RPD Learning Objectives

How to use this note

Each objective is one bullet, verb-led, and tagged by tier:

🔴 High — high-yield clinical (practical-exam / chairside critical)

🟡 Med — important but second-priority

🟢 Low — background / theoretical / nice-to-know

The Master High-Yield Checklist below aggregates every 🔴 objective across all lectures. Tick items off as you confirm fluency. For deeper context jump to the per-lecture sections (L1–L10).

Master High-Yield Checklist

L1 Introduction to RPD

🔴 Define RPD vs FPD and list indications for each given a clinical scenario
🔴 State Ante’s Law and apply it to decide between fixed bridge and RPD
🔴 Compare chrome vs acrylic dentures (indications, longevity, repairability, vertical-space requirements)
🔴 Justify why distal extension cases contraindicate fixed bridges
🔴 Distinguish indications for an interim vs definitive RPD
🟡 Describe Combination Syndrome (Kelly’s syndrome) — four pathological changes and the two causative scenarios
🟡 List the patient factors that contraindicate fixed restorations (<18 yo, low manual dexterity, long span, excessive bone loss)
🟡 Distinguish treatment “need” from treatment “demand,” especially in elderly patients
🟢 Discuss masticatory function’s link to cognitive decline / dementia risk
🟢 List bone-remodelling phases (immediate 3–6 mo, stabilization 12 mo) and classify congenitally missing teeth (hypodontia / oligodontia / anodontia)
🟢 Cite Australian life-expectancy figures and global tooth-loss trends

L2 Components and Classifications

🔴 Identify the seven RPD components (rest, retentive arm, reciprocal arm, proximal plate, major connector, minor connector, saddle) and the function of each
🔴 Define direct vs indirect retainer and locate each relative to the fulcrum line
🔴 Classify any partially edentulous arch using the four Kennedy classes
🔴 Apply all eight Applegate rules — including “no modifications in Class IV” and the third-/second-molar rules
🔴 Count modifications correctly (one per additional edentulous area, not per missing tooth)
🔴 Distinguish tooth-supported, tooth-and-tissue-supported, and tissue-supported cases and predict prognosis
🔴 Recognise that unilateral-extension framework designs are prohibited (aspiration risk) — must be bilateral
🟡 Justify why ceramic artificial teeth are contraindicated on RPDs
🟡 Explain why Class III has the best biomechanical prognosis
🟡 Describe the biomechanical view (intercalated / levered / combined) and how it predicts force distribution
🟢 List Applegate Classes V and VI and when they’re invoked
🟢 Recite the historical evolution of classification (Cummer, Kennedy, Bailyn, Neurohr)

L3 Rests and Rest Seats

🔴 Differentiate “rest” (RPD component) from “rest seat” (tooth preparation)
🔴 Specify occlusal rest seat dimensions (rounded triangular; B/L = ½ inter-cusp distance; M/D ≥ B/L; concave floor; angulation <90°; thickness 0.5 mm at point and 1.0–1.5 mm at marginal ridge)
🔴 Describe lingual/cingulum rest seat morphology (M/D convex “inverted smile,” B/L concave V, angulation <90°, ≥0.8 mm reduction)
🔴 Explain why preparation is mandatory (without it the lab makes a tall metal contour → high bite; dangerously thin if ground)
🔴 Justify why box-shaped rest seats are contraindicated (concentrate load, prevent rotation, plaque trap)
🔴 Place rests adjacent to edentulous space in Class III, but mesial to the terminal abutment in Class I/II — explain the tipping mechanism
🔴 Position primary (direct) vs secondary (indirect) rests relative to the fulcrum line
🟡 List the two primary and five secondary functions of a rest
🟡 Describe the consequences of placing a rest with no rest seat (lingual sliding, buccal tipping, tissue impingement, mobility — case study)
🟡 Describe incisal rest morphology and when to use it (only when lingual rest impossible; aesthetic + leverage drawbacks)
🟢 Recite the enamel-thickness reference values for max/mand molars and premolars
🟢 Outline a composite-buildup technique for creating a cingulum rest seat (rubber dam, retraction cord, single increment, below opposing contact)

