The Sinus Bone Graft E-Book

Ole T. Jensen

• Herausgeber: Quintessence Publishing Co, Inc
• Kategorie: Fachliteratur
• Serie: Third Edition
• Sprache: Englisch

Seitenzahl: 751

Veröffentlichungsjahr: 2019

Beschreibung

As research proceeds on treatment of the resorbed posterior maxilla, new techniques and innovations continue to be adopted to solve this clinical problem. While the previous edition of this book provided detailed information on the types of grafting materials and procedures available at the time, this completely revised version looks to the future with new strategies for treatment, some of which avoid grafting altogether. This book not only reviews the time-tested lateral window approach for sinus elevation and grafting but also describes a variety of techniques to approach the sinus transcrestally with or without grafting material. One section of the book is devoted entirely to the different types of implants and implant placement techniques available, many of which are designed specifically to avoid sinus elevation. In addition to clinical case studies and descriptions of how to perform specific surgical procedures, this book includes discussions on the science of bone formation and how continued research brings us closer every day to the ultimate goal of using tissue engineering to completely regenerate new teeth. 288 pp; 948 illus; ©2019

Leseprobe

Dedication

For my loving family: my wife, Marty, and my three children, Sverre, Trygve, and Autumn.

Acknowledgments

I wish to acknowledge my surgical assistants, Cindy Formanek and Jennifer Chatting, and my auxiliary staff including Monique Stozek, Jenny Featheringill, Kathy Stenson, and Janet Zacharias.

— Ole T. Jensen

Library of Congress Cataloging-in-Publication Data

Names: Jensen, Ole T., editor.

Title: The sinus bone graft / [edited by] Ole T. Jensen.

Description: Third edition. | Batavia, IL : Quintessence Publishing Co Inc,[2018] | Includes bibliographical references and index.

Identifiers: LCCN 2018033872 | ISBN 9780867157918 (hardcover) | eISBN 9780867158380

Subjects: | MESH: Maxillary Sinus--surgery | Bone Transplantation--methods |Dental Implantation--methods | Reconstructive Surgical Procedures--methods Classification: LCC RF421 | NLM WV 345 | DDC 617.5/2--dc23

LC record available at https://lccn.loc.gov/2018033872

© 2019 Quintessence Publishing Co, Inc

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Printed in China

CONTENTS

Foreword by Tomas Albrektsson

Preface

In Memoriam: Carl Erwin Misch

Contributors

Introduction by Hilt Tatum Jr

Section I: Surgical Options for Bone Grafting

1 Bone Grafting Strategies for the Sinus Floor

Craig M. Misch

2 Diagnosis and Treatment of Sinus Infections

Ashish A. Patel | Eric J. Dierks

3 Osteoperiosteal Flaps for Sinus Grafting

Ole T. Jensen

4 The Alveolar Split Approach for Sinus Floor Intrusion

Len Tolstunov | Daniel R. Cullum | Ole T. Jensen

5 Complex Techniques for Posterior Maxillary Reconstruction

Nardy Casap | Heli Rushinek

Section II: Lateral and Transcrestal Sinus Elevation

6 Lateral Window Surgical Techniques for Sinus Elevation

Tiziano Testori | Riccardo Scaini | Matteo Deflorian | Stephen S. Wallace | Dennis P. Tarnow

7 Sinus Floor Augmentation Without Bone Grafting

Giovanni Cricchio | Lars Sennerby | Stefan Lundgren

8 Intraoperative Complications with the Lateral Window Technique

Stephen S. Wallace | Dennis P. Tarnow | Tiziano Testori

9 Transcrestal Window Surgical Technique for Sinus Elevation

Michael S. Block

10 Transcrestal Sinus Augmentation with Osseodensification

Salah Huwais | Ziv Mazor

11 Transcrestal Hydrodynamic Piezoelectric Sinus Elevation

Konstantin Gromov | Sergey B. Dolgov | Dong-Seok Sohn

Section III: Implant Placement in the Resorbed Posterior Maxilla

12 Lateral and Transcrestal Bone Grafting with Short Implants

Rolf Ewers | Mauro Marincola

13 Transsinus Implants

Tiziano Testori | Gabriele Rosano | Alessandro Lozza | Stephen S. Wallace

14 Guided Extrasinus Zygomatic and Pterygoid Implants

Nardy Casap | Michael Alterman

15 Navigation for Transsinus Placement of Zygomatic Implants

Yiqun Wu | Feng Wang | Wei Huang | Kuofeng Hung

16 Arch-Length Threshold for Using Zygomatic Implants

Nicholas J. Gregory | Ole T. Jensen

17 Pterygoid Implants

Stuart L. Graves | Lindsay L. Graves

18 The Nazalus Implant

Pietro Ferraris | Giovanni Nicoli | Ole T. Jensen

19 Ultrawide Implants in Molar Sites

Costa Nicolopoulos | Andriana Nikolopoulou

20 Restoration and Abutment Options

Alexandre Molinari | Sérgio Rocha Bernardes

Section IV: Evolution and Innovations in Maxillary Bone Regeneration

21 The Sinus Consensus Conference: Results and Innovations

Vincent J. Iacono | Howard H. Wang | Srinivas Rao Myneni Venkatasatya

22 Sharpey Fiber Biologic Model for Bone Formation

Martin Chin | Jean E. Aaron

23 Using BMP-2 to Increase Bone-to-Implant Contact

Byung-Ho Choi

24 Tissue-Engineered Bone and Cell-Conditioned Media

Hideharu Hibi | Wataru Katagiri | Shuhei Tsuchiya | Masahiro Omori | Minoru Ueda

25 Tissue Engineering of the Dental Organ for the Posterior Maxilla

Fugui Zhang | Dongzhe Song | Ping Ji | Tong-Chuan He | Ole T. Jensen

Index

FOREWORD

About 40 years ago, I defended my PhD thesis, Healing of Bone Grafts, under the tutorship of P-I Brånemark. I placed optical implants in bone tissue prior to grafting and in this manner was able to investigate what happened to the graft microvasculature after transplantation. Even if allogeneic or heterologous bone was available at the time (eg, in the Oswestry and Kiel bone banks), it was generally agreed that only autogenous bone provided adequate repair. Bank bone was mainly used for large orthopedic defects as a last resort. Some 20 years later, I participated in the consensus conference on sinus grafts arranged in the United States. At the same time, results of sinus grafts were so successful that it seemed irrelevant whether autogenous, allogeneic, or heterologous grafts were used. Lamentably, the clinical material available at the time was data collected from clinicians rather than data printed in peer-reviewed journals, and this seldom allows for a critical scientific analysis. Nevertheless, it was the first time I had heard colleagues claim that similar good clinical results could be achieved with types of grafts other than the conventionally used autograft.

Today, of course, we have a large bulk of evidence that many types of bone grafts function very well when placed in sinuses. Admittedly, as evidenced in one chapter of the present volume, in some cases we do not necessarily see improved clinical results of implants after grafting compared to nongrafting—the preparation of bone tissue may provide a satisfactory supply of autogenous bone particles for clinical success. However, this type of very simple autografting may not work in severely resorbed clinical cases, and clinicians trying it in cases with 2 to 4 mm of bone thickness are advised to carefully check implant stability after placement.

