PROSTHODONTICS - American College of Prosthodontists

30 Clmsjfication ofCom&e Edentulirm a iMcGa? et a1Figure 1. Radiograph with residual bonc height of 2 1 mmor greater measured at the least vertical height of themandible (Type I).procedures would be most appropriate for a patientwith a specific diagnosis.With the premise that complete edentulism hasdiffering degrees of severity, the committee sought toidentify and group the most significant diagnosticcriteria. The following criteria should help in applyingthe guidelines in a consistent manner.A Systematic Review of DiagnosticCriteria for the Edentulous PatientThe diagnostic criteria are organized by their objectivenature and not in their rank of significance.Because of variations in adaptive responses, certaincriteria are more significant than others5 However,objective criteria will allow for the most accurateapplication of the classification system and nieasurementof its efficacy. Objectivity also will providereliable outcome data and mechanisms for review bythird-party payers and peer-review panels. The diagnosticcriteria used in the classification system arelisted in the worksheet (Table 1).Figure 3. Radiograph with residual bone height of 11 to15 mm mcasured at the least vertical height of themandible (Type HI).Bone Height: Mandible onlyThe identification and measurement of residualbone height is the most easily quantified objectivecriterion for the mandibular edentulous ridge.6-g Inaddition, it represents a measurement of the chronicdebilitation associated with complete edcntulism inthe mandible. Despite the lack of a known etiology, ithas been establishcd that the loss of denturesupportingstructures does occur.6.8 Atwood‘s descriptionin 1971 of alveolar bone loss is still applicabletoday: “Chronic progressive, irreversible and disablingprocess probably of multifactoral origin. At thepresent time, the importance of various cofactors isunknown.” The continued decrease in bone volumeaffects: 1) denture-bearing area; 2) tissues remainingfor reconstruction; 3) facial muscle support/attachment;4) total facial heightg; and 5) ridge morphol-ogy.The results of a radiographic survey of residualbone height measurement are affected by the variationin the radiographic techniques and magnificationof panoramic machines of different manufacturers.To minimize variability in radiographictechniques, the measurement should be made on theradiograph at that portion of the mandible of the leastFigure 2. Radiograph with residual bone height of 16 to20 mm measured at the least vertical height of themandible (Type n).Figure 4. Radiograph with residual bone height of 10 mmor less measured at the least vertical height of the mandible(Type IV).2010 CDEL Re-recognition of the Specialty Report 149 of 279