Jump to content

Overdenture

Edit links
From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Sphenoid15 (talk | contribs) at 14:07, 22 November 2018 (added 'types of abutment' sub-heading). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Overdenture resting on implants on a plastic model

Overdenture is any removable dental prosthesis that covers and rests on one or more remaining natural teeth, the roots of natural teeth, and/or dental implants.[1] It is one of the most practical measures used in preventive dentistry. Overdentures can be either tooth supported (conventional / immediate) or implant supported. It is found to help in the preservation of alveolar bone and delay the process of complete edentulism.[2]

Alternative Terminologies

Types

Overdentures can be classified into 2 categories, depending on the types of abutment providing support:

Types of Abutment

Tooth-supported

This type of overdenture overlies natural tooth structures. Frequently, elective root canal treatment and coronal modification are carried out on the teeth that are used as abutments. This means that the pulpal tissues and crowns of the natural teeth are removed, followed by contouring of the tooth structure above the gum. This allows even distribution of occlusal stress onto the abutment teeth and soft tissues. [3] Other than that, retention of natural teeth in the jaw helps preserve bone by delaying the process of bone resorption in the jaw. [4]

Selection of abutment teeth depends on a few factors including:[1]

  • Location

To provide adequate support, there should be one abutment tooth per quadrant and the abutment should ideally be a canine.

  • Prognosis

The teeth selected to provide support should be healthy i.e. not decayed and no/ manageable gum disease, thus ensuring long term retention in the jaw.

  • Feasibility of endodontic treatment

Most of the time, the crown of the abutment teeth has to be removed to allow space for placement of overdenture without interfering the bite. Therefore, the pulp has to be removed. If the root canals of the abutment teeth are obliterated, endodontic treatment is not required. Teeth with non-negotiable root canals should not be selected as abutments.

Implant-supported

Edentulous patients with sufficient amount of bony ridge on their jaws can opt for implant supported overdenture.[3] This type of over denture gains support from both the dental implants and intraoral tissues. Having implant-supported overdenture provides better stability of prosthesis and reduce bone resorption.[5] However, a conventional complete denture can be considered as an alternative due to less treatment time needed.[6]

Types of Attachment System

Overdentures can be further classified according to the types of attachment system used.[7] The attachment systems function to enhance retention and stability of the overdenture.[8] Currently there isn't enough evidence to advocate a particular system and hence technical aspects are the main consideration when choosing it.[8] Other factors include the inter-arch space available and operator’s skills.[2]

Stud attachments

This is the oldest system available and consists of a male (stud) and female (housing) component.[9] It connects the over denture to the individual abutment.[10]

Examples of stud attachments include:

  • O-rings attachment:  This system consists of a metal abutment analogue and a metal O-ring fitted with silicone ring.
  • Extra-radicular attachment (ERA): This system is deemed most suitable for parallel implant abutments.
  • Ball attachment: This is the simplest system, consisting of a ball and a socket. The ball (male unit) is made on the implant abutment while the socket (female unit) is incorporated on the fitting surface of the overdenture.
  • Locator (self-aligning) attachment: This is the least commonly used stud attachment and is usually indicated when the implant abutments are non-parallel to each other.

Bars and clips

Bars function to connect the over denture to the splinted abutments. A clip or sleeve is then placed over the bar to hold the overdenture in place. Depending on their resiliency, bars can be made either a bar joint (resilient) or a bar unit (non-resilient/ rigid). Overall, this is the most popular attachment system due to its ability to stabilise overdenture and relatively higher wear resistance.

Magnets

This system consists of a magnet incorporated on the fitting surface of the overdenture and the magnet keeper fixed to the implant abutments. It is considered to be resilient and less retentive than the ball attachment, allowing movement of overdenture.

Telescopic

This system is more commonly used in overdentures supported by natural teeth rather than implants. It consists of a primary coping cemented to the abutments and a secondaring coping, which is incorporated on the overdenture, to fit over the primary coping. Hence, it is also known as double crown, a crown and sleeve coping or Konuskrone.

Indications

Retention and Stability

- If prescribing a removable prosthesis and there is limited remaining firm teeth in the dentition an overdenture may aid in retention and stability compared to that of a conventional removable prosthesis[11].

Preventative Dentistry

- The use of an overdenture delays the process of leaving the patient completely edentulous and assists in the preservation of bone[11].

- As a main priority for many dentists and patients, preventative dentistry is a reason for prescribing an overdenture as it retains the natural teeth for longer[12].

Patient Anatomy

- Overdentures can be useful for patients with a severe ridge defect or bone resorption[13].

- Patients who have unfavourable tongue positions and muscle attachment for a conventional removable prosthesis could find that an overdenture has increased retention and stability[12].

- If the patient has a superficially placed mental nerve, then the preferential choice of treatment may be to leave certain teeth in place in order to prevent damage to the nerve and prescribe an overdenture for any aesthetic needs[13].

Protection of Root Canal Filling

- An overdenture can be prescribed for a patient who has just had a root canal treatment completed to protect the coronal seal of the tooth if they are waiting to have fixed prosthodontics carried out on the tooth.

