1. Definition
    1. It is the unit of partial denture that connects parts of prosthesis on one side of the arch with those on the opposite side
  2. Functions
    1. Unification of major parts of prosthesis
    2. Force/stress distribution throughout the arch
    3. Cross arch stability
    4. Resists flexing & torque
  3. Ideal requirements
    1. It should be rigid
    2. Shouldn't impinge on free gingival margin & other soft tissues
    3. Shouldn't allow food lodgement
    4. Should provide vertical support for RPD
    5. Should provide indirect retention when needed
    6. Should be comfortable to the patient
  4. Maxillary Major connectors
    1. 6 types
      1. Single palatal strap
        1. Wide, thin band of metal that runs across the palate unobtrusively
        2. Indications :- ▪︎Unilateral distal extention (Class II) ▪︎Tooth supported short span bilateral edentulous areas (Class III)
      2. Combination anterior & posterior palatal strap
        1. Indications :- ▪︎Numerous teeth are to be replaced & torus is present ▪︎Kennedy's Class I & II ▪︎Long edentulous spans in Class II Mod I arches ▪︎Class IV arches in which anterior teeth must be replaced with RPD
      3. Palatal plate
      4. U-shaped palatal strap/Horseshoe shaped
        1. Least rigid palatal major connector
        2. ▪︎It's not considered rigid enough & doesn't allow distribution of forces from one side of arch to the other. Hence it's not indicated in any case
        3. Indications :- ▪︎Class IV anterior teeth replacement ▪︎Patients with Tori & prominent mid palatine suture ▪︎Excessive vertical overlap of anterior teeth ▪︎Need to stabilize anterior teeth
      5. Single palatal bar
        1. It's a bar running across the palate which is narrow half oval in cross-section with thickest point in the centre
        2. Advantages:- Greater rigidity & less bulky
        3. Disadvantages - problems with thick palatal bar are :- ▪︎Obstruction to tongue ▪︎Difficulty in swallowing
        4. Indications :- ▪︎Interim partial dentures ▪︎Kennedy's class III limited to replacing one or two teeth on each side of arch
      6. Anterior-posterior palatal bars
        1. Most rigid palatal major connector
        2. ▪︎Has 2 bars : one anteriorly & other posteriorly, connected by a flat longitudinal elements on each side of lateral slope of palate ▪︎Anterior bar is strap like while posterior bar is half oval in shape ▪︎Anterior bar is placed in btw rugae valleys ▪︎Posterior bar is placed at the junction of hard & soft palate
        3. Indications :- ▪︎Patients with large inoperable tori ▪︎ Anterior & posterior abutments are widely separated ▪︎ Patients who want less palatal coverage ▪︎Single palatal bar connector would flex
    2. Summary of Indications
      1. Class I
        1. Closed Horseshoe, complete palate
      2. Class II
        1. Palatal strap, Closed Horseshoe
      3. Class III
        1. Palatal strap, palatal bar
      4. Class IV
        1. Horseshoe, closed horseshoe, complete palate
  5. Mandibular Major connectors
    1. Lingual bar
      1. Most commonly used
      2. 6 gauge Half pear shaped with superior border located 4mm below the gingival margin
      3. Requires atleast 8mm of vertical space btw floor of mouth(FOM)& gingival margins of teeth
      4. Indications:- ▪︎Lingual sulcus is deep ▪︎Kennedy's class 3 & it's modifications
    2. Linguoplate
      1. Pear shaped Lingual bar with superior border extending onto Lingual surfaces of teeth as thin solid plate of metal
      2. Support is provided by Rests
      3. Indications:- ▪︎Shallow lingual sulcus with inadequate space for lingual bar ▪︎Class I distal extention with excessive bone resorption ▪︎Long span edentulous ridges, class I or II RPD ▪︎When remaining teeth have limited PDL support ▪︎When future replacement of 1 or more teeth is deemed required
    3. Sublingual bar
      1. Modification of lingual bar
      2. Indications
        1. Used when height of FOM in relation to free gingival margin is less than 6mm
    4. Double lingual bar/ continuous bar (cingulum bar)/ Kennedy's Bar
    5. Labial bar