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Title Which Implant Overdenture has a Better Prognosis in Edentulous Maxilla: 4 Implant or 6 Implant Supported Overdenture?
Clinical Question In a 60-year-old male with an edentulous maxilla and opposing mandibular natural teeth which treatment option has a better prognosis for the patient: A 4 implant supported maxillary overdenture or a 6 implant supported maxillary overdenture?
Clinical Bottom Line At this time there are no studies that show how many implants are indicated for an edentulous maxilla. However, some studies suggest that both 4 and 6 implant supported maxillary overdentures have similar prognosis. They both have great implant survival rates, minimal marginal bone loss, and improved esthetics and oral hygiene.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 23062145Roccuzzo/2012Out of 3156 titles obtained from pubmed 11 full text articles were selected. These articles were all RCTs with at least 12 months follow up, in fully edentulous patients over 18 years of age.Systematic review of randomized trials
Key resultsThere are no studies indicating how many implants are needed to support a maxillary overdenture. Some studies suggest “patient satisfaction or function of prosthesis are not dependent on the number of implants or type of attachment.”
#2) 23320877Slot/201250 edentulous patients that have been edentulous for at least one year, have sufficient bone for implant placement and are suffering from lack of retention and stability of their dentures.Randomized Controlled Trial
Key resultsImplant survival rate was 100% for the 4 implant overdenture group and 99.3% for the 6 implant overdenture group. The overdenture survival rate was 100% for both groups. The mean loss of marginal bone was 0.24 +/-0.32 mm in the 4 implants group and 0.25 +/- 0.29 in the 6 implant group. Patient overall satisfaction scores were improved (p<0.05) significantly between pre-treatment and post-treatment assessment.
Evidence Search (("maxilla"[MeSH Terms] OR "maxilla"[All Fields] OR "maxillary"[All Fields]) AND supported[All Fields] AND ("denture, overlay"[MeSH Terms] OR ("denture"[All Fields] AND "overlay"[All Fields]) OR "overlay denture"[All Fields] OR "overdentures"[All Fields])) AND Randomized Controlled Trial[ptyp] ("Dental Implants"[Mesh] AND "Jaw, Edentulous"[Mesh]) AND "Denture, Overlay"[Mesh] AND systematic[sb]
Comments on
The Evidence
Slot’s article was a randomized controlled trial done on 50 healthy edentulous patients. All patients were similar at start. Out of 50 patients 1 dropped out but overall this study had more than 80% completion rate. Groups were treated the same and adequate follow up was done. Patients were compliant and there were no competing interest. Roccuzzo’s article was a systematic review of 11 RCT articles, including Slot’s, of edentulous maxilla and mandible. Patients over the age of 18 were selected and followed for at least 12 months. The focus of the article was implant loss, peri-implant bone loss, and patient satisfaction.
Applicability According to Roccozzo no studies were found to support the number of implants indicated for maxillary overdentures. Roccozzo also stated that Slot used different designs in his study, which weaken the evidence. He concludes that more research needs to be done in this field. In Slot’s article it was shown that both 4 and 6 implant supported maxillary overdentures improve retention and stability in comparison to conventional dentures. They both also improved esthetics, speech, and hygiene. Maxillary overdentures supported on 4 or 6 implants have “high implant survival, healthy peri-implant tissues and high patients’ satisfaction.”Overdentures supported by 4 implants are more cost-effective.
Specialty/Discipline (Periodontics) (Prosthodontics)
Keywords Edentulous maxilla, overdenture, implants.
ID# 2692
Date of submission: 03/24/2014spacer
E-mail seddighzadeh@livemail.uthscsa.edu
Author Brad Seddighzadeh
Co-author(s) e-mail
Faculty mentor/Co-author Stephan J. Haney, DDS
Faculty mentor/Co-author e-mail haneys2@uthscsa.edu
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