One commonly used source of sinus graft material today can be heterologous bone such as Bio-Oss (Geistlich). We investigated the long-term fate of sinus-grafted Bio-Oss particles 11 years after grafting and found them largely unchanged in size and morphology.1 These particles, like the implant, may represent a foreign body with osteoconductivity (ie, new bone growth that explains the good clinical results achieved). In fact, the clinical fate of autografts may be quite similar in behavior. We analyzed the histologic outcome of small autogenous bone columellas used to replace the ossicular bones in hearing impairment in humans. The actual grafts had died, but they continued to function clinically with clear evidence that new live bone grew on the surfaces of the old grafts.2

The main reason why a volume such as the third edition of The Sinus Bone Graft is so important depends on the clinical reports made available. Sinus grafts are indeed most positive for patient treatment and have since long proven their clinical efficacy. Dr Jensen, the editor of this book, is one of very few in the world who has experience from more than 30 years working with sinus grafts, and I can think of no one more suited to be editor of this volume. He has put together a great number of excellent contributors to write about their experiences with sinus grafts under different conditions. This book is highly recommended to anyone using oral implants, and since major innovations have been presented in this third edition, I would even recommend it to those who already own the previous editions.

Tomas Albrektsson, md, phd

Professor Emeritus

Department of Biomaterials

Institute of Clinical Sciences

Gothenburg University

Gothenburg, Sweden

Visiting Professor

Faculty of Odontology

Malmö University

Malmö, Sweden

References

1. Mordenfeld A, Hallman M, Johansson CB, Albrektsson T. Histological and histomorphometrical analyses of biopsies harvested 11 years after maxillary sinus floor augmentation with deproteinized bovine and autogenous bone. Clin Oral Implants Res 2010;21:961–970.

2. Kylén P, Albrektsson T, Ekvall L, Hellkvist H, Tjellström A. Survival of the cortical bone columella in ear surgery. Acta Otolaryngol 1987;104:158–165.

PREFACE

With each passing year, I continue to be amazed at how far we have come and how we continue to advance in the highly specialized procedure of sinus elevation and grafting. Only a few decades ago, the sinus elevation was performed in just one general dental office in Opelika, Alabama; it is now an international cross-specialty collaboration. As the techniques have evolved, so has this book. The third edition of The Sinus Bone Graft updates current scientific rationale and clinical practice for what continues to be a necessary procedure for posterior maxillary dental implant reconstruction. In this volume, attention is given to historical recognition of pioneers in this field, including Hilt Tatum, Philip Boyne, and Carl Misch. But there are countless contributors to sinus elevation, from the members of the 1996 Sinus Consensus Conference sponsored by the Academy of Osseointegration to the authors of the now over 2,000 publications concerning modifications related to sinus floor treatment.

In 1986, I made the pilgrimage taken by many general dentist implantologists before me to visit Dr Hilt Tatum’s office and learn firsthand from the master clinician. After observing him over a few days, I remember leaving in a kind of daze wondering if a “sinus lift,” as he called it, could be real. It wasn’t until 10 years later that a group of 38 clinicians met in Boston to present their early sinus elevation results. After everyone had presented their data, including disparate methods and modifications to the original procedure, we came to understand quite remarkably that we all had success! We were stunned, almost to silence, that Dr Tatum’s work had so summarily been replicated. From that point forward, the world of implant dentistry changed as the sinus elevation was confidently recommended to patients.

A few years later, after having collaborated in Sweden, I had a discussion with P-I Brånemark and Ulf Lekholm, who still viewed the sinus procedure with skepticism. At the time, Dr Brånemark was hatching the idea of the zygomatic implant and told me that the sinus graft might not be necessary after all. I did not understand his meaning then, but I do now. In addition to an overview of the types of graft material and techniques, this book is filled with alternatives to the sinus graft. Among them are the use of the zygomatic implant and the idea that the sinus membrane should be reflected but not necessarily grafted, as Stefan Lundgren has shown.

In 2011, I met separately with Tatum and Boyne, the two great innovators of the sinus floor bone graft, and recorded their independent creative thought processes firsthand. Interestingly, they both described inspiration being triggered by a problem of deficient interocclusal space. Though surgeons, they were thinking as restorative dentists, struggling with how to obtain room for crowns or a prosthesis, when the sudden thought occurred of developing bone “on the other side” (ie, on the sinus floor). Bone grafting had never solved a problem in this way before. Similarly, many of the innovators in this book—the best and the brightest minds throughout the world—continue to creatively solve a portion of the riddle that is regenerative medicine.

This collection of prescient advancements in sinus graft technology would clearly not be possible without these innovators and scientists, the doctors of medicine and dentistry. However, we must also recognize all those who participate in the art of healing a human being: the surgical and research assistants, auxiliary staff, supportive families, and of course the patients themselves. Thank you for your devotion to this worthy cause.

Ole T. Jensen

IN MEMORIAM: Carl Erwin Misch, DDS, MDS

Dr Carl Misch (left) and Dr Craig Misch (right) at the Academy of Osseointegration Annual Meeting, 2016.

“Being his brother I could feel I live in his shadow, but I never have and do not now. I live in his glow.”—Michael Morpurgo

In 2017, the dental profession and implant field lost a true icon: my brother, Dr Carl E. Misch. Carl often stated that his professional goal was to elevate the standard of care in implant dentistry, and he worked tirelessly in pursuit of that achievement. He had a gift for organizing and simplifying information and used that gift to develop numerous principles and classifications that became integral concepts in the origins of modern implant dentistry. Carl had the good fortune to meet Dr Hilt Tatum in the late 1970s and to be taught sinus bone grafting techniques from one of the originators of the procedure. He had exceptional clinical skills and was one of the first prosthodontists in the United States to perform complex implant surgeries. In 1987, Carl published the first classification for managing the posterior maxilla based on the amount of bone below the sinus. These practical guidelines are still relevant today and were included in the second edition of The Sinus Bone Graft. He was also an early proponent of using bone substitutes for sinus grafting and presented his data alongside me at the first Sinus Consensus Conference at Babson College in 1996.

Carl had a passion for learning and sharing information. He founded the Misch Implant Institute, a continuing education program with an organized curriculum on implant dentistry. He was also on the faculty at several dental schools and served as director of one of the first university-based implant programs at the University of Pittsburgh from 1986 to 1993. His lectures—enthusiastic, authoritative, charismatic, and personal—always captured the audience’s attention. This text, Contemporary Implant Dentistry (Mosby/Elsevier, 1993), was one of the first books detailing sinus anatomy, physiology, and surgical approaches to manage the atrophic posterior maxilla. This text is now in its third edition and is considered by many as the most complete reference on surgical and prosthetic implant topics. Carl was a prolific author and published over 100 peer-reviewed articles on various implant-related topics. His commitment to the profession truly changed the lives of his students, colleagues, and patients. Dr Carl Misch was a true pioneer, leader, professor, and master clinician of implantology. He had a remarkable career, and we will all miss his influence and passion for implant dentistry.

