Retrospective cohort analysis of maxillary overdentures retained by unsplinted implants.

STATEMENT OF PROBLEM: Implant therapy involving an unsplinted 2-implant-retained overdenture is well defined as a successful treatment for a patient with an edentulous mandible. However, a similar unsplinted implant therapy supporting a maxillary overdenture is not well characterized. PURPOSE: The purpose of this retrospective study was to evaluate maxillary overdentures retained by 4 unsplinted implants measuring implant survival, overdenture survival, and patient-reported outcomes. MATERIAL AND METHODS: Participants who had received an unsplinted implant-retained maxillary overdenture were included in the study. Participants presented for one denture recall appointment, during which comprehensive examination, including radiographs, was performed and clinical findings were recorded. Participants also completed the Oral Health Impact Profile-49 (OHIP-49) and a 20-item visual analog scale (VAS) satisfaction questionnaire. Nonparametric statistical tests were used to compare OHIP-49 and VAS scores across age, sex, time since overdenture insertion, mandibular dental status, smoking status, maxillary mucosal health, and overdenture hygiene. RESULTS: For the 44 participants, 3 of 4 implants failed in 1 individual. The cumulative implant survival rate was 98% (97.7% patient level). No prosthetic failures (that is, overdenture replacement) occurred, indicating a 100% prosthesis survival rate. The mean ±standard deviation OHIP-49 severity score was 23.6 ±26.0, and the mean ±standard deviation total VAS score was 179.2 ±29.4. Increased age was associated with lower OHIP-49 severity score (P=.036), and participants with unhealthy oral mucosa or denture stomatitis demonstrated significantly higher OHIP-49 severity scores (P=.003). CONCLUSIONS: In this retrospective evaluation, unsplinted implant-retained maxillary overdenture therapy was associated with high implant and prosthetic survival, as well as high patient satisfaction and quality of life. Age, sex, maxillary mucosal health, and mandibular dental status resulted in significant differences with respect to oral health-related quality of life and patient satisfaction, indicating that this treatment option may be ideal for certain patients.

The effect of implant-supported removable partial dentures on oral health quality of life.

PURPOSE: Removable partial dentures (RPDs) represent standard treatment for partial edentulism despite major shortcomings. To alleviate these shortcomings, endosseous implants provide support and stability as well as contribute to maintenance of alveolar bone. This prospective, within subject, time series study evaluated patient-based outcomes of RPDs compared to implant-supported removable partial dentures (ISRPDs). The study hypothesis was that the ISRPD would substantially improve oral health quality of life for patients. MATERIALS AND METHODS: Seventeen patients requesting new mandibular Kennedy I or II RPDs received one 6-mm dental implant in one or both of the posterior edentulous areas. After healing, conventional RPDs were fabricated and delivered. Twelve weeks later, second-stage surgery was performed, and ball abutments with Clix attachments were inserted, thereby converting the prostheses to ISRPDs. Oral health quality of life was evaluated using the 49-item Oral Health Impact Profile (OHIP-49) questionnaire. The OHIP-49 was administered prior to treatment (baseline), at 6 and 12 weeks following RPD delivery and at 6 and 12 weeks following ISRPD conversion. Radiographic evaluation was performed at 6 and 12 weeks following ISRPD conversion. In statistical analysis, a fixed-slope random intercept variance components model took account of the multiple observations per person over time. RESULTS: In 17 subjects, 29 of 30 implants survived. The failed implant was replaced without complications. Abutment complications were limited to one abutment loosening and one attachment replacement. Minor prosthodontic complications were recorded. The OHIP-49 score reduced by 11.8 points, on average, at 12 weeks following ISRPD conversion (P = 0.011). CONCLUSIONS: Patients reported improved oral health following conversion to an ISRPD from RPD. The ISRPD involving short implants is one treatment option that should be considered when treatment planning Kennedy Class I and II patients.

"Rules of 10"--guidelines for successful planning and treatment of mandibular edentulism using dental implants.

The three "Rules of 10" for treatment planning dental implant therapy in the edentulous mandible are designed to improve the success of both the endosseous implants and the prosthesis. These "rules" acknowledge and provide a method to control the mechanical environment, addressing factors affecting implant and prosthesis longevity, including magnitude of forces, resistance of the prosthesis against these forces, and the biology of bone and its ability to respond to loading environments. The rules specify that for any IRO or ISFP, there must be a minimum of 10 mm of alveolar dimension (inferior/superior) and a minimum of 10 mm of interocclusal (restorative) dimension measured from the soft-tissue ridge crest to the occlusal plane. Additionally, for an ISFP, the anterior/posterior distribution of implants must be greater than 10 mm. This article provides support in the literature for these rules and illustrates their application in the treatment of mandibular edentulism.