Dental Occlusion Concepts Quiz

Questions and Answers

What is the vertical dimension at occlusion (VDO)?

The vertical dimension at occlusion (VDO) is the vertical dimension where the teeth, or occlusal rims, are in contact.

How can the vertical dimension of rest (VDR) be measured?

To measure VDR, place a dot on the tip of the nose and chin, then have the patient lick their lips and close slowly until their lips barely touch.

What is a facebow transfer and why is it important?

A facebow transfer is used to relate the maxillary arch to the skull via a third reference point, ensuring accurate orientation of the maxillary cast on the articulator.

Describe the process to record centric relation.

Centric relation is recorded by using wax occlusion rims at the vertical dimension of occlusion, creating a space for registration materials in the mandibular record block. Signup and view all the answers

How can one evaluate the vertical dimension during denture fitting?

To evaluate the vertical dimension, record a new VDR, and observe the patient's ability to produce sibilant sounds while ensuring the maxillary and mandibular anterior teeth have a slight space. Signup and view all the answers

What is the objective of the occlusal plane?

To determine the horizontal and vertical level of the teeth. Signup and view all the answers

What does the vertical dimension at rest measure?

It measures the amount of space between the rims with the jaws at rest. Signup and view all the answers

What is the purpose of a face-bow transfer?

To record the position of the jaws in relation to the opening axis of the mandible. Signup and view all the answers

How is the occlusal plane established in relation to anatomical landmarks?

It is established by being parallel to Camper's Line and the pupils of the eyes. Signup and view all the answers

What are the key steps in marking the maxillary rim for teeth selection?

Mark the midline, the corner of the lips, and the high lip line during a broad smile. Signup and view all the answers

Study Notes

Occlusal Plane and Vertical Dimension

The occlusal plane determines the horizontal and vertical levels of teeth.
Vertical dimension measures space between rims at rest and in occlusion.
Centric relation records the most posterior position of the mandible to the maxilla.
Freeway space is the interocclusal space, typically 2-4 mm (difference between VDR and VDO).
Vertical dimension at rest (VDR) involves no teeth contact and relaxed muscles.
Vertical dimension at occlusion (VDO) occurs when teeth occlude.

Face-Bow Transfer and Centric Relation

Face-bow transfer records jaw position related to the mandible's opening axis.
Centric relation is retrievable and essential for edentulous patients.
Centric relation is recorded using wax rims at the vertical dimension of occlusion.

Marking Occlusion Rims and Establishing Occlusal Plane

Maxillary rims should have approximate lengths: 22 mm anterior, 20 mm posterior, and width of 3-5 mm anteriorly and 6-10 mm posteriorly.
Occlusal plane is an imaginary surface touching the incisal edges of anterior teeth and cusps of posterior teeth.
Rims should align parallel to Camper's Line and the pupils of the eyes.
Correct length of maxillary rim is dictated by the relaxed upper lip position.

Denture Creation Steps

To evaluate vertical dimension, record VDR, observe patient at speech, and ensure comfortable closure.
Beading the maxillary cast aids in transferring major connector designs and tissue contact.
The swing-lock consists of a labial bar hinge-latched to the major connector for missing abutments.

Major Connectors and Their Applications

Mandibular major connectors include lingual bar, lingual plate, sublingual bar, and labial bar.
Indications for a lingual bar include adequate space and no inoperable tori or frena.
Indications for a linguo-plate include close proximity of alveolar sulcus and future tooth replacements.
Complete palatal plates are suited for situations with extensive missing anterior teeth or poor abutment support.

Blockout Techniques

Blockout eliminates undesirable undercuts to aid in framework design.
Shaped blockout is used to locate clasp arms; parallel blockout is for guiding planes.
Relief is provided in areas where connectors contact thin tissues.

Use of Diagnostic Casts and Treatment Options

Diagnostic casts supplement exams, provide surveys of dental arches, and offer references during treatment.
Treatment options for short modification spaces (≤3 missing teeth) include natural tooth-supported fixed prostheses or removable partial dentures.