A surgical apparatus configured to be used in an ostomy procedure, comprising: an introducer configured for atraumatic insertion into a tissue opening; and a dilator including: an elongate body having a distal portion disposed within the introducer and being axially slidable in a proximal direction relative to the introducer from a first position to a second position; and at least one extension having a proximal end portion pivotably coupled to the elongate body and a distal end portion, wherein the distal end portion is rotatable in a proximal direction from a retracted state to an expanded state in response to movement of the dilator relative to the introducer from the first position to the second position, characterized in that: in the retracted state the at least one extension is disposed within the introducer with the distal end portion of the at least one extension in engagement with an inner wall of the introducer, and in the expanded state the at least one extension projects laterally outward from the distal portion of the elongate body with the distal end portion of the at least one extension out of engagement with the inner wall of the introducer; and the dilator includes a biasing member disposed within the elongate body, the biasing member biasing the at least one extension toward the expanded state. an introducer configured for atraumatic insertion into a tissue opening; and a dilator including: an elongate body having a distal portion disposed within the introducer and being axially slidable in a proximal direction relative to the introducer from a first position to a second position; and at least one extension having a proximal end portion pivotably coupled to the elongate body and a distal end portion, wherein the distal end portion is rotatable in a proximal direction from a retracted state to an expanded state in response to movement of the dilator relative to the introducer from the first position to the second position, an elongate body having a distal portion disposed within the introducer and being axially slidable in a proximal direction relative to the introducer from a first position to a second position; and at least one extension having a proximal end portion pivotably coupled to the elongate body and a distal end portion, wherein the distal end portion is rotatable in a proximal direction from a retracted state to an expanded state in response to movement of the dilator relative to the introducer from the first position to the second position, characterized in that: in the retracted state the at least one extension is disposed within the introducer with the distal end portion of the at least one extension in engagement with an inner wall of the introducer, and in the expanded state the at least one extension projects laterally outward from the distal portion of the elongate body with the distal end portion of the at least one extension out of engagement with the inner wall of the introducer; and the dilator includes a biasing member disposed within the elongate body, the biasing member biasing the at least one extension toward the expanded state. in the retracted state the at least one extension is disposed within the introducer with the distal end portion of the at least one extension in engagement with an inner wall of the introducer, and in the expanded state the at least one extension projects laterally outward from the distal portion of the elongate body with the distal end portion of the at least one extension out of engagement with the inner wall of the introducer; and the dilator includes a biasing member disposed within the elongate body, the biasing member biasing the at least one extension toward the expanded state.