reading

4.2 Implants for Restoration of Single Tooth Spaces in Areas of Low Esthetic Risk

4.3 Implants for Restoration of Short Edentulous Spaces in Areas of Low Esthetic Risk

4.4 Implants for Restoration of Extended Edentulous Spaces in Areas of Low Esthetic Risk

4.5 Implants for an Implant-supported Denture or a Full-arch Fixed Dental Prosthesis in the Edentulous Mandible

4.5.1 Clinical Case – Implant Placement in an Edentulous Mandible Following Extraction

4.6 Implants for Restoration of Single Tooth Spaces in Areas of High Esthetic Risk

4.6.1 Clinical Case–Missing Upper Central Incisor with Horizontal and Vertical Bony Deficiency

4.7 Implants for Restoration of Short Edentulous Spaces in Areas of High Esthetic Risk

4.7.1 Clinical Case–Three Upper Anterior Teeth Requiring Extraction and Replacement with an Implant FDP

4.8 Implants for Prosthetic Replacement in Long Edentulous Spaces in Sites of High Esthetic Risk

4.10.1 Clinical Case–Replacement of a Maxillary Central Incisor with an Implant Placed at the Time of Extraction

4.11.1 Clinical Case–Replacement of a Maxillary First Premolar with an Implant Placed at the Time of Extraction

6.2 A Straightforward Restorative Case – Replacement of a Maxillary First Molar

6.4 A Complex Esthetic Application – Immediate Implant Placement and Provisionalization

German National Library CIP Data

The German National Library has listed this publication in the German National Bibliography.
Detailed bibliographical data are available on the Internet at http://dnb.ddb.de.

All rights reserved. In particular, the materials published in the SAC Classification in Implant Dentistry are protected by copyright. Any reproduction, either in whole or in part, without the publisher’s prior written consent is prohibited. The information contained in the published materials can itself be protected by other intellectual property rights. Such information may not be used without the prior written consent of the respective intellectual property right owner.

Some of the manufacturer and product names referred to in this publication may be registered trademarks or proprietary names, even though specific reference to this fact is not made. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.

All rights reserved. This book or any part thereof may not be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher.

Coordination: Ä. Klebba (QPC Berlin)
Illustrations: U. Drewes (www.drewes.ch)
Graphic Concept: Wirz Corporate AG, CH-Zurich
Production: H. Rohde (QPC Berlin)
Printing: Bosch-Druck GmbH (www.bosch-druck.de)

Printed in Germany
ISBN: 1850973490

Acknowledgement

The authors wish to express their sincere thanks to Ms. Ute Drewes for the artwork and illustrations in this textbook and to Ms. Jeannie Wurz for her excellent assistance during the editing process. We would also like to thank Straumann Holding AG, our corporate partner, for their unwavering and ongoing support of the activities and publications of the ITI.

Foreword

The rapid development of clinical techniques and biomaterials in implant dentistry has led to an expansion in the clinical indications for this modality of treatment. Implant dentistry now forms an integral part of everyday dental practice. However, education in implant dentistry for most dentists occurs after graduation with little emphasis on the identification of treatment complexity and risks. Since 2003, the International Team for Implantology (ITI) has recommended the SAC Classification to categorize treatment procedures into three levels of difficulty - Straightforward, Advanced and Complex.

In March 2007, the ITI organized a conference involving a multi-disciplinary group of 28 clinicians who met in Mallorca, Spain to standardize the application of the SAC Classification. The ITI is proud to be able to publish the proceedings of the conference in this volume.

The aim of the ITI is to promote and disseminate knowledge in all aspects of implant dentistry and related tissue regeneration. Together with the ITI Treatment Guide series, this book furthers the desire of the ITI to support the development of practical tools for clinicians and educators in dental implantology. The ITI recommends this book to all professionals in this field.

