Removable Partial Dentures : A Practitioners’ Manual

This clinical guide, now in an extensively revised second edition, describes the latest developments in planning, materials, and techniques for successful fabrication of removable partial dentures (RPDs). The fabrication of conventional and digital RPDs are demonstrated in a simple and easy-to-understand format, with the aid of numerous color figures and video clips with scientific support on each page. Care has been taken to provide reliable guidance on all aspects of clinical practice relating to RPDs. Readers will find information on decision-making regarding treatment options, clasp-retained RPDs and esthetic solutions, attachments and double crown systems in RPDs, implant-assisted RPDs, maintenance and post-insertion problems for all types of RPDs, the role of RPDs in the management of temporomandibular disorders and the treatment of maxillofacial defects, the re-establishment of occlusal vertical dimension and maximal intercuspation, the rules for disinfection in prosthodontic practice. Foreword Preface and Acknowledgments Preface and Acknowledgments to the First Edition Contents Part I: Introduction to Removable Partial Dentures 1: Current Status on Partial Edentulism and Removable Partial Dentures Further Reading 2: The Effects of Partial Edentulism on the Stomatognathic System and General Health 2.1 Definitions 2.2 Consequences of Tooth Loss Further Reading 3: Classification of Partially Edentulous Arches 3.1 Kennedy Classification 3.1.1 Applegate’s Modification (Kennedy-Applegate Classification System) 3.1.2 Applegate’s Rules 3.2 Implant-Corrected Kennedy Classification System Further Reading Part II: Treatment Planning, Mouth Preparation and Impression Procedures 4: Biomechanics of Removable Partial Dentures 4.1 Definitions 4.2 Understanding Biomechanical Aspects 4.2.1 Rotational Movement 4.2.1.1 Rotational Movement in the Sagittal Plane Around the Horizontal Fulcrum Line 4.2.1.2 Rotational Movement in the Frontal Plane Around the Anteroposterior Horizontal Fulcrum Line 4.2.1.3 Rotational Movement in the Horizontal Plane around the Vertical Fulcrum Line 4.2.2 Biomechanical Design Principles 4.2.2.1 The Inclined Plane 4.2.2.2 The Lever 4.2.2.3 Mechanical Advantage 4.3 The Displacement of the Removable Partial Denture 4.3.1 Movement Toward the Tissue 4.3.2 Movement Away from the Tissue 4.4 Factors that Are Related to the Force Transfer to the Abutment Teeth and the Residual Ridges 4.4.1 The Residual Ridge Support 4.4.2 The Length of the Edentulous Span 4.4.3 The Periodontal Support of the Abutment Teeth 4.4.4 The Design of the Removable Partial Denture 4.4.5 The Design of the Direct Retainer 4.4.6 The Antagonist Dentition Further Reading 5: Diagnosis and Treatment Planning in Partially Edentulous Patients 5.1 Definitions 5.2 Diagnostic Casts and Occlusal Analysis 5.2.1 The Importance of Diagnostic Casts 5.2.2 The Impression and Casts for Diagnostic Models 5.2.3 Using the Diagnostic Casts for Decision Making 5.2.3.1 Periodontal Status 5.2.3.2 Coronal Status 5.2.3.3 Analysis of the Existing Occlusion 5.2.3.4 Deciding the Type of the Prosthesis Classification System for Partial Edentulism Location and Extent of the Edentulous Areas Condition of the Abutment Teeth Occlusal Scheme Residual Ridge Characteristics Removable Partial Denture Indications Shortened Dental Arch Concept 5.2.3.5 Using the Diagnostic Casts for Pretreatment Indications of Occlusal