The cause is usually pressure from the flange of a denture which causes chronic irritation and a hyperplastic response in the soft tissues. Women during pregnancy can also present with an epulis, which will resolve after birth. Fibroepithelial polyps, pedunculated lesions of the palate beneath an upper denture, are associated with this condition. A cobble-stone appearance similar to an epulis fissuratum in a patient without dentures can be diagnostic of Crohn's disease. Epulis fissuratum can also appear around dental implants.

The terms gingival hyperplasia and gingival hypertrophy have been used to describe this topic in the past. These are not precise descriptions of gingival enlargement because these terms are strictly histologic diagnoses, and such diagnoses require microscopic analysis of a tissue sample. Hyperplasia refers to an increased number of cells, and hypertrophy refers to an increase in the size of individual cells. As these identifications obviously cannot be performed with a clinical examination and evaluation of the tissue, the term "gingival enlargement" is more properly applied. Gingival enlargement has been classified according to cause into 5 general groups:

- Inflammatory enlargement

- Drug induced enlargement

- Enlargement associated with systemic diseases or conditions

- Neoplastic enlargement

- False enlargement.

The lesion is usually painless. The usual appearance is of two excess tissue folds in alveolar vestibule/buccal sulcus, with the flange of the denture fitting in between the two folds. It may occur in either the maxillary or mandibular sulci, although the latter is more usual. Anterior locations are more common than posterior. Less commonly there may be a single fold, and the lesion may appear on the lingual surface of the mandibular alveolar ridge.

The swelling is firm and fibrous, with a smooth, pink surface. The surface may also show ulceration or erythema. The size of the lesion varies from less than 1 cm to involving the entire length of the sulcus.

Gingival enlargement, (also termed gingival overgrowth, hypertrophic gingivitis, gingival hyperplasia, or gingival hypertrophy, and sometimes abbreviated to GO), is an increase in the size of the gingiva (gums). It is a common feature of gingival disease. Gingival enlargement can be caused by a number of factors, including inflammatory conditions and the side effects of certain medications. The treatment is based on the cause. A closely related term is epulis, denoting a localized tumor (i.e. lump) on the gingiva.

Gingival and periodontal pockets are dental terms indicating the presence of an abnormal depth of the gingival sulcus near the point at which the gingival tissue contacts the tooth.

On the shaft of the penis, Fordyce spots are more visible when the skin is stretched, and may only be noticeable during an erection.

The spots can also appear on the skin of the scrotum.

Oral Fordyce granules appear as rice-like granules, white or yellow-white in color. They are painless papules (small bumps), about 1–3 mm in greatest dimension. The most common site is along the line between the vermilion border and the oral mucosa of the upper lip, or on the buccal mucosa (inside the cheeks) in the commissural region, often bilaterally. They may also occur on the mandibular retromolar pad and tonsillar areas, but any oral surface may be involved. There is no surrounding mucosal change. Some patients will have hundreds of granules while most have only one or two.

Occasionally, several adjacent glands will coalesce into a larger cauliflower-like cluster similar to sebaceous hyperplasia of the skin. In such an instance, it may be difficult to determine whether or not to diagnose the lesion as sebaceous hyperplasia or sebaceous adenoma. The distinction may be moot because both entities have the same treatment, although the adenoma has a greater growth potential. Sebaceous carcinoma of the oral cavity has been reported, presumably arising from Fordyce granules or hyperplastic foci of sebaceous glands.

In some persons with Fordyce spots, the glands express a thick, chalky discharge when squeezed.

Heck's disease (also known as focal or multifocal epithelial hyperplasia) is an asymptomatic, benign neoplastic condition characterized by multiple white to pinkish papules that occur diffusely in the oral cavity. Can present with slightly pale, smooth or roughened surface morphology. It is caused by the human papilloma virus types 13 and 32. It exhibits surface cells with vacuolated cytoplasm around irregular, pyknotic nuclei and occasional cells with mitosis-like changes within otherwise mature and well-differentiated epithelium. A distinguishing histologic feature is elongated rete ridges resembling Bronze Age axe with mitosoid bodies present. It was first identified in the Aboriginal population.

