major connectors (mandibular)+minor major connectors (mandibular)+minor dr shaimaâ€™a ahmed...
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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
Location and Form
MEASUREMENT OF LINGUAL SULCUS (8mm).
Half-pear shape in cross section, tapered superiorly with the broader and thicker portion at the inferior border.
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
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.
• 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).
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
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.
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.
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
3- It is provided with slots in case
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
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
double lingual 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