For someone who is 17 years old, who is 17.7 centimeters long and 13 centimeters thick, what is the estimate of the final length in development?

To estimate the final length in development for someone based on age and growth metrics, various factors need to be considered. Most notably, the growth patterns of individuals can vary significantly based on genetics, sex, and other factors. However, the figures you've provided (17.7 centimeters long and 13 centimeters thick) seem uncommonly small for a 17-year-old. Typically, a 17-year-old human's height isn't measured in centimeters that way, indicating that they could refer instead to some other measurement rather than human height. If you are indeed referring to height, it usually falls within the range of 150 cm to 190 cm for most individuals of that age. If you're referring to a different context (such as growth in animals, plants, or objects), please clarify. In general, if assessing growth potential or final height, it's often necessary to refer to growth charts, skeletal maturity (as indicated by X-rays of growth plates), and family patterns. Without more context, I'm unable to provide a precise estimation. If you have more detailed information or context regarding the entity being measured, please provide it for a more accurate assessment!