Dr. Mentz has been a leader in plastic surgery for men. He developed and published "abdominal etching" as a specialized liposuction technique performed to create the "six pack" abdomen in 1991. He later established a modified version so that regular guys could get "athletic abs" through special liposculpting techniques in 1995. He has recently introduced "pectoral etching", which utilizes the same philosophy of detailed liposuction sculpting to achieve a more masculine chest in 2003. Also in 2003, he introducted puncture removal of gynecomastia (overdeveloped breast glands in men most often removed through larger incisions). Pectoral implants are sometimes used to augment the pectoral muscles.

In addition Dr. Mentz's credentials in men's athletic contouring, he has special credentials in facial surgery. He has written regarding facelifts (rhytidectomy), necklifts, eyelids (blepharoplasty), rhinoplasty (nose job), and fat grafting. Dr. Mentz's reputation as a leader in this field of aesthetic plastic surgery for men has made him a highly sought after writer and speaker.