This textbook has taught thousands of orthodontists the importance of understanding biomechanics to ensure healthy, predictable movements in clinical practice, and this new edition will undoubtedly do the same for the new generations of students. Technology continues to advance in orthodontics, but no technology can replace a sound understanding of how the teeth move in their periodontal apparatus and how they can be pushed or pulled to get where they need to be. This book is the difference between an orthodontist who can move teeth and an orthodontist who can plan cases with predictability and achieve the sought-after results.