Techniques for Success With Implants in the Esthetic Zone

Techniques for Success with Implants in the Esthetic Zone

I would like to thank my parents Dr Gabriele and Dr Herwig Happe

For Marlene and Paula

This book was originally published in German under the title Erfolg mit Implantaten in der ästhetischen Zone: Parodontale, implantologische und restaurative Behandlungsstrategien in 2018 by Quintessenz Verlags-GmbH, Berlin, Germany.

Library of Congress Cataloging-in-Publication Data

Names: Happe, Arndt, editor. | Körner, Gerd, editor.

Title: Techniques for success with implants in the esthetic zone / edited by Arndt Happe and Gerd Körner.

Other titles: Erfolg mit Implantaten in der ästhetischen Zone.English.

Description: Batavia, IL : Quintessence Publishing Co, Inc, [2019] | Includes bibliographical references and index.

Identifiers: LCCN 2019019189 | ISBN 9780867158229 (hardcover) | 9780867159752 (ebook)

Subjects: | MESH: Dental Implantation | Esthetics, Dental

Classification: LCC RK667.I45 | NLM WU 640 | DDC 617.6/93--dc23

LC record available at https://lccn.loc.gov/2019019189

© 2019 Quintessence Publishing Co, Inc

Quintessence Publishing Co, Inc

411 N Raddant Road

Batavia, IL 60510

www.quintpub.com

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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.

Editor: Marieke Zaffron

Design: Sue Zubek

Production: Kaye Clemens and Christine Cianciosi

Printed in China

Contents

Foreword

Preface

Contributors

1Introduction

/ Arndt Happe, Gerd Körner

2Requirements

/ Arndt Happe

3Microsurgery

/ Arndt Happe, Gerd Körner

4Immediate Implant Placement in theEsthetic Zone

/ Arndt Happe, Gerd Körner

5Implant Position, Planning, and Esthetic Analysis

/ Arndt Happe, Christian Coachman, Tal Morr, Vincent Fehmer, Irena Sailer

6Tooth Preservation Versus Extraction and Implant Placement

/ Gerd Körner, Arndt Happe

7Adjacent Implants

/ Tomohiro Ishikawa, Arndt Happe

8Soft Tissue Augmentation

/ Arndt Happe, Gerd Körner

9Bone Augmentation

/ Arndt Happe, Daniel Rothamel, Gerd Körner

10 Implant Exposure Techniques

/ Arndt Happe, Gerd Körner

11 Implant Abutments

/ Anja Zembic, Arndt Happe

12 Superstructure and Peri-Implant/ Restorative Interface

/ Arndt Happe, Pascal Holthaus

13 Complications

/ Arndt Happe, Gerd Körner

14 Complex Cases

/ Tomohiro Ishikawa, Gerd Körner, Arndt Happe

Index

Foreword

There is a common misconception that implant placement and restoration in the esthetic zone is a slam dunk, a more or less simple procedure— especially compared with more demanding full-mouth implant-supported reconstructions. The anterior regions are easy to access for surgery and restoration, hard and soft tissue defects are often limited, and patients are likely younger, meaning greater healing potential. However, this doesn’t mean the esthetic zone is easy to treat— quite the opposite, especially in extenuating circumstances.

Although anterior treatment sites are easier to access, the esthetic outcomes of implant-supported restorations and the adjacent hard and soft tissue framework require the implant positioning to be extremely accurate. Even minor aberrations in implant location and angulation (as well as prosthetic inaccuracies) may have devastating effects. Preoperative bone and tissue defects may indeed be limited in these cases. However, when these defects do occur, they are in the most visible zone, and their treatment therefore requires significantly more attention to detail and a minimally invasive approach, preferably involving microsurgical techniques to restore these defects indiscernibly. In addition, the fact that implant treatment in the esthetic zone is more prevalent in younger patients actually makes these cases significantly more challenging. The procedures themselves may not be more difficult, but the established esthetic and functional outcomes have to be maintained not just for a few years but potentially for decades.