Over time, they will spontaneously regress without treatment. Possible treatment may be excisional biopsy for lesions of functional or aesthetic concern.

Normally, sebaceous glands are only found in association with a hair follicle.

They appear to be more obvious in people with oily skin types, with some rheumatic disorders, and in hereditary nonpolyposis colorectal cancer. In the latter, the most common site for Fordyce spots is the lower gingiva (gums) and vestibular mucosa.

Sebaceous hyperplasia is a disorder of the sebaceous glands in which they become enlarged, producing flesh-colored or yellowish, shiny, often umbilicated bumps on the face. Newly formed nodules often swell with sweating (which is pathognomonic for the condition), but this diminishes over time.

Sebaceous glands are glands located within the skin and are responsible for secreting an oily substance named sebum. They are commonly associated with hair follicles but they can be found in hairless regions of the skin as well. Their secretion lubricates the skin, protecting it from drying out or becoming irritated.

Sebaceous hyperplasia generally affects newborns as well as middle-aged to elderly adults. The symptoms of this condition are 1–5 mm papules on the skin, mainly on the forehead, nose and cheeks, and seborrheic facial skin. The papules may be cauliflower-shaped. In infants, acne is sometimes associated with sebaceous hyperplasia.

Drug-related gingival hyperplasia is a cutaneous condition characterized by enlargement of the gums noted during the first year of drug treatment. There are three drug classes that are associated with this condition namely, anticonvulsants (such as phenyotoin and phenobartibal), calcium channel blocker (such as amlopidine, nifedipine and verapamil) and ciclosporin, an immunosuppressant Although the mechanism of drug related gingival hyperplasia is not well understood, some risk factors for the condition include the duration of drug use and poor oral hygiene. In most cases, alternative drugs are given, in order to avoid this side effect.

As the original sulcular depth increases and the apical migration of the junctional epithelium has simultaneously occurred, the pocket is now lined by pocket epithelium (PE) instead of junctional epithelium (JE). To have a true periodontal pocket, a probing measurement of 4 mm or more must be clinically evidenced. In this state, much of the gingival fibers that initially attached the gingival tissue to the tooth have been irreversibly destroyed. The depth of the periodontal pockets must be recorded in the patient record for proper monitoring of periodontal disease. Unlike in clinically healthy situations, parts of the sulcular epithelium can sometimes be seen in periodontally involved gingival tissue if air is blown into the periodontal pocket, exposing the newly denuded roots of the tooth. A periodontal pocket can become an infected space and may result in an abscess formation with a papule on the gingival surface. Incision and drainage of the abscess may be necessary, as well as systemic antibiotics; placement of local antimicrobial delivery systems within the periodontal pocket to reduce localized infections may also be considered.

It is classified as supra bony and infra bony based on its depth in relation to alveolar bone.

Cutaneous lymphoid hyperplasia refers to a groups of benign cutaneous disorders characterized by collections of lymphocytes, macrophages, and dendritic cells in the skin. Conditions included in this groups are:

- Cutaneous lymphoid hyperplasia with nodular pattern, a condition of the skin characterized by a solitary or localized cluster of asymptomatic erythematous to violaceous papules or nodules

- Cutaneous lymphoid hyperplasia with bandlike and perivascular patterns, a condition of the skin characterized by skin lesions that clinically resemble mycosis fungoides

NME features a characteristic skin eruption of red patches with irregular borders, intact and ruptured vesicles, and crust formation. It commonly affects the limbs and skin surrounding the lips, although less commonly the abdomen, perineum, thighs, buttocks, and groin may be affected. Frequently these areas may be left dry or fissured as a result. All stages of lesion development may be observed synchronously. The initial eruption may be exacerbated by pressure or trauma to the affected areas.

The histopathologic features of NME are nonspecific and include:

- epidermal necrosis

- subcorneal pustules

- confluent parakeratosis, epidermal hyperplasia, and marked papillary dermal hyperplasia in a psoriasiform pattern

- angioplasia of papillary dermis

- suppurative folliculitis

The vacuolated, pale, swollen epidermal cells and necrosis of the superficial epidermis are most characteristic. Immunofluorescence is usually negative.

