Components of Removable Partial Denture PDF

Components of Removable Partial Denture Introduction to Major Connectors McCracken’s Removable Partial Prosthodontics 12th Edition Ch 5 Pages 29 – 39, 39 - 45 Components of Removable Partial Denture A removable prosthesis must extend to both sides of the arch Optimum stability owing to equal dist...

Components of Removable Partial Denture Introduction to Major Connectors McCracken’s Removable Partial Prosthodontics 12th Edition Ch 5 Pages 29 – 39, 39 - 45 Components of Removable Partial Denture A removable prosthesis must extend to both sides of the arch Optimum stability owing to equal distribution of functional loads to all supporting teeth and tissues Optimum resistance owing to the cross-arch tooth contact 2 Components of Removable Partial Denture MAJOR CONNECTORS REPLACEMENT TEETH MINOR CONNECTORS REMOVABLE PARTIAL DENTURE DENTURE BASE DIRECT RETAINERS INDIRECT RETAINERS 3 MAJOR CONNECTORS DEFINITION A major connector is the component of the partial denture that connects the parts of the prosthesis located on one side of the arch with those on the opposite side. It is that unit of the partial denture to which all other parts are directly or indirectly attached. 4 MAJOR CONNECTORS FUNCTIONS 1. Unification of major parts of the prosthesis 2. Distribution of applied forces throughout the arch to selected teeth and tissues 3. Minimization of torque to the teeth 5 MAJOR CONNECTORS REQUIREMENTS 1. Rigid 2. Provide cross-arch stability 3. Free of movable tissues 4. Avoid impinging gingival tissues when seated 5. Avoid bony and soft tissue prominences during placement and removal 6 MANDIBULAR MAJOR CONNECTORS 7 MANDIBULAR MAJOR CONNECTORS ADDITIONAL FEATURES 1. Should not have intimate contact with underlying soft tissues of the floor of the mouth as they are movable tissues 2. Is usually half pear-shaped or half round in cross section 3. Type of major connector used depends on functional depth of the lingual vestibule 8 MANDIBULAR MAJOR CONNECTORS 1. LINGUAL BAR - Borders of the connectors should be at least 4 mm away from the gingival margins and run parallel to it - Functional depth of the lingual vestibule should not be less than 8 mm 9 MANDIBULAR MAJOR CONNECTORS 2. LINGUOPLATE - Functional depth of the lingual vestibule is less than 8 mm - Apron of metal extending onto the supracingular surface of the anterior teeth - Relief is provided for soft tissue and at any location where the framework crosses the marginal gingiva - Interrupted linguoplate in the presence of interproximal spaces. 10 MANDIBULAR MAJOR CONNECTORS 3. SUBLINGUAL BAR - Indications - Functional depth of the lingual vestibule is less than 8 mm - Presence of anterior lingual undercut - Contraindications - Lingual Tori - High attachment of Lingual frenum - Interference with elevation of floor of mouth 11 MANDIBULAR MAJOR CONNECTORS 4. CINGULUM BAR (CONTINUOUS BAR) - Upper portion of this major connector is located on the cingula of anterior teeth - Positive support by rests is a must - Indication: the axial alignment of the anterior teeth is such that excessive blockout of interproximal undercuts must be made - Limitation: Lack of rigidity 12 MANDIBULAR MAJOR CONNECTORS 5. LINGUAL BAR WITH CINGULUM BAR - Upper portion of this major connector is located on the cingula of anterior teeth - Positive support by rests is a must - Indication: As an alternative to Linguoplate - Limitation: food entrapment 13 MANDIBULAR MAJOR CONNECTORS 6. LABIAL BAR Very rarely used Indications - Extreme lingual inclination of incisors and premolars - Inoperable Mandibular Tori Most often recontouring of the remaining teeth with restorations or the surgical removal of tori is advocated over the use of this. 14 MAXILLARY MAJOR CONNECTORS 15 MAXILLARY MAJOR CONNECTORS ADDITIONAL FEATURES 1. Should cross the midline at a right angle rather than on a diagonal 2. Should have intimate contact with underlying tissues of palate 3. Borders of the connectors should be at least 6 mm away from the gingival margins and run parallel to it 4. Anterior borders of extensive MCs should follow the contours between the crests of the rugae (in the valleys) 5. Posterior border should be just anterior to the Anterior Vibrating Line 16 MAXILLARY MAJOR CONNECTORS 1. SINGLE PALATAL STRAP - Bilateral tooth-supported prostheses - Distributed in three planes - Thickness = 0.8 mm - Minimum Anterio-posterior width = 8 mm - Indicated for posterior bounded saddles 17 MAXILLARY MAJOR CONNECTORS 2. COMBINATION ANTERIOR AND POSTERIOR PALATAL STRAP - Extremely rigid and flexure is non-existent - Thickness = 0.8 mm - Minimum Anterio-posterior width = 8 mm - Very versatile and can be used for any Kennedy Class - Contraindication – extensive inoperable tori 18 MAXILLARY MAJOR CONNECTORS 3. PALATAL PLATE - Thin, broad, contoured palatal coverage used as a maxillary major connector and covering one half or more of the hard palate - Indicated for extensive Class I cases where the distal abutment is either the canine or first premolar. 19 MAXILLARY MAJOR CONNECTORS 4. U-SHAPED PALATAL CONNECTOR (HORSE SHOE SHAPED) - Least desirable of Maxillary Major Connectors - Mechanically weaker - Indications - When a large inoperable palatal torus exists - Occasionally when several anterior teeth are to be replaced (Class IV) 20 MAXILLARY MAJOR CONNECTORS 5. SINGLE PALATAL BAR - Most objectionable Connector Maxillary Major - Bulky to obtain rigidity, interferes with tongue function - Rarely indicated 21 MAXILLARY MAJOR CONNECTORS 6. ANTERIOR-POSTERIOR PALATAL BAR - Structurally same disadvantage as Single Palatal Bar - Bulky to obtain rigidity, interferes with tongue function - Rarely indicated 22 Next Lecture Minor Connectors and their specifications McCracken’s Removable Partial Prosthodontics 12th Edition Ch 5 Pages 46 – 49 23