Orthodontic Treatment of Impacted Teeth. Adrian Becker

by the second number 3: a right maxillary canine would be denoted 13; a left mandibular second molar would be assigned 37; and a mandibular right lateral incisor 42. All four canines are rarely impacted in the same individual, but when this occurs, it will be appreciated that 13, 23, 33 and 43 will be more easily recognizable than the 6, 11, 22 and 27 of the so‐called ‘universal’ numbering system, which seems to have achieved acceptance largely in the USA. (We have occasionally used the hash sign # in front of the number, in order to clearly differentiate the tooth number from other numbers in the text.)

      Similarly, numbering the deciduous teeth employs the quadrant system in the same order, labelled from 5 to 8 and the teeth numbered 1 to 5. Thus, the maxillary deciduous right central incisor is defined as 51 and an infra‐occluded mandibular right deciduous second molar is numbered 85.

      I am grateful to each of my co‐authors for having enthusiastically responded to my invitation to write a specific chapter in this volume and for having submitted their finished manuscripts ahead of the deadline I set for them. The chapter on biomechanics as it relates to impacted teeth was written and illustrated by Dr Ulrich Kritzler, who is in private practice in Warendorf, Germany and a regular contributor to the international orthodontic literature. The rapidly expanding popularity of clear aligners in orthodontics prompted me to invite a discussion of their use, suitability and the limitations of their application to the treatment of cases with impacted teeth. This has been authored by Prof. Dror Aizenbud, Chair of the Unit for Orthodontics and Craniofacial Anomalies in Haifa, Israel.

      For the past several years, I have availed myself of the expert services of Mr Amnon Leitner, perhaps the most knowledgeable and skilled master radiographic imaging technician I have ever had the good fortune to meet and to work with. I invited him to enlarge and update the chapter on diagnostic imaging, specifically with regard to cone beam computerized tomography. Several of his highly informative secondary reconstructions, 3D screenshots and video clips appear in that chapter and additional examples of his work may be seen in a number of other chapters.

      I am grateful to Dr Athina‐Maria Mavridou of KU Leuven (University of Leuven) in Belgium, a trained endodontist and an accomplished research scientist, who provided helpful comment on the histopathological aspect of my description of invasive cervical root resorption. ICRR is a specific pathological entity in its own right and is discussed in Chapter 10. The positive diagnosis of ICRR has serious repercussions in relation to the treatment of impacted teeth, yet it is substantially uncharted territory and rarely recognized by orthodontists.

      As in the second and third editions, I acknowledge the contribution to several chapters in the book, of Prof. Stella Chaushu, Chair of the Department of Orthodontics at the Hebrew University–Hadassah School of Dental Medicine, Jerusalem, Israel. For the past 25 years, our academic collaboration has achieved much in terms of basic and clinical research, particularly in the area of eruption disturbance. Tooth impaction has also been the subject of the many invited lectures and courses that we have conducted together internationally and this book largely represents the culmination of those years of endeavour, even from as early as 1964. It reflects many of the fruits of our joint academic collaboration.

Writing a text on the subject of impacted teeth involves filtering out the relevant and appropriate conclusions of published studies from the mass of orthodontic literature in general, and specifically honing in on those evidence‐based investigations published in the leading international, peer‐reviewed orthodontic journals. The treatment decisions made in individual cases or in small case series of the treatment of rare conditions cannot, by virtue of their small numbers, be founded on evidence that is other than anecdotal. This does not necessarily negate the validity of the decision to treat the next patient with the same condition in a similar manner. However, it must be understood that the decision can be justified on an empirical basis only and is likely to be dependent on careful patient selection; and it does obligate this and any other author to report the possibility of bias. I have tried to comply with this and hope that I have been successful in my diligence in the examples of treatments elaborated in the text.

      In my efforts to produce a readable and understandable narrative, I managed to persuade my brother Laurence (Shmuel) Becker to be responsible for the editing and proofreading of this work. He is a lawyer and is the first to admit that he knows absolutely nothing about orthodontics. His theory was that if he could understand what I have written in this volume and could follow the ideas and the logical sequence, then any orthodontist should be able to read, follow and understand the text and the ideas that I have tried to portray easily and painlessly. And so he has corrected, amended, shuffled words around, relocated sections and substituted my words for others that only a lawyer can produce. (He is probably the only other person who will have read the entire book at least five times over.) For all this, I am greatly in his debt.

      The wondrous workings of today’s desktop computers have provided me with the means to write this text, which would never have been possible using the steam‐propelled typewriter. However, my computer has also given me a false sense of security, learned from bitter experience. Many times in the past three years I lost material that I had spent days writing, either because I had failed to save it or because I had ‘copy‐pasted’ these sections into other files, which I promptly and unintentionally deleted. I cannot count the number of times that I called my son‐in‐law, Asher Cohen (also a lawyer), setting him the task of rediscovering them and putting me back into the business of writing. He found them every time, at break‐neck speed. I salute his alacrity and his digital skills!

      I closely identify with the legendary Danish pianist and comedian who, at the same advanced age as I am now, was still appearing on stage before large live audiences. At the end of one of his solo performances, Victor Borge acknowledged: ‘I wish to thank my parents for having made this possible and I wish to thank my children for having made it necessary.’

      Adrian Becker

      Jerusalem, Israel

      June 2021

      About the Companion Website

      This book is accompanied by a companion website.

      www.wiley.com/go/becker/orthodontic_treatment_impacted_teeth

      The website includes a series of Power Point presentations mainly of CBCT interpretation work‐ups and particularly in relation to diagnosis of impacted teeth. They contain embedded video clips illustrating methods for refining accurate positional identification or analysis of the teeth in 3D and in improving the qualitative recognition of pathologic entities.

      Each online resource is called out in the text by number for ease of location.

      View all animations in full screen by clicking the square button under the bar at the bottom right of the animation window.

1 General Principles Related to the Diagnosis and Treatment of Impacted Teeth

       Adrian Becker

        Dental age

        Assessing dental age in the clinical setting – the Jerusalem method

        When is a tooth considered to be impacted?

        Impacted teeth and local space loss

        Whose problem?