COMPLETE DENTURE

 WHAT IS COMPLETE DENTURE PROSTHODONTICS

 

Complete denture prosthodontics or Full denture prosthetics is defined as “The replacement of the natural teeth in the arch and their associated parts by artificial substitutes”- GPT.

 It can also be defined as “The art and science of the restoration of an edentulous mouth” - GPT.

Complete denture is defined as “ A dental prosthesis which replaces the entire dentition and associated structures of the maxilla and mandible” - GPT. It can be classified as,

• Removable complete dentures

• Fixed complete dentures

Generally complete dentures are fabricated for geriatric patients. Some young patients who are born with congenitally malformed teeth or edentulous arches require complete dentures. It is essential for the dentist to evaluate the patient before treatment.

Functions of a Complete Denture

A complete denture functions to restore

aesthetics,

mastication

and speech.

Parts of a Complete Denture

 The various parts of a complete denture are:

 Denture base.

Denture flange.

 Denture border.

Denture teeth.

Denture Base

 It is defined as, “That part of a denture which rests on the oral mucosa and to which teeth are attached” – GPT. It is usually made in acrylic resin. In some cases metal denture bases are prepared. The denture base forms the foundation of the denture. It helps to distribute and transmit all the forces acting on the denture teeth to the basal tissues. It has the maximum influence on the health of the oral tissues. It is the part of the denture, which is responsible for retention and support.

Acrylic Resin Denture Bases

 It is the most commonly used denture base material

It is easy to fabricate and economical.

 It is supplied as a powder (polymer) and a liquid (monomer).

Advantages of Acrylic Denture Base

• Acrylic has a translucent pink colour, which closely resembles the gingiva, providing good aesthetics.

 • These dentures can be easily rebased/relined as required in future.

• It is also available in various pigmented colours which can be used for characterization.

• The material is quite strong and can withstand normal occlusal forces.

Disadvantages of Acrylic Denture Base

• It cannot be used in thin sections like a metal denture base.

 Hence, it affects the speech of the patient.

• It does not transmit any heat. So the patient’s perception of the temperature of the food is decreased.

 • Difficult to maintain.

 Metal Denture Bases

Metal denture bases can be fabricated using Gold, Gold alloys, Chromium-Cobalt or Nicke Chromium alloys

 Advantages of Metal Denture Bases

 • Mandibular dentures are heavier. So the retention and stability are improved.

• Improved thermal conductivity gives good sensory interpretation.

 • They are strong even in thin sections. Thin sections are very comfortable for the patient.

• Easier to maintain.

Disadvantages of Metal Denture Bases

• More expensive.

 • Require more time for fabrication.

• Require refractory cast material.

• Difficult to fabricate.

• Cannot be rebased.

Flange of a Denture

 It is defined as, “The essentially vertical extension from the body of the denture into one of the vestibules of the oral cavity. Also, on the mandibular denture, the essentially vertical extension along the lingual side of the alveololingual sulcus”- GPT. It has two surfaces, namely, the internal basal seat surface and the external labial or lingual surface.

The functions of the flange include,

providing peripheral seal

and horizontal stability to the denture.

The flanges are named based on the vestibule they extend into.

Labial Flange It is defined as,

“The portion of the flange of the denture which occupies the labial vestibule of the mouth”- GPT. Thickness of this flange provides aesthetic lip support. It has a “V” shaped notch to accommodate the labial frenum

 Buccal Flange It is defined as,

“The portion of a flange of a denture which occupies the buccal vestibule of the mouth”— GPT. It provides the required cheek fullness in aged edentulous patients. In the mandibular denture it also transmits the occlusal forces to the buccal shelf area. The buccal frenum is attached to active muscle fibres, hence, additional relief should be provided in the buccal flange.

Lingual Flange It is defined as,

 “The portion of the flange of a mandibular denture which occupies the space adjacent to the tongue”-GPT. It should be in contact with the floor of the mouth to provide peripheral seal. However, overextended lingual flanges can lead to loss of retention due to displacement during the activation of the muscles of the floor of the mouth.

Denture Border It is defined as,

 “The margin of the denture base at the junction of the polished surface and the impression surface”- GPT It is responsible for peripheral seal. The denture border should be devoid of sharp edges and nodules to avoid soft tissue injury. Over[1]extended denture borders can cause hyperplastic tissue changes like epulis fissuratum. On the other hand the border should not be under-extended as peripheral seal may be lost.

Denture Teeth

It is the most important part of the complete denture from the patient’s point of view. The functions of the denture teeth are aesthetics, mastication and speech. They are usually made of acrylic resin or porcelain. There are different types of denture teeth which are classified as follows: Based on the material:

 • Acrylic teeth.

• Porcelain teeth.

 • Inter-penetrating polymer network resin teeth (IPN resin).

 • Gold occlusals.

 • Acrylic resin with amalgam stops.

Based on the morphology of the teeth:

• Anatomic teeth.

• Semi-anatomic teeth.

A complete denture has the following surfaces 

 Impression surface (Intaglio surface):

 It is defined as, “That portion of the denture surface which has its contour determined by the impression”- GPT. This surface refers to the surface of the denture that will be in contact with the tissues (basal seat area and limiting structures) when the denture is seated in the mouth. This surface is a negative replica of the tissue surface of the patient. It should be free of voids and nodules to avoid injury to the tissues.

 Polished surface (Cameo surface) 

It is defined as, “That portion of a surface of a denture which extends in an occlusal direction from the border of the denture and includes the palatal surfaces. It is the part of the denture base which is usually polished, and it includes the buccal and lingual surfaces of the teeth” – GPT. This surface refers to the external surfaces of the lingual, buccal, labial flanges and the external palatal surface of the denture. This surface should be well polished and smooth to avoid collection of food debris.

 Occlusal surface

 It is defined as, “That portion of the surface of a denture or dentition which makes contact or near contact with the corresponding surface of the opposing denture or dentition”—GPT. This surface refers to the occlusal surface of the denture teeth. It resembles the natural teeth and usually contains cusps and sluice ways to aid in mastication.

STEPS OF COMPLETE DENTURE FABRICATION