Craig M. Misch

CONTRIBUTORS

Jean E. Aaron,PhD

Bone Structural Biologist and Visiting Lecturer

School of Biomedical Sciences

University of Leeds

Leeds, United Kingdom

Michael Alterman,DMD

Director of Outpatient Clinic

Hadassah and Hebrew University Medical Center

Jerusalem, Israel

Sérgio Rocha Bernardes,BDS, MSc, PhD

Head of New Product Development and Clinical Practice

Neodent Global

Professor

Latin American Institute of Dental Research and Education

Curitiba, Brazil

Michael S. Block,DMD

Private Practice Limited to Oral and Maxillofacial Surgery

Metairie, Louisiana

Nardy Casap,DMD, MD

Professor and Chairman

Department of Oral and Maxillofacial Surgery

Hadassah and Hebrew University Medical Center

Jerusalem, Israel

Martin Chin,DDS

Private Practice Limited to Oral and Maxillofacial Surgery

San Francisco, California

Byung-Ho Choi,DDS, PhD

Professor

Department of Oral and Maxillofacial Surgery

Wonju College of Medicine

Yonsei University

Wonju, South Korea

Giovanni Cricchio,DDS, PhD

Research Fellow

Department of Oral and Maxillofacial Surgery

Umeå University

Umeå, Sweden

Daniel R. Cullum,DDS

Private Practice Limited to Oral and Maxillofacial Surgery

Coeur d’Alene, Idaho

Guest Lecturer

Department of Oral and Maxillofacial Surgery

Loma Linda University

Loma Linda, California

Guest Lecturer

Department of Oral and Maxillofacial Surgery

University of California, Los Angeles

Los Angeles, California

Matteo Deflorian,DDS

Tutor at the Section of Implant Dentistry and Oral Rehabilitation

Department of Biomedical, Surgical, and Dental Sciences

School of Medicine

University of Milan

Milan, Italy

Eric J. Dierks,DMD, MD

Private Practice Limited to Head and Neck Surgery

Portland, Oregon

Sergey B. Dolgov,DDS, MSD

Private Practice Limited to Periodontics and Implant Dentistry

Mankato, Minnesota

Rolf Ewers,MD, DMD, PhD

Chairman Emeritus

Department of Cranio-Maxillofacial and Oral Surgery

Medical University of Vienna

Vienna, Austria

Pietro Ferraris,MD, DDS

Private Practice Limited to Oral and Maxillofacial Surgery and Prosthodontics

Alessandria, Italy

Lindsay L. Graves,DMD

Resident

Division of Oral and Maxillofacial Surgery

UT Southwestern/Parkland Memorial Hospital

Dallas, Texas

Stuart L. Graves,DDS, MS

Private Practice Limited to Oral, Maxillofacial, and Implant Surgery

Burke, Virginia

Nicholas J. Gregory,DDS

Private Practice Limited to Oral and Maxillofacial Surgery

Monroe, Louisiana

Konstantin Gromov,DDS

Private Practice Limited to Periodontics and Implant Dentistry

Glenview, Illinois

Private Practice Limited to Perioprosthodontics and Implant Dentistry

Moscow, Russia

Tong-Chuan He,MD, PhD

Associate Professor

Department of Surgery

Biological Sciences Division

University of Chicago

Associate Professor and Director

Molecular Oncology Laboratory

Department of Orthopaedic Surgery and Rehabilitation Medicine

University of Chicago Medical Center

Chicago, Illinois

Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences

The Affiliated Hospital of Stomatology

Chongqing Medical University

Chongqing, China

Hideharu Hibi,DDS, PhD

Professor and Chair

Department of Oral and Maxillofacial Surgery

Nagoya University Graduate School of Medicine

Nagoya, Japan

Wei Huang,DDS, MS

Professor

Department of Oral Maxillofacial Implantology

Ninth People’s Hospital

School of Medicine

Shanghai Jiao Tong University

Shanghai, China

Kuofeng Hung,DDS, MS

Department of Oral Maxillofacial Implantology

Second Dental Clinic

Ninth People’s Hospital

School of Medicine

Shanghai Jiao Tong University

Shanghai, China

Salah Huwais,DDS

Adjunct Assistant Clinical Professor

Department of Restorative Sciences

School of Dentistry

University of Minnesota

Minneapolis, Minnesota

Private Practice Limited to Periodontics and Implantology

Jackson, Michigan

Vincent J. Iacono,DMD

SUNY Distinguished Service Professor, Tarrson Family Professor of Periodontology and Chair

