Tooth-Supported Removable Dentures PDF

# Tooth-Supported Removable Dentures Assoc. Prof. Dr. Simge Taşın ## Definitions - Overdenture - Overlay Dentures - Superposition appliances - Telescopic Prosthesis - Hybrid Prosthesis ## Introduction The standard treatment for edentulous patients is removable complete dentures. However, the pa...

# Tooth-Supported Removable Dentures Assoc. Prof. Dr. Simge Taşın ## Definitions - Overdenture - Overlay Dentures - Superposition appliances - Telescopic Prosthesis - Hybrid Prosthesis ## Introduction The standard treatment for edentulous patients is removable complete dentures. However, the patient with complete dentures experiences: * Loss of dental proprioception * Progressive alveolar bone resorption * Changes such as the transfer of all occlusal forces from the teeth to the oral mucosa. * The most depressive outcome is the loss of self-confidence of the patient. * In addition, full denture users reported loss of oral function as a result of losing retention and stability in their prosthesis over time. Complete denture candidates usually have few natural teeth in their mouths. In such patients, by applying the basic principles of "conservative prosthetic treatment", a seemingly inevitable completely edentulous condition can be avoided and patients can be successfully rehabilitated using the procedure called "overdenture treatment". Overdenture prosthesis are removable dentures in which the denture base covers one or more teeth, teeth roots, or implants. ## Overdenture prosthesis Overdenture prosthesis are complete (total Overdenture) or partial (Removable Partial Overdenture) dentures fabricated on supporting teeth (left in the mouth with preparation), roots, or implants. ## Advantages of Overdenture prosthesis - Increases the support, retention and stability of the prosthesis, - With the increase in retention and stability, the patient's adaptation to the prosthesis becomes easier, - Horizontal forces and torque forces transmitted to the alveolar bone decrease, - The continuity of the proprioceptive response is ensured, - The presence of teeth relieves the patient psychologically, - A satisfactory aesthetic is obtained in cases with excessively resorbed crest, - In case of loss of support teeth, it can be easily converted to a total denture. ## Disadvantages of Overdenture prosthesis - Additional treatments and attachments need to be used for overdenture support may increase the cost. - Their construction takes more time than conventional prosthesis types. - Copings have a risk of falling, abrasion and loss. There may be a risk of breakage, wear or rupture of the attachments used. - Thinning denture base may break due to increased muscle strength and supporting teeth number. - Due to its complicated structure, patients may experience difficulty in using and oral hygiene problems. Therefore, it should be applied to people with good oral hygiene. - Regular patient check-up is required. - This should be taken into account in physically handicapped patients. Though, it is a very advantageous treatment option compared to conventional full dentures, appropriate case selection is also important. ## Indications for Overdenture treatment - Single complete dentures - Cleft palate, surgical defect cases, trauma patients - Cases of hypodontia - Cases of extreme wear where the vertical dimension is decreased - Where patient adaptation may be a problem in a lower complete denture case - Cases where support teeth are risky to support removable partial dentures - In patients who care about oral hygiene and take care to preserve their existing teeth ## Contraindications for Overdenture treatment - In patients who cannot maintain oral hygiene due to physical and mental disability and who are at risk of swallowing the removable prosthesis - In cases that have contraindications to root canal treatment - Excessively curved roots of teeth intended to be used - Conditions where there is not enough interocclusal distance - If the existing Class II or Class III bone configurations prevent the aesthetic alignment of the anterior teeth - In patients who cannot afford the additional cost ## Overdenture Classification - **According to the time of construction** - Immediate - Interim - Permanent - **According to type of support** - Teeth-supported - Implants - Supported - **According to use of coping** - No coping - Coping - Telescopic Attachment - **According to base material** - Acrylic base - Metal base ## Immediate Overdenture These are prostheses that can be prepared before oral preparations (extraction, preparation, etc.) and delivered to the patient immediately after preparations. ## Temporary Overdenture Used for patients in transitional or preparation phase until permanent overdenture is done. The old partial denture of the patient can be replaced, the denture can be used by extending it and adding teeth. ## Permanent Overdenture They are the final prostheses delivered to the patient after