Introduction of fixed prosthodontic. Prosthesis: an artificial appliance which replace of missing or...

Introduction of fixed

prosthodontic

Prosthesis: an artificial appliance which replace of missing or absent part of the human bodyProsthodontics:

it is that branch of dentistry concerned with restoration and maintenance of oral function, comfort, appearance, and health of the patient by the restoration of the natural teeth or the replacement of the missing teeth with

artificial substitutes .

Removable prosthodontics:

Its that branch of prosthodontics concerned with replacement of the missing teeth by removable artificial substitutes.

Fixed prosthodontics:

it is that branch of prosthodontics concerned with the replacement of missing teeth by artificial substitutes that are not removable from the mouth.

Restoration A broad term applied to

any material or prosthesis that restore or replace lost tooth structure

CrownIt is the artificial restoration

of the coronal portion of the natural tooth.

Bridge It is a non removable prosthesis of a metallic or non metallic nature, spanning a space in the dental arch and firmly anchored at one or both ends to the adjacent teeth.

Jacket crown

it is a crown that cover and restore the whole coronal portion of the tooth

Post crown

It is an artificial restoration of the entire coronal potion of the tooth and is retained in position mainly by a post inserted in to a prepared root canal.

Full veneer metal crown

It is an artificial metallic crown constructed to fit over the whole coronal portion of the tooth

Full veneered metal crown

It is a full metallic crown with all surfaces covered with porcelain.

Veneered metal crown it is a full metallic crown with only one or two surfaces

covered with porcelain.

Three quarter crown it is a partial coverage crown covering all surfaces of

the tooth leaving the labial or the buccal surfaces, un prepared for conservative and esthetic reasons.

Reversed three quarter crownit is a modified form of the three quarter crown in which

the lingual surface( instead of labial or buccal is un prepared).

one half crown

it is a modified form of the “three quarter crown” in which one proximal surface, the adjacent halves of the buccal and lingual surfaces and most of the occlusal surface are covered, while the other half is left uncovered.

Seven eighth crown

It is a partial coverage crown with all surfaces prepared except the mesiobuccal cusp of the upper molar.

Pontic

it is that part of the bridge which replace the missing tooth and restore both function and appearance.

Abutment

it is the natural tooth, which supports and retains the bridge at one or both ends.

Retainer

It is the part of the bridge which retains the bridge to the abutments.

Connector

It is the part of the bridge which join the pontic to the retainer.

Simple bridge

it is one single bridge , which may be ‘fixed fixed’ or ‘ fixed supported’ .

Compound bridge

it is a combination type bridge composed of two or more of simple bridge i.e fixed fixed free or fixed fixed supported.

Complex bridge

It is a bridge, which extend from the anterior segment of the dental arch to the posterior one passing by the canine area.

Anterior bridge

it is a bridge, which extends from one canine on one passing by the canine area.

Posterior bridge

It is the bridge which begins after the canine area.

Unilateral bridge

it is the two or three units bridge, which dose not cross the midline of the arch it is either right or left bridge.

Bilateral bridgeit is the bridge, which crosses the midline of the arch.Fixed fixed bridgeit is the bridge in which the pontic is joined at one end to the

abutments by rigid connector while the other end is supported on the abutment by a rest non rigid connector to allow some movement between them.

Fixed free bridge [cantilever]

it is the bridge in which the pontic is fixed and takes its support from one or double retainers at one end only while the other end is unsupported or free.

Occlusion

May be defined as the contact of the opposing surfaces of the teeth of the two jaws.

Tempromandibular joint (TMJ)

Both anatomy of the cranio_mandibular articulation and capabilities of movement and limitation of the TMJ are very important are very important to dental profession , especially in the field of prosthodontics, this is due to a relationship between the motion of condyle and the positioning of artificial teeth

Centric relation

is a bone-to-bone relation, it is a relation between the maxilla and mandible when the condyle are in the most posterior retruded position in the glenoid fossa.

Centric occlusion

It is relation between upper and lower teeth tooth-to-tooth relation which provide maximum planned contact.

It is defined as being the occlusion of teeth as the mandible close in centric relation

Maximum intercuspationIt is the most closed complete interdigitation of mandibular and maxillary teeth irrespective of condylar centricity.

Maximum intercuspation may or may not coincide with centric occlusion depending in the position of the condyle.

Centric occluding relation:

It is a term some times used to describe the condition in which the jaws are in centric relation and the teeth or occlusal surfaces in centric occlusion.

Condylar movement

1. Rotation

It is the motion of the body around its axis,

Mandibulare rotation occurs in the lower compartment of the TMJ, between mandibular condylar and articular disc. Mandibular rotation occur around the rotational centers of the condyle

Hinge axis

Is the imaginary line connecting the rotational centers of one condyle with that opposite .and around which the mandible make opening and closing rotational movements.

2. Translation

Is the movements of a body when all its part move at the same time mandibular translation occur in the upper compartment of the TMJ between the disc and the glenoid fossa

The working side:

It is the side on which the chewing is being done at the movement; it is the side to which the mandible has moved.

The balancing side:

It is the side opposite to the working side. It is the side on which, although there is greater separation of the teeth, there is at least one point of contact between the upper and lower teeth. It is also the side on which the grater condylar movement has occurred

Curve of Spee (anteroposterior curve):

It is the anatomic curve established by the occlusal alignment of the teeth, beginning with the cusp tip of the mandibular canine and following the buccal cusp tips of premolar and molar teeth, continuing through the anterior border of the mandibular ramus, ending with the anterior most portion of the mandibular condyle.

Curve of Wilson (mediolateral curve):

It means in mandibular arch, that curve, as viewed in frontal plane, which is concave inferiorly and contacts the buccal and lingual cusps of the mandibular molars. In the maxillary arch, that curve, as viewed in frontal plane, which is convex superiorly and contacts the lingual and buccal cusps of the maxillary molars. The curved is formed by the facial and lingual cusp tips on both sides of dental arch.

Compensating curve:

It is anteroposterior curvature (in the median plane) and the mediolateral curvature (in the frontal plane) in the alignment of occluding surfaces and incisal edges of artificial teeth that are

used to develop balance articulation .

These curves introduced in the construction of complete dentures to compensate for the opening influences produced by the condylar and incisal guidance during lateral and protrusive mandibular excursive movements, these curves are artificial counterparts of the curve of Spee and monsoon, which are found in the natural dentition.

Curve of Menson:

It is the curve of occlusion in which each cusp and incisal edge touches or conforms to a segment of the surface of a sphere 8 inches in diameter with its center in the region of the glabella.