Department of Periodontology

Director of Postdoctoral Education

Stony Brook School of Dental Medicine

Stony Brook, New York

Ole T. Jensen,DDS, MS

Adjunct Professor

Department of Oral and Maxillofacial Surgery

School of Dentistry

University of Utah

Salt Lake City, Utah

Ping Ji,DDS, PhD

Professor and President

Chongqing Key Laboratory of Oral Diseases

National Clinical Research Center for Oral Diseases

The Affiliated Hospital of Stomatology

Chongqing Medical University

Chongqing, China

Wataru Katagiri,DDS, PhD

Associate Professor

Division of Reconstructive Surgery and Oral and Maxillofacial Region

Niigata University Graduate School of Medical and Dental Sciences

Niigata, Japan

Alessandro Lozza,MD

Chief Assistant and Senior Consultant

Neurophysiopathy Service, IRCCS Mondino Foundation

Pavia, Italy

Stefan Lundgren,DDS, PhD

Professor and Chairman

Department of Oral and Maxillofacial Surgery

Umeå University

Umeå, Sweden

Mauro Marincola,DDS, MS

Professor and Clinical Director

International Implantology Center

Department of Implant Dentistry

University of Cartagena

Cartagena, Colombia

Ziv Mazor,DMD

Associate Professor

Department of Implantology

Titu Maiorescu University

Bucharest, Romania

Private Practice

Tel Aviv, Israel

Craig M. Misch,DDS, MDS

Clinical Associate Professor

Department of Periodontics/Prosthodontics

School of Dental Medicine

University of Florida

Gainesville, Florida

Private Practice Limited to Oral and Maxillofacial Surgery and Prosthodontics

Sarasota, Florida

Alexandre Molinari,DDS, MSc, PhD

Director

Clinical Professional Relations and Education

Neodent USA

Andover, Massachusetts

Visiting Professor

Latin American Institute of Dental Research and Education

Curitiba, Brazil

Srinivas Rao Myneni Venkatasatya,DDS, MS, PhD

Assistant Professor

Department of Periodontics

Stony Brook School of Dental Medicine

Stony Brook, New York

Giovanni Nicoli,MD

Maxillofacial Surgery Specialist

ASST Vallecamonica Hospital

Brescia, Italy

Costa Nicolopoulos,BDS, FFD

Private Practice Limited to Oral and Maxillofacial Surgery

Dubai, United Arab Emirates

Andriana Nikolopoulou,MD

Private Practice

Glyfada, Greece

Masahiro Omori,DDS, PhD

Postdoctoral Researcher

Department of Oral and Maxillofacial Surgery

Nagoya University Graduate School of Medicine

Nagoya, Japan

Ashish A. Patel,DDS, MD

Consultant at a Private Practice Limited to Head and Neck Surgery

Associate Professor

Department of Oral and Maxillofacial Surgery

School of Dentistry

Oregon Health and Science University

Portland, Oregon

Gabriele Rosano,DDS, PhD

Oral Surgeon

Lake Como Institute

Como, Italy

Heli Rushinek,DMD

Oral and Maxillofacial Surgeon

Department of Dentistry

Hadassah and Hebrew University Medical Center

Jerusalem, Israel

Riccardo Scaini,DDS

Tutor at the Section of Implant Dentistry and Oral Rehabilitation

Department of Biomedical, Surgical, and Dental Sciences

IRCCS Istituto Ortopedico Galeazzi

University of Milan

Milan, Italy

Lars Sennerby,DDS, PhD

Professor

Institute of Odontology

Sahlgrenska Academy

University of Gothenburg

Gothenburg, Sweden

Dong-Seok Sohn,DDS, PhD

Professor and Chair

Department of Oral and Maxillofacial Surgery

Catholic University Medical Center of Daegu

Daegu, South Korea

Dongzhe Song,DDS, PhD

Molecular Oncology Laboratory

Department of Orthopaedic Surgery and Rehabilitation Medicine

University of Chicago Medical Center

Chicago, Illinois

State Key Laboratory of Oral Diseases

National Clinical Research Center for Oral Diseases

West China Hospital of Stomatology

Sichuan University

Chengdu, China

Dennis P. Tarnow,DDS

Clinical Professor and Director of Implant Education

College of Dental Medicine

Columbia University Irving Medical Center

New York, New York

Tiziano Testori,MD, DDS

Head of the Section of Implant Dentistry and Oral Rehabilitation

Department of Biomedical, Surgical, and Dental Sciences

University of Milan

Milan, Italy

Private Practice Limited to Implantology

Como, Italy

Adjunct Clinical Associate Professor

Department of Periodontics and Oral Medicine

School of Dentistry

University of Michigan

Ann Arbor, Michigan

Len Tolstunov,DDS, DMD

Associate Clinical Professor

School of Dentistry

University of the Pacific

Assistant Clinical Professor

School of Dentistry

University of California, San Francisco

Private Practice Limited to Oral and Maxillofacial Surgery

San Francisco, California

Shuhei Tsuchiya,DDS, PhD

Assistant Professor

Department of Oral and Maxillofacial Surgery

Nagoya University Graduate School of Medicine

Nagoya, Japan

Minoru Ueda,DDS, PhD

Professor Emeritus

Department of Oral and Maxillofacial Surgery

Nagoya University Graduate School of Medicine

Nagoya, Japan

Stephen S. Wallace,DDS

Clinical Associate Professor

Department of Periodontics

College of Dental Medicine

Columbia University

New York, New York

Private Practice Limited to Periodontics

Waterbury, Connecticut

Feng Wang,DDS, MD

Assistant Professor

Department of Oral Maxillofacial Implantology

Ninth People’s Hospital

School of Medicine

Shanghai Jiao Tong University

Shanghai, China

Howard H. Wang,DDS, MS, MPH, MBA

Private Practice Limited to Endodontics, Periodontics, and Implant Dentistry

New York, New York

Yiqun Wu,DDS, MD

Professor

Department of Oral Implantology

Ninth People’s Hospital

Second Dental Clinic

School of Medicine

Shanghai Jiao Tong University

Shanghai, China

Fugui Zhang,DDS, PhD

Molecular Oncology Laboratory

Department of Orthopaedic Surgery and Rehabilitation Medicine

University of Chicago Medical Center

Chicago, Illinois

Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences

The Affiliated Hospital of Stomatology

Chongqing Medical University

Chongqing, China

INTRODUCTION

Hilt Tatum Jr, DDS

When Dr Jensen contacted me about contributing to this third edition, I was uncertain. It had not been possible for me to participate in the Sinus Consensus Conference, and at the time I had not read his book. After reading the second edition, I realized it would be an honor to participate in this one.

The Preparation

My journey leading to the sinus augmentation procedure started in 1956, when I attended the first course on oral implants given in an American dental school, the Emory University School of Dentistry. The course was presented by Col Roy Bodine. My clinical experience began with 2 years of service in the Marine Hospital located in Savannah, Georgia. The next 2 years were spent doing full-mouth restorative dentistry in Savannah before I joined my father, Hilt Tatum Sr, and brother, Crawford Tatum, DDS, in Opelika, Alabama. There, our practice quickly became oriented to extensive restorative dentistry.

We recognized patients’ and our own dissatisfaction with free-end partial dentures and felt that this need could be met with the use of endosteal implants and fixed restorations. In an attempt to fix the problem, we acquired two sheets of commercially pure titanium, 0.25 inch thick and 0.75 inch thick. Using these sheets, we began to make and successfully use endosteal implants with different shapes that were designed to fit into the available bone found in different patients. After the implants were placed, we waited to load them until after a healing period similar to that used for mandibular fractures. However, because most of these patients had worn partial dentures for extended periods of time, we recognized the severe vertical bone loss and the need to restore the missing bone before the patients could receive implants.

The obvious answer to this need was to restore the missing bone volume with autogenous bone augmentation. However, as we began our preparation period before performing these surgeries, a startling event occurred. I had the chance to meet with Dr Frank Morgan, who had extensive experience doing bone grafting to treat battlefield wounds during the Vietnam War. When I discussed our plans with Frank, he shocked me with the following words: “Hilt, if you do this elective surgery on your private restorative patients, it will bury you with the complications you will encounter.” This completely stopped our efforts toward bone construction for some time.

Don Tillery, an oral surgeon and close friend, was aware of the preparation we had done and the effect that Dr Morgan’s advice had on our plans. In early 1969, Don called and said that he had seen a technique that he thought would safely meet our goal. He told me about an oral surgeon, Dr James Alley, who had successfully done a series of preprosthetic bone augmentations on edentulous mandibles before denture construction. We contacted Dr Alley, and he invited us to visit his office. We spent a week with him, observed two surgeries, and were able to see several patients who were at different periods of time postsurgically. The technique consisted of placing an autogenous rib (with no screws) on an edentulous mandible. This was followed by a 6-month unloaded healing period and then the construction of a new mandibular denture. He reported no postoperative healing complications.

The secret to Dr Alley’s success was in making two vertical incisions in the vestibule of each canine area, tunneling and mobilizing the soft tissue over the entire mandible, decorticating the crest of the mandible, shaping and placing the rib, and closing the remote incisions. The secret therefore was good asepsis, no incisions over the graft material, decortication, and an unloaded healing period. One patient who had worn the postoperative denture for 2 years appeared to have very little of the augmentation left.

Fig 1 Autogenous rib with one thickness (a) and two thicknesses (b) from 1970.

Fig 2(a and b) By 1980, we were using autogenous iliac bone for the maxilla and bilateral sinuses done with two vertical vestibular incisions.

These were our takeaways from this visit:

• Surgical asepsis would be critical.

• Decortication aided the augmentation union with the mandible.

• Remote incisions had prevented postoperative infections.

• Loading of the denture had largely destroyed the newly formed crestal bone.

• Placement of endosteal implants should not destroy the new crestal bone.

• Placement of endosteal implants should internally load and stimulate new crestal bone.

• Most importantly, we could safely begin to restore alveolar bone.

