| Phenotype (plain language) | Suggested HPO term(s) | Onset/progression notes | Evidence details (include any numeric thresholds/recurrence) | Key citation IDs |
|---|---|---|---|---|
| Gingival fibromatosis / gingival enlargement | HP: Gingival overgrowth; HP: Gingival fibromatosis | Usually begins with eruption of primary or permanent teeth; slow, progressive; rarely present at birth | Benign, fibrous, non-hemorrhagic enlargement affecting marginal/attached gingiva and interdental papillae; may cover part or all of tooth crowns; one clinical threshold used in a linkage study was enlargement covering at least one-third of the clinical crowns of 5 or more teeth | (pqac-00000017, pqac-00000018, pqac-00000019, pqac-00000023) |
| Non-hemorrhagic, firm, fibrotic gingiva | HP: Abnormality of gingiva; HP: Gingival overgrowth | Chronic/insidious; typically stable-to-progressive rather than episodic | Gingiva described as pale pink, firm, leathery/dense, fibrotic, often nodular, and not bleeding easily; in severe cases may feel hard on palpation | (pqac-00000016, pqac-00000021, pqac-00000035) |
| Generalized versus localized/nodular overgrowth | HP: Gingival overgrowth | Variable extent; can be diffuse in both jaws, part-diffuse in one jaw, or localized nodular | Reported phenotypes range from localized nodules to generalized enlargement of maxilla and mandible; upper gingiva may predominate in some reports | (pqac-00000018, pqac-00000019, pqac-00000022) |
| Broad/excess keratinized gingiva | HP: Abnormality of gingiva | Often evident in childhood/primary dentition period | Review describes an “extremely wide zone of keratinized gingiva” early in the course; lesions confined to masticatory mucosa and typically do not extend beyond the mucogingival junction | (pqac-00000018) |
| Pseudopocket formation | HP: Abnormality of gingiva | Develops as tissue enlarges and covers crowns | Excess tissue can create pseudopockets; these predispose to plaque retention, bleeding, and periodontal complications | (pqac-00000016, pqac-00000017, pqac-00000022) |
| Plaque accumulation / impaired oral hygiene | HP: Abnormality of the periodontium | Secondary consequence of progressive tissue excess | Pseudopockets create niches for microorganisms and plaque accumulation; daily oral hygiene becomes difficult in severe disease | (pqac-00000016, pqac-00000019, pqac-00000023) |
| Periodontal complications | HP: Periodontitis; HP: Abnormality of the periodontium | Secondary/downstream manifestation; worsens with poor hygiene and plaque retention | Reported complications include bleeding, periodontal problems, bone loss, and risk of progressive periodontal disease if untreated | (pqac-00000017, pqac-00000021, pqac-00000023) |
| Delayed tooth eruption / retained teeth / impaction | HP: Delayed eruption of teeth; HP: Retained primary teeth; HP: Impacted teeth | Often recognized around tooth eruption; may obstruct eruption of permanent teeth | Reported findings include retention of primary or permanent teeth, delayed eruption, impacted teeth, and permanent teeth lying beneath gingival tissue on radiographs | (pqac-00000017, pqac-00000018, pqac-00000021, pqac-00000022) |
| Diastema / spaced teeth | HP: Diastema | May emerge with progression as tissue excess displaces teeth | Diastemas and spaced teeth are repeatedly described, especially in more severe generalized disease | (pqac-00000017, pqac-00000018, pqac-00000020) |
| Malocclusion / tooth displacement / malposition | HP: Malocclusion; HP: Dental malposition | Progressive; often becomes evident during mixed/permanent dentition | Tooth displacement, malposition, crossbite/open bite, and facial asymmetry may occur due to overgrowth and eruption disturbance | (pqac-00000016, pqac-00000018, pqac-00000022) |
| Speech difficulty | HP: Dysarthria; HP: Abnormal speech articulation | More common in moderate-severe generalized disease | Review and case-series evidence describe phonetic/articulation difficulties caused by bulky gingiva and altered occlusion | (pqac-00000018, pqac-00000021, pqac-00000035) |
| Mastication/chewing difficulty | HP: Abnormality of chewing; HP: Feeding difficulties | More prominent when crowns are largely covered or teeth eruption is impaired | Patients can have chewing difficulty, impaired occlusion, and functional limitations; surgery often improves masticatory function | (pqac-00000016, pqac-00000018, pqac-00000022, pqac-00000034) |
| Psychosocial / aesthetic impact | HP: Psychological distress | Chronic impact that increases with visible overgrowth during childhood/adolescence | Aesthetic concerns, psychosocial effects, and reduced quality of life are commonly described, especially in younger patients | (pqac-00000017, pqac-00000018, pqac-00000021, pqac-00000039) |
| Histopathology: dense collagenized stroma | HP: Abnormal oral mucosa morphology | Structural hallmark rather than temporal feature | Histology shows markedly increased submucosal connective tissue, densely collagenized/cell-poor stroma, excessive ECM/collagen bundles, and relatively few blood vessels | (pqac-00000016, pqac-00000020, pqac-00000023, pqac-00000037) |
| Histopathology: elongated rete pegs / epithelial hyperplasia | HP: Abnormality of oral epithelium | Persistent microscopic feature | Epithelium is hyperkeratotic/hyperplastic with elongated rete ridges/pegs; pseudoepitheliomatous hyperplasia may occur in severe cases | (pqac-00000019, pqac-00000023, pqac-00000032, pqac-00000037) |
| Histopathology: scant inflammation | HP: Abnormal inflammatory response | Usually minimal unless secondary plaque-related inflammation develops | Classic HGF tissue has scant or minimal inflammatory infiltrate; inflammation increases secondarily with plaque retention and pseudopockets | (pqac-00000016, pqac-00000023, pqac-00000032) |
| Recurrence after surgery | HP: Recurrent oral soft tissue lesion | Recurrence risk persists long term; higher in children/adolescents | Reported recurrence commonly occurs within 3-10 years after surgery; one 2024 surgical review cites recurrence around 35%; recurrence at 1 year has also been documented, and performing surgery after eruption of permanent teeth may reduce recurrence | (pqac-00000016, pqac-00000020, pqac-00000033, pqac-00000039) |


*Table: This table summarizes the core clinical phenotype, diagnostic features, and histopathology of hereditary gingival fibromatosis, with suggested HPO mappings and practical notes on onset, progression, and recurrence. It is useful for structured disease knowledge-base curation and phenotype annotation.*