Ravindra Nanda Flavio Andres Uribe Temporary anchorage devices in orthodontics 2008 Mosby Elsevier 431 pages; 368 illustrations; $165

Abstract

Reviewed by Alex JacobsonThe introduction of temporary anchorage devices (TADs) has resulted in a paradigm shift in the overall perspective toward patient compliance, preservation of anchorage, and facilitation of treatment in various malocclusions. This book is divided into 5 parts, the first of which addresses the biologic properties of TADs. The introductory chapter of Part I, “Biological perspective,” reviews the historical perspective and the development of current concepts of microscrew and miniscrew systems relative to surgery, healing, and integration. The second chapter reviews bone biology and the factors predicting stability for mechanically retained and osteointegrated orthodontic TADs. The latter section of the chapter discusses common drugs that affect anchorage devices.Part II, “Diagnosis and treatment planning,” relates to the selection of ideal sites for mini-implant placement and to understanding how forces should be applied. Chapter 3 in this section reviews placement sites for mini-implants and how to apply orthodontic forces by using 3-dimensional finite element models. Case reports of 2 patients with dolichofacial and brachyfacial features are presented. Chapter 4 describes the K-1 mini-implant system, which achieves osteointegration after about 3 months of postoperative healing. The authors contend that these devices are proving to be more reliable than nonintegrated miniscrew TADs. Factors that must be considered when deciding to use skeletal anchorage are described in chapter 5. Also discussed are failures, predictors of clinical failure, and possible adverse effects.In Part III, “Biomechanical considerations,” chapter 6 is an overview of the mechanical principles of miniscrew orthodontics. Described are miniscrew dimensions, types, composition, the armamentarium for miniscrew placement, removal procedures, success rates, and complications. Shown and described in this substantial chapter are 4 challenging cases treated with various orthodontic appliance miniscrew combinations. Chapter 7, “Skeletal anchorage based on biomechanics,” demonstrates tooth movements once considered impossible with conventional orthodontic methods, such as significant molar intrusion, buccal segment intrusion, incisor intrusion, transverse expansion and 1- and 2-couple systems. Chapter 8 shows how with the use of miniscrews it is now possible to move teeth maximally, mimicking treatment results of orthognathic surgery in certain malocclusions such as Class I, Class II, and Class III dentoalveolar protrusion, anterior open bite, and Class II mandibular retrognathism.Management of the occlusal plane, the concern of Part IV, is critical in the control of orthodontic treatment. “Controlled occlusal plane changes using temporary anchorage devices” (chapter 9) describes and demonstrates control of the occlusal plane in all 3 dimensions of space. Problems of missing teeth, whether congenital or acquired, are complex and sometimes difficult to manage, especially wen several teeth are missing. Chapter 10, “Management of missing teeth using temporary anchorage devices,” addresses the wide range of tooth movements involved in such cases. Chapter 11, “Skeletal anchorage, different approaches,” outlines the ideal characteristics of microimplants followed by descriptions and case reports showing various methods of bone anchorage including microimplants, resorbable screws, bracket head type microimplants, and noninvasive implants. The features, surgical placement, and clinical application of microimplants as anchorage in sliding mechanics are addressed in chapter 12, “Clinical application of microimplants.” Also described are methods of retracting posterior teeth to resolve crowding, and microimplant use in clinical situations such as uprighting with 2 joined microimplants, molar intrusion, molar distalization, forced eruption, anchorage for periodontically compromised patients, and correction of the occlusal plane. “Clinical suitability of titanium microscrews for orthodontic anchorage,” chapter 13, reviews screw design, choice of placement site, diameter and length of miniscrews, intraoperative and postoperative complications, and failure rates. Chapter 14, “Treatment planning with endosseous implants for orthodontic anchorage and prosthodontic restoration,” addresses options for edentulous patients that can include cost, improved occlusion, fixed bridges vs implants, and temporary anchorage vs implants. Other considerations involve gathering an interdisciplinary team, developing a comprehensive treatment plan, implant loading to achieve osteointegration, and the biomechanics of endosseous implants.Part V, “Skeletal anchorage,” begins with chapter 15, describing a skeletal anchorage system with orthodontic miniplates and screws, the positioning and mechanics of miniplates, and the surgical procedures of implanting the miniplates. Described in Chapter 16, “Bone anchorage; a new concept in orthodontics,” are zygomatic implants which, according to the authors, are relatively easy to place and remove under local anesthesia. Zygomatic anchorage implants are used in various clinical situations when absolute anchorage is required. Shown are the benefits and advantages of this method compared with conventional methods. “Palatal anchorage,” chapter 17, refers to osteointegrated implants placed in the hard palate to be used as anchorage reinforcement in demanding orthodontic applications. Guidelines for the placement of a palatal implant, the surgical method, evaluation of the implant placement method, construction of the stationary anchorage appliance, orthodontic mechanics, and factors affecting the success of palatal implants are discussed. The concluding chapter, 18, “Skeletal anchorage in orthodontics using palatal implants,” focuses on some common skeletal orthodontic anchorage devices and their clinical uses and benefits. Discussed are the indications, placement and removal procedures, laboratory phase, and implants in adults and children. The 2 editors and 27 contributing experts have produced a most informative and profusely illustrated text on the potentials and usefulness of TADs in orthodontics. The book should be well received by clinicians willing to broaden their knowledge of the