Implant apparatus and method for effecting a controlled heating of tissue within the region of dermis of skin. The heater implants are configured with a thermally insulative generally flat support functioning as a thermal barrier. One surface of this thermal barrier carries one or more polymerically encapsulated heater resistor segments with a lead assemblage exhibiting a 4-point topology. Each of the encapsulated heater segments may be thermally associated with a metal thermal spreader dimensioned in correspondence with and aligned with the heater segments. The implants are located within heating channels at the interface between skin dermis and the next adjacent subcutaneous tissue layer such that the heat spreaders are contactable with the lower region of dermis. During therapy a conformal heat sink is positioned against the skin above the implants and a slight tamponade is applied through the heat sink to assure a proper form of conduction heat transfer. An adjuvant may be employed to infiltrate dermis to significantly lower the thermal threshold transition temperature for dermis or dermis component shrinkage. The method and apparatus also may be employed in the treatment of capillary malformation (port wine stain).