Secretan’s syndrome is a rare condition of hard edema and traumatic hyperplasia of the dorsum of the hand. Most expert view it as a self-inflicted condition.

It was first described in 1901 by Henri-François Secretan, a Swiss insurance physician. He described a condition characterized by a hard, sometimes cyanotic edema (Charcot's blue edema) on the dorsal aspect of the hand.

This condition which some people think is a self-inflicted (factitious) condition usually starts with a small accidental injury of the dorsum of the hand. This is usually followed by swelling edema and cyanosis of the dorsum of the usually right hand.

The edema is thought to be secondary to excessive inflammation the condition slowly burns out with the edema being replaced by fibrosis surrounding the extensor tendons of the hand.

Although a clear understanding of the various skin lesions in IgG4-related disease is a work in progress, skin lesions have been classified into subtypes based on documented cases:

- Angiolymphoid hyperplasia with eosinophilia (or lesions that mimic it) and cutaneous pseudolymphoma

- Cutaneous plasmacytosis

- Eyelid swelling (as part of Mikulicz's disease)

- Psoriasis-like eruptions

- Unspecified maculopapular or erythematous eruptions

- Hypergammaglobulinemic purpura and urticarial vasculitis

- Impaired blood supply to fingers or toes, leading to Raynaud's phenomenon or gangrene

Note:

In addition, Wells syndrome has also been reported in a case of IgG4-related disease.

Jessner lymphocytic infiltrate of the skin is a cutaneous condition characterized by a persistent papular and plaque-like skin eruption which can occur on the neck, face and back and may re-occur. This is an uncommon skin disease and is a benign collection of lymph cells. Its cause is not known and can be hereditary. It is named for Max Jessner. It is thought to be equivalent to lupus erythematosus tumidus.

It can occur as the result of ACE inhibitors and a number of medications used to treat multiple sclerosis including glatiramer acetate.

Angiolymphoid hyperplasia with eosinophilia (also known as: "Epithelioid hemangioma," "Histiocytoid hemangioma," "Inflammatory angiomatous nodule," "Intravenous atypical vascular proliferation," "Papular angioplasia," "Inflammatory arteriovenous hemangioma," and "Pseudopyogenic granuloma") usually presents with pink to red-brown, dome-shaped, dermal papules or nodules of the head or neck, especially about the ears and on the scalp.

It, or a similar lesion, has been suggested as a feature of IgG4-related skin disease, which is the name used for skin manifestations of IgG4-related disease.

Pacman dysplasia (alternatively known as epiphyseal stippling with osteoclastic hyperplasia) is a lethal autosomal recessive skeletal dysplasia. The dysplasia is present during fetal development.

Blepharophyma is chronic swelling of eyelids, mainly due to sebaceous gland hyperplasia.

Follicular hyperplasia (or "reactive follicular hyperplasia" or "lymphoid nodular hyperplasia") is a type of lymphoid hyperplasia. It is caused by a stimulation of the B cell compartment. It is caused by an abnormal proliferation of secondary follicles and occurs principally in the cortex without broaching the lymph node capsule. The follicles are cytologically polymorphous, are often polarized, and vary in size and shape. Follicular hyperplasia is distinguished from follicular lymphoma in its polyclonality and lack of bcl-2 protein expression, whereas follicular lymphoma is monoclonal, and does express bcl-2).

Papillomatosis is skin surface elevation caused by hyperplasia and enlargement of contiguous dermal papillae. These papillary projections of the epidermis form an undulating surface under microscopic examination.

Some specific reactive lymphadenopathies with a predominantly follicular pattern:

- Rheumatoid arthritis

- Sjogren syndrome

- IgG4-related disease (IgG4-related lymphadenopathy)

- Kimura disease

- Toxoplasmosis

- Syphilis

- Castleman disease

- HIV-associated lymphadenopathy

- Progressive transformation of germinal centers (PTGC)

Lymphoid hyperplasia is the rapid growth proliferation of normal cells that resemble lymph tissue.

IgG4-related skin disease is the recommended name for skin manifestations in IgG4-related disease (IgG4-RD). Multiple different skin manifestations have been described.