This paper will start by mentioning very briefly previous results reported recently for mechanical sensors based on embedding a rectangular-lattice photonic crystal into the core of a standard monomode optical fiber. The next step will be to introduce and evaluate another mechanical sensor based on embedding a triangular-lattice photonic crystal into the core of the optical fiber. We will argue that such sensors (i.e., which embed photonic crystals into the core of optical fibers), are highly sensitive to mechanical deformations. Finally, we will estimate the sensitivity of the mechanical sensor which relies on a triangular-lattice photonic crystal, and compare it with that of a mechanical sensor which uses a rectangular-lattice photonic crystal. The main conclusion is that the triangular-based sensor is 22% more sensitive (than the rectangular-based one), while future directions of research will end the paper.