Implant Placement in Post-Extraction Sites

Treatment Options

Daniel Buser, Daniel Wismeijer, Urs C. Belser, Daniel Buser, Daniel Wismeijer, Urs C. Belser

• Editorial: Quintessence Publishing
• Año: 2019
• ISBN:
  9781850973461
• Edición: 1
• Categoría: Medicine
• Categoría: Dentistry

This third volume of the ITI Treatment Guide series provides clinicians with practical clinical information that will allow them to make evidence-based decisions regarding appropriate implant placement protocol in post-extraction sockets. The book features 15 case presentations illustrating the use of various clinical protocols as well as discussion of the factors influential to treatment outcome and potential complications.Implant dentistry has become a standard option for the rehabilitation of fully and partially edentulous patients. With the ever-increasing number of dentists involved in implant dentistry, it is essential to ensure that their treatment methods follow the highest standard. The ITI Treatment Guide series, a compendium of evidence-based implant-therapy techniques in daily practice, is written by renowned clinicians and provides a comprehensive overview of various therapeutic options. Using an illustrated step-by-step approach, the ITI Treatment Guide shows practitioners how to manage different clinical situations, with the emphasis on sound diagnostics, evidence-based treatment concepts, and predictable treatment outcomes.

1   Introduction

S. Chen, D. Buser

Over the last decade, the evolution of implant dentistry has continued, with significant advances in biomaterials and clinical techniques through ongoing research and development. To a large extent, this evolution has reflected the change in the demographics of individuals going to dental offices for treatment today. While in the past, most patients presented with edentulous spaces, today the majority seek replacement of teeth that require extraction prior to implant placement. In these cases, the clinician must make a very important decision, i.e. to recommend the best time to place an implant after the tooth has been extracted. The clinician must also select the most appropriate biomaterials to be used. The need for functional and esthetic outcomes as well as a desire for reduced treatment times must be weighed carefully against the pretreatment conditions of the site, dimensional changes that will occur following extraction, the predictability of the planned treatment approach, and the related risk of complications.

In August 2003, the ITI met at the Third ITI Consensus Conference to discuss a number of issues in implant dentistry, one of them being the subject of implant placement in post-extraction sites. The proceedings of this conference were published in a supplement to the International Journal of Oral & Maxillofacial Implants in 2004. Four years later, the issue of post-extraction implant placement continues to be of great interest.

In this Treatment Guide, a summary of the findings and consensus statements from the Third ITI Consensus Conference is provided, supplemented by an update of the literature pertaining to post-extraction implants published in the last four years. Based on this evidence, recommendations for the various treatment approaches are provided and supported by detailed case reports.

As with the preceding two volumes of the ITI Treatment Guide, the authors hope that this volume will present a valuable resource to clinicians who in their daily practice must provide predictable treatment for the benefit of their patients.

2 Proceedings of the Third ITI Consensus Conference: Implants in Post-Extraction Sites

The International Team for Implantology (ITI) is an independent academic network that unites professionals from all fields of implant dentistry and related tissue regeneration. It is active in the fields of research, development, and continuing education, and is dedicated to the promotion and spread of knowledge about all aspects of implant dentistry and related tissue regeneration for the benefit of patients. To date, the ITI unites about 5000 Fellows and Members in more than 40 countries.

The ITI regularly draws up and publishes treatment guidelines that are based on comprehensive clinical studies and supported by long-term clinical results. The results of this commitment include, for instance, publications such as the ITI Treatment Guide and the ITI Consensus Papers.

The ITI organizes consensus conferences at five-year intervals to discuss relevant topics in implant dentistry. The first and second ITI Consensus Conferences in 1993 and 1997 (Proceedings of the ITI Consensus Conference 2000) primarily discussed basic surgical and prosthetic issues in implant dentistry.

The third ITI Consensus Conference was convened in 2003. For this conference, the ITI Education Committee decided to focus the discussion on four special topics that had received much attention in recent years, “Implants in Extraction Sockets” (current terminology: post-extraction sites) being one of them (Proceedings of the Third ITI Consensus Conference, International Journal of Oral and Maxillofacial Implants, 2004. Vol 19, Supplement).

