Types of Maxillary Major Connector

Type Requirements Advantages Disadvantages Indications Contraindications1- Palatal bar - Narrow half oval with it's

thickest point at the center.- Gently curved and shouldn't produce sharp angle at junction with the denture base.

1- common used for many years.2- now, used as interim application.

1- To provide rigidity it must be bulky.2- Patient discomfort3- Narrow antero-posteriorly (↓ vertical support from the bony plate).

- Only in short span Kennedy class III application.

- Shouldn't be placed anterior to 2nd premolar

↓(It's bulk may produce noticeable discomfort& speech alteration).

2- Palatal strap

- Wide band of metal with a thin cross sectional dimension.- The most versatile and unobtrusive major connector.- Shouldn't ↓ than 8mm in width to avoid compromising rigidity.- ↑ the edentulous span length → ↑ Strap width:a) Ensure rigidity.b) Greater support from hard palate.

1- located in two or more planes.

↓(offers ↑ resistance to bending and twisting forces).

↓[L-Beam principle]

2- Strong so, can be kept relatively thin.3- ↓ interference with normal tongue action.4- Pt. acceptance.5- Distribute the applied stresses over a large area.

1- Pt. complaint from excessive palatal coverage:a) Anterior border:Posterior to palatal ruga or at the posterior slope of prominent ruga.b) Posterior border:.Anterior to junction of The Hard & The Soft palate. 2- ↑ Soft tissue coverage

↓(Papillary hyperplasia) Due ↓ toa) Denture wearing 24 hour daily.b) Poor oral hygiene.c) Inadequate Pt. instructions.

- Unilateral distal extension R.P.D. (Class II Kennedy Classification ).

- Bilateral distal extension R.P.D.(Class I Kennedy Classification).

Type Requirements Advantages Disadvantages Indications Contraindications

3- Antero-posterior

palatal bar

- Both characteristics of palatal bar and palatal strap major connectors:a) Anterior bar (flat) as palatal strap.b) Posterior bar (half oval) as palatal bar.- [Circle effect] : Gives rigidity.- [L-Beam effect] : lying in different planes.

1- Rigidity is the main advantages.2- Minimize soft tissue coverage.3- Exceptional resistance to deformation.

1- Frequently uncomfortable.2- May annoy the tongue.3- May interfere with phonetics.4- ↓ support from the bony plate.

- When support isn't a major consideration.- When anterior and posterior abutments are widely separated.- Pt. with large palatal tori that can't be removed.

- Pt.'s with reduced Periodontal support.- Selected only if other choices have been considered& eliminated

4- Horseshoe connector

- Thin band of metal running along the lingual surfaces of the remaining teeth& extended onto the palatal tissues for 6-8 mm.- Rigidity can increased by extending the borders slightly onto the horizontal surfaces of the hard palate.- Should display symmetry- Should extend to the same height on both sides.- All borders should be gently curved& smooth.

1- Reasonably strong.2- Some vertical support from hard palate.3- Avoid bony prominence without affecting the vertical support.

1- Tendency for the connector to flex or deform. ↓(Stress concentration)

↓(Abutment damage)

2- To avoid flexing, It should be thicker than other major connectors.

(↑ bulk) ↓

(Pt. discomfort& affecting Phonetics)

- When several anterior teeth are being replaced.- Presence of a prominent Median suture line or torus.- Considered only if more rigid connectors can't be used.

- Poor indication for distal extension R.P.D.- When cross arch stabilization is required.

Type Requirements Advantages Disadvantages Indications Contraindications

5- Antero posterior

palatal strap

- Each strap 8mm in width at least and relatively thin in cross section.- Borders 6mm away from the gingival margin or extended to the palatal surface of remaining teeth.- Palatal borders should be smooth& curved.- When ant. teeth replaced:a) Anterior strap:Most posterior position.b) Posterior strap:Posterior position without contact the soft palate.- Open area: 20×15 at least

1- Rigid.2- Good support from hard palate.3- Metal over ruga is corrugated → ↑strength &↓ thickness ( < 1mm).4- [Circle effect].5- [L-Beam effect].

1- Metal over ruga area may be thinner than other connectors.2- Phonetics may be encountered.3- Extensive length of the borders may cause irritation to the tongue.

- Numerous teeth are to be replaced.- Presence of tori.- When cross arch stabilization is required.

- If the open area ↓ than 15×20 mm other major connectors are preferred as:a) Wide palatal strap.b) Complete palate.c) Modified complete palate.

6- Complete palate

- ↑↑↑ rigidity& support.- ↑↑↑ Tissue coverage.- Anterior border 6mm away from the gingival margin or must cover the cingula of anterior teeth.- Slight mechanical seal by beading the post. border.- Post. Palatal seal should not be used in R.P.D. :a) Tissue rebounding will cause additional stresses.b) border molding can't be obtained.

1- Proper distribution of the applied stresses.2- Provide additional stabilization for the prosthesis.3-Intimate contact between connector& the hard palate:a) Dissipate the lateral& horizontal forces.b) ↑ the retention.4- Pt. comfortable.5- Little or no effect on phonetics.6- [L-Beam effect].7- Thermal conductivity8- Not porous.

1- Extensive tissue coverage may cause (Soft tissue hyperplasia) Due↓ toa) Poor oral hygiene.b) Prolonged denture wear.2- Phonetics may be encountered.

- When all posterior teeth are to be replaced.- Remaining teeth are periodontally compromised.