The purpose of this study was to evaluate the removable partial denture prescriptions including surveyed crowns and design of component parts sent to the laboratory technician. A total of 351 cases with prescription forms and master cast in maxillary and mandibular semi-edentulous situations collected from dental laboratory by random sampling were selected for this study. The evaluation and study observed here involved the classification of edentulous situations, status of abutment splinting, form of rest seats and guiding plane of surveyed crows, location of maxillary major connectors and tripodig marks on the master casts. Removable partial denture prescriptions contained (1) general request (upper and lower cast framework), (2) types of metal, (3) location of retainer (retention, lingual bracing, rest area, guiding plane surface), (4) location and type of major connector, (5) relief area and amount, (6) and other specific instructions. The following informations based on the classified groups such as Group Ⅰ was those cases sent with no real prescriptions. They say, "make a partial." No prescriptions, no thought beforehand, Group Ⅱ was those cases sent with a minimal prescriptions. They say "make a partial with clasps no……. May be some preparations, usually inadequate. Group Ⅲ was those cases sent with a moderately good prescription. Adequate but could be much better. No tripoding but it tell what clasps go where. Still not good prescriptions. Group Ⅳ was good cases, tripoded with adequate prescriptions and a prescription with exactly describes what is expected from the laboratory. The analyzed results were as follows: 1. The normal form of rest seats and guiding plane of surveyed crowns in Class. Ⅰ and Class. Ⅱ edentulous situations on the maxillary cast were observed 31.9% and 27.89%, respectively. The abutment teeth and retainer without occlusal rests of Class Ⅰ and Class Ⅱ were showed 11.58% and 8.86%, respectively. In mandibular cases, the normal form of rest seats and guiding plane of surveyed crowns showed 27.54% and 8.82% in Class Ⅰ and Class Ⅱ situation. The abutment teeth and retainer without rest seats were showed 15.19%, respectively. 2. The splinted surveyed crowns of Class Ⅰ and Class Ⅱ maxillary edentulous situations in distal extension cases were showed 34.51% and 28.85%, but 28.52% and 10.29%, respectively. 3. The location and type of maxillary major connector delineated on the master cast were 66 cases (44.89%).
4. The results of 351 cases were classified as Group Ⅰ 146(41.59%), Group Ⅱ 115(32.76%), Group Ⅲ 57(16.23%), and Group Ⅳ 33(9.48%). 5. The delineation of abutment tooth for clasping were 176 cases (50.14%) among total of 351 cases. 6. The delineation of height of contour line were showed 45 cases (12.8%) in GroupⅡ, 14 cases (3.98%) in Group Ⅲ and 33 cases (9.40%) in Group Ⅳ with total 92 cases (26.21%). 7. In surveying procedure, the delineation of tripoding marks and reference line were showed 17 cases (4.84%).
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