In January of 1970, we performed the first of four successful autogenous rib augmentations on posterior edentulous mandibles (Fig 1) harvested by Dr William Lazenby. Following his suggestion, we later began using the ilium as a bone source. Over a period of 9 years, Dr Lazenby and Dr Doyle Hanes routinely harvested bone for our augmentation patients (Fig 2) until I relocated my practice to St Petersburg, Florida, in 1979. Because all of these patients were treated in a hospital environment with remote incisions and Millipore filters (MilliporeSigma) over the augmented bone, we experienced a very limited number of postoperative surgical complications.

I have had the opportunity to give more than 2,000 podium presentations demonstrating these principles of creative remote incisions for all augmentation locations. These have been presented to a wide range of dental meetings, practitioners, and specialists. It surprised me that a large majority of alveolar augmentations have continued to be completed with crestal incisions over the augmentation material, sometimes resulting in complications. With good asepsis, remote incisions, adequate tissue mobilization, effective augmentation material, and precise tissue closures, complication rates will be significantly reduced.

We also found that augmented bone remained stable after implant placement, healing, and restoration. We did observe that when large augmentations were done within the esthetic zone, it was wise to maintain patients with provisional restorations in function for a period of 2 years before the definitive restorations were placed. This resulted in the most desirable esthetic results.

The Sinus Procedure

As our augmentation experience progressed, we recognized that it was impossible to do a vertical onlay augmentation in a posterior maxilla with no vertical loss and a severely pneumatized sinus without infringing on the vertical space required for the dental restorations. For the longest time, this seemed an insurmountable challenge. Then, in 1974, the thought occurred to me that we were looking at the problem backward and should be putting the bone inside of the sinus rather than on the crest. Immediately after this epiphany, I had parallel feelings of both exhilaration and fear. I was exhilarated by the thought that it might be possible, but the fear was that which any dentist might have on considering contact with a maxillary sinus.

During the remainder of 1974, we placed a number of posterior maxillary implants in the following way. We would either machine a titanium implant or cast a Vitallium implant that would fit into the medullary space between the sinus floor and the crest of the ridge (Fig 3). We also cast a try-in that had the same side dimensions but was longer than the implant. A remote palatal flap was lifted to expose the ridge crest, and curettes were used to prepare the implant site by removing bone to the floor of the sinus to match the dimension of the implant. The try-in was then fitted into this socket and lightly tapped to release the sinus floor. The floor and mucosal lining were vertically elevated a few millimeters, and some of the curetted bone was placed into the space around the elevated floor. The implant was then placed into the deepened socket and additional bone was placed over the implant to the crest of the ridge, with only the implant neck exposed. The flap was rotated and sutured on the palatal wall. The healing around each of these implants was uneventful, and they were restored.

Fig 3 Custom-made implants elevating the sinus floor and custom-made root form from 1974.

Fig 4 Sinus floor elevated by compressing bone and without entering the sinus.

Fig 5 Inflated Fogarty catheter elevating the sinus membrane.

We have always referred to this procedure as a sinus lift. By 1980, we had modified the technique into compressing the cancellous bone threads into an intertwined mat that could elevate the floor as it deepened the socket without entering the sinus (Fig 4). We now use these bone manipulation osteotomes to form the sockets, compress the cancellous bone, and elevate the sinus floor.

Our first sinus augmentation with autogenous, particulate, iliac bone was done in February of 1975. This, along with our next four augmentations, was done from the crest of the ridge and opened with a palatal flap. We then began to primarily use a crestal incision and prepare a sinus window anterior to the zygomatic buttress on the lateral wall of the maxilla. However, our fear of the word sinus was so strong that in the hospital operative notes, we would describe the operation as an inverted maxillary bone graft.

At the 1976 Alabama Implant Congress meeting in Birmingham, Alabama, we reported on the sinus augmentation procedure and the results we had observed during the previous 15 months. I was invited to make a presentation in the fall of 1977 on sinus augmentation at the American Academy of Implant Dentistry annual meeting and asked Dr Philip Boyne to join me. In a 1994 meeting of the Alabama Implant Congress (at the same podium from which I first presented in 1976), he confirmed our success with this procedure before an audience of more than 300 attendees.

During the first several years of sinus augmentations, we had limited instruments and relied heavily on modified Fogarty catheters to aid in the elevation of the sinus membrane. These were shortened to a few inches long and attached to a syringe. When slid under the sinus lining and gently inflated, they could safely lift the membrane (Fig 5). By 1978, we had created suitable instruments and no longer needed the Fogarty catheters.

Until 1984, autogenous iliac bone was our primary augmentation material. However, from 1972 until 1982, we were furnished some frozen human allograft by Dr Bill Hiatt from the VA-funded study, 1962–1982, for which he was a codirector. We established and maintained the same cryogenic banking capability as was used in the study and would always have a suitable human lymphocyte antigen match between the donor and recipient for anyone treated with this bone. Results comparable with autogenous bone were observed on the sinus augmentation patients treated with this allograft.

From 1978 forward, we began to utilize a titanium root form system I had developed, which became the first titanium root form system with FDA marketing approval (Fig 6). This system also included a selection of designs that were used to elevate the sinus floor and used the curetted bone that was harvested during the socket preparation (Fig 7).

From 1979 until 1983, we did the surgical cases for the US Food and Drug Administration (FDA) preclinical study on tricalcium phosphate ceramic (TCP) as a bone augmentation material. We evaluated and found this product to be successful for sinus augmentations, though slower in its replacement than human bone.

In the summer of 1982, Martin Lebowitz, DDS, MS, left the chairmanship of the OMS Department at the University of Florida School of Dentistry to join me. Following this, many of the Le Fort I surgical cases also had simultaneous sinus augmentations. Martin was left-handed and I was right-handed, which allowed us to both operate at the same time with the following steps:

• Careful attention was given to achieve optimum asepsis within each nasal passageway during preparation and intubation.

• After maxillary downfracture, a careful, meticulous freeing of the nasal mucosa from bone to prevent tears in this tissue was done. This was important to protect the augmentation material from risk of contamination from bacterial flora occurring in the nose.

• We also provided a hyperbaric oxygen chamber within our office to aid in the management of potential anaerobic infections.

In 1984, my son, Hilt Tatum III, DMD, joined our practice. During that same year, multiple augmentation products became available with the freeze-dried demineralized bone products reported as the most favorable. We used multiple products for sinus augmentations during this period, but by 1986, our clinical results were varied and confusing. We decided to evaluate each class of products by comparing results with histomorphometric evaluations taken from bilateral sinuses in the 4th postoperative month. We obtained three to five results from each type of the tested materials and were surprised by what we found. The best results (37% new bone) were obtained from irradiated cancellous human bone (ICB, Rocky Mountain Tissue Bank), and the second best was from 1- to 2-mm demineralized freeze-dried cortical bone chips (12% new bone).

Fig 6(a and b) Transmucosal implants and soft tissue reconstruction in augmented maxilla and bilateral sinuses.

Fig 7 Sinus implant selection and try-ins. This photograph shows 4 of the 16 sizes made.

Since 1988, the ICB from Rocky Mountain Tissue Bank has been our product of choice for sinus augmentations. This recognition that ICB provided a sinus augmentation product comparable with autogenous bone permitted a readily available and reliable material for in-office surgical procedures. Also, this product allowed us to perform lateral wall augmentations and place root-form implants rather than the special sinus implants. The average amount that we have used for each sinus has been 7 g.