clinical and laboratory stages. It can be made entirely of acrylic or have a metal substructure. ## Supporting Teeth Without Coping - Selected abutments are shortened to a coronal height of 2 to 3 mm. - It is then contoured to a convex or dome-shaped surface. - Most teeth require endodontic treatment and the tooth is prepared for an amalgam or composite restoration at the final stage. Advantages: - It is the cheapest option - In emergencies, treatment can be modified. - There is more flexibility in formulating the treatment plan ## Supporting Teeth with Coping Coping is a cover for the exposed tooth surface. A cast metal coping with a dome-shaped surface and a chamfer finish line at the gingival margin is fabricated and cemented, - Short - Long (requires larger crown/tooth) ## Supporting Teeth with Attachments - Attachments are small precision devices. - The aim is to improve the retention of the denture base. - Most attachments are fixed to the abutment by casting coping. - It consists of two parts: - Male - Female Disadvantages: - Additional time and expense - Difficult to build and repair - Requires careful manipulation by the patient, NOT recommended for mentally and physically disabled ## Rigid Attachment -Does not allow movement of the denture base -Adequate retention must be ensured -Can induce more torque on the abutment ## Flexible Attachment -Provides some control -Induces less torque in abutments ## Examination and Diagnosis * **Anamnesis** * Medical * Dental * **Clinical Examination** * Periodontal condition * Endodontic evaluation * Caries activity * Bone support * Number and position of supporting structures * Axial slope and form of supporting teeth * Chewing load and condition of the antagonist dentition * Denture design * **Radiography** * Panoramic * Periapical ## Treatment Plan and Course After a correct diagnosis, before starting the treatment, the patient's expectations for prosthesis should be learned, the patient should be informed about overdenture treatment and patient is to be motivated. If necessary, periodontal and endodontic treatments should be completed following surgical procedures. If necessary, an immediate overdenture is performed, and then the permanent prosthesis should be made. *Selection and preparation of supporting structures.* *Fabrication of copings.* *Making complete dentures on the supporting structures that have been restored.* ## Periodontal Condition of Supporting Teeth * Amount of supporting alveolar bone (primary importance, appropriate crown/root ratio, resistance to incoming forces) * Manageable periodontal pocket depth * Sufficient attached gingiva Unless minimal pocket depth and adequate attached gingiva are achieved, periodontal disease is likely to persist until teeth are lost. ## Position of Supporting Teeth Teeth where occlusal forces have the greatest destructive potential should be kept in the mouth. In edentulous patients, the anterior portion of both dental arches is very sensitive to resorption. For this reason, it is advantageous to keep canines or premolars in these areas. The maxillary canines protect the maxillary edentulous crest from excessive stress generated by the mandibular natural teeth during function. Mandibular teeth are more important because of the difficulty in stabilizing the lower prosthesis and the degree of resorption of the mandibular crest. Mandibular canines are often the last teeth to be lost and their position in the arch is strategic to support and stabilize an overdenture. An isolated tooth may be an acceptable abutment for an overdenture when there are no teeth on either side of the dental arch. A single molar can greatly contribute to the stability of the mandibular prosthesis. Preserving the teeth in both dental arches helps maintain the occlusal vertical dimension created by the dentures. Retaining a canine and a second premolar instead of a canine and a first premolar creates a larger area of support. This is more important in cases with natural teeth in the opposing jaw. ## Path of Insertion Remaining teeth may have an undercut, especially in the labial contour. If the lingual area has undercuts also, it may be difficult to provide the path of insertion. In order not to damage the tissue around the teeth, relief should be made on the parts of the prosthesis facing the tissue. Deep undercut areas can be modified to leave the base exposed. ## Endodontic Evaluation Root canal treatment is often required in order to shorten the clinical crown length of a tooth so that it remains below the prosthesis. In such cases, single-canal teeth are clearly more advantageous in terms of treatment success, cost and effort. It is also easy to modify the prosthesis as a result of the loss of the tooth in the future. The exception is a vital molar, which can be restored with a low-level thin coping without the need for root canal treatment. This situation is more advantageous in terms of retention. ## Preparation of Supporting Teeth There are 4 types of preparations for the use of primary coping: 1. Short preparation (For Devital teeth) * Short preparation for bare root supports * Short preparation for short copings 2. Medium-short preparation (For Devital teeth) * Medium-short preparation for bare root supports * Medium-short preparation for copings 3. Medium preparation (For devital and vital teeth) 4. Long preparation (For vital teeth) * Long preparation in which an acrylic resin prosthesis is applied as a secondary coping on the primary coping * Long primary coping preparation for use with metal secondary copings ## Coping Types I. Primary copings: Copings prepared to fit on the prepared support. 