Optical burst switching is a technique for transmitting several packets, through an optical transport network, by assembling them in large data containers, known as bursts. These bursts can be of variable length and are separated from their headers. The header, known as control packet, is sent through the network using a separate control channel, to reserve resources for the data burst that follows a short while later. This process demands efficient contention resolution, which can be done by optical buffering, wavelength conversion, deflection routing or burst dropping. The first three techniques, however, require additional resources in the network and/or nodes. In case additional resources are not available, or are scarce, it is beneficial to resolve contention using the burst dropping scheme. In this technique, whenever the transmission time of two or more bursts overlaps, one of the bursts needs to be dropped. In most of the cases, however, this overlap will only be partial, and it is more beneficial to drop only that part of the burst which overlaps with the other burst. This technique is known as segmentation-based dropping. This paper looks at burst dropping techniques in detail and compares their performance in terms of the burst blocking probabilities. Results show that segmentation-based dropping technique offers a significant improvement over the simple burst dropping technique.