In the mid-1990s, I designed and made a number of instruments to improve our ability to perform sinus procedures. These included flap retractors to fit over different shapes found on zygomatic buttresses and curettes made to fit the different anatomical areas found within sinuses. These instruments have significantly simplified and improved the precision of the surgeries.

Even when following a strict protocol under exact specified patient conditions, complications may occur. When a tear is present in the mobilized mucosal lining, excess tissue is folded over the tear and stabilized with a shaped collagen tape just prior to placing the bone. The tape will momentarily adhere to the lining, and by placing the bone immediately against the tape, it will stabilize the tape and hold the torn tissue in position. When postoperative infections occur, they will typically become symptomatic within a few days after the surgical procedure. Immediate attention, including culture and sensitivity testing, modification or expansion of antibiotic coverage with therapeutic doses, and further modification as directed following sensitivity testing, has proven to be effective in the majority of patients. If this does not completely eliminate the symptoms within a period of 7 to 14 days, removal of all augmentation material is usually indicated. If implants were placed during the augmentation procedure, this regimen would not be expected to be successful as a result of the biofilm-shielded bacterial colonies growing and shielded on the implants. In our 43 years of sinus augmentations, we have lost the grafts in less than 1% of the sinuses treated.

Vascularized Osteotomies

By 1980, we recognized that sinus and interpositional bone augmentations as well as free-flap procedures were safer and more precise than onlay procedures. Hoping to demonstrate this, I took a training course in microvascular surgery. We then attempted to replace onlay autogenous procedures with free-flap microvascular procedures using autogenous iliac sources. Though we could make the microvascular connections, we found that developing the correct bone shapes in the precise locations needed on the alveolar ridges was like fitting a square peg in a round hole. Still, the idea fascinated me, and in early 1982, we did a maxillary vascularized osteotomy procedure attempting to achieve a free-flap result by using the natural alveolus with its blood supply and without the need for microvascular surgery.

This was successful, so we published a paper on maxillary augmentations with the technique and have developed and expanded its utilization through the years.1 It instantly produces the results sought with a distraction osteogenesis procedure with minimal or no hardware. Typically, a long titanium screw (ie, 18 to 24 mm) is used to stabilize the vertically moved bone. ICB and irradiated corticocancellous (ICC) blocks are used for the interpositional material (Fig 8). Alterative vertical stabilization can be achieved with miniplates or ICC blocks. It is true that the shape of a healed alveolar ridge is not the shape of an alveolus surrounding teeth. However, the plasticity of vascularized alveolar bone, combined with the correct instruments, knowledge, and skill of bone manipulation, makes it possible to transform the vertically corrected but misshaped bone into a perfect socket. An implant can then be crestally positioned within the same location previously occupied by the root it is replacing (Figs 9 and 10). The correct use of this concept will produce the safest, simplest, and most precise correction of a vertical deficiency.

Fig 8(a to d) Tatum vascularized osteotomy (TVO). The goal is to regain bone attachment in the mandible by using a vertical fixation screw and implants.

Fig 9(a to d) Bone expansion, implant, and restorative treatment by Dr Jose Pedroza.

Fig 10(a to d) Bone expansion, implants, and restorative central crown restorations by Dr Ana Ayala.

We have used this to perform office procedures with intravenous sedation and local anesthesia, including the following:

• Move healed implants (Fig 11)

• Move segments of teeth and bone (Fig 12)

• Correct single implant sites (Fig 13)

• Move multiple edentulous segments (Fig 14)

• Correct vertical defects simultaneously with sinus augmentations (Fig 15)

• Move full maxillary arches (Fig 16)

The safety lies in the maintained vascularity and vitality of the bone, surgical asepsis, the interpositional location of the augmentation material, and the remoteness of the incisions. We have described this procedure as a Tatum vascularized osteotomy (TVO).

Fig 11(a to d) TVO used to move an implant.

Fig 12(a) Preoperative maxillary extrusion and an extreme buccal relationship. (b) TVO to correct abnormality and with implants placed. (c) Completed case with restorations by Dr Jose Pedroza.

Fig 13(a and b) Preoperative. (c to e) Using TVO. (f and g) Implant and restoration by Dr Jose Pedroza.

Fig 14(a and b) TVO correction before implant placement.

Fig 15 Simultaneous sinus augmentation and TVO, implants with bone expansion and manipulation of gingiva. (a) Preoperative. (b) Postoperative.

Fig 16(a to d) Full maxillary alveolus moved 8 mm down and 4 mm forward and crossbite correction all as in-office procedures.

The Future of Sinus Augmentations

It is our opinion that the future of the sinus augmentation procedure will include the simultaneous correction of vertical deficiencies. For a number of years, over half of the sinuses we have augmented have had simultaneous vertical corrections. These have been accomplished with either a TVO or an onlay block, and we will describe both. When a block is to be placed, an incision is made one tooth and one papilla anterior to the edentulous area and the same palatally to the midline or beyond, and a full-thickness flap is rotated over this tooth to prevent any incision from being present over the block. This flap must be completely elevated from the maxilla, including a buccal cut through the periosteum.

When the TVO is indicated, it can be correctly done and the implants later placed with bone manipulation. The TVO is safer than an onlay and produces the most precise results. The greater challenge here is that this requires the implant placements to be done with bone manipulation; this is a skill and an art that requires patience and training. The further complication is that we have a limited number of instructors with these special skills.

The TVO technique

Bone cuts are made with a set of microtomes that are designed for this procedure. The greater palatine vascularity to the soft tissue and bone should be preserved. The sinus elevation is completed as described previously and must be above the level of the hard palate. All bone cuts are made from the buccal without penetrating the palatal soft tissue and with progressive microtomes (5 mm, 7.5 mm, 10 mm, 12.5 mm, and 15 mm) to produce a straight cut.

Fig 17(a) After the elevation, collagen is placed against the lining. (b) ICB is placed, and a stent is added to allow placement of bone blocks with a screw for stabilization. (c) Palatal view of completed surgery and area to granulate.

Fig 18 Onlay block and sinus augmentation showing (a) incision, (b) remote vascularized flap elevation, and (c) occlusal view of block in place, palatal tissue, and area to granulate.

The anterior vertical cut is anterior to the vertical deficiency and is made through the alveolus to the level of the hard palate. Note that roots are never stripped of bone. A horizontal cut is made through the sinus and palatal slope just below the hard palate and anterior to the greater palatine foramen. The distal vertical cut is made through the tuberosity to the level of the hard palate or as a separation between the pterygoid plates and the maxilla to that level.

A superficial horizontal bone cut to protect the greater palatine bundle is made with a wide microtome to the distal vertical cut in the area of the greater palatine foramen. The microtome is then rotated downward to complete the horizontal fracture.

A periosteal elevator is slid through this horizontal cut (anterior to the greater palatine) to elevate and mobilize the soft tissue from the hard palate over to or across the midline (artery is safely within this tissue).

A semicircular incision is made (facing the surgical site) in the tissue over the hard palate. This permits the segment to be moved downward as this flap slides laterally—the greater palatine artery is avoided and always protected. The exposed bone will granulate over in 2 weeks.

