Introduction

From the observation by Danis that bone healing was promoted by stabilization, even in the presence of compression, instrumentation and hardware were developed to allow functionally stable internal fixation by AO/ASIF pioneers Allgöwer, Müller, Schneider, and Willenegger, and were introduced to the field of orthopedics in the 1950s.1 The maxillofacial surgeons were exposed to these fixation concepts as a result of their close cooperation with the orthopedic surgeons and traumatologists over 30 years ago. Within the AO Group, this was seized and further adapted into the field of maxillofacial surgery by Spiessl and Schilli among others, who performed a series of clinical and laboratory research experiences that dealt with biomechanical and metallurgical problems, resulting in the development of a variety of stainless steel implants to provide stable internal fixation of the mandible. These implants provided rigid internal fixation of fracture and osteotomy segments via absolute stability supplemented by compression. The introduction of a reconstruction plate allowed for the bridging of defects. In his textbooks New Concepts in Maxillofacial Bone Surgery (1976) and Internal Fixation of the Mandible: A Manual of AO/ASIF Techniques (1989), Spiessl documented this development.2,3

Following these early successful experiences with functionally stable internal fixation of the mandible, the field of application was widened and finally included the entire craniomaxillofacial region. With the development of lighter and more biocompatible titanium implants, the concepts of internal hardware–supported osteosynthesis were able to evolve from the conceptual need for “rigid or absolutely stable internal fixation” to a “functionally stable internal fixation,” which is based on the surgeon’s judgment and experience to provide adequate protection from functional forces of the maturing callus and bone healing in each individual situation. Resorbable plates and screws are now able to provide adequate functionally stable internal fixation in selected circumstances without the need for possible hardware removal, and is an advance from purely metallic implants. These new AO/ASIF techniques for the application of internal fixation

to fractures of the entire craniomaxillofacial skeleton were reviewed in Greenberg’s 1993 textbook, Craniomaxillofacial Fractures: Principles of Internal Fixation Using the AO/ASIF Technique.4

This edition presents a complete representation of the progression of the field of craniomaxillofacial surgery as it has evolved from these earlier works. It represents the entire field as it has developed from traumatology and advanced into the entire range of craniomaxillofacial reconstructive and corrective bone surgery. By eliminating the sole focus on the biomechanical requirements of internal fixation and examining considerations regarding the surgical methods for operating on all these problems, the field of craniomaxillofacial surgery has matured as a result of these technical accomplishments. However, the continued importance of hardware in this evolution is evident through the development of rigid fixation applications for bone lengthening through the principles of distraction osteogenesis.

With the concurrent publication in 1998 of Prein’s Manual of Internal Fixation in the Cranio-Facial Skeleton: Techniques Recommended by the AO/ASIF Maxillofacial Group5, a concise presentation of the AO/ASIF surgical techniques in an atlas format is now available. These two new texts permit a clear understanding of craniomaxillofacial surgical techniques and clinical experience in a complementary manner.

It has always been the fundamental policy of the AO Group to develop a faculty to provide the education to use the implant materials prior to clinical application, which has brought considerable advantages for patients through the refinement of new surgical procedures, whether for treatment of trauma, tumors, or malformations. Regardless of the problem, there are major advantages for the management of them all.

This policy has impacted the educational process from internal pressures within the surgical community and increased public awareness because the use of these implants requires greater responsibility and improved accuracy in the performance of these techniques. When used correctly, through the appropriate learning of techniques, the benefit to the patient’s care is immeasurable. Whether it is greater comfort and safety

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gained from immediate function or decreased danger from infection, greater security is achieved by the stability of these methods.

From an economic point of view, there is a reduced burden on the public, which has gained from these developments in internal fixation, with decreased morbidity, disability, and mortality. The medical community, however, suffers because of longer operating time, decreased use of facilities, reduction in procedures, direct cost of equipment and implants, and the costs of continuing education. The question of what the future holds remains. Who will make the decisions regarding the availability of these highly effective, technically demanding techniques? Will this be guided directly and indirectly by national governments, municipalities, local hospitals, staff, or industrial establishments? Will the great advances of the past 25 years in the evolution of craniomaxillofacial surgery from issues related mainly to the mandible, with the progression to the entire skull, continue in an environment in which the ability of doctors to make decisions is impacted by the concern of others? In the future, who will develop new techniques? In the current environment, can there be a similar process as it related to metallurgically based implants, in the search of a superior material (e.g., bioresorbable ones)? The correct relationship between industry, medical and research personnel, and government, based on appropriate economic models, is necessary to permit the continued research and development that has until today brought the field of craniomaxillofacial surgery to its present state.

The chapters in this book will permit the reader to gain a

A.M. Greenberg and J. Prein

complete appreciation of the broad spectrum of problems in the craniomaxillofacial region that may be addressed by a variety of clinicians with subanatomic specializations. This is further demonstrated by the international array of representative colleagues from these various disciplines. We hope that with this inclusion of all of these specialists we can promote the necessary close cooperation between the disciplines, by showing that there cannot be any boundaries between these different groups. Rather, we hope for continued progress in the level of communication among these different specialties that has been of benefit to all concerned, especially the patients, through the continued availability of the resources necessary to advance the art and science of this evolving surgical subspecialty.

References

1.Müller ME, Allgöwer M, Schneider R, Willenegger H. Manual of Internal Fixation. New York: Springer-Verlag; 1990.

2.Spiessl B, ed. New Concepts in Maxillofacial Bone Surgery. New York: Springer-Verlag; 1976.

3.Spiessl B. Internal Fixation of the Mandible: A Manual of AO/ASIF Principles. New York: Springer-Verlag; 1989.

4.Greenberg AM, ed. Craniomaxillofacial Fractures: Principles of Internal Fixation Using the AO/ASIF Technique. New York: Springer-Verlag; 1993.

5.Prein J, ed. Manual of Internal Fixation in the Cranio-Facial Skeleton: Techniques Recommended by the AO/ASIF Maxillofacial Group. New York: Springer-Verlag; 1998.