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Major CONNECTORS (Mandibular)+Minor Dr Shaima’a Ahmed Radwan

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Major CONNECTORS (Mandibular)+Minor

Dr Shaima’a Ahmed Radwan

Join the component parts of RPD together.

Functions of mandibular connectors

Structural Requirements for Mandibular Major Connectors

1- Rigid and should provide cross arch stabilization and broad load distribution.

2- Relieved to avoid settling into the mucosa

The superior border should be placed away by 3-5 mm

the gingival margin should be relieved.

The borders should run parallel to the gingival margin

The inferior border should be gently rounded above the moving tissues of the floor of the mouth.Impingement of gingival tissues should be avoided.

TYPES OF MANDIBULAR MAJOR CONNECTORS

LINGUAL BAR. SUBLINGUAL BAR. DOUBLE LINGUAL BAR. (KENNEDY BAR) CINGULUM BAR. LABIAL BAR.

PLATE BARS LINGUAL PLATE

3-5mm

3-4 mm

3-5mm

Location and Form

LINGUAL BAR

MEASUREMENT OF LINGUAL SULCUS (8mm).

Half-pear shape in cross section, tapered superiorly with the broader and thicker portion at the inferior border.

LINGUAL BAR

LINGUAL BAR

The inferior border should be gently rounded above the moving tissues of the floor of the mouth; to avoid irritation or injuring the subadjacent tissues when the

restoration moves

LINGUAL BAR

The bar should be relieved sufficiently but not excessively over the underlying tissues.

Function: The lingual bar functions only as a major connector. It does not provide neither support nor indirect retention.

Contraindications:-Bilateral torus mandibularis

- Contraindications: High lingual frenular attachment

- Contraindications: Undercut on the lingual side of the ridge

Contraindications: - Inadequate space

- Extreme lingual inclination of lower anterior teeth.

• Location and form: • Extending over and parallel to the anterior floor of the mouth.

SUBLINGUAL BAR

• It has a tear drop configuration whose base is towards the base of the tongue.

• Indications : Insufficient depth of alveololingual sulcus.

• Contraindication: Highly attached lingual frenum. torus madibularis ,lingual inclined anterior teeth

THE DOUBLE LINGUAL BAR KENNEDY BAR A Secondary lingual bar

Cingulum bar (Kennedy bar).

lingual bar

Two supporting rests must be placed one on each end of the Kennedy bar. These rests prevent settling of the bar during function, thus preventing laceration of the gingiva and act as indirect

Retainers

Kennedy bar is neither a major connector nor indirect retainer by itself

•Allows natural stimulation •stabilization •Rigidity •Proper distribution of the stresses •Splinting •No gingival coverage.. •I.R. through its terminal rests

•Objectionable to the tongue •Collect food •Phonetic problems.

LINGUAL PLATE

Cross-arch stabilization ,Splinting for weak teeth

LINGUAL PLATE Indications: 1- High floor of the mouth and high frenal attachment. 2- When future teeth replacement is anticipated. 3- Splinting of periodontally affected tee AdvantAGES 1- The most rigid connector. 2- Can act as indirect retainer. 3- Provides splinting if used in conjuncton with labial Disadvantage 1- Covers gingiva and teeth; so no gingival stimulation. Patient is instructed to massage the gingiva. 2- May contribute to caries and periodontal disease.

LINGUAL PLATE

Interrupted lingual plate

1- The superior border should be

Scalloped and projected to the contact points between the projections the border should not exceed the middle third of the teeth.

b- Positively contacting the teeth.

c- As thin as possible.

2- It is relieved at the gingival

margin.

3- It is provided with slots in case

of diastema.

4- Lingual area should be surveyed

to block out undercuts.

LABIAL BAR Form and Location:

• Thick and bulk than a lingual bar to

counteract the increased flexibility due to increased length.

• Half-pear shaped with bulkiest

potion located inferiorly,

• Runs across the labial and buccal mucosa.

• Superior border tapered to soft tissue

located at least 4 mm below the

gingival margin.

• Must be relieved over the canine

eminence

lacks sufficient rigidity So made thick.

Labial vestibular depth must be adequate especially in the presence of

gingival recession

Disadvantages:

Swing lock

Connected to a lingual plate m. c. by a hinge device at one end and a locking device at the other end. Vertical minor connectors arise from the labial bar touch the anterior teeth below the survey line

Mandibular major connectors

Lingual Plate

Lingual bar

Sublingual Bar

double lingual bar

Labial bar

DOUBLE LINGUAL BAR Sublingual bar

Linguoplate Swing lock

It is the part of the partial denture, that connects units of the prosthesis with either the major connector or the denture base.

Form and location

The minor connector should located on axial surface

They should join the major connector at right angle to cover as little as possible of the gingiva.

The minimum space between two minor connector 5mm

Functions and form:

Connect different units with saddle or major connector.

– should be tolerable to the tongue.

Between two adjacent teeth

Embrasure Minor Connectors

Grid work Minor Connectors

Open lattice work or mesh types