The shaped collagen tape is placed against the sinus lining. A layer of ICB mixed with antibiotic is placed against the collagen tape to stabilize the collagen. A premade stent will be used to vertically position the mobilized bone, and it will be stabilized with ICC blocks, vertical screws, plates, and ICB to complete filling the sinus space below the elevated lining. A stent or dressing will be placed to hold this advanced soft tissue flap against the hard palate to create a fibrin seal (Fig 17).

When a vertically deficient maxilla is indicated for a sinus augmentation and the shape is not appropriate for a TVO, an ICC onlay block is indicated. The best results will be achieved by designing the flap to have no incisions over the augmentation and for the flap to be fully vascularized. There are a number of creative incision designs that can be used to provide access, maintain vascularity, reposition gingiva, or all of these tasks (Fig 18).

Conclusion

In 1977, we included this quote in our presentation: “The goal of modern implantology is to accept for treatment a patient at any stage of dental disease, atrophy, or trauma and—with general health permitting—restore them to normal contour, comfort, function, esthetics, and health.” Carl Misch opened each of his books with these goals. After 42 years and our over 2,800 sinus augmentations, this procedure has allowed us and many others to achieve these goals for countless patients.

Reference

1. Tatum H Jr. Endosteal implants. CDA J 1988;16(2):71–76.

Section I

CHAPTER 1

BONE GRAFTING STRATEGIES FOR THE SINUS FLOOR

Craig M. Misch, DDS, MDS

A primary diagnostic consideration of dental implant placement in the maxilla is the bone volume of the residual ridge. In the posterior maxilla, the maxillary sinus often limits the available bone for implant placement. The clinician can avoid the sinus by either selecting a shorter implant size or tilting the implant position away from the sinus cavity. Another option is to elevate the sinus mucosa to establish a new sinus floor at a more superior level. The goals of the sinus elevation procedure are to augment bone height in the posterior maxilla for dental implant placement, promote the development of a bone-to-implant interface contact, and enable long-term survival of the implants under prosthetic loading. This chapter discusses various strategies for managing the sinus floor, including surgical approaches, graft materials, and future directions.

Indications for Sinus Bone Grafting

During growth of the facial skeleton, the sinus cavities expand in volume. The floor of the maxillary sinus is often in close approximation to the posterior tooth roots. When posterior teeth are lost, the sinus further expands, reducing the amount of residual bone. Following extraction of the posterior teeth, there is also a loss of facial bone, resulting in medial resorption of the maxillary ridge. In addition, the edentulous posterior maxilla often has poorer bone quality. These conditions can compromise the placement of dental implants for prosthetic support.

The management of maxillary atrophy and sinus pneumatization for dental implant placement has evolved over the years. When sinus bone grafting was first developed, clinicians favored the use of longer dental implants. This was thought necessary for optimal biomechanical loading of the implant and prosthetic support. In addition, shorter machine-surfaced implants (< 10 mm) showed lower survival rates in the posterior maxilla.1 Under these constraints, it was often necessary to perform sinus bone grafting through a lateral window approach to allow placement of longer implants. An early classification protocol recommended lateral window sinus bone grafting when there was 8 mm or less of bone height below the sinus floor for placement of the maximum implant length (> 15 mm).2

However, improvements in implant materials, design, and surface properties have now led to the use of shorter dental implants. Many studies have even shown that the survival of short implants is the same as longer implants placed into grafted sinuses.3,4 Compared with short implants, sinus bone grafting has a higher incidence of complications, costs more, and requires additional surgical and healing time. However, short implants do have a higher risk of failure during the early healing period, which may be due to their reduced stability in softer bone.5

A clinical trend is to use shorter implant lengths in the posterior maxilla (Fig 1-1). This reduces the volume of bone grafting that is needed for implant placement and may even avoid the need for sinus augmentation. It may also allow the surgeon to consider an osteotome sinus floor elevation for short implant placement rather than using a lateral window technique.6 For example, a vertical bone height of 6 mm below the sinus floor would allow placement of a 6- to 9-mm implant via a transcrestal osteotome approach. Although there is no definitive bone dimension needed before considering sinus bone grafting, there is a lack of substantive long-term data on shorter implants (< 8 mm) in the posterior maxilla. The decision to place short implants versus sinus grafting for longer implants should be based on long-term studies, implant design, sinus pathology, surgical experience, and patient preferences.3 The need for sinus bone grafting is also reduced by using tilted implants to avoid the sinus and zygomatic implants that may be placed through or lateral to the maxillary sinus.

Fig 1-1 Clinical guidelines for managing the posterior maxilla based on bone height below the sinus floor. Overlapping colors indicate that multiple options can be considered.

Simultaneous Versus Delayed Implant Placement

The decision to place dental implants simultaneous with sinus bone grafting or staging placement after graft healing depends on several factors: the quantity and quality of bone below the sinus, implant design, clinical conditions, and experience of the surgeon. The advantages of simultaneous grafting and implant placement are decreased morbidity, lower costs, and shorter treatment duration. The edentulous posterior maxilla typically has a thin outer cortex with softer quality trabecular bone, and the sinus floor is a thin cortical shell. As such, the minimum bone height needed to place an implant simultaneous with grafting is approximately 4 to 5 mm.7 Experienced clinicians may be able to use methods to enhance primary implant stability in sites with less bone, such as underpreparing the osteotomy, osteotome expansion, osseodensification, and/or using tapered implants.8 Autogenous or allogeneic block bone grafts fixed to the sinus floor with implants have also been utilized.9

However, implant placement into sites with minimal residual bone may have higher risks of complications such as implant displacement and implant failure.10,11 If large sinus mucosa perforations are encountered during the augmentation procedure, it may be prudent to stage implant placement after graft healing. Grafting for simultaneous implant placement may be accomplished along the sinus floor via a lateral window or transcrestal approach. Another option is to place implants without any bone graft material, allowing the implant apices to tent the sinus membrane so blood clot or platelet concentrate alone can be used to provide enough matrix for bone ingrowth.

Delayed implant placement is performed after healing of a bone graft. The healing time may vary depending on the graft material used. Autogenous bone grafts heal faster, so using autograft as the sole material or combining it with bone substitutes can shorten the healing time requirements to 4 to 6 months.12 The use of a slow-resorbing graft material, such as bovine bone mineral or hydroxyapatite, may necessitate longer healing periods well exceeding 6 months.13 The bone graft material does not have to be completely incorporated before implant placement because additional healing time is allowed for implant integration, but the total healing period may still exceed 1 year with these slower resorbing graft materials. A systematic review revealed no significant differences in the survival of implants placed simultaneous with grafting or after graft healing.14 Therefore, the decision to place dental implants simultaneous with the graft or after healing is largely determined by the ability to achieve primary stability in native bone.

Sinus Grafting Techniques

When inadequate bone volume is present below the sinus for implant support, the sinus floor can be augmented. Conventional radiographs, such as periapical and panoramic films, are useful for preliminary screening of potential implant sites. Cone beam computed tomography can better assess the available bone and further evaluate sinus health and morphology. Cross-sectional images are useful to evaluate the ridge width, bone quality, and sinus floor. The buccopalatal distance of the sinus can influence the amount of graft material needed for augmentation and healing time requirements.15 There are two surgical approaches that can be used to elevate the sinus mucosa and place graft material: the lateral window or direct sinus elevation and the transcrestal or indirect sinus floor elevation.

