Hard Palate 10 Anatomy and Variations of the Greater Palatine Foramen ������������������ 107 Iwona M Tomaszewska, Patrick Popieluszko, Krzysztof A Tomaszewski, and Jerzy A Walocha 11 Anatomy and Variations of the Incisive Foramen���������������������������������� 117 Iwona M Tomaszewska, Patrick Popieluszko, Krzysztof A Tomaszewski, and Jerzy A Walocha 12 Variant Anatomy of the Torus Palatinus�������������������������������������������������� 125 Tatsuo Okui Part V Lingual Plate and Oral Floor 13 Anatomy and Variations of the Submandibular Fossa�������������������������� 137 Yosuke Harazono 14 Anatomy and Variations of the Sublingual Space���������������������������������� 147 Norie Yoshioka 15 Anatomy and Variations of the Lingual Frenum and Sublingual Surface����������������������������������������������������������������������������� 157 Shogo Kikuta and Soichiro Ibaragi Part VI Lip 16 Anatomy and Variations of the Labial Frena������������������������������������������ 169 Koichi Watanabe and Yoko Tabira 17 Anatomy and Variations of the Lip���������������������������������������������������������� 177 Koichi Watanabe and Tsuyoshi Saga Part VII Temporomandibular Joint 18 Anatomy and Variations of the Temporomandibular Joint ������������������ 187 Rebecca C Ramdhan and Joe Iwanaga Part VIII Teeth 19 Variations in the Number of Teeth ���������������������������������������������������������� 205 Tsuyoshi Tanaka 20 Variations in the Anatomy of the Teeth���������������������������������������������������� 221 Yasuhiko Kamura 21 Abnormal Tooth Position�������������������������������������������������������������������������� 239 Masayoshi Uezono and Keiji Moriyama Part I Anatomical Variations from the Point of view of Clinical Practitioners Anatomical Variations Relevant to Oral and Maxillofacial Surgeons Jingo Kusukawa Anatomy provides the foundation of surgery and is the most basic and essential science in surgery It is indispensable not only for meeting diagnostic challenges but also for developing surgical procedures Therefore, anatomy is a basic requirement for all surgical specialties Oral and maxillofacial surgery specializes in treating pathological conditions and disorders, injuries, defects, deformities, and malformations in the hard and soft tissues of the oral cavity, jaws, face, and adjacent organs Therefore, oral and maxillofacial surgeons require specific skills that also necessitate detailed knowledge of the relationships among the anatomical structures encountered during surgical operations in this area Insufficient anatomical knowledge can result in serious complications and poor cosmetic or functional postoperative results Clinical anatomy, giving consideration to practical surgery, is crucial for enhancing diagnostic efficiency and performing a safe and effective operation In addition to fundamental knowledge of the clinical anatomy of the oral and maxillofacial region, we should deepen our understanding of anatomical changes during aging and anatomical variations among individuals Morphological changes caused by disuse atrophy of alveolar and jaw bones following tooth loss handicap the surgeon’s search for anatomical landmarks such as the piriform aperture and anterior nasal spine, incisive papilla (incisive canal), hamular notch, and neural foramina Decrease of the alveolar ridge height increases the risk for injury to nerves and blood vessels emerging from neural foramina including the greater palatine foramen (Fig. 1.1), the infraorbital foramen, and the mental foramen Narrowing of the alveolar ridge increases the risk that the surgeon’s scalpel blade leaves the alveolar crest and cuts deeply inside Furthermore, anatomical variations complicate the situation of the operation Such variations are potential risk factors in oral and maxillofacial surgery In J Kusukawa (*) Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Japan e-mail: kusukawa@med.kurume-u.ac.jp © Springer Nature Switzerland AG 2019 J Iwanaga, R S Tubbs (eds.), Anatomical Variations in Clinical Dentistry, https://doi.org/10.1007/978-3-319-97961-8_1 J Kusukawa Fig 1.1 Greater palatine foramen (arrow), nerve, and artery particular, variations of nerves and blood vessels entail the risk of serious complications Uncontrollable bleeding from blood vessel injuries can be life-threatening Permanent nerve injury has a serious negative effect on the patient’s quality of life To avoid such complications, surgeons should be familiar with anatomical variations as well as preventive care Third molar surgery remains the commonest procedure carried out by general dentists and oral surgeons One of the main concerns in third molar surgery is inferior alveolar nerve (IAN) injury The incidence of permanent IAN injury ranges from 0.35% to 8.4% (Sarikov and Juodzbalys 2014) Apart from third molar surgery, the IAN is at risk of trauma during oral surgery operations such as jaw cyst surgery, or implant surgery The IAN enters the mandible from the mandibular foramen, which is inside the mandibular ramus, passes through the mandibular canal, leaves from the mental foramen outside the mandibular body, and is distributed over the lower lip and mental region as the mental nerve (MN) To avoid unnecessary complications, we should recognize that there are many variations in the pathway of the IAN and MN. It is well known that the positional relationship between the third molar and mandibular canal corresponds to the incidence of IAN injury In addition, the prevalence of accessory mental foramina ranges from 2.0% to 13.0% (Iwanaga et al 2015) Such accessory foramina in the vicinity of the mental foramen are a potential risk for paresthesia of the lower lip and mental region Lingual nerve (LN) paralysis is serious complication in oral surgery As the LN runs along the lingual aspect of the mandible and reaches the tongue through the floor of the mouth, it can be injured by oral surgery operations including third molar surgery, jaw resection, grafting of the alveolar crest, salivary gland surgery, ... in the oral cavity Anatomical Variations in Clinical Dentistry seeks to provide a go-to reference on this topic The book begins by introducing the reader to anatomical variations from the point.. .Anatomical Variations in Clinical Dentistry Joe Iwanaga • R. Shane Tubbs Editors Anatomical Variations in Clinical Dentistry Editors Joe Iwanaga Seattle... © Springer Nature Switzerland AG 2019 J Iwanaga, R S Tubbs (eds.), Anatomical Variations in Clinical Dentistry, https://doi.org/10.1007/978-3-319-97961-8_2 2.2 D E Shin ommon Anatomical Variations