Equilibration The Rules of Occlusal Equilibration Maximal Intercuspal Position-Centric Relation Adjustments Eccentric Adjustments Further Reading 6: Preparation of the Mouth for Removable Partial Dentures 6.1 The Importance of Preprosthetic Preparations 6.2 Periodontal Preparation 6.2.1 Oral Hygiene Motivation and Ensuring Hygiene Ability 6.2.2 Scaling and Root Planing (SRP) 6.2.3 Respecting the Biological Width and Surgical Crown Lengthening 6.2.4 The Importance of Keratinized Gingiva and Free Gingival Grafts 6.3 Oral Surgical Interventions 6.3.1 Preparation of the Bony Base 6.3.2 Soft Tissue Interventions 6.3.3 Removal of Teeth or Tooth Remnants 6.4 Restorative Approach: Fillings and Root Canal Treatment 6.5 Preprosthetic Soft Tissue Conditioning Procedures 6.6 Orthodontic Preparation Further Reading 7: Preparation of the Abutment Teeth for Removable Partial Dentures 7.1 Definitions 7.2 Relationship of Guide Surface and Guide Plate 7.3 Preparation of Rest Seats 7.3.1 Forming of the Retentive Area 7.4 Crowning the Supporting Tooth/Teeth Further Reading 8: Impression Materials and Procedures for Removable Partial Dentures 8.1 Definitions 8.2 Material and Tray Selection for Preliminary Impressions 8.3 Final Impressions 8.3.1 Tray Selection for Single-Step Final Impressions 8.3.2 Impression Materials for Single-Step Final Impressions 8.4 Handling the Impression 8.5 Functional Impressions 8.5.1 The Altered Cast and Its Modifications 8.5.2 Single Tray Functional Impressions 8.6 Impressions for Relining and Rebasing Further Reading Part III: Clasp Retained Removable Partial Dentures 9: Major and Minor Connectors 9.1 Definitions 9.2 Major Connectors 9.2.1 General Aspects of Major Connectors 9.2.2 Maxillary Major Connectors 9.2.3 Mandibular Major Connectors 9.3 Minor Connectors 9.3.1 General Aspects of Minor Connectors 9.3.2 Types of Minor Connectors Further Reading 10: Rests and Rest Seats 10.1 Definitions 10.2 Functions of the Rests 10.3 Forms of Rest and Rest Seat Preparations 10.3.1 Occlusal Rests 10.3.2 Lingual (Cingulum) Rests 10.3.3 Incisal Rests Further Reading 11: Direct and Indirect Retainers 11.1 Definitions 11.2 Direct Retainers 11.2.1 Retentive Clasp Assemblies 11.2.1.1 Retention 11.2.1.2 Support 11.2.1.3 Stability 11.2.1.4 Reciprocation 11.2.1.5 Encirclement 11.2.1.6 Passivity 11.2.2 Factors Affecting the Amount of Retention of a Clasp Assembly 11.2.3 Types of Clasp Assemblies 11.2.3.1 Circumferential (Suprabulge) Clasps 11.2.3.2 Bar (Infrabulge, Roach) Clasps 11.2.4 Stress-Controlling Clasp Design for the Distal Extension Removable Partial Dentures 11.2.4.1 RPI Clasp Design 11.2.4.2 RPA Clasp Design 11.2.4.3 Combination Clasp 11.2.4.4 Rarely Used Infrabulge Clasps 11.3 Indirect Retainers Further Reading 12: Esthetic Solutions for Removable Partial Dentures 12.1 Definitions 12.2 Non-metal Clasp Dentures 12.2.1 General Advantages of Non-metal Clasp Dentures and Thermoplastic Resin Materials 12.2.2 General Disadvantages of Non-metal Clasp Dentures and Thermoplastic Resin Materials 12.2.3 The Basic Principles for Clinical Use of Non-metal Clasp Dentures with Different Thermoplastic Resin Materials 12.3 Rotational Path Removable Partial Dentures 12.3.1 Advantages of the Rotational Path Removable Partial Denture Design 12.3.2 Disadvantages of the Rotational Path Removable Partial Denture Design 12.3.3 Steps of Clinical and Surveying Procedures Further Reading 13: Establishing Occlusal Relationships 13.1 Definitions 