The objectives of the ITI Consensus Conference were to review the current literature in peer-reviewed journals and to discuss where sufficient evidence was available for specific clinical procedures and where evidence was lacking.

A working group was elected for the exploration of each topic. Working Group 1,under the leadership of Professor Christoph H. F. Hämmerle, was asked to review relevant literature, focus on, and find consensus relating to implants in post-extraction sites.

The participants of Working Group 1 were:
Gil Alcoforado
Jay R. Beagle
Jean-Pierre Bernard
Stephen T. Chen
Anthony Dickinson
Paul Fugazzotto
Erik Hjørting-Hansen
Louis Antonio Lima
Jan Lindhe
Thomas Oates
Mario Roccuzzo
James Ruskin
Thomas von Arx
Gerhard Wahl
Thomas G. Wilson Jr.

2.1 Consensus Statements and Recommended Clinical Procedures Regarding the Placement of Implants in Post-Extraction Sites

The group was asked to develop evidence-based reviews on topics related to various placement protocols for dental implants. The following material was presented to the group for review and discussion:

• Stephen T. Chen, Thomas G. Wilson Jr., and Christoph H. F. Hämmerle: “Immediate or Early Placement of Implants Following Tooth Extraction: Review of Biologic Basis, Clinical Procedures, and Outcomes” (Chen and coworkers, 2004)

The aim of this article was to review the current literature with regard to survival and success rates, along with the clinical procedures and outcomes associated with immediate and delayed implant placement.

The consensus statements and proposed clinical approaches defined by Working Group 1 on the topic of “Implants in Extraction Sockets”, as listed in Chapters 2.1.1 and 2.1.2 are intended to serve as a guide to clinicians in the diagnosis, treatment planning, and management of patients requiring dental implant therapy.

With the consensus statements as guidelines, it is hoped that clinicians will be better prepared to make informed surgical and prosthodontic treatment decisions to further enhance the quality of care and predictability of treatment outcome for their patients.

2.1.1 Consensus Statements

Socket Healing

Results of clinical, radiologic, and histologic studies indicate that bony healing of extraction sites proceeds with external resorption of the original socket walls and a varying degree of bone fill within the socket.

Bone Regeneration

Studies in humans and animals have demonstrated that at implant sites with a horizontal defect dimension (HDD; i.e. the peri-implant space) of 2 mm or less, spontaneous bone healing and osseointegration of implants with a rough titanium surface takes place.

In sites with HDDs larger than 2 mm and or non-intact socket walls, techniques utilizing barrier membranes and/or membrane-supporting materials have been shown to be effective in regenerating bone and allowing osseointegration.

Although scarce, the majority of the comparative data regarding the success of bone regeneration at peri-implant defects suggests no differences between Type 1, 2, and 3 procedures.

Further comparative analyses of different methods of bone augmentation with regard to successful bone formation and stability over time are required.

Long-term analysis of the stability of the regenerated bone is focused almost exclusively on radiographic assessments of the interproximal bone and implant survival. There is a need for studies to evaluate the fate of the buccal bone plate – whether regenerated or not – over time.

Adjunctive Medication

In most studies reviewed, broad-spectrum systemic antibiotics were used in conjunction with implant placement Type 1, 2, and 3. Controlled studies evaluating the effect of systemic antibiotics on treatment outcomes are needed.

Survival of Implants

The survival rate of immediately placed implants (Type 1) was reported in numerous studies to be similar to that of implants placed into healed ridges (Type 4).

In the few studies available, short-term survival rates of implants placed in conjunction with Type 2 and 3 procedures appear similar to those placed in Type 1 and 4 approaches.

There have been relatively few reports on the subject of Type 2 and 3 implant procedures, and only 2 of them were randomized with respect to timing of placement and augmentation methods used. Longitudinal studies of greater than 3 years’ duration were limited to 2 reports.

There is evidence to suggest that the survival rate for implants placed immediately following extraction of teeth associated with local pathology is similar to that of implants placed into healed ridges. Further controlled studies are required to provide definitive information about the management of these situations.

Esthetic Outcomes

Esthetically pleasing treatment outcomes have received considerable attention in recent years; however, there are no controlled studies available on esthetic treatment outcomes in Type 1, 2, and 3 procedures.

