Prothodontics

• A Complete denture is the replacement of the natural teeth in the arch and their associated parts by artificial substitutes.
• Another definition of complete denture is a dental prosthesis which replaces the entire dentition and associated structures of the maxilla and mandible.
• The advantages of acrylic based complete dentures include good aesthetics with transparent pink colour like the gingiva, can easily be rebased or relined, and are available in different pigmented colours.
• The disadvantages of acrylic based complete dentures include cannot be used in thin sections like the metal denture base, and affects speech of the patient.
• The advantages of metal based complete dentures include improved thermal conductivity gives good sensory interpretation, strong even in thin sections which is very comfortable for the patient, and are easier to maintain.
• The disadvantages of metal based complete dentures include are more expensive, require more time for fabrication, require refractory cast material, are difficult to fabricate, and cannot be rebased.
• The functions of replacing teeth with Complete Dentures include aesthetics to restore lost facial contours, vertical dimension and incorporation of stains on dentition to improve appearance, mastication to enhance the stability of the denture, and phonetics to restore speech in patient using complete denture.
• Causes of tooth loss include caries, periodontal disease, abscess, trauma, orthodontic reasons, and congenital/developmental systemic factors such as diabetes, bone disease, hormonal changes, smoking, stress, obesity, and age.
• The limitations of Complete Dentures include resorption and prosthetic replacement of alveolar bone, which depends on the inherent quality and size of the alveolar ridge, the technique used for tooth extraction, the healing capacity of the patient and the overall loads applied on the ridge.
• Another limitation of Complete Dentures is the restoration of appearance, as in the edentulous patient, premature ageing is seen as a result of loss of tonicity of facial muscles and inability to function effectively regardless of presence of complete dentures.
• Symptoms of lack of lingual overjet include tongue biting, which can be treated by removing lower lingual cusps or resetting teeth.
• Neuromuscular control can be affected by incorrect shape of denture, lingual position of molars, occlusal plane too high, and upper molars buccal to ridge.
• Treatment for vertical dimension of occlusion more than patient can tolerate includes grinding to provide functional width of sulcus if less than 1.5mm, or resetting dentures at new occlusal vertical dimension if greater than 1.5mm.
• Post insertion of Dentures can lead to faults, complications and solutions such as vertical dimension of occlusion more than patient can tolerate, cheek and lip biting, lack of lingual overjet, and xerostomia.
• Xerostomia reduces the ability to form a suitable seal, and can be caused by medication, irradiation of the head/neck, and salivary gland disease.
• For lips, grind lower incisors to provide a more appropriate incisal guidance angle.
• Treatment for complications related to polished surfaces includes using disclosing material to accurately define the area involved, relieving and repolishing.
• Other treatment options for edentulous patients include implant supported and implant retained prosthesis, overdentures, precision attachments, and bone graft for deficit or atrophied edentulous +/- implants or dentures.
• Lack of lingual overjet is often due to teeth generally placed lingual to lower ridge.
• Design dentures to maximise retention and minimise displacing forces, and prescribe artificial saliva.
• For cheek biting, restore functional width of sulcus and reset dentures.
• Post insertion of Dentures can lead to complications related to polished surfaces such as a flange on the buccal aspect of tuberosity being too thick and constraining the coronoid process, causing pain at the posterior aspect of the upper denture on opening.
• Symptoms of vertical dimension of occlusion more than patient can tolerate include pain around the periphery of dentures possibly accompanied by pain in the masseter and posterior temporalis.
• Correct design faults such as removal of lingual cusps of posterior teeth, flattening polished lingual surface, and adjusting the occlusal plane.
• Before inserting the denture, the clinician should examine the borders of the denture to check for any sharp projections or rough ends.
• The function of the Prosthesis is examined by evaluating the retention and stability of the denture, checking for any kind of displacement during the chewing cycle and speech, and checking the jaw relation.
• Speech is one of the most challenging functions which should be reproduced in a denture.
• Placing retentive grooves on the artificial teeth is a part of the Compression Moulding Technique.
• The fit of the Prosthesis is examined by examining the Dentures, the oral mucosa, the adaptation, border extension, frenal relief, and aesthetics.
• Denture processing involves two techniques: Compression moulding and Injection moulding.
• Checking for fit and function of a denture includes examining the Dentures, the tissue surface, the oral mucosa, the adaptation, border extension, frenal relief, and aesthetics.
• The success of a denture depends on the fit and function which includes proper adaptation, patient comfort, adequate extension, aesthetics, occlusal harmony, speech, accurate jaw relation, retention and stability during mastication.
• Types of Separating media used in Compression Moulding Technique include Tinfoil, Cellulose lacquers, Solution of alginated compounds sodium alginate(Cold mould seal), Calcium oleate, Soft soaps, Sodium silicate, Starches, Evaporated milk.
• Dewaxing is a part of the Compression Moulding Technique.
• The denture wearers have a shallow pronunciation because of the smooth palatal surface.
• Compression Moulding Technique involves preparation of the trial denture, disarticulation, flaskcard>
• The tissue surface of the denture is examined for the presence of voids or nodules.
• Application of separating medium, mixing of powder and liquid, packing, curing, cooling, deflasking are steps in the Compression Moulding Technique.
• The older edentulous patient faces changes in the body that affect the ability to cope with complete dentures, including progressive loss of sensory neurones and synapses in the cerebral cortex slowing down the response to sensory stimuli, impairment of motor functions such as contraction of the masseter muscles which become slow with natural teeth resulting to less chewing force, and with dentures become even slower, and others include osteoporosis and mucosal thinning of denture bearing tissues.
• Regular follow-up is important to achieve stable occlusion for Complete denture patients.