13.2 Deciding the Type of Horizontal Relation 13.2.1 Using the Maximal Intercuspal Position as a Reference 13.2.2 Using the Centric Relation as a Reference 13.2.3 Exceptional Cases in Using Maximal Intercuspal position/ Centric Relation as a Reference 13.3 Deciding the Type of Base Plate 13.3.1 Using a Base Plate (or Metal Framework) and Occlusion Rims to Record Horizontal Jaw Relations 13.3.2 Using Check-Bite Method to Record Horizontal Jaw Relations 13.4 Articulators 13.4.1 Using Face-Bow 13.4.2 Important Aspects of Articulator Selection 13.4.3 Properties of a Suitable Articulator 13.5 Clinical Procedure Further Reading 14: Surveying and Laboratory Procedures 14.1 Definitions 14.2 Surveying 14.2.1 Structural Units of a Surveyor 14.2.2 Objective of Surveying 14.2.3 Surveying: The Procedure 14.2.3.1 Systematic Steps of Surveying 14.2.3.2 Tripoding 14.2.3.3 Evaluation of Potential Abutment Teeth Guiding Planes/Guiding Plates Retention Reciprocation 14.2.3.4 Grinding the Diagnostic Cast 14.3 Laboratory Procedures 14.3.1 Final Casts, Mounting in the Articulator and Diagnostic Wax-up 14.3.2 Model Analysis: Mounting of Posterior Teeth 14.3.2.1 Occlusion: Sagittal Stability 14.3.2.2 Occlusion –Transversal Stability 14.3.3 Try-in and Preparation for the Cast Metal Frame 14.3.3.1 Planning 14.3.3.2 The Bios and the Ney Clasp Systems 14.3.3.3 Construction of the Metal Framework Further Reading 15: Initial Placement and Adjustments 15.1 Definitions 15.2 The Timing of Delivery Appointment 15.3 The Goals of Delivery Appointment 15.3.1 Making the Insertion of the Removable Partial Denture Comfortable By Adjusting the Clasp Arms, Overpressure Points on the Impression Surface and Overextended Borders 15.3.2 Checking the Esthetics of the Prosthesis and Making Individualization By Cosmetic Grinding 15.3.3 Adjusting Centric and Eccentric Occlusion 15.3.4 Instructing the Patient How to Maintain the Prosthesis, the Mouth, and the Remaining Teeth Further Reading Part IV: Advanced Retention and Support Auxiliaries for Removable Partial Dentures 16: Attachments and Double Crown Systems for Removable Partial Dentures 16.1 Definitions 16.2 Classification of Attachments 16.2.1 Classification of Attachments According to Their Function Solid Attachments Resilient Attachments Class 1a Class 1b Class 2 Class 3 Class 4 Class 5 Class 6 16.2.2 Classification of Attachments According to Their Location on Abutment Teeth Intracoronal Attachments Extracoronal Attachments Dalbo S Dalbo Mini Preci-Vertix MK1 Ceka ASC 52 Clinical Procedures of Extracoronal Attachments Stud Attachments Types of Stud Attachments Preci-Clix Swiss Dalbo System Gerber Unit TiSi.snap Locator Clinical Procedures of Stud Attachments Bar Attachments Fundamentals of Bar Designs Hader Bar Dolder Bar Ackermann Bar Clinical Procedures of Bar Attachments 16.3 Double Crown Systems 16.3.1 Telescopic Crowns 16.3.2 Conical Crowns 16.3.3 Double Crowns with Clearance Fit (Marburg Double Crown System) Clinical Procedures of Double Crown Systems Further Reading 17: The Role of the Dental Implant in Removable Partial Dentures 17.1 Dental Implants and Removable Partial Dentures 17.2 Important Hints for Clinicians 17.2.1 Main Indications for IARPDs 17.2.2 Contraindications for IARPDs 17.2.3 Advantages of IARPDs 17.2.4 Disadvantages 17.3 Main Alternatives and Different Treatment Modalities with Dental Implant Use as RPD Support 17.3.1 Edentulism 17.3.2 Kennedy Class I and/or II Situation 17.3.3 