Editors and Authors

Anthony Dawson, MDS
Suite 7, 12 Napier Close
Deakin, ACT, 2600, Australia
E-mail: tony@canberraprosthodontics.com.au

Stephen Chen, MDSc, PhD
The University of Melbourne
School of Dental Science
720 Swanston Street
Melbourne, VIC 3010, Australia
E-Mail: schen@balwynperio.com.au

Daniel Buser, DMD, Professor
University of Berne
Department of Oral Surgery and Stomatology
School of Dental Medicine
Freiburgstrasse 7, 3010 Bern, Switzerland
E-Mail: daniel.buser@zmk.unibe.ch

Luca Cordaro MD, DDS, PhD
Eastman Dental Hospital, Roma
Head: Department of Periodontics and Prosthodontics
Via Guido D' Arezzo 2, Roma 00198, Italy
E-mail: lucacordaro@usa.net

William C. Martin, DMD, MS
University of Florida, College of Dentistry
Clinical Associate Professor,
Center for Implant Dentistry
Department of Oral and Maxillofacial Surgery
1600 W Archer Road, D7-6, Gainesville, FL 32610, USA
E-Mail: wmartin@dental.ufl.edu

Urs C. Belser, DMD, Professor
University of Geneva
Department of Prosthodontics
School of Dental Medicine
Rue Barthélemy-Menn 19, 1211 Genève 4, Switzerland
E-Mail: urs.belser@medecine.unige.ch

Contributors

Arne F. Boeckler
Martin-Luther-University Halle-Wittenberg
Associate Professor
Department of Prosthodontics
Grosse Steinstrasse 19, 06108 Halle (Saale)
Germany
E-Mail: arne.boeckler@medizin.uni-halle.de

Anthony J. Dickinson, BDSc, MSD
1564 Malvern Road
Glen Iris, VIC 3146, Australia
E-Mail: ajd1@iprimus.com.au

Christopher Evans, BDSc Hons (Qld), MDSc (Melb)
75 Asling St., Brighton
Melbourne, VIC 3186, Australia
E-Mail: cdjevans@mac.com

Hidekazu Hayashi, DDS, PhD
Family Dental Clinic
2 Saki-cho Nara, Nara 630-8003, Japan
E-Mail: Hide1@nike.eonet.ne.jp

Frank Higginbottom, DDS
3600 Gaston Avenue, Suite 1107
Dallas, TX 75246, USA
E-Mail: bottom@dallasesthetics.com

Dean Morton, BDS, MS
University of Louisville, School of Dentistry
Professor and Assistant Dean
Department of Diagnostic Sciences, Prosthodontics and Restorative Dentistry
501 S. Preston, Louisville, KY 40292, USA
E-Mail: dean.morton@louisville.edu

Zahra Rashid, BSc, DDS, MS, FRCD (C), FCDS (BC)
1466 West Hastings Street
Vancouver, BC, V6G 3J6, Canada
E-Mail: zrashid@shaw.ca

James Ruskin, DMD, MD
University of Florida, College of Dentistry
Professor and Director, Center for Implant Dentistry
Department of Oral And Maxillofacial Surgery
1600 W Archer Road, D7-6, Gainesville, FL 32610, USA
E-Mail: jruskin@dental.ufl.edu

Thomas G. Wilson Jr, DDS, PA
Periodontics and Dental Implants
5465 Blair Road, Suite 200
Dallas, TX 75231, USA
E-Mail: tom@tgwperio.com

1 An Introduction to the SAC Classification

A. Dawson, S. Chen, D. Buser

1.1 Introduction

Over the past 15 years, implant dentistry has progressed to become the standard of care for the rehabilitation of fully and partially edentulous patients. Clinical and technological advances have led to an expansion of the indications for implant therapy, providing increased opportunities for dental practitioners to become involved in the delivery of care. Along with these advances there has been an increase in the complexity of treatment being recommended to patients. This has increased the need for clinicians in the field of implant dentistry to be able to provide surgical and restorative therapy at an appropriate level of care.

It has long been recognized that clinical situations present with different levels of difficulty, and with different degrees of risk for esthetic, restorative and surgical complications. To date, there is no widely accepted classification system in implant dentistry aimed at defining the level of treatment complexity and the potential for complications. To assist clinicians in evaluating the degree of difficulty of individual cases, the International Team for Implantology (ITI) organized a Consensus Conference in Palma de Mallorca, Spain, from March 13^th to 15^th, 2007. The aim of the conference was to provide guidelines for various types of restorative and surgical cases based on a system referred to as the Straightforward, Advanced and Complex classification system (SAC).