L4 Clasp Assembly

🔴 List the four components of a clasp assembly (rest, retentive arm, reciprocal arm, minor connector)
🔴 Explain the elastic-deformation retention mechanism and the consequence of exceeding the elastic limit
🔴 State the six requirements of every retentive unit (Support, Stabilization, Retention, Reciprocity, Engagement, Passivity) and what each contributes
🔴 Apply the >180° encirclement rule and explain what happens if it’s violated
🔴 Locate the terminal third of the retentive arm in the gingival / middle third (below HOC)
🔴 List the five flexibility factors (length, taper, cross-section, diameter, material) and how each affects clasp behaviour
🔴 Match clasp type to indication: Akers / simple circumferential (standard intercalated); reverse circumferential (tilted abutment); ring (mesiolingually-tipped molar); embrasure (indirect retention between two adjacent teeth); T / modified-T / I-bar (aesthetics); RPI (Kennedy I/II free-end)
🔴 Name the RPI components (Rest, Proximal plate, I-bar) and justify why RPI is contraindicated on canines/incisors (emergence profile)
🔴 Specify guide-plane requirements (parallel, ≥2–3 mm vertical height, prepared with parallel diamond bur — not tapered)
🟡 Explain the infrabulge stress-releasing advantage in free-end saddles
🟡 Compare suprabulge (occlusal approach) vs infrabulge (apical approach) clasps mechanically
🟡 Describe the disadvantages of clasp-retained RPDs (caries, plaque, PDL strain) and the patient-compliance prerequisite (control-phase completion)
🟢 Compare cast gold vs Cr-Co vs wrought-wire alloys for undercut tolerance (0.50, 0.25, 0.75 mm)
🟢 Outline telescopic crown-retained RPDs and when they’re justified
🟢 Discuss aesthetic clasp materials (PEEK, polyacetal, nylon) and current limitations

L5 Major and Minor Connectors

🔴 State the primary functions of a major connector (cross-arch union, force distribution, indirect retention assistance, periodontal preservation)
🔴 Justify why rigidity is non-negotiable and predict the consequences of a flexible connector
🔴 Specify gingival clearance — mandible 3–4 mm, maxilla 5–6 mm — and apply each
🔴 Select the correct maxillary major connector for: small Class III; Class II / Class III with anterior mod; weak periodontium; large palatal torus; nearly edentulous arch with guarded teeth
🔴 Justify why the U-shape (horseshoe) is the worst for rigidity and use it only when forced (large torus extending to soft palate)
🔴 Specify minimum strap width (≥8 mm) and the 90° suture-crossing rule
🔴 Select the correct mandibular major connector for: adequate floor depth (lingual bar); shallow floor / high frenum (lingual plate); lingual tori (sublingual bar); long retroclined anteriors / wide diastemas (avoid cingulum bar); periodontally compromised anteriors needing splinting (lingual plate or double bar)
🔴 State the lingual bar space requirement: 8 mm total = 5 mm bar height + 3 mm clearance from gingival margin
🔴 Explain why mandibular major connectors give NO vertical support (unlike maxilla, which rests on hard palate)
🔴 Differentiate internal (90° butt joint) vs external (beveled) finish lines and what each does for the acrylic
🟡 Describe the function of bead lines (maxilla only), how they’re placed, and the 6 mm fade rule from gingival margins
🟡 State the function of cast stops in Class I/II frameworks (prevent metal lift during acrylic processing)
🟡 Apply minor connector design rules: right-angle to major connector, interdental placement, narrow M/D dimension to spare gingival margin, gridwork covers tuberosity (max) or 2/3 ridge (mand)
🟢 Compare metallic vs acrylic denture-base advantages and disadvantages (thermal conductivity, weight, relinability, fungal risk, micro-porosity)
🟢 List daily denture-cleaning methods and explain why sodium hypochlorite is contraindicated for RPDs (corrodes metal)
🟢 Recite McCracken / GPT-9 textbook definitions of major and minor connectors

L6 Dental Surveyor

🔴 Name the major surveyor components and the function of each (vertical column, horizontal arm, surveying arm, analyzing rod, carbon marker, undercut gauges, surveyor blade, surveying table, mandrel, wax knife)
🔴 Demonstrate correct carbon-marker technique — use the side of the lead, not the tip, to avoid creating a false height of contour
🔴 State the three undercut depths by alloy (CoCr 0.25 mm; cast gold 0.50 mm; stainless wire 0.75 mm) and the consequence of plastic deformation if a CoCr clasp is forced into a 0.75 mm undercut
🔴 Describe the Roach three-point method — perpendicular to a plane defined by mesial marginal ridges of molars + proximal contact between centrals (NOT the incisal edge)
🔴 Describe the Bisector (Roth) technique, what it considers (M-D and B-L inclination), and when it fails (multiple varying inclinations)
🔴 Describe the Applegate technique (best incline placing HOC between gingival and middle thirds) and when to use it
🟡 State the four functions of the surveyor
🟡 Differentiate true vs false height of contour
🟡 Distinguish the three model types (Study, Master, Refractory) and what each is for
🟢 Outline digital surveying with 3Shape CAD
🟢 Outline historical evolution of surveyor design and minor manufacturer-specific component name variations
🟢 Discuss theoretical elasticity moduli of clasp alloys