In the past few years alone, we have gained a tremendous amount of new information on how to treat esthetically debilitated patients in need of implant-support restorations. We have learned from the past, when we were often overzealous and too concerned with trying and implementing the latest and greatest techniques—often without sufficient scientific evidence and clinical rigor—rather than truly addressing patients’ needs. Therefore, it is extremely difficult to find a comprehensive up-to-date publication that summarizes the current knowledge and clinical techniques and technologies that provide predictable and long-lasting outcomes. In this book, Drs Happe and Körner, with their team of well-known coauthors, have achieved just that and compiled a unique and exhaustive guide for both the beginning as well as the seasoned surgical and restorative implantologist, explaining and illustrating in a most understandable and beautiful manner how implant treatment should be carried out in the esthetic zone today. From treatment planning and fundamental esthetic guidelines to microsurgical techniques and CAD/CAM technologies, the authors guide the reader through current surgical and restorative principles and techniques, ultimately leading up to more complex and challenging implant-supported restorations in the esthetic zone. The thorough list of cited scientific publications exemplifies the evidence-based approach that was chosen to compile the information and select the most appropriate techniques and technologies.

I have been a great admirer of Dr Happe’s scientific contributions, deep knowledge, and clinical skills, wonderfully compiled in this book. The comprehensiveness, scientific diligence, and clinical excellence displayed will make this title an indispensable guide for any dentist with ambitions for excellence in implant dentistry. Congratulations to the authors for creating this state-of-the-art piece of literature and to the reader who, without a doubt, will greatly enjoy the journey mapped out by Dr Happe and his coauthors.

Markus B. Blatz, DMD, PhD

Chairman and Assistant Dean for Digital Innovation Department of Preventive and Restorative Sciences University of Pennsylvania School of Dental Medicine

Preface

If there’s a book that you want to read, but it hasn’t been written yet, then you must be the one to write it.

TONI MORRISON

Since I started placing implants as part of my oral surgery training in the mid-1990s, I have been especially interested in attempting to copy nature as perfectly as possible. Anyone familiar with the subject will appreciate that this has led to some frustrating experiences, especially if you set a high esthetic standard. I quickly found that good results cannot be achieved without taking into consideration the disciplines of periodontology as well as restorative and esthetic dentistry, and so I attended conferences and courses on these subjects. The problem is that a whole universe of information opens up as soon as you start dedicating yourself more to a discipline. Furthermore, you realize that other specialties such as orthodontics, function, and dental technology are also extremely important and must be incorporated, which means you can feel rather overwhelmed in the beginning.

Over time, however, you gain experience and are better able to prioritize the wealth of information and assess the clinical relevance of the different techniques for yourself. This gives rise to certainty, professionalism, and practiced expertise. However, it is not an easy path, and I thank all my readers and mentors for their invaluable support and confidence in me. We often speak in an abstract way about a learning curve and readily forget that this is underpinned not only by successes but obviously by failures as well. Failures with implants in the esthetic zone can be extremely frustrating, expensive, and painful for everyone involved.

As a young dental practitioner, I would have greatly appreciated a book devoted specifically to the subject of implant therapy in the esthetic zone—and this was precisely our motivation for producing this title. When Dr Körner and I decided to write it, there were hardly any reference books that dealt specifically with implants in the esthetically sensitive area. Yet, while we were working on the book, several publications by reputable authors appeared that handled exactly this subject—or at least touched on it in one or more chapters. As a consequence, we asked ourselves whether it really made sense to continue working on the project. Naturally, we looked at these works with enormous interest. Each of these books enthused and intrigued us in their own particular way. Nevertheless, it seemed to us that the kind of book we had in mind might be an appropriate addition to the range of existing literature in that it would also incorporate related areas of dentistry. After all, every book reflects the experiences and personality of the author or authors in a very specific way.

I am therefore delighted that we managed to attract fascinating contributors, some of whom were already friends, who agreed to provide their unique expertise and have enormously enhanced the book. With this text, we would like to invite all interested colleagues to engage with our understanding and our philosophy of periodontology, implant therapy, and restorative dentistry but also with our approaches to implant therapy in the esthetic zone. We hope our passion and enjoyment of the work will light a spark in our readers.

