Secondary closure involves allowing a wound to heal by granulation, contraction, and epithelialization without surgical closure. This process typically results in greater scar tissue formation due to prolonged inflammation and wound contraction. In contrast, primary closure and delayed primary closure approximate wound edges earlier, minimizing tension and scar width. Subcuticular closure provides a cosmetic closure technique but does not inherently influence scar width more than the timing of closure. Therefore, wounds healed by secondary intention generally produce wider and more noticeable scars.

Reference: Sabiston Textbook of Surgery, 21st Edition.