L7 Survey and Design

🔴 Execute the seven-step surveying sequence: preliminary assessment → POI → HOC → rest position → desired undercut → framework outline → adjust contour / guide planes
🔴 Demonstrate horizontal vs vertical tripoding and explain when each transfers between casts (horizontal transferable; vertical not)
🔴 Place the rest adjacent to edentulous space in Class III but mesial to terminal abutment in Class I/II to control rotation
🔴 Locate the fulcrum line on a cast and place indirect retainers perpendicular and as far from it as possible
🔴 Apply the 3 mm soft-tissue undercut threshold to choose suprabulge (>3 mm) vs infrabulge (≤3 mm) clasp
🔴 Verify that infrabulge clasps need ≥3 mm attached gingivae from free gingival margin to undercut top
🔴 Use a 0.25 mm undercut gauge for CoCr — gauge below HOC, slide upward until contact, mark retentive point
🔴 Apply the universal 3 mm gingival-margin clearance rule for all minor connectors
🔴 Specify guide-plane extent (2/3 intercuspal distance, ≥2/3 crown height, 2–3 mm minimum)
🔴 Recognise when survey-only modification fails and a survey crown is required (severe tilt, missing HOC, no undercut after path optimisation)
🟡 Apply lateral vs A-P tilt (lateral equalises bilateral HOC; A-P establishes guide planes with minimal reduction; over-tilt creates false undercuts)
🟡 Manage path-of-insertion compromises with mandibular tori (forward tilt, lingual plate alternative, surgery) and palatal torus (avoid crossing — horseshoe or posterior strap)
🟡 Decide between enameloplasty (<1 mm overerupted molar) vs full-coverage survey crown (>1 mm)
🟢 Describe wax-block reference for missing landmarks during surveying
🟢 Describe Duralay survey-pin fixation as a repositioning aid
🟢 Recite Type III gypsum study-model specs

L8 Mouth preparation for RPD

🔴 Distinguish the Control phase (perio / endo / restorative / surgery / ortho / occlusal) from the Reconstructive (Biomechanical) phase (rest seats, guide planes, contour) and state why Control must complete first
🔴 Verify Control-phase success by reduced bleeding-on-probing and probing depth (not by tactile cleanliness alone)
🔴 Apply the ferrule rule (360° ideal; partial buccal-lingual may suffice for restorability)
🔴 Apply the rest-in-amalgam rule — ≥1 mm amalgam under and around the seat; if the seat would cross a tooth-restoration interface, replace the restoration first
🔴 Decide endo abutment readiness: recent fill / no radiolucency → wait for bone formation; old fill / radiolucency → percussion test, possibly retreat; partial fill or symptomatic → retreat; OCHWA rule — RCTs done outside OCHWA on a planned abutment should be offered retreatment first (R1 OCHWA guideliens for RPD and endotreated teeth)
🔴 Fabricate a Duralay transfer guide correctly: separator (not Vaseline), ≥5 mm acrylic block, parallel-trim to POI, cement with zinc phosphate (not GIC, so it can be removed)
🔴 Describe two strategies for raising HOC when natural undercut is inadequate (composite addition above retentive area; or buccal/lingual arm swap with path change)
🔴 State the indications for a survey crown vs conservative recontouring
🔴 Recognise occlusal-adjustment vs vertical-dimension-increase scenarios for worn dentitions (cup-shaped lesions = erosion + attrition → consider OVD increase + composite build-ups + crowns)
🟡 Describe orthodontic indications for pre-prosthetic alignment (molar inclination, rotation, anterior migration) and the role of mini-implants for intrusion
🟡 Compare free-hand transfer vs Duralay vs base-plate transfer methods (and the limits of free-hand)
🟡 Compare survey-crown materials (PFM with metal-on-metal at clasp/rest contact vs zirconia / CAD-CAM all-ceramic)
🟢 Describe Essex retainer fabrication for emergency single-tooth replacement
🟢 Describe wax-rim V-notch occlusal-registration technique
🟢 Discuss biological-width and crown-lengthening considerations in severe perio cases

