A piston assembly for an internal combustion engine is provided. The piston assembly includes a piston crown including an upper surface defining a bowl region, a side portion and a lower surface, a piston skirt depending from the side portion of the piston crown, a sensor, at least partially coated by a visualization material, disposed within the piston crown at a location proximate to the bowl region, and a sensor data telemetry system coupled to the sensor. Methods for manufacturing a piston assembly for an internal combustion engine are also provided.