Acatalasia (acatalasemia, Takaharas disease)
Acquired dyskeratotic leukoplakia
Actinic cheilitis (actinic cheilosis)
Acute necrotizing ulcerative gingivitis (acute membranous gingivitis, acute necrotizing ulcerative gingivostomatitis, fusospirillary gingivitis, fusospirillosis, fusospirochetal gingivitis, necrotizing gingivitis, phagedenic gingivitis, trench mouth, ulcerative gingivitis, Vincent gingivitis, Vincent infection, Vincent stomatitis, Vincents disease)
Allergic contact cheilitis
Angina bullosa haemorrhagica
Angular cheilitis (perlèche)
Behçets disease (Behçets syndrome, oculo-oral-genital syndrome)
Black hairy tongue (hairy tongue, lingua villosa nigra) 
Caviar tongue
Cheilitis exfoliativa
Cheilitis glandularis
Cheilitis granulomatosa (granulomatous cheilitis, orofacial granulomatosis)
Cutaneous sinus of dental origin (dental sinus)
Cyclic neutropenia
Desquamative gingivitis
Drug-induced ulcer of the lip
Epidermization of the lip
Epulis
Epulis fissuratum (granuloma fissuratum)
Eruptive lingual papillitis
Erythroplakia (erythroplasia)
Fissured tongue (furrowed tongue, lingua plicata, plicated tongue, scrotal tongue)
Geographic tongue (benign migratory glossitis, benign migratory stomatitis, glossitis areata exfoliativa, glossitis areata migrans, lingua geographica, stomatitis areata migrans, transitory benign plaques of the tongue)
Gingival fibroma
Gingival hypertrophy
Hairy leukoplakia (oral hairy leukoplakia)
Intraoral dental sinus
Linea alba
Leukoplakia
Leukoplakia with tylosis and esophageal carcinoma
Major aphthous ulcer (periadenitis mucosa necrotica recurrens)
Median rhomboid glossitis (central papillary atrophy)
Melanocytic oral lesion
Melkersson–Rosenthal syndrome
Morsicatio buccarum (chronic cheek biting, chronic cheek chewing)
Mucosal squamous cell carcinoma
Mucous cyst of the oral mucosa (mucocele)
Nagayamas spots
Oral Crohns disease
Oral florid papillomatosis
Oral melanosis
Osseous choristoma of the tongue
Peripheral ameloblastoma
Plasma cell cheilitis (plasma cell gingivitis, plasma cell orificial mucositi)
Plasmoacanthoma
Proliferative verrucous leukoplakia
Pyogenic granuloma (eruptive hemangioma, granulation tissue-type hemangioma, granuloma gravidarum, lobular capillary hemangioma, pregnancy tumor, tumor of pregnancy)  
Pyostomatitis vegetans
Recurrent aphthous stomatitis (aphthosis, canker sores, recurrent oral aphthae)
Recurrent intraoral herpes simplex infection
Smooth tongue (atrophic glossitis, bald tongue, hunter glossitis, moeller)
Stomatitis nicotina (nicotine stomatitis, smokers keratosis, smokers patches)
Torus palatinus
Trumpeters wart
Vestibular papillomatosis
White sponge nevus (white sponge nevus of Cannon)

Conditions of the skin appendages
Conditions of the skin appendages are those affecting the glands of the skin, hair, nails, and arrector pili muscles.
Annular lichen planus 
Atrophic lichen planus
Bullous lichen planus (vesiculobullous lichen planus)
Erosive lichen planus
Erythema dyschromicum perstans (ashy dermatosis, dermatosis cinecienta)
Giant cell lichenoid dermatitis
Hepatitis-associated lichen planus
Hypertrophic lichen planus (lichen planus verrucosus)
Idiopathic eruptive macular pigmentation
Inverse lichen planus
Keratosis lichenoides chronica (Nékams disease)
Kraurosis vulvae
Lichen nitidus
Lichen planus actinicus (actinic lichen niditus, actinic lichen planus, lichen planus atrophicus annularis, lichen planus subtropicus, lichen planus tropicus, lichenoid melanodermatitis, lichenoid melanodermatosis, summertime actinic lichenoid eruption)
Lichen planus pemphigoides
Lichen planus pigmentosus
Lichen planus–lichen sclerosus overlap syndrome
Lichen ruber moniliformis
Lichen sclerosus (lichen sclerosus et atrophicus)
Lichen striatus (Blaschko linear acquired inflammatory skin eruption, linear lichenoid dermatosis)
Lichen verrucosus et reticularis
Lichenoid trikeratosis
Lichenoid dermatitis
Lichenoid reaction of graft-versus-host disease
Linear lichen planus
Mucosal lichen planus
Peno-gingival syndrome
Ulcerative lichen planus
Vulvovaginal gingival syndrome
Vulvovaginal lichen planus

Lymphoid-related
Lymphoid-related cutaneous conditions are a group of disorders characterized by collections of lymphocyte cells within the skin.