Arndt Happe

Contributors

Christian Coachman, DDS, CDT

Founder

Digital Smile Design

São Paulo, Brazil

Vincent Fehmer, MDT

Division of Fixed Prosthodontics and

Biomaterials

Clinic of Dental Medicine

University of Geneva

Geneva, Switzerland

Pascal Holthaus, ZTM

Master Dental Technologist

Münster, Germany

Tomohiro Ishikawa, DDS

Private Practice

Hamamatsu, Japan

Tal Morr, DMD , MSD

Private Practice Limited to

Prosthodontics

Miami, Florida

Daniel Rothamel, MD , DMD , PHD

Professor

Department of Maxillofacial and

Plastic Surgery

University Hospital of Düsseldorf

Düsseldorf, Germany

Head of the Division of Maxillofacial

Surgery

Protestant Hospital Bethesda

Mönchengladbach, Germany

Irena Sailer, Prof Dr Med Dent

Head

Division of Fixed Prosthodontics

and Biomaterials

Clinic of Dental Medicine

University of Geneva

Geneva, Switzerland

Anja Zembic, PD, DMD

Consultant

Department of Fixed and Removable

Prosthodontics

University of Zürich

Zürich, Switzerland

Assessment of the esthetic quality of implant treatment has long been ignored in academia. The traditional way to evaluate the success of implants has been to document survival rates, but these only describe whether or not an implant remains functional in the oral cavity. Factors such as clinical immobility and minimal crestal bone level change in defined periods of time have been accepted as measures of osseointegration and consequently of implant success. 1 However, individual criteria for achieving an esthetic appearance in the dentofacial area have been proposed by several authors in the dentistry literature, systematized, and discussed with particular regard to implant treatment. 2–8

From the patient’s point of view, the appearance of the peri-implant soft tissue and the prosthetic superstructures is a very important criterion for successful treatment with implants (Fig 1-1). In 2003, Vermylen et al8 published a study on patient satisfaction with single-tooth implant restorations and stressed that an esthetically satisfactory outcome was a principal concern of patients receiving this type of treatment.

Fig 1-1 / While the implants at the maxillary left lateral incisor and canine sites have been functioning for several years, the result is not a success for the patient because the esthetics are so poor.

In ancient Greece, Plato and Aristotle debated the subject of beauty and esthetics and focused on symmetry in this context. Yet how much symmetry or asymmetry is actually perceived? In 2006, Kokich and Kokich9 examined this topic and compared the esthetic perception of dental deviations among laypeople, dentists, and orthodontists. For this purpose, the smiles of seven women were deliberately manipulated using an image-processing program. Minimal changes were made to crown length, crown width, midline deviation, diastema, papilla height, and the relationship of the mucosa to the lips. The images were then assessed by orthodontists, dentists, and laypeople. It emerged that the orthodontists’ assessment of the dental condition was more critical than that of the dentists and laypeople. All three groups were able to identify unilateral discrepancies in crown width of 2 mm. A unilateral alteration of the gingival margin at a central incisor was recognized by trained dentists when the discrepancy was only 0.5 mm. Laypeople did not notice this change until the difference was 1.5 mm. None of the study groups classified a diastema as unattractive. A unilateral reduction of papilla height was judged less attractive than the same change bilaterally. Orthodontists as well as laypeople rated gingival exposure of more than 3 mm as unattractive.9

Gehrke et al10 conducted a similar study to investigate the influence of papilla length and position of interproximal contact in symmetric and asymmetric situations, comparing the esthetic sensitivity of dentists and laypeople. Starting from a reference image of an anterior dentition that had been digitally idealized, further image processing was carried out to make changes to papilla length and position of the coronal contact point. The digitally manipulated photographs of the anterior dentition were assessed by 105 dental practitioners and 106 laypeople using a questionnaire, and these questionnaires were then analyzed. The authors concluded that the phenomenon of papillary loss associated with the black triangle in the midline was recognized early by laypeople and dentists alike but judged differently in terms of its esthetic impact. Laypeople tolerated the gradual loss of the papilla, provided the remaining interproximal space was completely filled with mucosa due to lengthening of the contact point, thus avoiding a black triangle. Clinicians were significantly more critical in their assessment of asymmetric changes to contact point or papillary length.

In 2004, Belser et al11 criticized the fact that the appearance of implant prosthetic restorations had been neglected in clinical trials and, in their review article on the outcome of anterior implant restorations, concluded that although the use of dental implants in the esthetic zone is well-documented in the literature . . . most of these studies do not include well-defined esthetic parameters.11 This indicates that the esthetic outcome is for the most part poorly documented in scientific studies and is not a criterion of success.