L9 Clinical Sequence

🔴 Sequence the full clinical-laboratory workflow: history → study models + face-bow mounting → diagnostic wax-up → mouth prep → final elastomeric impression → master model + duplication → framework casting → framework try-in → MMR / altered cast → tooth try-in → processing → insertion → review
🔴 Record OVD using freeway space (formula OVD = RVD − freeway, average freeway 3 mm) and verify with closest speaking space (“Mississippi 66”) — and state why closest speaking space is more reliable than freeway
🔴 Use a leaf gauge for centric relation (each leaf 200 µm), avoiding the over-retruded discomfort position; use an anterior jig for TMD symptoms
🔴 Identify the altered cast indication (mandibular Kennedy I / II only — never maxilla, never Class III) and its purpose (functional ridge form under controlled compression)
🔴 Apply the finger-pressure rule during altered-cast and reline impressions: pressure on rests only, never on the free-end saddle
🔴 Assess framework on/off model — passive seating, no rocking, retention/stability, mesh relief adequate, tissue-side smooth (not polished)
🔴 Apply the terminal-third never-adjust rule — only minor connectors, reciprocal arms, and the proximal 2/3 of the retentive arm are adjustable
🔴 Define the neutral zone (tongue forces = circumoral musculature forces) and explain consequences of placing teeth outside it (instability, soft-tissue trauma)
🔴 Manage insertion defects — voids/porosity → return to lab; nodules / sharp projections → adjust chairside; overextensions → trim; check with fit checker spray or light-body PVS
🔴 Reline using PVS or ZOE with the same rests-only finger-pressure protocol, then take a pickup impression with alginate (after re-recording the bite)
🟡 Verify framework occlusion with shim stock and articulating paper (no interference, lateral excursion clean)
🟡 Use the diagnostic wax-up to plan tooth position, identify needed survey crowns, and predict final aesthetics
🟡 Distinguish “fits cast but not mouth” (inaccurate cast → new impression needed) from “fits neither” (framework defect)
🟢 Outline spruing, burnout, and casting metallurgy
🟢 Describe master-model duplication geometry (one for blockout/casting, one for processing)
🟢 Describe alternative bite-registration materials (silicone, wax, PVS putty)

L10 RPDs Summary

🔴 Self-assess Kennedy + Applegate fluency on at least 5 example cases (mixed classes and modifications)
🔴 Recite the six retentive-unit requirements without prompts (Support, Stabilization, Retention, Reciprocity, Engagement, Passivity)
🔴 Recite the three hazards of poor RPD design (decay, pathologic tissue change including bone resorption, TMJ dysfunction)
🔴 Apply Class-specific design rules: Class I/II — rotation control + cross-arch rigidity + indirect retention essential; Class III — tooth-supported, indirect retainers may be optional, focus on hygiene + aesthetics; Class IV — aesthetics + lip support + canine guidance dominant
🔴 Recite the five core design principles (maximize support, rigidity, bracing, stability, stress distribution)
🟡 Recite the suprabulge vs infrabulge mechanical distinction (occlusal vs apical approach; continuous vs short crown contact)
🟡 Walk through the design workflow (diagnose → classify → survey → mouth prep → component selection → impression / base extension)
🟡 List the five guiding-plane benefits (stability, reduced food trapping, controlled movement, proximal-plate effectiveness, indirect-retainer effectiveness)
🟢 Recite verbatim the textbook definitions of support, retention, indirect retention, bracing, reciprocation, and stability
🟢 Compare intracoronal precision attachments vs extracoronal clasps (cost, aesthetics, lab complexity)
🟢 Recite the design-error catalogue (planes too short, divergent surfaces, accidental new undercuts)

Quartz 4

Explorer

LOs

RPD Learning Objectives

Master High-Yield Checklist

L1 Introduction to RPD

L2 Components and Classifications

L3 Rests and Rest Seats

L4 Clasp Assembly

L5 Major and Minor Connectors

L6 Dental Surveyor

L7 Survey and Design

L8 Mouth preparation for RPD

L9 Clinical Sequence

L10 RPDs Summary

Graph View

Table of Contents