2.1.2 Proposed Clinical Approaches

Patient Assessment

All candidates for extraction-site implants should meet the same general screening criteria as regular implant patients, regardless of the timing of implant placement.

Antibiotics

The literature is inconclusive regarding antibiotic use in conjunction with implant therapy. There is general agreement that the use of antibiotics is advantageous when augmentation procedures are performed.

Tooth Extraction

Extraction techniques that result in minimal trauma to hard and soft tissue should be used. The sectioning of multi-rooted teeth is advised. All granulation tissue should be removed from the socket.

Site Evaluation

Site evaluation is critical to the determination of appropriate treatment modalities. Factors of concern include:

• Overall patient treatment plan
• Esthetic expectations of the patient
• Soft tissue quality, quantity, and morphology
• Bone quality, quantity, and morphology
• Presence of pathology
• Condition of adjacent teeth and supporting structures

Primary Implant Stability

The implant should not be placed at the time of tooth removal if the residual ridge morphology precludes attainment of primary stability of an appropriately sized implant in an ideal restorative position.

Thin Biotype

When treating patients with a thin, scalloped tissue biotype – even those with an intact buccal plate – concomitant augmentation therapies at the time of implant placement (Type 1) are recommended because of the high risk of buccal plate resorption and marginal tissue recession.

If buccal plate integrity is lost, implant placement is not recommended at the time of tooth removal. Rather, augmentation therapy is performed, and a Type 3 or 4 approach is utilized.

Thick Biotype

In cases involving a thicker, less scalloped tissue bio-type with an intact buccal plate, the need for concomitant augmentation therapies at the time of implant placement (Type 1) may be reduced, since thick bio-types have a decreased risk of buccal-plate resorption in comparison with thinner biotypes. As buccal-plate integrity is lost, the need for augmentation therapies increases.

When the buccal plate is compromised, negatively impacting the predictability of treatment outcomes, immediate (Type 1) implant placement is not indicated; rather, a Type 2, 3 or 4 procedure is carried out. When the HDD is greater than 2 mm, concomitant augmentation therapy needs to be performed.

Adjunctive augmentation therapies may be indicated in any of the above situations to optimize esthetic treatment outcome.

Implant Placement

The three-dimensional positioning of the implant should be restoratively driven.

2.1.3 Conclusions

The Third ITI Consensus Conference took place in August 2003. The Consensus Statements phrased by Working Group 1 explored the topic of “Implants in Extraction Sockets” and were based on the body of literature available at that time.

Meanwhile, the topic of “Implants in Extraction Sockets” has been further researched, and additional literature has been published. In addition, new implant surface technologies and their influence on immediate and early placement protocols have been investigated.

Chapter 2.2, “Implants in Post-Extraction Sites – A Literature Update,” and Chapter 3.2, “Advantages and Disadvantages of Treatment Options for Implant Placement in Post-Extraction Sites” recognize the evolution of implant placement protocols, including recent data and literature, in order to give a state-of-the-art overview of implant placement protocols in connection with the clinical implications and applications to be derived from them.

2.2 Implants in Post-Extraction Sites – A Literature Update

S. Chen, D. Buser

2.2.1 Classification for the Timing of Implant Placement After Tooth Extraction

Since the Third ITI Consensus Conference in August 2003, there has been a sustained interest in techniques for placing implants in post-extraction sites. Several randomized controlled clinical studies and a number of prospective and retrospective case series studies have been published to provide additional information regarding the clinical outcomes of this mode of treatment.

A number of descriptive terms have been used to indicate the timing of implant placement after the extraction of teeth. Wilson and Weber (1993) proposed the terms “immediate,” “recent,” “delayed,” and “mature” to describe the timing of implant placement in relation to soft-tissue healing and the predictability of guided bone-regenerative procedures using barrier membranes. In 1999, the terms “delayed” and “late” were used to describe time intervals of 6 to 10 weeks and 6 months or more after extraction, respectively (Mayfield, 1999). More recently, the term “early” implant placement has been used to describe implant placement after initial soft- and hard-tissue healing, but before complete ...