Scored tablets can be divided into equal halves for individual treatment of patients. However, the relationships between scored shapes and tablet characteristics such as the dividing strength, halving equality, and breaking strength are poorly understood. The purpose of this study was to simulate the mechanical stress distribution of scored tablets by using the finite element method (FEM). A runnel of triangle pole on the top surface of flat tablets was fabricated as the score shape. The depth and angle of the scores were selected as design variables. Elastic parameters such as a Young's modulus and a Poisson ratio for the model powder bed were measured. FEM simulation was then applied to the scored tablets, represented as a continuum elastic model. Stress distributions in the inner structure of the tablets were simulated after applying external force. The adequacy of the simulation was evaluated in experiments using scored tablets. As a result, we observed a relatively good agreement between the FEM simulation and the experiments, suggesting that FEM simulation is advantageous for designing scored tablets.

The mechanical strain distribution of scored tablets was simulated using the finite element method (FEM). The score was fabricated as a triangular runnel with the pole on the top surface of flat tablets. The effect of diametral compression on the tablet surface strain was evaluated by changing the angle between the scored line and the diametral compression axis. Ten types of granules were prepared according to an extreme vertices design. Young's modulus and the Poisson ratio for the model powder bed were measured as elastic parameters. The FEM simulation was then applied to the scored tablets represented as a continuous elastic model. Strain distributions in the inner structure of the tablets were simulated after the application of external force. The maximum principal strain (ε) value was obtained with tablets containing a large amount of corn starch, in all scored line positions. In contrast, the ε value of the tablets containing a large amount of microcrystalline cellulose was minimal. The adequacy of the simulation was evaluated by experiments with scored tablets. The results indicated a fairly good agreement between the FEM simulation and experiments. Moreover, it was found that the ε value correlated negatively with the value of tablet hardness. These results suggest that the FEM simulation was advantageous for designing scored tablets.

The purpose of this study was to determine the density distribution of scored and round-faced tablets using synchrotron X-ray computed tomography. The tablets were made by direct compression of standard formulations. The density distribution of scored ‰at-faced tablets was uniform in the whole cross-sectional image. However, the tablet formulated using microcrystalline cellulose (MCC) was very dense at the tip of the score only. It is caused by the poor ‰uid-ity of MCC particles. In the case of round-faced tablets, the density in the central section of the tablet was relatively low, compared with those of peripheral areas. These observations correlated well with the results obtained by theˆnite element method simulation using appropriate material models.