An up to 20-year retrospective study of 4-unit fixed dental prostheses for the replacement of 2 missing adjacent teeth.
OBJECTIVE
This study evaluated treatment outcomes of 4-unit porcelain-fused-to-gold fixed dental prostheses (FDPs) replacing 2 adjacent missing teeth.


METHODS
A total of 102 FDPs made in an undergraduate university clinic for 73 patients were evaluated for up to 20 years, with a mean survival follow-up time of 11.4 years. All patients were offered an oral health maintenance program. Treatment failures were divided into irreversible (loss of FDPs/finish line involved) or reversible (FDPs and finish line intact after conservative treatment) complications and into biologic and technical/patient-related failures.


RESULTS
The Kaplan-Meier overall estimated survival rate was 68.3% at year 20. There was a statistically significant difference (P = .007) between the survival rates in the maxilla for the vital group (73.8%) and those for the root canal-treated group (25.1%). Comparing the survival rate in the root canal-treated group for the restorations in the maxilla (25.1%) versus the mandible (66.8%), a statistically significant difference (P = .011) was found. The main reason for irreversible failure was caries (32.0%).


CONCLUSIONS
The estimated successful outcome of 4-unit FDPs over an up to 20-year period is considered favorable and should be compared with the survival rates of other treatment options for the replacement of 2 adjacent teeth. Occurrence of a previously reversible complication appears to be a predictive factor for an irreversible complication later on. A reversible complication within the first 2 years will lead to an early irreversible complication.
Centre for Special Care, PaeCaMed Research, Unit of Gnathology and Temporomandibular Disorders, Dental School, Faculty of Medicine and Health Sciences, Ghent University, Belgium. hein.debacker@skynet.be
Hein
H
De Backer
Georges
G
Van Maele
Nathalie
N
De Moor
Linda
L
Van den Berghe
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000044:Dental Abutments; D003731:Dental Caries / Q000150:complications; D003776:Dental Porcelain / Q000737:chemistry; D019232:Dental Restoration Failure; D003779:Denture Design; D003781:Denture Retention; D003830:Denture, Partial, Fixed; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008297:Male; D016876:Metal Ceramic Alloys / Q000737:chemistry; D008875:Middle Aged; D010510:Periodontal Diseases / Q000150:complications; D011176:Post and Core Technique; D012189:Retrospective Studies; D016019:Survival Analysis; D019553:Tooth, Nonvital / Q000628:therapy; D016896:Treatment Outcome; D015036:Zinc Phosphate Cement / Q000737:chemistry
D006047:Gold Alloys; D016876:Metal Ceramic Alloys; D003776:Dental Porcelain; D015036:Zinc Phosphate Cement