The role of basic biologic research has frequently been portrayed as the identification of factors and processes that participate in clinical functions, and test the validity of any hypothesis regarding the efficacy and safety of new and old clinical methods. The specialty of orthodontics has benefitted from this relentless flow of new information, derived from a plethora of publications in numerous scientific periodicals, which focused on mechanism of mechanotransduction, the birth, life and death of the osteoclast, the molecular genetics of bone modeling and remodeling, and the effects of hormones and drugs on soft and mineralized connective tissues. This ongoing growth in information is already affecting clinical orthodontics. One major concept gaining support is the proven ability of bone and periodontal fibroblastic cells to respond simultaneously to more than one signaling factor. Evidence in support of this principle has already led to the application, in addition to orthodontic force, of surgical procedures, vibrations, laser radiation, electricity, and vitamin D3. All of these factors have displayed an ability to enhance the velocity and reduce the duration of tooth movement. The orthodontist now has at his/her disposal a choice of methods, invasive and noninvasive, local and systemic, that can augment the pace of tissue changes that facilitate tooth movement. These mechanisms act on the tissue and cellular levels, and can be manipulated based on increasing knowledge derived from worldwide laboratory experiments and clinical trials, all of which elevate the clinical potential of orthodontics to attain positive results, with a long‐range stability, and with a low risk for undesirable side effects.
We are pleased to present this second edition of Biological Mechanisms of Tooth Movement, in which we have assembled chapters about topics closely related to the basic biologic aspects of orthodontics, which affect the movement of teeth during orthodontic treatment. It updates most of the subjects addressed in the first edition, and includes new topics, such as the search for efficient methods to accelerate tooth movement.
We would like to thank all our contributors who have demonstrated dedication to this project. We would also like to express our sincere appreciation to the book reviewers, who critically analyzed the first edition of the book and let us know its shortcomings so that the second edition is made much stronger. We express our gratitude to our publisher, Wiley‐Blackwell, especially Sophia Joyce, Hayley Wood, Jessica Evans, Sara Crowley‐Vigneau, and Katrina Hulme‐Cross, who helped us complete the project successfully. We would also like to thank the support staff, Jayavel Radhakrishnan, David Michael and all others, who worked tirelessly to facilitate this publication.
As we have stated in the preface to the first edition of this book, “we really hope that this compendium will convince the readers that the dentofacial complex is an integral part of the complete human body, and as such, is prone to be influenced by any factor, genetic or environmental, like any other region of the body.” Orthodontic academicians and clinicians increasingly recognize this principle and try to treat patients as humans, not merely as typodonts. We hope that this book will assist all orthodontists in this effort.
Vinod Krishnan Ze’ev Davidovitch Editors
Preface to the Third Edition
Oral health, as defined by the FDI World Dental Federation, is multifaceted and includes the ability to speak, smile, smell, taste, touch, chew, swallow, and convey a range of emotions through facial expressions with confidence and without pain, discomfort, or disease of the craniofacial complex. Oral health has a close relationship with the general health of an individual and dental treatment contributes to the overall wellbeing of the individual, which is a well‐established fact that remains undiminished. The definition from the FDI implicates that malocclusion is not only an aesthetic problem, and states that orthodontic treatment can prevent and intercept further oral diseases and improve quality of life. To effect this, and to reach the stated goal together with our patients, we need to have a broad knowledge ranging from basic science to psychology, or stated in another way, from molecule to man.
Orthodontic tooth movement is the outcome of subjecting teeth to a wide variety of mechanical forces, for long periods of time. This movement is totally dependent upon stimulation and activity of cells near the affected dental roots. Investigations of these cellular responses focus on molecular events on the nuclear, cytoplasmic, and plasma membrane levels. We are very pleased to discover that our initial effort to organize all research related to tooth movement ‘under one roof’ and the subsequent second edition of Biological Mechanisms of Tooth Movement has made its mark among researchers, academicians, residents, and clinicians, equally. It stimulated basic science research in orthodontics, leading to the creation of a strong scientific foundation for the specialty. A sizeable body of new information related to the biology of orthodontic tooth movement has emerged since the publication of the second edition of this book by Wiley‐Blackwell in 2015. Since then, reports on studies about the molecular biology of bone metabolism, root resorption, and relapse of orthodontic treatment outcomes have appeared in orthodontic literature. With Professor Anne Marie Kuijpers‐Jagtman joining the team, who has contributed extensively to tooth movement research and its clinical translation, we are sure that the third edition will be a ‘reading and learning treat’ to all those who embrace it.
We have made the utmost effort updating the contents of this third edition and organizing it into specific areas, with the aim of highlighting the recent findings emanating from basic research, and bring them to the attention of clinicians specializing in moving teeth to new positions, effectively and comfortably. This edition presents four new chapters (tissue reactions, periodontal microbiology, surgically assisted tooth movement, as well as micro‐osteo perforations) and extensive revision of existing ones, especially the third chapter on mechanisms of tooth movement with orthodontic force application.
We would like to thank all our contributors, who are experts in their research area and have demonstrated dedication to this project. We would also like to express our sincere appreciation to the book reviewers, who analyzed critically the first and second editions of the book, which helped us to improve this edition. We express our gratitude to our publisher, John Wiley & Sons, especially Loan Nguyen, Tanya McMullin, Susan Engelken, Jayadivya Saiprasad, Bhavya Boopathi and to our copy‐editor Jane Grisdale who helped us complete the project successfully. We would also like to thank the supporting staff who worked hard to facilitate this publication.
The third edition of the book is aimed at the same audience as the first and second edition – clinicians, academicians, and researchers in the field of orthodontics and allied specialties such as periodontists, bone biologists, and also basic science researchers. The book is also indispensable for postgraduates in orthodontics, not only to understand how but also why teeth can be moved. Our main goal is to decipher the minute details of the investigations on cellular responses, focusing on molecular events on the nuclear, cytoplasmic, and plasma membrane levels, and its cross‐interactions leading to tissue level changes. We attempt to provide clinically plausible translational data which lead to practising a better, biologically oriented orthodontic treatment. We really hope that the educated clinicians who follow these developments can collect pieces of the unfolding puzzle, and relate them to individual patients, leading to a ‘biologic‐friendly orthodontics.’
Vinod Krishnan Anne Marie Kuijpers‐Jagtman Ze’ev Davidovitch Editors
CHAPTER 1 Biological Basis of Orthodontic Tooth Movement: A Historical Perspective
Vinod Krishnan and Ze’ev Davidovitch