These grafting techniques only address vertical bone deficiencies. The surgeon should also evaluate the residual ridge for facial bone loss and medial resorption following tooth loss. This may necessitate concomitant horizontal bone augmentation for ideal implant placement. In some cases, severe atrophy may also require vertical ridge augmentation (Fig 1-2).

Lateral window approach

The lateral window approach is performed in the posterior maxilla by creating an osteotomy over the lateral sinus wall and leaving the sinus mucosa intact. There have also been reports on using a palatal approach.16 The osteotomy may be created using rotary burs or piezoelectric tips to create an ovoid bone flap or complete removal of the overlying bone, providing an access opening for mucosal elevation. This approach requires vertical releasing incisions with greater flap reflection and retraction than a transcrestal sinus floor elevation. This greater surgical access can result in increased postoperative pain, facial swelling, and ecchymosis. In addition, vessels within the lateral sinus wall may be disrupted during preparation of the bony window, causing intraoperative bleeding. There may also be a greater risk of sinus mucosa perforation using this approach compared with a transcrestal elevation.17 However, open access allows for direct repair of mucosal disruption. Serious infections are rare but can occur with this more invasive surgical approach.

Fig 1-2(a) A bone scraper is used to collect particulate autograft and expose the sinus mucosa. (b) Autogenous bone is placed along the sinus floor and used for vertical ridge augmentation. (c) Implants are placed 4 months after graft healing.

The main advantages of using a lateral window approach are superior access, visibility of the mucosal elevation, and direct access to the sinus floor. This allows for placement of larger volumes of graft material and greater vertical bone augmentation. For this reason, it is the preferred technique for managing the pneumatized sinus with minimal residual bone below the sinus floor (0 to 5 mm). It would also be the preferred approach if additional simultaneous horizontal or vertical ridge augmentation of the posterior maxilla were needed. The posterior maxilla resorbs medially following tooth loss, and this pattern of bone loss may result in an unfavorable ridge relationship with the opposing mandibular dentition. If there is adequate residual bone height, implants may be placed simultaneous with the graft. Otherwise, implants are placed after a period of graft healing. The lateral window technique may also be useful in cases where sinus bone septa would complicate an internal osteotome lift. In this instance, two windows can be created on each side of the septa and the sinus mucosa can be elevated around and over the bony projection. A lateral window approach also allows for the removal of sinus pathology in conjunction with sinus grafting.

A systematic review on the lateral window sinus grafting technique including 59 articles and 13,162 implants found an overall implant survival of 93.6% (range: 61.2% to 100%).18 Evidence-based reviews have concluded that rough-surfaced implants have a significantly higher survival rate than machine-surfaced implants in lateral window sinus grafts. The use of a membrane to cover the window over the graft may also have a positive influence on implant survival. The use of a rough-surfaced implant and membrane coverage over the graft was found to improve implant survival to 98.6%.19Chapters 6 and 8 have more information on the lateral window technique.

Transcrestal approach

The transcrestal approach for sinus augmentation involves creating an osteotomy through the ridge crest of the posterior maxilla. This is usually done in conjunction with simultaneous implant placement. The osteotomy is typically prepared just short of the bony sinus floor. The thin layer of remaining bone can be gently upfractured and elevated with an osteotome or carefully reduced with a diamond bur or piezoelectric tip. Reverse-rotating osseodensification burs are another method to create the transcrestal osteotomy without disrupting the sinus mucosa (see chapter 10). This indirect method requires less flap manipulation, so it is less invasive than the lateral window technique. High patient satisfaction has been documented with this procedure.20

In cases where minimal additional bone height is needed for implant placement, it may not even be necessary to add graft material. The space between the implant apex and sinus mucosa fills with blood clot that heals into bone (see chapter 7). Platelet concentrate, such as platelet-rich fibrin (PRF), can also be used as a graft matrix. The fibrin clot is introduced into the osteotomy and compressed superiorly. The matrix of fibrin, embedded with platelet and leukocyte cytokines, can act as a cushion to protect the sinus membrane and facilitate bone healing. Larger amounts of bone augmentation can be achieved using particulate bone graft materials.6 Osteoconductive bone substitutes, such as bovine bone mineral or mineralized bone allograft or alloplasts, can be hydrated with sterile saline and placed into the osteotomy. The graft particles are gently compressed and elevated superiorly with an osteotome. Some slight resistance should be noted when the particles are compacted upward. Larger graft particles (> 1.0 mm) with irregular or sharp geometry are avoided because they may tear the sinus mucosa.

Grafting via the indirect method is less invasive but has the disadvantage that detection and management of sinus mucosa perforations is limited. Disruption of the sinus mucosa can occur during drilling of the osteotomy, mucosal elevation, or graft and implant placement. Although mucosal perforation is reported to be less frequent than with the lateral approach, the elevation of the sinus membrane should be regarded as technique sensitive.17 A small disc curette can be inserted into the osteotomy to detect the sinus floor and assess the dissection of the sinus membrane. Valsalva maneuver has been used to test for membrane perforation. The presence of air bubbles appearing through the osteotomy indicates a loss of mucosal integrity. It is difficult to blindly repair a sinus tear through the osteotomy. If a large perforation is encountered, the procedure may need to be abandoned. Another option is to create a lateral window for better access to repair. Benign paroxysmal positional vertigo has been documented as an infrequent but unpleasant complication of the osteotome technique.17

The transcrestal sinus floor elevation is typically used with simultaneous implant placement and when less bone augmentation is needed. An endoscopic examination found the increase in height by an osteotome technique alone should be limited to approximately 3 mm.21 However, using the indirect approach, bone gains between 3 and 9 mm have been reported.22 Greater bone gains can be obtained by using graft material versus no grafting. Experienced surgeons proficient in the transcrestal technique may manage cases with minimal available bone. Devices have also been developed to assist transcrestal grafting using hydraulic pressure or a balloon catheter to elevate the sinus mucosa.23 Although there is no definitive measurement of residual bone to indicate one technique over the other, improvements in the transcrestal method and a trend toward using shorter implants have lessened the need for the lateral approach.24 If the residual alveolar bone height is 6 mm, a transcrestal approach to elevate the sinus floor and place an 8-mm implant may lead to fewer complications than using a lateral window approach to place a longer implant.

A systematic review on the transcrestal osteotome technique including 34 studies and 3,119 implants found an overall implant survival of 96.7%.25 The vast majority of implant failures occurred early (< 1 year loading). Transcrestal sinus floor elevation was most predictable when the residual alveolar bone height was greater than 5 mm. Shorter implants (< 8 mm) demonstrated significantly lower cumulative survival rates than longer implants.25 For more information on the transcrestal approach, see chapter 9.

Bone Graft Materials

In the first publication on the sinus bone graft technique in 1980, Boyne and James26 used autogenous cancellous marrow from the ilium. Early Swedish studies on the reconstruction of the atrophic maxilla used iliac bone grafts with machine-surfaced implants.27 Autogenous bone was considered the gold standard of graft materials for oral and maxillofacial reconstructive surgeries. In addition, there was a limited choice of bone substitutes and a paucity of research on these alternative materials.