Clinical and Laboratory Manual of Dental Implant Abutments

Hamid R. Shafie

• Publisher: Wiley-Blackwell
• Year: 2014
• ISBN:
  9781118928530
• Edition: 1
• Topic: Medicine
• Subtopic: Dentistry

To fulfill the vision for his latest book, Dr. Hamid Shafie compiled technical information from a vast variety of sources, including implant manufacturers and designers, master dental technicians, implant researchers, and expert clinicians leading the field of implant dentistry worldwide. He and his expert contributors meticulously assembled each chapter to include only the most relevant and up-to-date content and procedures in a concise and simple format.

Dr. Shafie follows the same easy-to-read, easy-to-understand format as his best-selling textbook Clinical and Laboratory Manual of Implant Overdentures. Starting with the material science behind implant abutments, the text then describes all of the relevant abutment solutions, providing a step-by-step guide to design and manufacturing of the CAD/CAM abutments and explaining how to adjust prefabricated abutments and one-piece titanium and zirconia implants. In addition to offering the ultimate procedural guide for clinical and laboratory preparation of dental implant abutments, this textbook is filled with useful tips on clinical practice management such as sterilization, instrumentation and trouble-shooting related to implant abutments.

Clinical and Laboratory Manual of Dental Implant Abutments is the only text devoted exclusively to an in-depth look at implant abutments. Every dental implant clinician, technician, student, and implant industry insider needs this vital work in their library.

1
Implant Abutment Materials

Hamid R. Shafie¹ and Bryan A. White²

¹Washington Hospital Center, Department of Oral and Maxillofacial Surgery, Washington, DC; and American Institute of Implant Dentistry, Washington, DC

²Private Practice, Gilbert, AZ

Introduction

A wide variety of abutment materials are available on the dental implant market. A major challenge for clinicians today is understanding the biologic response to each material, as well as the best indication for using each of the different types.

To complicate this problem, there are no well defined and comprehensive sources reviewing the properties associated with abutment materials. This chapter provides relevant information on abutment materials and their soft tissue response.

Mucosal Seal

The mucosal seal surrounding a dental implant abutment is an essential factor in preventing bacterial penetration into the crestal bone and around the implant neck. In order to understand the soft tissue response, it is important to be familiar with the anatomy of the mucosal seal.

Natural Dentition

The periodontal soft tissue is an important factor in a person's natural protection against periodontal disease. The biologic width is the depth of soft tissue below the sulcus in the natural dentition. It consists of a junctional epithelium and connective tissue layer. The junctional epithelium ranges from 1 to 2 mm wide followed apically by a 1 mm layer of connective tissue. The alveolar bone lies just below this connective tissue.

In the natural dentition, this zone has been proven to be essential for protecting the periodontium from plaque and bacteria penetration into the oral cavity. The junctional epithelium attaches to the teeth with a hemidesmisomal attachment, providing a shield against bacteria. The connective tissue layer contains collagen fibers that insert into the teeth and cementum perpendicularly to the tooth. These fibers provide additional reinforcement against an apically migrating junctional epithelium caused by periodontal disease.

Peri-implant Mucosal Seal

A mucosal seal surrounding dental implants is also essential in avoiding peri-implantitis. The biologic width surrounding dental implants also contains a junctional epithelium, followed apically by a connective tissue layer. As in the natural dentition, the coronal portion of the biologic width contains the junctional epithelium. In 1984, Gould and colleagues demonstrated that this junctional epithelium attaches to the titanium surface in a similar manner to the natural dentition, with hemidesmosomes. A connective tissue attachment can be found further apically. Buser et al. (1992) described this attachment as being rich in collagen fibers but sparse in cells or resembling scar tissue.

Unlike the natural dentition, in implant abutments the apical connective tissue fibers do not have the same quality of attachments. The natural dentition has dentogingival fibers running perpendicular to the tooth from the bone to the cementum. The connective tissue layer surrounding a dental implant abutment has fibers running in a parallel fashion (Figure 1.1). The only exception to this histology is with Laser-Lok™ abutments which are discussed later in this chapter.

Figure 1.1 Note the perpendicular collagen fibers in the natural dentition (a) and Laser-Lok abutments (c) in comparison to the parallel collagen fibers with other implant abutments (b).

Due to the weakened connective tissue support around implant abutments, the junctional epithelium is believed to be more susceptible to apical migration. In other words, a dental implant is more suscepti­­ble to peri-implantitis than a natural tooth is to periodontitis.

It is important to note that this biologic width or “peri-implant seal” protects the implant against peri-implantitis and provides an esthetic result. When considering which abutment type to use one should consider how well the abutment forms and maintains this mucosal seal.

Pellicle, Biofilm, and Periodontal Disease

One of the key factors in selecting an abutment material is its hygienic property. To review the importance of hygiene it is important to understand pellicle formation, subsequent biofilm production, and the pathway of peri-implantitis development.

Pellicle

The process of plaque formation begins with glyco­proteins attaching to the surface of the enamel or an abutment, creating a thin layer called the pellicle. Although this layer by itself is harmless, it provides a framework for bacteria to adhere to.

Biofilm

A biofilm is an aggregation of multiple organisms coexisting together. Initially, Gram-positive aerobic cocci adhere to this thin glycoprotein layer or pellicle. As these bacteria multiply, the bacterial colonies multiply creating a more anaerobic environment. This anaerobic environment then permits more harmful Gram-negative rods to collect within the biofilm. The biofilm creates an acidic environment that contributes to dental caries but, more relevant to the topic at hand, the biofilm also contributes to periodontal disease.

Periodontal Disease in the Natural Dentition

Periodontal disease is caused by the biofilm, which destroys the periodontium and causes loss of the alveolar bone and inflammation of the periodontal tissues. This is not a novel development – the landmark paper by Page and Schroeder outlined this process of periodontal disease back in 1976.

Peri-implantitis

As in the natural dentition, development of the pellicle and biofilm and subsequent inflammation also occurs with dental implants. This process can cause the potential for apical migration of the peri-implant seal and bone loss. The process of peri-implantitis is more common with dental implants than periodontal disease is with natural dentition. This is because the peri-implant mucosal seal is not as effective (except in the case of Laser-Lok abutments) as the mucosal seal surroun...

Table of contents

• Cover
• Table of Contents
• Title page
• Copyright page
• List of Contributors
• Forewords
• Preface
• Dedications
• 1: Implant Abutment Materials
• 2: General Information about Implant Abutments
• 3: Retaining Abutment Screws
• 4: Different Implant–Abutment Connections
• 5: Prefabricated Implant Abutments
• 6: Use of CAD/CAM Technology in Custom Abutment Manufacturing
• 7: Relationship between Abutment Geometry and Peri-implant Tissue in Esthetic Zone Cases
• 8: Instrumentation for Abutment Modification and Guidelines for their Use
• 9: Abutment Preparation Techniques for One-Piece Titanium and Zirconia Implants
• 10: Cleaning, Disinfection, and Sterilization Techniques for Implant Abutments
• Index
• End User License Agreement