Early and Late Effects of Hyaluronic Acid and Calcium Hydroxylapatite Dermal Fillers on Labial Mucosa of Old Female Albino Rats (Histological and Ultrastructural Study)

Abstract

Aging face is marked by loss of fat and soft tissue volume with loss of skin collagen and elasticity. Diminished support from underlying muscle and bone results in observable and sometimes profound changes. These changes include skin fragility and increased wrinkles. Surgical and/or injection techniques could be used to enhance the aging face changes. Sub-epidermal injections of dermal fillers are used for lipoatrophy correction and soft tissue augmentation of different parts of the body. Recently, the face is injected with dermal fillers to reduce facial lines and pits such as perioral rhytides. Moreover, fillers are used to smoothen out wrinkles, restore volume and enhance soft tissue such as cheek and lips. Fillers are also used for correction of atrophic scars and small cutaneous defects. Fillers could be used solely or combined. Fillers can be classified depending on the length of time the substance remains in tissue; as temporary, semipermanent or permanent. Moreover, adverse reactions were reported such as pain, needle marks, itching, bruising, erythema and oedema. Ulceration, scarring, migration of the injected filler, development of inflammatory nodules and foreign body granulomas also have been reported. Most adverse reactions occur immediately after injection and last from hours to a few days.