Dental Scores

Various measurable criteria have been sought in dentistry to provide an objective method of addressing this esthetic deficit. In 2005, Meijer et al12 proposed a white esthetic score (WES) to assess the esthetic result of implant restorations. This index was intended to evaluate and document the appearance of crown and soft tissue based on nine parameters. At the same time, Fürhauser et al13 published an index designed solely to assess the peri-implant soft tissue, known as the pink esthetic score (PES) (Fig 1-2). This involves evaluating seven parameters that describe the soft tissue situation and rating them from 0 to 2 so that a maximum score of 14 points can be achieved. In 2009, Belser et al14 proposed their own simplified index that assesses both the soft tissue and the prosthetic superstructure. Their combined PES/ WES score includes five parameters each for crown and peri-implant soft tissue, allowing a maximum score of 10.

Fig 1-2 / Pink esthetic score: index for assessment of peri-implant soft tissue according to Fürhauser et al.13

Patient-Related Factors

It is currently a matter of course for the diagnostic assessment of new patients to include some form of screening to check for various diseases. For instance, there is the periodontal screening index (PSI) for identifying or excluding periodontitis, and temporomandibular screening to evaluate the situation of the temporomandibular joints and involved musculature has also been proposed.15 However, it makes sense for patients to also be screened for esthetic risk factors prior to implantology treatment so that at-risk patients can be identified. One classification for risk assessment of implant treatment that has become established internationally is known as the SAC classification, which divides cases into straightforward, advanced, and complex.16

Lip dynamics

The smile line naturally plays a role in this risk assessment. According to Fradeani,17 a low smile line reveals a maximum of 75% of the maxillary anterior teeth, a medium smile line reveals 75% to 100% of the maxillary anterior teeth plus the papillary apices, and a high smile line exposes 100% of the maxillary anterior teeth plus the facial soft tissues. About 20% of people have a low smile line, 70% have a medium smile line, and 10% have a high smile line. Women have a greater tendency toward high smile lines.18 Because patients with a high smile line expose their facial soft tissue, recessions or other esthetically problematic alterations in this area are instantly visible, whereas they remain unnoticed in patients with a low smile line (Fig 1-3).

Fig 1-3 / A patient with a high smile line exposes the esthetically and functionally inadequate peri-implant soft tissue situation in the region of the maxillary central incisors.

Tissue phenotype

Another typical patient-related factor is the periodontal tissue phenotype, also known as the periodontal morphotype or periodontal biotype. According to Müller et al,19 the thickness of marginal periodontal tissue (masticatory mucosa) is less than 1 mm in roughly 75% of patients. Only about 25% have a tissue thickness of more than 1 mm. Kois4 and Kan et al20 postulated that the different tissue types also react differently to an iatrogenic or inflammatory trauma, which therefore has an influence on the predictability of treatment protocols. Clinical experience shows that thin tissue tends to react to surgical trauma with scarring and recession with more frequency than does thick, fibrous soft tissue.

Kan et al20 showed in a clinical trial that the dimension of the peri-implant tissue around single-tooth implants (eg, the tissue thickness in the interproximal papillary area) is larger in patients with thick biotypes, thereby influencing the esthetic appearance. Regarding immediate implant placement, patients with a thin periodontal biotype clearly have a stronger tendency to severe recession than patients with a thick biotype.21

As a rule, it is not realistic to measure the thickness of the tissue type directly. In clinical practice, this measurement is instead based on the transparency of the periodontal probe through the gingival margin (Fig 1-4a). De Rouck et al22 proposed this method in 2009 and demonstrated a strong correlation with direct measurement in 100 patients. In 2010, Kan et al23 showed in a prospective clinical trial that visual determination of the biotype alone, without the aid of a periodontal probe, is not a reliable method. Tissue thickness also has a considerable influence when selecting restorative materials (see chapter 11).

Fig 1-4 / (a) The biotype can be reliably determined clinically with the aid of a periodontal probe. Two different illustrative tissue types: (b) thick biotype with tough, fibrous tissue and flat papillary contour (scalloping); (c) thin biotype with delicate, transparent tissue and high papillary contour.