subject and those aiming to further refine their expertise in this field. Reviewed by Alex Jacobson The introduction of temporary anchorage devices (TADs) has resulted in a paradigm shift in the overall perspective toward patient compliance, preservation of anchorage, and facilitation of treatment in various malocclusions. This book is divided into 5 parts, the first of which addresses the biologic properties of TADs. The introductory chapter of Part I, “Biological perspective,” reviews the historical perspective and the development of current concepts of microscrew and miniscrew systems relative to surgery, healing, and integration. The second chapter reviews bone biology and the factors predicting stability for mechanically retained and osteointegrated orthodontic TADs. The latter section of the chapter discusses common drugs that affect anchorage devices. Part II, “Diagnosis and treatment planning,” relates to the selection of ideal sites for mini-implant placement and to understanding how forces should be applied. Chapter 3 in this section reviews placement sites for mini-implants and how to apply orthodontic forces by using 3-dimensional finite element models. Case reports of 2 patients with dolichofacial and brachyfacial features are presented. Chapter 4 describes the K-1 mini-implant system, which achieves osteointegration after about 3 months of postoperative healing. The authors contend that these devices are proving to be more reliable than nonintegrated miniscrew TADs. Factors that must be considered when deciding to use skeletal anchorage are described in chapter 5. Also discussed are failures, predictors of clinical failure, and possible adverse effects. In Part III, “Biomechanical considerations,” chapter 6 is an overview of the mechanical principles of miniscrew orthodontics. Described are miniscrew dimensions, types, composition, the armamentarium for miniscrew placement, removal procedures, success rates, and complications. Shown and described in this substantial chapter are 4 challenging cases treated with various orthodontic appliance miniscrew combinations. Chapter 7, “Skeletal anchorage based on biomechanics,” demonstrates tooth movements once considered impossible with conventional orthodontic methods, such as significant molar intrusion, buccal segment intrusion, incisor intrusion, transverse expansion and 1- and 2-couple systems. Chapter 8 shows how with the use of miniscrews it is now possible to move teeth maximally, mimicking treatment results of orthognathic surgery in certain malocclusions such as Class I, Class II, and Class III dentoalveolar protrusion, anterior open bite, and Class II mandibular retrognathism. Management of the occlusal plane, the concern of Part IV, is critical in the control of orthodontic treatment. “Controlled occlusal plane changes using temporary anchorage devices” (chapter 9) describes and demonstrates control of the occlusal plane in all 3 dimensions of space. Problems of missing teeth, whether congenital or acquired, are complex and sometimes difficult to manage, especially wen several teeth are missing. Chapter 10, “Management of missing teeth using temporary anchorage devices,” addresses the wide range of tooth movements involved in such cases. Chapter 11, “Skeletal anchorage, different approaches,” outlines the ideal characteristics of microimplants followed by descriptions and case reports showing various methods of bone anchorage including microimplants, resorbable screws, bracket head type microimplants, and noninvasive implants. The features, surgical placement, and clinical application of microimplants as anchorage in sliding mechanics are addressed in chapter 12, “Clinical application of microimplants.” Also described are methods of retracting posterior teeth to resolve crowding, and microimplant use in clinical situations such as uprighting with 2 joined microimplants, molar intrusion, molar distalization, forced eruption, anchorage for periodontically compromised patients, and correction of the occlusal plane. “Clinical suitability of titanium microscrews for orthodontic anchorage,” chapter 13, reviews screw design, choice of placement site, diameter and length of miniscrews, intraoperative and postoperative complications, and failure rates. Chapter 14, “Treatment planning with endosseous implants for orthodontic anchorage and prosthodontic restoration,” addresses options for edentulous patients that can include cost, improved occlusion, fixed bridges vs implants, and temporary anchorage vs implants. Other considerations involve gathering an interdisciplinary team, developing a comprehensive treatment plan, implant loading to achieve osteointegration, and the biomechanics of endosseous implants. Part V, “Skeletal anchorage,” begins with chapter 15, describing a skeletal anchorage system with orthodontic miniplates and screws, the positioning and mechanics of miniplates, and the surgical procedures of implanting the miniplates. Described in Chapter 16, “Bone anchorage; a new concept in orthodontics,” are zygomatic implants which, according to the authors, are relatively easy to place and remove under local anesthesia. Zygomatic anchorage implants are used in various clinical situations when absolute anchorage is required. Shown are the benefits and advantages of this method compared with conventional methods. “Palatal anchorage,” chapter 17, refers to osteointegrated implants placed in the hard palate to be used as anchorage reinforcement in demanding orthodontic applications. Guidelines for the placement of a palatal implant, the surgical method, evaluation of the implant placement method, construction of the stationary anchorage appliance, orthodontic mechanics, and factors affecting the success of palatal implants are discussed. The concluding chapter, 18, “Skeletal anchorage in orthodontics using palatal implants,” focuses on some common skeletal orthodontic anchorage devices and their clinical uses and benefits. Discussed are the indications, placement and removal procedures, laboratory phase, and implants in adults and children. The 2 editors and 27 contributing experts have produced a most informative and profusely illustrated text on the potentials and usefulness of TADs in orthodontics. The book should be well received by clinicians willing to broaden their knowledge of the subject and those aiming to further refine their expertise in this field.