a, The palatal vault is covered by small fibrous papules representing inflammatory papillary hyperplasia. b, Low-power view showing fibrous and epithelial hyperplasia resulting in papillary surface projections. A chronic inflammatory infiltrate is present in the superficial connective tissue and extends into the epithelium. Periodic acid Schiff staining revealed the presence of fungal hyphae in the keratin layer, compatible with Candida spp. (original magnification × 25, Hematoxylin & eosin). (from Non-HPV Papillary Lesions of the Oral Mucosa: Clinical and Histopathologic Features of Reactive and Neoplastic Conditions)
IPH is a reactive tissue overgrowth that typically develops on the denture-bearing hard palate. Factors implicated in the etiopathology include candidiasis, poor oral hygiene, an ill-fitting or old denture, smoking, old age, continuous and nighttime wear of a denture. IPH has been considered part of the spectrum of denture stomatitis (Newton’s classification type III). Clinically, the hard palate mucosa appears hyperemic and covered in small, painless, nodular or papillary growths. These changes usually begin on the palatal vault but can extend to involve the entire hard palate. The degree of inflammation is variable. IPF can also be seen in dentate patients with a deep palatal vault or who breathe with their mouths. IPH is usually asymptomatic and most patients are unaware of its presence.
The diagnosis of IPH is based on the clinical appearance of the mucosa. A biopsy is rarely indicated. When tissue is submitted, papillary projections are seen, surfaced by nonkeratotic or parakeratotic stratified squamous epithelium. The epithelium alternates between areas of atrophy and acanthosis extending deep within the lamina propria. Pseudoepitheliomatous hyperplasia can be present, which should not be mistaken for a well-differentiated OSCC. The lamina propria can be edematous or fibrotic, and supports a lymphoplasmacytic infiltrate. Candidal hyphae are seldom identified, since they are mostly located on the tissue-bearing surface of the denture.
Management of IPH consists of providing patient education regarding denture wear and hygiene, improving denture fit, fabricating new dentures, and treating fungal infection. Once the sources of inflammation have been removed, the erythema and edema resolve, but the papillary appearance of the mucosa may not completely disappear. In cases where persisting fibrous tissue obstructs the proper fitting of a maxillary denture, the excess tissue can be surgically removed. In most situations, however, IPH requires no further treatment once the inflammation has reduced.