1. Long copings (6-8 mm.) 2. Medium copings (4-6 mm.) 3. Medium-short copings (2-4 mm.) 4. Short copings (1-2 mm.) II. Secondary copings: These are copings that sit on the primary coping. ## Preparation of Prostheses After the preparations of the supporting structures are completed, it is time to start the denture making procedure. Impressions are taken with an acrylic tray and an elastomeric impression material. The model is obtained. Temporary base plates and jaw relations are determined. Teeth alignment is complete. There may be problems in the placement of the teeth on the copings. Usually, small reductions are made from the back of the teeth to be placed here. Prosthesis is completed after modeling and acrylic fabricating then is adapted to the patient's mouth by using pressure pastes. ## Assessment Criteria for Overdenture Success They are the same as those used to evaluate a tissue-supported prosthesis. * Is support, retention and stability adequate? * Is the patient comfortable and satisfied? * Are the aesthetic, phonetic and functional properties of the prosthesis sufficient? * Are occlusal contacts compatible with mandible movements? ## Periapical Tissue Evaluation The periapical tissue of a support tooth for overdenture is evaluated in the same way as natural teeth.. The supporting tooth must have a radiographically healthy lamina dura. If there is an apical infection, it should have healed after root canal treatment. A tooth with previous root canal treatment should be able to maintain a successful prognosis. ## Clinical Crown Evaluation If no signs of caries are detected, it is considered successful. Remaining teeth should be prepared, contoured and polished to allow easy removal of the denture. After the canal orifice is closed with amalgam or composite resin, the support tooth can be used directly or covered with a thin coping. ## Cast Gold Coping A cast gold coping with a root canal post is only used if the tooth structure cannot provide sufficient contour to be acceptable with an amalgam restoration. ## Long-Term Success The long-term successful use of overdenture treatment primarily depends on the patient's protection of supporting structures. After the overdenture is applied to the patient's mouth, the natural stimulation and cleaning of the supporting tissues decreases. This functional reduction results in loss of keratinization of the surrounding supporting tissues and an increased likelihood of trauma. For this reason, prosthetic treatment cannot be considered complete without informing the patient about oral hygiene and prosthetic hygiene. ## Hygiene Instructions For this purpose, patients are advised to: * brush around the supporting structures by teaching appropriate tooth brushing techniques. * Teaching appropriate interproximal brushes usage along with dental floss * brush the oral tissues with a soft brush. * rinse with 0.O25% fluorine or 0.1-0.2% chlorhexidine mouthwash in cases where mechanical cleaning is not sufficient. * remove prostheses at night, brush, and keep in a suitable cleaning solution every 2-3 weeks. ## Example Cases - A collage of images showing the before and after of an overdenture treatment with a statement about the case. - A collage of images showing different types of attachments. - A collage of images showing a lower complete denture case. - A collage of images showing a case with a maxillary edentulous crest. - A collage of images showing a pre-treatment and post-treatment case. - A collage of impressions, teeth try-in, finished prosthesis. ## References - Özneli, R. *Diş üstü protezlerde schubiger ataşman dizaynının modifiye kullanımı: Olgu sunumu*. Atatürk Üniv. Diş Hek. Fak. Derg., 2016. - Lord, J. L. *The overdenture: Patient selection, use of copings, and follow-up evaluation*. J Prosthet Dent., 1974. - Preiskel, H. W. *Overdentures Made Easy: A Guide to Implant and Root Supported Prostheses*. Quintessence Publishing, 2018. - Prof. Dr. Oğuz OZAN. *Overdenture prostheses lecture notes*. ## Image A picture of a painting by Franz von Stuck- Falling Stars (1912) showing a couple sitting in a field looking up at a starry night sky. The couple are silhouetted against the dark sky and there are a few bright stars in the sky. Several comets are flying across the sky in the painting.