These guidelines will provide clinicians with a reference for selecting appropriate cases and planning implant therapy. As well, this book will serve as a useful tool for academics wishing to design implant training programs with incremental levels of difficulty.

1.2 List of Consensus Conference Participants

This text documents the proceedings of a SAC Consensus Conference held by the International Team for Implantology (ITI) in Palma de Mallorca, Spain, over the period March 13^th to 15^th, 2007. The following individuals contributed to the consensus statements of this conference and the content of this publication:

1.3 Introduction to the SAC Classification

The SAC Classification is an assessment of the potential difficulty and risk of a case, and serves as a guide for clinicians in both case selection and treatment planning. Classifications of Straightforward (low difficulty and low risk), Advanced (moderate difficulty and moderate risk), and Complex (high difficulty and high risk) may be assigned to a case for both restorative and surgical aspects. The knowledge, skill and experience of individual clinicians, however, introduces subjectivity by influencing their perception of what a specific case may be classified as. The aim of this book is to bring objectivity to this process with respect to the “standard” presentation of clinical cases. It should be recognized, however, that the classification of individual cases may be altered as a consequence of modifying factors. These factors will be outlined in later chapters of this book.

The first SAC Classification was described by Sailer and Pajarola in an atlas of oral surgery (Sailer and Pajarola 1999). The authors described in detail various clinical situations for procedures in oral surgery, such as the removal of third molars, and proposed the classification S = Simple, A = Advanced, and C = Complex. The SAC Classification was then adopted in 1999 by the Swiss Society of Oral Implantology (SSOI) during a one-week congress on quality guidelines in dentistry. The working group of the SSOI developed this SAC Classification from a surgical and prosthetic point of view for various clinical situations in implant dentistry. This SAC Classification was then adopted by the International Team for Implantology in 2003 during the ITI Consensus Conference in Gstaad, Switzerland. The surgical SAC Classification was presented in the proceedings of this conference (Buser et al. 2004). The ITI Education Core Group decided in 2006 to slightly modify the original classification by changing the term Simple to Straightforward.

The following chapter provides a review of the SAC Classification, its applications and its determinants. Criteria for categorization of case types were established, and normative classifications (see the following chapter for definitions) for individual case types were assigned. Subsequent chapters will detail the application of the SAC Classification in the surgical and restorative fields of implant dentistry. The effects of modifying factors and complications on the normative classification of cases will also be presented and discussed.

Although it is primarily designed as a guide for identification of the level of difficulty of individual cases, the SAC Classification may also be used as a tool for risk identification and patient management. Patients may be prepared for treatment by being given information on expected limitations, complications and outcomes based on the SAC Classification. This in turn would allow patients to form realistic expectations of the potential outcome of therapy. Consequently, the SAC Classification has a number of potential audiences and uses. For novice implant clinicians, the SAC Classification provides a case selection and treatment planning tool which can help them develop their experience in implant dentistry in a responsible and incremental manner. More experienced clinicians may find somewhat less use in these areas, but might find this a useful framework for planning implant treatments and for identifying, and thus potentially controlling, risk.

The SAC Classification may also be applied throughout the treatment process. A normative classification, based on the site and type of clinical presentation, may be altered by patient-specific factors. The assigned classification may be further modified during the active treatment phases, if required.

2 The Determinants of the SAC Classification

A. Dawson, S.Chen

2.1 Definitions

Process: The implant dentistry “process” is defined as the full range of issues pertaining to assessment, planning, management of treatment, and subsequent maintenance of the implant and prosthetic reconstruction; it does not merely refer to the clinical treatment procedures that are involved.

Normative: In this context, “normative” relates to the classification that conforms to the norm, or standard, for a given clinical situation in implant dentistry. The normative classification relates to the most likely representation of the classification of a case. The normative classification may alter as a result of modifying factors and/or complications.

Timing of implant placement: A number of different classifications have been used to describe the timing of implant placement after tooth extraction. In this book, the classification detailed by Chen and Buser (2008), which is a modification of the classification proposed by Hämmerle et al. (2004), will be used. This classification is summarized in Table 1.

