Removable Partial Denture Manual Robert W. Loney, DMD, MS 2018 Robert W. Loney, DMD, MS 2018 http://removpros.dentistry.dal.ca Table of Contents Introduction to Removable Partial Dentures .............................................................. 1 A. Definitions ............................................................................................................. 1 B. Treatment Objectives ............................................................................................ 1 C. Alternatives to RPD's (Treatment Options - Important for Informed Consent)........ 1 D. Indications for RPD's .............................................................................................. 2 E. Components of a Partial Denture ........................................................................... 4 F. Classification .......................................................................................................... 5 Applegate's Rules for Applying the Kennedy Classification ........................................ 6 Anatomy for Complete and Removable Partial Dentures .......................................... 7 Irreversible Hydrocolloid Preliminary Impressions ................................................. 12 Selection of a stock tray:........................................................................................... 12 Handling the Material: ............................................................................................... 12 Measuring and Mixing alginate ................................................................................. 12 Making the impression .............................................................................................. 13 Evaluating Irreversible Hydrocolloid Impressions ..................................................... 13 Pouring a Model ....................................................................................................... 13 Two-Pour Technique ................................................................................................ 14 Trimming ................................................................................................................... 15 Surveying, Path of Insertion, Guiding Planes .......................................................... 16 Other Uses of a Surveyor: ........................................................................................ 16 Parts of a Surveyor: .................................................................................................. 17 Selecting the Path of Insertion of a Removable Partial Denture ............................... 18 The Optimal Path of Insertion ................................................................................... 19 Selection and Preparation of Guiding Planes: .......................................................... 22 Suggested Right Handed Operator Positioning ........................................................ 23 (Left Handed [LH] positions in brackets) ................................................................... 23 The Effects of Guiding Planes on Retention and Stability......................................... 23 Alteration of Other Axial Contours ............................................................................ 24 Summary of Removable Partial Denture Abutment Modifications ......................... 26 Rests and Rest Seats ................................................................................................. 27 A. Definitions ........................................................................................................... 27 B. Functions of Rests............................................................................................... 27 C. Preparation of Rest Seats ................................................................................... 28 Suggested Operator Positioning (see previous chapter on guiding planes) ............. 28 D. Rest Seat Form ....................................................................................................... 28 1. Occlusal Rest Seats .................................................................................... 28 Table of Contents - ii 2. Lingual Rest Seats ...................................................................................... 31 Composite Buildups for Cingulum Rests: ................................................. 34 Round Lingual Rest Seat Form ................................................................ 35 3. Incisal Rests................................................................................................. 35 Major Connectors ........................................................................................................ 36 Functions of a Major Connector ................................................................................ 36 Requirements of a Major Connector ......................................................................... 36 I. Mandibular Major Connectors ................................................................................... 37 A. Lingual Bar .................................................................................................. 38 B. Lingual Plate ................................................................................................ 39 C. Continuous Bar Retainer (Kennedy Bar, Double Lingual Bar) ................... 40 D. Labial Bar ................................................................................................... 40 II. Maxillary Major Connectors ...................................................................................... 40 A. Anterior-Posterior Palatal Strap ................................................................... 40 B. Full Palatal Plate ......................................................................................... 41 C. Palatal Strap (or Bar) .................................................................................. 41 D. Anterior Palatal Plate (U-Shaped Or "Horse-Shoe" Palatal Connector) ...... 42 Minor Connectors ....................................................................................................... 43 Functions .................................................................................................................. 43 Basic Types of Minor Connectors: ............................................................................ 43 GridWork Design ....................................................................................................... 46 Direct and Indirect Retainers ..................................................................................... 48 I. Retention............................................................................................................... 48 II. Extra-Coronal Direct Retainers ............................................................................. 48 Requirements of Direct Retainers ............................................................................. 49 Factors affecting the magnitude of retention ............................................................. 49 Direct Retainers For Tooth-Borne RPD’s .................................................................. 51 1. Circumferential (Akers) clasp ....................................................................... 51 2. Ring clasp .................................................................................................... 52 3. Double Embrasure Clasp............................................................................. 53 4. C-Clasp ........................................................................................................ 53 Direct Retainers For Tooth and Tissue Borne RPD's ................................................ 54 1. Bar Clasps ................................................................................................... 55 The R-P-I Clasp ......................................................................................... 56 2. RPA Clasp .................................................................................................. 59 3. Combination Clasp ...................................................................................... 59 The Distal Rest Concept ............................................................................ 59 Direct Retainer Choices .............................................................................................. 61 III. Indirect Retainers .................................................................................................... 62 Table of Contents -iii Denture Bases and Replacement Denture Teeth ..................................................... 65 Functions .................................................................................................................. 65 Materials ................................................................................................................... 65 Flange Extension ............................................................................................. 66 Acrylic Resin Finish Lines ................................................................................ 67 Partial Denture Replacement Teeth ................................................................. 68 Principles of Partial Denture Design ......................................................................... 69 Denture Bases .......................................................................................................... 70 Direct Retainers .......................................................................................................