Advantages

  • Preservation of alveolar bone[14]
  • Providing stability and retention
  • Improving masticatory efficiency[15]

Disadvantages

Research & evidence

A 10 year observational period found that implants which supported overdentures in the mandible had a survival rate ranging from 91.7% to 100%.[16] Furthermore, implant survival rates with respect to their attachment system were found to be best for the ball type attachment which was an average of 95.8 - 97.5%, followed by the bar and magnet ranging from 96.2 - 100% , and 91.7% respectively.[17]

References

  1. ^ Glossary of Prosthodontics. Vol. Volume 117. May 2017. {{cite book}}: |volume= has extra text (help); Cite has empty unknown parameter: |dead-url= (help)
  2. ^ Samra, Rupandeep Kaur; Bhide, Shreenivas Vasant; Goyal, Chhavi; Kaur, Taranjit (2015-01-01). "Tooth supported overdenture: A concept overshadowed but not yet forgotten!". Journal of Oral Research and Review. 7 (1).
  3. ^ a b Bansal, Siddharth; Aras, Meena A.; Chitre, Vidya (December 2014). "Tooth Supported Overdenture Retained with Custom Attachments: A Case Report". Journal of Indian Prosthodontic Society. 14 (Suppl 1): 283–286. doi:10.1007/s13191-013-0340-0. ISSN 0972-4052. PMC 4502008. PMID 26199532.{{cite journal}}: CS1 maint: PMC format (link)
  4. ^ Samra, RupandeepKaur; Bhide, ShreenivasVasant; Goyal, Chhavi; Kaur, Taranjit (2015). "Tooth supported overdenture: A concept overshadowed but not yet forgotten!". Journal of Oral Research and Review. 7 (1): 16. doi:10.4103/2249-4987.160172. ISSN 2249-4987.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  5. ^ Lambade, Dipti; Lambade, Pravin; Gundawar, Sham (May 2015). "Implant supported mandibular overdenture: a viable treatment option for edentulous mandible". Journal of clinical and diagnostic research: JCDR. 8 (5): ZD04–06. doi:10.7860/JCDR/2014/7711.4332. ISSN 2249-782X. PMC 4080073. PMID 24995252.{{cite journal}}: CS1 maint: PMC format (link)
  6. ^ Visser, Anita; Meijer, Henny J. A.; Raghoebar, Gerry M.; Vissink, Arjan (May 2006). "Implant-retained mandibular overdentures versus conventional dentures: 10 years of care and aftercare". The International Journal of Prosthodontics. 19 (3): 271–278. ISSN 0893-2174. PMID 16752625.
  7. ^ Prasad, DKrishna; Prasad, DAnupama; Buch, Manan (2014). "Selection of attachment systems in fabricating an implant supported overdenture". Journal of Dental Implants. 4 (2): 176. doi:10.4103/0974-6781.140905. ISSN 0974-6781.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  8. ^ a b Daou, Elie E. (April 2013). "Stud attachments for the mandibular implant-retained overdentures: Prosthetic complications. A literature review". The Saudi Dental Journal. 25 (2): 53–60. doi:10.1016/j.sdentj.2012.12.003. ISSN 1013-9052. PMC 3723078. PMID 23960557.{{cite journal}}: CS1 maint: PMC format (link)
  9. ^ Prasad, DKrishna; Prasad, DAnupama; Buch, Manan (2014). "Selection of attachment systems in fabricating an implant supported overdenture". Journal of Dental Implants. 4 (2): 176. doi:10.4103/0974-6781.140905. ISSN 0974-6781.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  10. ^ Guttal, Satyabodh S.; Tavargeri, Anand K.; Nadiger, Ramesh K.; Thakur, Srinath L. (July 2011). "Use of an implant o-ring attachment for the tooth supported mandibular overdenture: a clinical report". European Journal of Dentistry. 5 (3): 331–336. ISSN 1305-7464. PMC 3137448. PMID 21769276.{{cite journal}}: CS1 maint: PMC format (link)
  11. ^ a b Samra, Rupandeep Kaur; Bhide, Shreenivas Vasant; Goyal, Chhavi; Kaur, Taranjit (2015-01-01). "Tooth supported overdenture: A concept overshadowed but not yet forgotten!". Journal of Oral Research and Review. 7 (1).
  12. ^ a b http://www.thejpd.org/pb/assets/raw/Health%20Advance/journals/ympr/Castillo.pdf. {{cite web}}: Cite has empty unknown parameter: |dead-url= (help); Missing or empty |title= (help)
  13. ^ a b Bansal, Siddharth; Aras, Meena A; Chitre, Vidya (2014-01-01). "Guidelines for treatment planning of mandibular implant overdenture". Journal of Dental Implants. 4 (1).
  14. ^ Dodge, Charles A. (1973-10). "Prevention of complete denture problems by use of "overdentures"". The Journal of Prosthetic Dentistry. 30 (4): 403–411. doi:10.1016/0022-3913(73)90161-3. ISSN 0022-3913. {{cite journal}}: Check date values in: |date= (help)
  15. ^ Awad, Manal A.; Feine, Jocelyne S. (1998-12). "Measuring patient satisfaction with mandibular prostheses". Community Dentistry and Oral Epidemiology. 26 (6): 400–405. doi:10.1111/j.1600-0528.1998.tb01978.x. ISSN 0301-5661. {{cite journal}}: Check date values in: |date= (help)
  16. ^ Kim, Ha-Young; Lee, Jeong-Yol; Shin, Sang-Wan; Bryant, S. Ross (2012-11). "Attachment systems for mandibular implant overdentures: a systematic review". The Journal of Advanced Prosthodontics. 4 (4): 197–203. doi:10.4047/jap.2012.4.4.197. ISSN 2005-7806. PMC 3517957. PMID 23236571. {{cite journal}}: Check date values in: |date= (help)
  17. ^ Kim, Ha-Young; Lee, Jeong-Yol; Shin, Sang-Wan; Bryant, S. Ross (2012-11). "Attachment systems for mandibular implant overdentures: a systematic review". The Journal of Advanced Prosthodontics. 4 (4): 197–203. doi:10.4047/jap.2012.4.4.197. ISSN 2005-7806. PMC 3517957. PMID 23236571. {{cite journal}}: Check date values in: |date= (help)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Overdenture&oldid=870116166"