Techniques for Success With Implants in the Esthetic Zone

Arndt Happe, Gerd Körner

• Publisher: Quintessence Publishing Co, Inc
• Year: 2019
• ISBN:
  9780867159752
• Topic: Medicine
• Subtopic: Dentistry

Implant restoration in the anterior region represents a particular challenge for dentists because even the most functional implant cannot be considered a success if the patient is still unhappy with their smile. Attention must be given to ensuring a high survival rate and a low complication rate, without sacrificing esthetics. In this book, the authors pass on their experience based on well-documented clinical cases and discuss all relevant aspects from the biologic basics and planning to surgery to prosthetic restoration in this challenging area. Modern microsurgical procedures for the augmentation of hard and soft tissue and plastic periodontal surgery are a special focus. Through numerous clinical photographs and schematic drawings, each procedure, whether simple or complex, is reproduced in comprehensive detail.

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 p...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Contents
• Foreword
• Preface
• Contributors
• 1 Introduction / Arndt Happe, Gerd Körner
• 2 Requirements / Arndt Happe
• 3 Microsurgery / Arndt Happe, Gerd Körner
• 4 Immediate Implant Placement in theEsthetic Zone / Arndt Happe, Gerd Körner
• 5 Implant Position, Planning, and Esthetic Analysis / Arndt Happe, Christian Coachman, Tal Morr, Vincent Fehmer, Irena Sailer
• 6 Tooth Preservation Versus Extraction and Implant Placement / Gerd Körner, Arndt Happe
• 7 Adjacent Implants / Tomohiro Ishikawa, Arndt Happe
• 8 Soft Tissue Augmentation / Arndt Happe, Gerd Körner
• 9 Bone 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
• Backcover