Interdental papillae and scalloping

The interdental papillae or so-called scalloping play an important role in all of the scores used to assess the peri-implant soft tissue. Scalloping describes how great the difference in level is between the facial gingival margin and the apex of the papilla and therefore how much the gingival contour undulates. In implantology, flat and wide papillae (Fig 1-4b) are easier to reconstruct than high and narrow papillae4 (Fig 1-4c). Jemt24 proposed a papilla index to assess and systematize the papillary situation:

•Score 0: No papilla present

•Score 1: Less than half of the embrasure filled

•Score 2: Half or more of the embrasure filled

•Score 3: All of the embrasure filled (ie, optimal papilla)

•Score 4: Hyperplastic papilla

In 2001, Choquet et al25 reported that reconstruction of papillae in single-tooth implant restorations is highly dependent on the vertical location of the peri-implant bone and can only be performed predictably if the distance between the contact point of the crowns and the bone is 5 mm or less. Kan et al20 also showed that the tissue height in the area of the papillae is highly dependent on the attachment of adjacent teeth in the case of single-tooth implants; they additionally investigated the influence of the individual tissue phenotype. It emerged that thick tissue phenotypes are likely to have greater tissue height than thin phenotypes. As a result of these interdependences, loss of attachment at adjacent teeth means significant limitations for peri-implant soft tissue. As the foundation, bone codetermines the vertical position of the soft tissue. Therefore, a compromised bony situation that cannot be surgically remedied and affects adjacent teeth will always lead to soft tissue compromise later on. For the most part, these are local prognostic factors.

Predictable reconstruction of a papilla is particularly problematic between adjacent implants,26 especially if three-dimensional (3D) bone augmentation measures are required.27 While crown shape and localization of the contact point also influence the esthetic prognosis of implant restorations, lack of an interdental papilla often spells esthetic failure. Whereas the lack of this papilla can be concealed by a long contact surface in the case of rectangular teeth, this is not possible with triangular teeth and quickly leads to a black triangle in this area.4

Biologic Factors

An understanding of biologic principles with respect to peri-implant tissues is essential when planning for esthetic implant restorations (Fig 1-5). These principles are primarily patient independent. For instance, consider postrestorative remodeling. After reopening of two-part, two-stage implant systems, a biologic width is established around implants in the same way as the biologic width of natural teeth.28,29 This means that the crestal bone is positioned 1.3 to 2.6 mm apical to the interface or the microgap between implant and abutment.30,31 The supporting bone, which ultimately determines the position of the soft tissue, therefore retracts. This can lead buccally to recessions and interproximally to insufficient papilla height Figs 1-6a to 1-6f).26 The latter effect usually does not occur with single-tooth implants because the attachment of adjacent teeth determines papilla height. However, it is a major problem with adjacent implants and makes the reconstruction of papillae between adjacent implants highly unpredictable Figs 1-6g to 1-6j) andFig 1-7).26 These circumstances and their influence on esthetics were described graphically by Grunder et al26 as early as 2005 and motivated the use of platform switching to exert a positive effect on the peri-implant bone situation. As a result, components reduced in diameter came to be used to move the microgap away from the bone in a central direction (see Fig 1-5b).

Fig 1-5 / (a) Unlike natural teeth, implants have no attachment: The collagen fibers of the connective tissue do not integrate with the implant, and no supracrestal fibrous tissue exists. Because the implant has no periodontal space, its vessels are absent, and the peri-implant tissue is poorer in blood vessels. Then there is the added influence of the microgap. All of these circumstances make it difficult to reconstruct soft tissues and papillae around implants. (b) Comparison of structures around implants with non-platform-switched connection (left) and platform switching (right).

Fig 1-6 / (a and b) Anatomy around non-platform-switched implants. (c and d) Excessively large diameter and malpositioning distally lead to loss of papilla. (e and f) Excessively large diameter and malpositioning buccally lead to recession. (g and h) Recommended distances for adjacent implants. (i and j) Adjacent implants placed too close together lead to loss of papilla. (Adapted with permission from Grunder et al.26)

Fig 1-7 / (a) Implant design with smooth (ie, machined) 1.4- mm shoulder. (b) All-ceramic restorations after full-mouth reconstruction, including implants placed at the maxillary right lateral incisor and canine sites and the mandibular right canine site. The interproximal soft tissue between the maxillary lateral incisor and canine is deficient. (Laboratory work performed by A. Nolte.)

Loss of attachment to adjacent teeth poses another limitation. Here again bone height or attachment level determines the expected soft tissue height, which can cause interproximal deficits if there is preexisting periodontal damage (Fig 1-8). The soft tissue situation at the adjacent teeth can only rarely be improved with considerable time and effort (Figs 1-9 and 1-10).

Fig 1-8 / (a) Single-tooth gap at the maxillary left central incisor with adverse preoperative situation due to 3D ridge defect, scarring, triangular tooth shape, and loss of mesial attachment at the rotated maxillary left lateral incisor. (b) Implant restoration 10 years after placement of an all-ceramic crown. (c) The