Kennedy Class III Situation 17.3.4 Kennedy Class IV Situation 17.4 Useful Facts Concerning Implant-Assisted Removable Partial Dentures 17.4.1 Attachments and Different Strategies 17.4.2 Complications and Maintenance Requirements Further Reading Part V: Digital Workflow of Removable Partial Dentures 18: Data Acquisition and Designing 18.1 Definitions 18.2 Background 18.3 Data Acquisition 18.3.1 Digital Scan 18.3.2 The Advantages of Digital Scan in Removable Partial Denture Manufacturing 18.3.3 The Disadvantages of Digital Scan in Removable Partial Denture Manufacturing 18.3.4 Scanning Strategy 18.3.5 Maxillomandibular Relationship Record 18.4 Design of Digital Removable Partial Dentures Further Reading 19: Manufacturing and Materials 19.1 Definitions 19.2 Manufacturing Techniques 19.2.1 Subtractive Manufacturing 19.2.2 Additive Manufacturing 19.2.2.1 Indirect Additive Manufacturing Techniques 19.2.2.2 Direct Additive Manufacturing Techniques 19.3 The Advantage of Digitally Fabricated Removable Partial Denture Frameworks 19.4 The Disadvantage of Digitally Fabricated Removable Partial Denture Frameworks 19.5 Denture Base and Denture Teeth 19.6 Materials for Digital Removable Partial Dentures Framework 19.6.1 Metal-Based Frameworks 19.6.1.1 Cobalt Chromium 19.6.1.2 Titanium 19.6.2 Metal Free-Based Frameworks 19.6.2.1 Polyaryletherketone Polymers (PAEK) Polyetheretherketone (PEEK) Polyetherketoneketone (PEKK) 19.6.2.2 Polyamide (Nylon) 19.6.2.3 Polyoxymethylene (Acetal Resin) 19.6.2.4 Aryl Ketone Polymer (AKP) 19.6.2.5 Graphene-Based Polymers (GBP) 19.6.2.6 Zirconia Further Reading Part VI: Reestablishing Normal Stomatognathic Function in Partially Edentulous Patients 20: Management of Temporomandibular Disorders in Partially Edentulous Patients 20.1 Definitions 20.2 Relationship Between Partial Edentulism and Temporomandibular Disorders 20.3 Occlusal Splints 20.3.1 How Do Occlusal Splints Rehabilitate Temporomandibular Disorders 20.3.2 Occlusal Splint Design in Partial Edentulism Further Reading 21: Reestablishing Occlusal Vertical Dimension and Maximal Intercuspal Position in Partially Edentulous Patients 21.1 Definitions 21.2 Main Reasons for Decreased Occlusal Vertical Dimension in Dentate Individuals 21.2.1 Tooth Wear 21.2.2 Tooth Loss and Migration of the Teeth and/or Alveolar Process 21.2.3 Congenital and Acquired Anomalies 21.2.4 Severe Dental and Skeletal Malocclusions 21.3 The Advantages and Possible Consequences of Increasing the Occlusal Vertical Dimension 21.4 Determination of New Occlusal Vertical Dimension and Evaluation of the Adaptation Period 21.5 Basic Clinical Steps of Increasing the Occlusal Vertical Dimension 21.6 Overlay Removable Partial Dentures 21.6.1 Advantages of Overlay Removable Partial Dentures 21.6.2 Potential Disadvantages of Overlay Removable Partial Dentures 21.6.3 Occlusal and/or Esthetic Materials for Overlay Removable Partial Dentures 21.6.4 Clinical and Laboratory Procedures for Fabricating an Overlay Removable Partial Denture Further Reading 22: Prosthetic Treatment of Partially Edentulous Maxillofacial Defect Patients 22.1 Definitions 22.2 Etiology of Maxillofacial Defects 22.2.1 Congenital and Development Defects 22.2.2 Acquired Defects 22.3 Pre-surgical and Pre-prosthetic Evaluation 22.4 Maxillary Defects 22.4.1 Classification of Maxillary Defects 22.4.2 Surgical Resection and Reconstruction of Maxilla 22.4.3 Prosthetic Workflow of Maxillary Defects 22.4.3.1 Surgical Obturation 