*Table 1. Classification of the Timing of Implant Placement following Tooth Extraction (Chen and Buser 2008).*
Classification	Descriptive Terminology	Period after Tooth Extraction	Desired Clinical Situation at Implant Placement
Type 1	Immediate placement	Immediately following extraction	Post-extraction site with no healing of bone or soft tissues
Type 2	Early placement with soft-tissue healing	Typically 4 to 8 weeks	Post-extraction site with healed soft tissue but without significant bone healing
Type 3	Early placement with partial bone healing	Typically 12 to 16 weeks	Post-extraction site with healed soft tissues and with significant bone healing
Type 4	Late placement	Typically 6 months or longer	Fully healed post-extraction site

Implant loading protocol: In discussions relating to the systems for loading implants after implant placement, the definitions used by Cochran et al. (2004) will be used. These are summarized in Table 2.

2.2 Assumptions

This classification assumes that appropriate training, preparation and care are devoted to the planning and implementation of treatment plans. No classification can adequately address cases or outcomes that deviate significantly from the norm. In addition, it is assumed that clinicians will be practicing within the bounds of their clinical competence and abilities. Thus, within each classification, the following general and specific assumptions are implied:

2.3 Determinants of Classification

The normative classification for a given type of case will be determined based on the criteria outlined below.

2.3.1 Esthetic vs. Non-Esthetic Sites

*Table 2. Definitions of Loading Protocols (Cochran et al. 2004).*
Loading Protocol	Definition
Immediate restoration	A restoration is inserted within 48 hours of implant placement, but not in occlusion with the opposing dentition
Immediate loading	A restoration is placed in occlusion with the opposing dentition within 48 hours of implant placement
Conventional loading	The prosthesis is attached after a healing period of 3 to 6 months
Early loading	A restoration in contact with the opposing dentition is placed at least 48 hours after implant placement but not later than 3 months afterwards
Delayed Loading	The prosthesis is attached in a procedure that takes place some time later than the conventional healing period of 3 to 6 months

The extent to which esthetic issues affect the process will be a general determinant. Cases in non-esthetic sites will have little or no esthetic risk, thus removing one potentially confounding factor. Straightforward cases must not, by definition, include any esthetic risk, and any case in the esthetic zone must be classified as either Advanced or Complex. In this context, an esthetic site is one in which the mucosal margins of teeth or tooth replacements will be visible upon full smile, or an area of esthetic importance to the patient (Belser et al. 2004).

2.3.2 Complexity of the Process

The level of complexity of an implant surgical or restorative treatment may be assessed by considering the number of steps involved in the procedure, and the number of areas in which an appropriate outcome must be achieved. As a general principle, the level of complexity rises with an increase in the number of steps involved and the number of objectives that must be achieved to attain a satisfactory result.

For example, a single-tooth replacement in a non-esthetic site may require limited planning. Surgery may involve an uncomplicated two-step process involving tooth extraction and subsequent implant placement some weeks later. The restorative phase of treatment may also involve an uncomplicated procedure. This case would, therefore, have a normative classification of Straightforward for both the surgical and restorative treatments. In contrast, a single-tooth restoration in an esthetic site will require more detailed assessment and planning, may involve more surgical and restorative steps, and must achieve somewhat more exacting outcomes. This process would have a normative classification of at least Advanced. While seemingly similar in application, these two examples demonstrate the increased complexity that attends cases in esthetically challenging sites.

Assessment of the complexity of a process can also be based on whether the outcome (and steps involved) can be predicted with some clarity. If they can, then classifications of Straightforward or Advanced may be appropriate (depending on other issues under consideration). In Complex cases the outcome is likely to be dependent on the success of intermediate procedures. This may require variations in the treatment plan and consideration of the associated contingencies. For example, if sinus grafting is necessary to place implants, the outcome of the procedure will, to a greater or lesser degree, affect the number, size and placement of implants, which in turn will affect the design of the final prosthesis. Thus, in the planning phase it is not possible to clearly envision the final outcome, leading to a classification of Complex.

2.3.3 Risks of Complications

No procedure is totally without risk of a mishap that may complicate the treatment or affect the long-term success and stability of the result. The SAC Classification can be used to identify and quantify these risks, thus allowing some contingency planning to be undertaken to control risk and minimize undesirable outcomes. In this sense, the SAC Classification can serve as a valuable risk management tool for dental practitioners.

