Handling Of Resin Composites: A New Type Of Score S. Benedetti, R. Lorenzi, M. Anselmi, G. Dondi Dall’orologio (Dept. Of Dental Materials And Operative Dentistry, University Of Bologna, Italy) The classification of resin composites is often based on morphological or mechanical properties, however many specific features are required in an ideal composite material and, for a successful restorative procedure, the handling characteristics of a material are important as well. The handling is a combination of many properties that are connected between themselves. Jordan and Suzuki(1992) reported that a high viscosity “no slump” materials can be condensed and shaped with an high degree of control; the dental journals rated differently the clinical handling: Dental Advisor (1994) used a top score of 100 and products were evaluated between 72 an 98, Reality evaluated consistency and handling with a short comment, 3M company tested the ”ideal” rating, using as parameters viscosity, stickiness to instrument, flow and resistance to slump, with a score between 1 and 7, where the best score was 4, while the best score for ease of shaping, cavity/margin adaptation and packability was 7.   The aim of this study was to evaluate the handling of composite material using standardized dimensions of cavities, instrumentation and technique, with parameters that are not representing physical properties.   20 class I and 20 class II cavities, MO or OD, were prepared in extracted teeth mounted in a plaster base, with a 218, 3218 or 3224 diamond bur (Intensiv) using a speed of 100.000 r.p.m., cavities were prepared with 3.0 mm.of lingual-buccal diameter and 2.0 of depth, the proximal box was deep 3.5 mm. The measurement was done with a periodontal probe. 5 composites Herculite (H)(Kerr), Prisma TPH(P) (Dentsply), Pekafil (Pk)(Heraeus-Kulzer), Silux Plus (SP)(3M) and Z100 (Z)(3M) were used for filling 8 cavities, 4 class I and 4 class II for each one. A total etch technique and two bonding systems (Scotchbond 1-3M, Solid Bond –Heraeus Kulzer) were used according to manufacturer instructions; the composite was applied in three different layers, where the first was approximately 0.5 mm., with a stainless steel little spatula and a ball burnisher; any layer was light cured for 40 sec. from the occlusal surface. The restoration was finished with 4205 and 5205 diamond burs (Intensiv) and with Soflex discs and strips (3M). The procedure was performed by three operators. The parameters were: material control, occlusal adaptation, proximal adaptation, shaping, shape stability, finishing and polishing and any parameter was rated between 0 and 5 with a final score between 0 and 30.   The final score was respectively H 25/25/24, P 29/23/23, Pk 25/20/18, SP22/24/20, Z 22/26/21.   Scores were significatively different for all materials but H (P<0.05).   This study showed that composites demonstrated a large variation in handling rating and that there is a need for standardization of parameters of evaluation.