22.4.3.2 Interim Obturation 22.4.3.3 Definitive Obturation 22.5 Mandibular Defects 22.5.1 Classification of Mandibular Defects 22.5.2 Surgical Resection and Reconstruction of Mandible 22.5.3 Prosthetic Workflow of Mandibular Defects Further Reading Part VII: Maintenance and Postinsertion Problems of Removable Partial Dentures and Infection Control in Practice 23: Postinsertion Problems 23.1 Definitions 23.2 Pain and Discomfort Related to Soft Tissues or Remaining Teeth 23.3 Difficulty Seating or Removing the Removable Partial Dentures 23.3.1 Incomplete Seating of a Rest and Clasp Assembly on the Related Abutment 23.3.2 Seating Problems Due to Pronounced Soft Tissue Undercuts 23.3.3 Patient-Related Factors 23.4 Lack of Retention and Stability 23.4.1 Broken Clasps or Loss of the Precision Attachments 23.4.2 Decrease in the Function of the Clasps or Precision Attachments 23.4.3 Overextended or Underextended Denture Bases 23.4.4 Deflective Occlusal Contacts 23.4.5 Loss of the Contact Between the Removable Partial Denture and the Underlying Soft Tissue 23.5 Functional Problems 23.5.1 Gagging 23.5.2 Eating or Chewing Difficulties 23.5.3 Phonetic Problems 23.5.4 Tongue or Cheek Biting 23.5.5 Food Impaction or Collection on the Removable Partial Denture Borders 23.6 Esthetic Problems 23.6.1 Esthetic Zone 23.7 Compromised Periodontal Health and Mucosal Lesions Due to Wearing of Removable Partial Dentures 23.8 Allergic Reactions Further Reading 24: Maintenance 24.1 Definitions 24.2 Relining and Rebasing 24.2.1 Relining Tooth-Supported Removable Partial Dentures 24.2.2 Relining Distal Extension Removable Partial Dentures 24.2.3 Step-by-Step Procedures for Direct or Indirect Relining 24.2.3.1 Direct Relining 24.2.3.2 Indirect Relining 24.3 Repairs 24.3.1 Denture Base Repairs 24.3.2 Repair of Major or Minor Connectors 24.3.2.1 Soldering or Brazing 24.3.2.2 Laser Welding 24.3.2.3 Repair with Splinting Using Metal Conditioners 24.3.3 Repair of the Rests or Direct Retainers 24.3.3.1 Repair with a Wrought Wire Clasp 24.3.3.2 Repair with Soldering a Wrought Wire Clasp 24.3.3.3 Repair with a Cast Clasp 24.3.3.4 Chairside Repair with a Cast Clasp 24.3.4 Repair of Fractured or Lost Artificial Teeth 24.3.5 Loss of a Natural Tooth Necessitating Its Replacement 24.3.6 Other Repairs 24.3.6.1 Repair of an Abutment 24.3.6.2 Fabricating a New Precision Attachment Removable Partial Denture Without Changing the Crowns 24.3.6.3 Activating or Changing the Attachment Components of Removable Partial Dentures 24.3.6.4 Maintenance of the Implant-Supported Removable Partial Dentures 24.4 Hygiene Maintenance of the Removable Partial Dentures 24.4.1 Mechanical Hygiene Maintenance 24.4.2 Chemical Hygiene Maintenance Further Reading 25: Disinfection and Hygiene Protocols 25.1 Definitions 25.2 Understanding the Aspects of Sterilization and Disinfection 25.3 Classification of the Disinfectants 25.4 Heat Sterilization in the Dental Office 25.5 Infection Control in Removable Partial Denture Practice 25.5.1 Infection Control for Impressions and Impression Trays 25.5.2 Infection Control for Stone Cast 25.5.3 Infection Control for Removable Partial Denture 25.5.4 Infection Control for Burs and Handpieces 25.5.5 Infection Control for Occlusal Rims and Interocclusal Record Materials 25.5.6 Infection Control for Pumice 25.5.7 Infection Control for Dental Chair 25.5.8 Recommendations for the Cleaning and Decontamination of Clinic Environments Further Reading Index