Where risks are identified during the assessment and planning phases of the treatment process, measures can be initiated and included in the treatment plan to minimize the undesirable outcomes of potentially negative events. Patients can be counseled regarding these risks and warned of the potential down-side. Expectations can be controlled and patients prepared for sub-optimal outcomes should they arise.

What are areas of potential risk? The following list indicates broad areas that may influence the degree of difficulty of a clinical process, and thus the attendant SAC Classification:

These issues will be considered in more detail later in this text. However, during the case assessment and selection phase of management, the potential for these types of complications must be considered. It is this “potential” which contributes to the normative SAC Classification.

3 Modifying Factors

3.1 General Modifiers

S. Chen, A. Dawson

Normative classifications refer only to standard presentations of a case type. The following factors may modify these classifications, generally through increasing the difficulty of a treatment process:

3.1.1 Clinical Competence and Experience

While it is assumed that clinicians will undertake implant therapy that does not exceed their clinical abilities, it should be noted that the normative SAC Classification for a case type is independent of the clinicians’skill and competence. Thus, a Straightforward case will represent an uncomplicated procedure for both the novice and experienced clinician. On the other hand, a Complex case will be difficult to manage for the novice and experienced clinician alike. In this regard, the difference between the two is that the experienced clinician possesses the skill, competence and knowledge to manage the complex case and to deal with complications should they arise. In contrast, the novice clinician lacks the necessary skill and experience and would be best advised to refer such a case to someone with greater expertise.

3.1.2 Compromised Patient Health

Treatment of patients with compromised health is often more difficult in execution as well as more prone to complications (Table 1). For example, we know that smokers (Strietzel et al. 2007) and patients with uncontrolled diabetes mellitus (Moy et al. 2005, Ferreira et al. 2006) are more likely to have post-operative complications and implant failure and are regarded as at high risk for implant therapy. Other conditions can also have an impact in these areas, and must be assessed during the work-up for each case. These factors may be controlled to allow progression of the treatment, but the treatment process generally requires variations from standard treatment protocols.

3.1.3 Growth Considerations

Implants placed into the jaws of growing individuals represent a significant modifying factor. Experimental studies (Thilander et al. 1992) and clinical case reports in growing patients (Oesterle et al. 1993, Johansson et al. 1994, Westwood and Duncan 1996) have shown that implants act in a similar manner to ankylosed teeth by retarding the growth of the alveolar process in the immediate vicinity of the implant. The net effect is a relative infraocclusion and/or palatoversion of the implant (Figure 1). The clinical presentations of this are not only associated with esthetic issues (mismatch of incisal edges and gingival margins between the implant restoration and the contralateral tooth) but also with functional issues where restorations move into infraocclusion.

For these reasons, placement of implants should be postponed in young individuals until craniofacial/skeletal growth is complete (Koch et al. 1996). However, the growth period varies widely in children, and chronological age alone should not be used as a criterion. It has been recommended that a combination of methods be used to determine growth cessation, including serial cephalometric tracings, tooth eruption patterns within the arch (e.g., eruption of the second molar), evaluation of bodily growth in length, and evaluation of hand/wrist radiographs (Op Heij et al. 2003). It should be noted that individuals with a short or long face type may demonstrate further eruption of teeth adjacent to implants after the age of 20 years, posing a risk to esthetic and functional outcomes (Op Heij et al. 2006).

There is evidence that craniofacial growth may never cease completely, but may slowly continue throughout life (Behrents 1985). Over time, adaptive changes in tooth position may affect esthetics and function, requiring modification to or replacement of the implant-supported pros-theses in mature adults (Oesterle and Cronin 2000).

Risk Factor	Remarks
Medical	Severe bone disease causing impaired bone healing Immunological disease Medication with steroids Uncontrolled diabetes mellitus Irradiated bone Others
Periodontal	Active periodontal disease History of refractive periodontitis Genetic predisposition
Oral Hygiene/Compliance	Home care measured by gingival indices Personality, intellectual aspects
Occlusion	Bruxism

Inhaltsverzeichnis

The SAC Classification in Implant Dentistry

Authors:

A. Dawson

S. Chen

D. Buser

L. Cordaro

W. Martin

U. Belser

Editors: