Search

Decreased or increased activity of potassium channels caused by loss-of-function and gain-of-function (GOF) variants in the corresponding genes, respectively, underlies a broad spectrum of human disorders affecting the central nervous system, heart, kidney, and other organs. While the association of epilepsy and intellectual disability (ID) with variants affecting function in genes encoding potassium channels is well known, GOF missense variants in K+ channel encoding genes in individuals with syndromic developmental disorders have only recently been recognized. These syndromic phenotypes include Zimmermann–Laband and Temple–Baraitser syndromes, caused by dominant variants in KCNH1, FHEIG syndrome due to dominant variants in KCNK4, and the clinical picture associated with dominant variants in KCNN3. Here we review the presentation of these individuals, including five newly reported with variants in KCNH1 and three additional individuals with KCNN3 variants, all variants likely affecting function. There is notable overlap in the phenotypic findings of these syndromes associated with dominant KCNN3, KCNH1, and KCNK4 variants, sharing developmental delay and/or ID, coarse facial features, gingival enlargement, distal digital hypoplasia, and hypertrichosis. We suggest to combine the phenotypes and define a new subgroup of potassium channelopathies caused by increased K+ conductance, referred to as syndromic neurodevelopmental K+ channelopathies due to dominant variants in KCNH1, KCNK4, or KCNN3.

Background and objective Activated potassium channels were found to be strongly correlated with gingival overgrowth (GO) phenotype as we reviewed syndromic hereditary gingival fibromatosis (HGF). Nevertheless, the functional roles of potassium channels in gingival fibrosis or gingival overgrowth remained uncovered. The aim of the present study was to explore the pathogenic role of aberrantly activated potassium channel in Hereditary Gingival Fibromatosis (HGF). Methods Gingival tissues were collected from 9 HGF patients and 15 normal controls. Expression of KCNQ1 was detected by immunohistochemistry. Gingival fibroblasts were isolated, and outward K+ currents were detected by whole-cell patch-clamp analysis, transmembrane potential was determined by flow cytometry. Normal human gingival fibroblasts (NHGFs) were transfected with KCNQ1 adenovirus or treated with KCNQ1 selective agonist ML277 and antagonist chromanol 293B. Accumulation of Extracellular Matrix (ECM) was measured by Western blotting and Sircol Soluble Collagen Assay. Content of secreted TGF-β1 was measured by ELISA. Active RAS pull-down assay and cell immunofluorescence were utilized to verify RAS activation. Results KCNQ1 was upregulated in gingival tissues derived from HGF patients and HGF gingival fibroblasts presented increased outward K+ currents than NHGFs. Overexpression of KCNQ1, or KCNQ1 agonist ML277, promoted fibrotic responses of NHGFs. TGF-β1 and KCNQ1 channels formed a positive feed-back loop. ML277 generated lateral clustering and activation of Ras on plasma membrane, followed by augmented MAPK/AP-1 signaling pathway output. JNK or ERK1/2 inhibitors suppressed ML277-induced AP-1 and ECM upregulation. Conclusion Activation of KCNQ1 potassium channel promoted fibrogenic responses in NHGFs via Ras/MAPK/AP-1 signaling.

Hereditary gingival fibromatosis (HGF) is an uncommon, inherited condition with slow and progressive fibrous hyperplasia of the gingiva. Due to its association with mastication, speech, and occlusion problems, early diagnosis is important. We sought to summarize the available data regarding the epidemiology, clinical characteristics, and outcomes of children with HGF (< 18 years). A systematic literature review of the MEDLINE and Cochrane Library databases was conducted with respect to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (end-of-search date: March 1, 2019). A total of 99 articles reporting on 146 patients were included. The mean age was 10.82 ± 3.93 years, and generalized gingival enlargement was seen in 97.16% (95% CI 92.69 to 99.14). Jaw, gingival, and teeth abnormalities; poor oral hygiene; eating; or speech difficulties were typical HGF-induced, while 60.90% had extraoral manifestations (95% CI 52.41 to 68.78). The disease was most commonly inherited in an autosomal dominant manner (88.41%, 95% CI 78.5 to 94.26), and about one-third of the patients had syndromic HGF (33.85%, 95% CI 23.50 to 46.00). Gingivectomy was performed in the majority of cases (91.15%, 95% CI 84.31 to 95.29), and recurrence was seen in 33.85% (95% CI 23.50 to 46.00). HGF should be suspected in children with nodularity and gingival fibrosis, teeth abnormalities, or jaw distortion. Family history can help to establish the diagnosis. More cases should focus on longer-term follow-up after gingivectomy as disease recurrence is not uncommon.

Objective The aim of systematic review was to describe the phenotypes and molecular profiles of syndromes with gingival fibromatosis (GF). Methods A comprehensive search of PubMed, LILACS, Livivo, Scopus, and Web of Science was conducted using key terms relevant to the research questions and supplemented by a gray literature search. The Methodological Quality and Synthesis of Case Series and Case Reports in association with the Case Series and Prevalence Studies from the Joanna Briggs Institute critical appraisal tools were used for the risk of bias. We followed the PRISMA checklist guidelines. Results Eighty-four studies reporting GF as an oral manifestation of a syndrome were identified in this review. Enamel renal syndrome was the most frequently reported syndrome with GF, represented by 54 individuals in 19 studies, followed by Zimmermann-Laband syndrome with 24 individuals in 15 studies and Costello syndrome, which was presented in a case series study with 41 individuals. Among reported cases, other clinical manifestations such as hypertrichosis, ectopic gingival calcification, and cherubism were described. Conclusions The results emphasize the need of systematic oro-dental-facial phenotyping for future descriptions as well as further molecular analysis in order to better understand the occurrence of syndromic GF.

Our aim is to describe a family with a nonsyndromic form of hereditary gingival fibromatosis (HGF) and discuss genetic characteristics of this rare disease by reviewing reported cases. A mother and three descendants were diagnosed with HGF. There was marked variable expressivity: from severe generalized gingival overgrowth in a 16-year-old boy (the proband) to minimal manifestations in the mother. The proband was submitted to gingivectomy and gingivoplasty. In younger siblings, the disease remained stable for 5 years, suggesting that clinical surveillance is a good option. The diagnosis was supported by histopathological examination. Analysis of this family and literature-reported cases supports that HGF most frequently shows an autosomal dominant inheritance with high penetrance and variable expressivity. Neomutations and gonadal mosaicism do not seem to be a rare event. Although five loci have been mapped by linkage analysis, only two genes, SOS1 and REST, were identified in four families.

Background Hereditary gingival fibromatosis (HGF) is a rare condition characterized by slowly progressive overgrowth of the gingiva. The severity of overgrowth may differ from mild causing phonetic and masticatory issues, to severe resulting in diastemas or malposition of teeth. Both, autosomal-dominant and autosomal-recessive forms of HGF are described. The aim of this review is a clinical overview, as well as a summary and discussion of the involvement of candidate chromosomal regions, pathogenic variants of genes, and candidate genes in the pathogenesis of HGF. The loci related to non-syndromic HGF have been identified on chromosome 2 (GINGF, GINGF3), chromosome 5 (GINGF2), chromosome 11 (GINGF4), and 4 (GINGF5). Of these loci, pathogenic variants of the SOS-1 and REST genes inducing HGF have been identified in the GINGF and the GINGF5, respectively. Furthermore, among the top 10 clusters of genes ranked by enrichment score, ATP binding, and fibronectin encoding genes were proposed as related to HGF. Conclusion The analysis of clinical reports as well as translational genetic studies published since the late’90s indicate the clinical and genetic heterogeneity of non-syndromic HGF and point out the importance of genetic studies and bioinformatics of more numerous unrelated families to identify novel pathogenic variants potentially inducing HGF. This strategy will help to unravel the molecular mechanisms as well as uncover specific targets for novel and less invasive therapies of this rare, orphan condition.

Background Hyaline fibromatosis syndrome (HFS) is a rare autosomal recessive disorder caused by mutations in the gene for anthrax toxin receptor-2 (ANTXR2). The clinical features of HFS include skin thickening with nodules, papules and plaques, gingival enlargement, joint stiffness and contractures, and systemic manifestations. Notably, in all patients with HFS reported in the literature, gingival enlargement has never occurred alone. Case presentation A case of a child with gingival enlargement as the only clinical manifestation, who was later diagnosed with HFS, is described. In this case, the absence of skin and joint lesions and other characteristic clinical presentations gave rise to a diagnostic problem. This uncommon condition was clinically indistinguishable from other diseases or conditions that presented with diffuse gingival enlargement. A definitive diagnosis of HFS was reached through genetic analysis. Trio whole exome sequencing revealed compound heterozygous mutations of ANTXR2 in this patient and two new mutations were reported. Conclusions The findings of this case serve as an important reminder to clinicians. When dental practitioners encounter gingival manifestations of HFS without accompanied skin or joint involvement, there is a need to pay attention to the differential diagnosis and increase awareness of HFS.

Background Hereditary gingival fibromatosis (HGF) is rare in clinical practice, and the long-term results of the combined orthodontic-periodontal treatment of HGF are rarely reported. Case presentation This study reports for the first time the results of seven years of follow-up in a seven-year-old girl with HGF. The diagnosis was confirmed by clinical signs, family history and histopathological examination. First, periodontal scaling and oral hygiene reinforcement were performed regularly in the mixed dentition stage. Next, gingivoplasty was performed on the permanent dentition. Two months after the surgery, treatment with fixed orthodontic appliances was conducted. The teeth were polished on a monthly basis, and oral hygiene was reinforced to control gingival enlargement. Gingival hypertrophy recurred slightly, and gingivectomies were performed in the months following the start of orthodontic treatment. Follow-up was performed for 24 months with orthodontic retention, and gingival enlargement remained stable after the combined treatment. Conclusions The risk of gingival hyperplasia recurrence during and after orthodontic treatment is high, but satisfying long-term outcomes can be achieved with gingivectomy, malocclusion correction, and regular follow-up maintenance.

Idiopathic gingival fibromatosis (IGF) is a rare, genetically heterogeneous condition that is usually a part of syndrome or, rarely, an isolated disorder. It is characterized by a slowly progressive, non hemorrhagic, fibrous enlargement of keratinized gingiva which usually begins at the time of eruption of permanent dentition, however very few cases involving the primary teeth have been described in literature. Congenital gingival fibromatosis is very rare condition in which the gingival tissues become thickened and erupting teeth remain submerged beneath hyperplastic tissue masses. This case report discusses the rare case of congenital non syndromic idiopathic gingival fibromatosis in a two year old boy who reported with absence of teeth and incompetent lips. Gingivectomy was done using modified microdissection electrocautery needle to remove the excess gingival tissues. Excised tissue has been examined histologically. The patient was followed up for a period of one year and no recurrence was observed.

Hereditary gingival fibromatosis (HGF) is a rare genetic condition characterized by slow and progressive gingival enlargement. The gingival overgrowth often delays teeth eruption and may cause serious functional and aesthetic problems. We reported a case of a 10-year-old female child presenting a generalized gingival enlargement covering almost all the maxillary and mandibular teeth and resulted in problems for swallowing, speaking, and poor aesthetics. An incisional biopsy was performed and revealed a hypocellular and hypovascular dense collagenous tissue covered by squamous epithelium exhibiting acanthosis and elongated rete ridges. The diagnosis was HGF. The treatment instituted was an association of gingivectomy with a rigorous program of oral hygiene and follow-up. Herein, we describe a rare non-syndromic case of generalized HGF, including clinical and microscopical features, as well as highlighting the importance of correct diagnosis of this genetic condition.

Cantú syndrome (CS) is a rare developmental disorder characterized by a coarse facial appearance, macrocephaly, hypertrichosis, skeletal and cardiovascular anomalies and caused by heterozygous gain-of-function variants in ABCC9 and KCNJ8, encoding subunits of heterooctameric ATP-sensitive potassium (KATP) channels. CS shows considerable clinical overlap with Zimmermann- Laband syndrome (ZLS), a rare condition with coarse facial features, hypertrichosis, gingival overgrowth, intellectual disability of variable degree, and hypoplasia or aplasia of terminal phalanges and/or nails. ZLS is caused by heterozygous gain-of-function variants in KCNH1 or KCNN3, and gain-of-function KCNK4 variants underlie the clinically similar FHEIG (facial dysmorphism, hypertrichosis, epilepsy, intellectual disability/developmental delay, and gingival overgrowth) syndrome ; KCNH1, KCNN3 and KCNK4 encode potassium channels. Within our research project on ZLS, we performed targeted Sanger sequencing of ABCC9 in 15 individuals tested negative for a mutation in the ZLS- associated genes and found two individuals harboring a heterozygous pathogenic ABCC9 missense variant. Through a collaborative effort, we identified a total of nine individuals carrying a monoallelic ABCC9 variant: five sporadic patients and four members of two unrelated families. Among the six detected ABCC9 missense variants, four [p. (Pro252Leu), p.(Thr259Lys), p.(Ala1064Pro), and p. (Arg1197His)] were novel. Systematic assessment of the clinical features in the nine cases with an ABCC9 variant highlights the significant clinical overlap between ZLS and CS that includes early developmental delay, hypertrichosis, gingival overgrowth, joint laxity, and hypoplasia of terminal phalanges and nails. Gain of K+ channel activity possibly accounts for significant clinical similarities of CS, ZLS and FHEIG syndrome and defines a new subgroup of potassium channelopathies.

We report on a girl, born to first cousin Lebanese parents, with intellectual disability, seizures, repeated gingivorrhagia, enlarged lower and upper jaws, overgrowth of the gums, high arched and narrow palate, crowded teeth, hirsutism of the back, large abdomen and a small umbilical hernia. Cysts of the mandible, fibrous dysplasia of bones, and enlarged adenoids causing around 60% narrowing of the nasopharyngeal airways were noted at radiographic examination. Her brother presented with the same features in addition to a short stature, an ostium secundum, and more pronounced intellectual disability. He died at the age of 8 years from a severe pulmonary infection and repeated bleeding episodes. A clinical diagnosis of Ramon syndrome was made. Whole exome sequencing studies performed on the family revealed the presence of a novel homozygous missense mutation in ELMO2 gene, p.I606S in the affected individuals. Loss of function mutations in ELMO2 have been recently described in another clinically distinct condition: primary intraosseous vascular malformation or intraosseous hemangioma, called VMOS. Review of the literature and differential diagnoses are discussed.

Hereditary gingival fibromatosis (HGF) is a highly genetically heterogeneous disease, and current therapeutic method is limited to surgical resection with a high recurrence rate. MicroRNAs (miRNAs) are able to fine-tune large-scale target genes. Here we established a simple but effective computational strategy based on available miRNA target prediction algorithms to pinpoint the most potent miRNA that could negatively regulate a group of functional genes. Based on this rationale, miR-335-3p was top ranked by putatively targeting 85 verified profibrotic genes and 79 upregulated genes in HGF patients. Experimentally, downregulation of miR-355-3p was demonstrated in HGF-derived gingival fibroblasts as well as in transforming growth factor β–stimulated normal human gingival fibroblasts (NHGFs) compared to normal control. Ectopic miR-335-3p attenuated, whereas knockdown of miR-335-3p promoted, the fibrogenic activity of human gingival fibroblasts. Mechanically, miR-335-3p directly targeted SOS1, SMAD2/3, and CTNNB1 by canonical and noncanonical base paring. In particular, different portfolios of fibrotic markers were suppressed by silencing SOS1, SMAD2/3, or CTNNB1, respectively. Thus, our study first proposes a novel miRNA screening approach targeting a functionally related gene set and identifies miR-335-3p as a novel target for HGF treatment. Mechanically, miR-335-3p suppresses the fibrogenic activity of human gingival fibroblasts by repressing multiple core molecules in profibrotic networks. Our strategy provides a new paradigm in the treatment for HGF as well as other diseases.

Idiopathic gingival fibromatosis (GF), also known as gingivomatosis, is a rare condition in childhood, with an unknown aetiology. The oral manifestations of the condition are varied and depend on the severity and age of involvement. This paper describe the case of a 5-year-old male child with extensive gingival enlargement covering almost all the maxillary and mandibular teeth resulted in difficulty with speech, mastication and poor aesthetics. Clinical and radiographic examination along with haematological investigations ruled out any systemic association. The case was managed with conventional scalpel blade surgery along with electrocautery under general anaesthesia yielding good results without any recurrence after a 12-month follow-up. The results revealed that the oral manifestations of GF depend on its severity and the age of onset. Timely intervention can help to prevent associated complications in a growing child.

Investigate the content of fibrotic fibrils in gingival tissue and the proliferation of fibroblasts collected from recurrent and non-recurrent hereditary gingival fibromatosis (HGF) and idiopathic gingival fibromatosis (IGF).Gingival biopsies were collected from HGF (n = 3) and IGF (n = 3) donors with recurrent and non-recurrent gingival overgrowths and from a control group (Ctrl, n = 3). Hematoxylin staining was performed to evaluate the histomorphology of gingival tissue. Heidenhain's AZAN trichrome staining served for visualization of fibrotic fibrils in gingiva. Quantitative analysis of the content of fibrotic fibrils in gingival tissue was performed using a polarized light microscope. Proliferation was evaluated at 24 h, 48 h, and 72 h in fibroblast cultures using a cell proliferation ELISA assay based on 5-bromo-2'-deoxyuridine (BrdU).Numerous blood vessels and fibroblasts were observed in recurrent overgrowths, whereas moderate blood vessels and moderate to scanty fibroblasts were detected in non-recurrent overgrowths. Heidenhain's staining revealed numerous collagen fibers in both recurrent and non-recurrent overgrowths. Quantitative analysis in a polarizing microscope showed significant accumulation of fibrotic fibrils exclusively in the overgrowths with the recurrence. In all time-points, increased proliferation of cells from all recurrent overgrowths was observed, but not from overgrowths which do not reoccur.The study revealed that recurrent gingival overgrowths consist of highly fibrotic and dense connective tissue with numerous blood vessels and abundant fibroblasts. We also demonstrated that unlike fibroblasts derived from overgrowths, which did not present recurrence, fibroblasts derived from highly fibrotic and recurrent overgrowths maintain high rate of proliferation in vitro.

Objectives Our study aims to identify genetic variants associated with hereditary gingival fibromatosis (HGF) by applying whole exome sequencing (WES) and bioinformatics analyses such as gene set enrichment analysis (GSEA) and protein functional network study. Subjects and Methods Two affected siblings whose grandparents and parents have normal gingiva were chosen for our investigation. Saliva collected from the patients and their parents were used for WES. GSEA and protein functional network study were performed to find gene groups in a biological coordination which are associated with HGF. Results Genetic variants for homozygotes and compound heterozygotes were analyzed and translated into 845 genes. The result from protein functional network study showed that these genetic variants were mainly observed in genes affecting fibronectin as well as the immune and auto-immune system. Additionally, three mutated genes in our HGF patients, TMCO1, RIN2, and INSR,were found through human phenotype ontology (HPO) to have potential to contribute to gingival hyperplasia. Conclusions Genetic analysis of HGF in this study implicated mutations in fibronectin and the immune system as triggering abnormal gingival fibromatosis. This article is protected by copyright. All rights reserved.

Aim. KCNH1 mutations have been identified in patients with Zimmermann-Laband syndrome and Temple-Baraitser syndrome, as well as patients with uncharacterized syndromes with intellectual disability and overlapping features. These syndromes include dysmorphic facial features, nail hypo/aplasia, thumb and skeletal anomalies, intellectual disability, and seizures. We report the epilepsy phenotype in patients with KCNH1 mutations.Methods. Demographic data, electroclinical features, response to antiepileptic drugs, and results of significant diagnostic investigations of nine patients carrying mutations in KCNH1 were obtained from referring centres.Results. Epilepsy was present in 7/9 patients. Both generalized and focal tonic-clonic seizures were observed. Complete seizure control was achieved with pharmacological treatment in 2/7 patients; polytherapy was required in 4/7 patients. Status epilepticus occurred in 4/7 patients. EEG showed a diffusely slow background in 7/7 patients with epilepsy, with variable epileptiform abnormalities. Cerebral folate deficiency and an increase in urinary hypoxanthine and uridine were observed in one patient.Conclusions. Epilepsy is a key phenotypic feature in most individuals with KCNH1-related syndromes, suggesting a direct role of KCNH1 in epileptogenesis, although the underlying mechanism is not understood.

Objective Hereditary gingival fibromatosis (HGF) is a rare oral disease characterized by either localized or generalized gradual, benign, non-hemorrhagic enlargement of gingivae. Although several genetic causes of HGF are known, the genetic etiology of HGF as a non-syndromic and idiopathic entity remains uncertain. Subjects and methods We performed exome and RNA-seq of idiopathic HGF patients and controls, and then devised a computational framework that specifies exomic/transcriptomic alterations interconnected by a regulatory network to unravel genetic etiology of HGF. Moreover, given the lack of animal model or large-scale cohort data of HGF, we developed a strategy to cross-check their clinical relevance through in silico gene-phenotype mapping with biomedical literature mining and semantic analysis of disease phenotype similarities. Results Exomic variants and differentially expressed genes of HGF were connected by members of TGF-β/SMAD signaling pathway and craniofacial development processes, accounting for the molecular mechanism of fibroblast overgrowth mimicking HGF. Our cross-check supports that genes derived from the regulatory network analysis have pathogenic roles in fibromatosis-related diseases. Conclusions The computational approach of connecting exomic and transcriptomic alterations through regulatory networks is applicable in the clinical interpretation of genetic variants in HGF patients.

Although hereditary gingival fibromatosis is a rare condition, it leaves unrestroable psychological, esthetical as well as functional problems to the affected patients. The purpose of the current research is to find a non-surgical pharmacological mechanism that could provide a control of the active phase of such disease helping individual to continue their lives.

Objectives To investigate the processes associated with the excessive production of collagen I in hereditary gingival fibromatosis (HGF). Materials and methods Three HGF subjects and five controls were enrolled in the study. Histomorphological and immunohistological analyses were performed on gingival tissues. The expression of heat-shock protein 47 (HSP47), collagen I, transforming growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF), matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) by gingival fibroblasts isolated from HGF and controls was analysed using qRT-PCR, Western blotting and ELISA. Results Considerable accumulation of fibrotic fibrils and increased synthesis of HSP47 were noted in HGF gingival tissues. The synthesis of collagen I, HSP47, TGF-β1, CTGF and TIMP-1 was significantly elevated in HGF gingival fibroblasts compared with controls, while the production of MMP-1 was decreased. Conclusions We report that fibrosis in HGF gingival tissues is associated with increased synthesis of HSP47. This finding was confirmed by an in vitro study, where excessive production of collagen I was associated with increased synthesis of HSP47, TGF-β1 and CTGF by HGF gingival fibroblasts. Moreover, the shift in the TIMP-1/MMP-1 ratio identifies increased synthesis of TIMP-1 as one of the processes associated with collagen I overproduction in HGF fibroblasts.

Generalized hypertrichosis is a feature of several genetic disorders, and the nosology of these entities is still provisional. Recent studies have implicated chromosome 17q24.2–q24.3 microdeletion and the reciprocal microduplication in a very rare form of congenital generalized hypertrichosis terminalis (CGHT) with or without gingival hyperplasia. Here, we report on a 5-year-old Egyptian girl born to consanguineous parents. The girl presented with CGHT and gingival hyperplasia for whom we performed detailed clinical, pathological, and molecular studies. The girl had coarse facies characterized by bilateral epicanthic folds, thick and abundant eyelashes, a broad nose, full cheeks, and lips that constituted the distinctive facial features for this syndrome. Biopsy of the gingiva showed epithelial marked acanthosis and hyperkeratosis with hyperplastic thick collagen bundles and dense fibrosis in the underlying tissues. Array analysis indicated a 17q24.2–q24.3 chromosomal microdeletion. We validated this microdeletion by real-time quantitative PCR and confirmed a perfect co-segregation of the disease phenotype within the family. In summary, this study indicates that 17q24.2–q24.3 microdeletion caused CGHT with gingival hyperplasia and distinctive facies, which should be differentiated from the autosomal recessive type that lacks the distinctive facies. © 2015 Wiley Periodicals, Inc.

Congenital generalized hypertrichosis associated with gingival hyperplasia are rare cases published in literature. The frequency incidence of generalized congenital hypertrichosis is about one to billions of people. Hypertrichosis and gingival hyperplasia are termed as Ambras syndrome (AS), which can be noticed at birth or soon after. Here, is a rare case report of 4-year-old male child who presented with generalized hypertrichosis with gingival fibromatosis and dysmorphic facial features.

This case compared gene-expression between a new type of idiopathic gingival fibromatosis (IGF) and normal gingiva, to clarify the nature of the gingival overgrowth and dental anomaly. A 6-year-old girl with generalized gingival overgrowth and root deformations was diagnosed with IGF. Gene expression profiles were compared between normal gingiva (N=9) and one IGF gingiva using cDNA microarray. Genes related to regulation of cell proliferation and proteolytic degradation were expressed strongly in IGF. MMP-13 and MMP-12 expression were 120 times and 96 times lower in IGF, respectively, whereas AMBN expression was 79 times higher. RT-PCR and immunohistochemical staining supported the microarray results. Reduced proteolytic activity due to low MMP-13 and MMP-12 expression appears to be a potential mechanism for gingival overgrowth. Genetic investigations, such as expression levels of MMP-13, MMP-12, and AMBN, may enable classification of a new syndrome characterized by gingival enlargement with abnormal root development.

Microdeletions of 17q24.2-q24.3 have been described in several patients with developmental and speech delay, growth retardation, and other features. The relatively large size and limited overlap of the deletions complicate the genotype-phenotype correlation. We identified a girl with intellectual disability, growth retardation, dysmorphic features, and a de novo 2.8 Mb long deletion of 17q24.2-q24.3. Her phenotype was strikingly similar to one previously described boy with Dubowitz syndrome (MIM 223370) and a de novo 3.9 Mb long deletion encompassing the deletion of our patient. In addition, both patients had the shortest telomeres among normal age-matched controls. Our review of all 17q24.2-q24.3 deletion patients revealed additional remarkable phenotypic features shared by the patients, some of which have consequences for their management. Proposed novel genotype-phenotype correlations based on new literature information on the region include the role of PSMD12 and BPTF, the genes recently associated with syndromic neurodevelopmental disorders, and a possible role of the complex topologically associated domain structure of the region, which may explain some of the phenotypic discrepancies observed between patients with similar but not identical deletions. Nevertheless, although different diagnoses including the Dubowitz, Nijmegen breakage (MIM 251260), Silver-Russell (MIM 180860), or Myhre (MIM 139210) syndromes were originally considered in the 17q24.2-q24.3 deletion patients, they clearly belong to one diagnostic entity defined by their deletions and characterized especially by developmental delay, specific facial dysmorphism, abnormalities of extremities and other phenotypes, and possibly also short telomere length.

Hereditary gingival fibromatosis (HGF) is the most common genetic form of gingival fibromatosis that develops as a slowly progressive, benign, localized or generalized enlargement of keratinized gingiva. HGF is a genetically heterogeneous disorder and can be transmitted either as an autosomal-dominant or autosomal-recessive trait or appear sporadically. To date, four loci (2p22.1, 2p23.3–p22.3, 5q13–q22, and 11p15) have been mapped to autosomes and one gene ( SOS1 ) has been associated with the HGF trait observed to segregate in a dominant inheritance pattern. Here we report 11 individuals with HGF from three unrelated families. Whole-exome sequencing (WES) revealed three different truncating mutations including two frameshifts and one nonsense variant in RE1-silencing transcription factor ( REST ) in the probands from all families and further genetic and genomic analyses confirmed the WES-identified findings. REST is a transcriptional repressor that is expressed throughout the body; it has different roles in different cellular contexts, such as oncogenic and tumor-suppressor functions and hematopoietic and cardiac differentiation. Here we show the consequences of germline final-exon-truncating mutations in REST for organismal development and the association with the HGF phenotype.

Familial growth hormone deficiency provides an opportunity to identify new genetic causes of short stature. Here we combine linkage analysis with whole-genome resequencing in patients with growth hormone deficiency and maternally inherited gingival fibromatosis. We report that patients from three unrelated families harbor either of two missense mutations, c.347G>T p.(Arg116Leu) or c.1106C>T p.(Pro369Leu), in KCNQ1, a gene previously implicated in the long QT interval syndrome. Kcnq1 is expressed in hypothalamic GHRH neurons and pituitary somatotropes. Co-expressing KCNQ1 with the KCNE2 β-subunit shows that both KCNQ1 mutants increase current levels in patch clamp analyses and are associated with reduced pituitary hormone secretion from AtT-20 cells. In conclusion, our results reveal a role for the KCNQ1 potassium channel in the regulation of human growth, and show that growth hormone deficiency associated with maternally inherited gingival fibromatosis is an allelic disorder with cardiac arrhythmia syndromes caused by KCNQ1 mutations., Growth retardation is most commonly caused by genetic defects in the growth hormone pathway. Here, in families with growth retardation and gingival fibromatosis, the authors identify mutations in the potassium channel gene KCNQ1 that cause electrophysiological aberrations and altered ACTH secretion in vitro.

Hereditary hyperplastic gingivitis (HHG) is an autosomal recessive disease that presents with progressive gingival proliferation in farmed silver foxes. Hereditary gingival fibromatosis (HGF) is an analogous condition in humans that is genetically heterogeneous with several known autosomal dominant loci. For one locus the causative mutation is in the Son of sevenless homologue 1 (SOS1) gene. For the remaining loci, the molecular mechanisms are unknown but Ras pathway involvement is suspected. Here we compare sequences for the SOS1 gene, and two adjacent genes in the Ras pathway, growth receptor bound protein 2 (GRB2) and epidermal growth factor receptor (EGFR), between HHG-affected and unaffected foxes. We conclude that the known HGF causative mutation does not cause HHG in foxes, nor do the coding regions or intron–exon boundaries of these three genes contain any candidate mutations for fox gum disease. Patterns of molecular evolution among foxes and other mammals reflect high conservation and strong functional constraints for SOS1 and GRB2 but reveal a lineage-specific pattern of variability in EGFR consistent with mutational rate differences, relaxed functional constraints, and possibly positive selection.

The enamel-renal syndrome of amelogenesis imperfecta (AI) and nephrocalcinosis, and the amelogenesis imperfecta-gingival fibromatosis syndrome have both been associated with mutations in FAM20A. We report on two unrelated Thai patients with three novel and one previously reported mutations in FAM20A with findings suggesting both disorders, including hypoplastic AI, gingival fibromatosis, unerupted teeth, aggressive periodontitis, and nephrocalcinosis/nephrolithiasis. Additional findings consisted of a supernumerary premolar, localized aggressive periodontitis, thin alveolar bone, vitamin D deficiency-associated hyperparathyroidism, and heterotopic calcification in other tissues, including lungs, dental pulp, gingiva, dental follicles, and periodontal tissues, and early cessation of limited menstruation. Greater promotory activity of urine on calcium oxalate crystal growth compared to controls may help to explain the pathogenesis, and suggest that FAM20A mutations can contribute to nephrocalcinosis/nephrolithiasis. Our findings expand the phenotypic spectrum of FAM20A mutations. Since both of our patients and a large number of previously reported cases had all the important features of both syndromes, including AI, renal anomalies, and gingival fibromatosis, we are convinced that these two disorders actually are the same entity. The name of enamel-renal-gingival syndrome is suggested. © 2013 Wiley Periodicals, Inc.

We present a case of both unusual pathology and severity – giant maxillary gingival fibromatosis – and discuss the disease and its management, accompanied by clinical imaging. This represents an overlap between maxillofacial and oral surgery, and may present as demonstrated in this case.

Since the 1940s, a proliferative gingival disease called hereditary hyperplastic gingivitis (HHG) has been described in the farmed silver fox, Vulpes vulpes (Dyrendahl and Henricson 1960). HHG displays an autosomal recessive transmission and has a pleiotropic relationship with superior fur quality in terms of length and thickness of guard hairs. An analogous human disease, hereditary gingival fibromatosis (HGF), is characterized by a predominantly autosomal dominant transmission and a complex etiology, occurring either as an isolated condition or as a part of a syndrome. Similar to HHG, the symptom most commonly associated with syndromic HGF is hypertrichosis. Here we explore potential mechanisms involved in HHG by comparison to known genetic information about hypertrichosis co-occurring with HGF, using an Affymetrix canine genome microarray platform, quantitative PCR, and candidate gene sequencing. We conclude that the mitogen-activated protein kinase pathway is involved in HHG, however despite involvement of the mitogen-activated protein kinase kinase 6 gene in congenital hypertrichosis with gingival fibromatosis in humans, this gene did not contain any fixed mutations in exons or exon-intron boundaries in HHG-affected foxes, suggesting that it is not causative of HHG in the farmed silver fox population. Differential up-regulation of MAP2K6 gene in HHG-affected foxes does implicate this gene in the HHG phenotype.

Background KCNH1 encodes a voltage-gated potassium channel that is predominantly expressed in the central nervous system. Mutations in this gene were recently found to be responsible for Temple-Baraitser Syndrome (TMBTS) and Zimmermann-Laband syndrome (ZLS). Methods Here, we report a new case of TMBTS diagnosed in a Lebanese child. Whole genome sequencing was carried out on DNA samples of the proband and his parents to identify mutations associated with this disease. Sanger sequencing was performed to confirm the presence of detected variants. Results Whole genome sequencing revealed three missense mutations in TMBTS patient: c.1042G > A in KCNH1, c.2131 T > C in STK36, and c.726C > A in ZNF517. According to all predictors, mutation in KCNH1 is damaging de novo mutation that results in substitution of Glycine by Arginine, i.e., p.(Gly348Arg). This mutation was already reported in a patient with ZLS that could affect the connecting loop between helices S4-S5 of KCNH1 with a gain of function effect. Conclusions Our findings demonstrate that KCNH1 mutations cause TMBTS and expand the mutational spectrum of KCNH1 in TMBTS. In addition, all cases of TMBTS were reviewed and compared to ZLS. We suggest that the two syndromes are a continuum and that the variability in the phenotypes is the result of the involvement of genetic modifiers.

Gingival fibromatosis (GF) is a condition characterized by a progressive, normal colored enlargement of the gingiva caused by an increase in the size of submucosal connective tissue. Both familial and idiopathic variants of the condition exist. The authors present a case report of a 38-year-old African American man who presented with an impressive overgrowth of the maxillary and mandibular gingivae, subsequently diagnosed as idiopathic GF. In this report, the authors will review the etiologies, treatment, and clinical and histological findings of GF, review similar cases found in the literature, and discuss the differential diagnosis for diffuse gingival enlargements.

Patient: Female, 11 Final Diagnosis: Hereditary gingival fibromatosis Symptoms: Gingival overgrowth Medication: — Clinical Procedure: Surgery Specialty: Dentistry Objective: Rare disease Background: Hereditary gingival fibromatosis is characterized by slowly progressive enlargement of the gingiva that can present as an isolated condition or a part of various syndromes. Case Report: An 11-year-old female reported with a gingival lesion that caused masticatory problems and poor oral hygiene. Periodontal examination revealed a dense tissue covering 30% of her teeth crowns within both jaws. Panoramic x-ray showed a normal bone height and teeth positioning. The patient did not use any medications, but a similar condition was also present in other family members. The patient was diagnosed with hereditary gingival fibromatosis. Surgery was carried out to remove excess of gingival tissue. Post-surgical healing was uneventful, but four weeks after the first surgery, the condition recurred amounting to 45% of the initial tissue volume presenting in the mandible, and 25% in the maxilla. Two months later, no significant growth was noted in the mandible, while in the maxilla, growth increased to 40% of the pre-operative state. Analysis by polarized microscope showed a significant increase of thin fibrotic fibrils that contributed 80% of the total pool of collagen fibrils in the patient’s gingiva, but only 25% in healthy gingiva. The patient was receiving outpatient care for follow-up every three months and surgical intervention had not been planned as long as her periodontal health would not be compromised. Conclusions: It is currently not clear whether the extent of the fibrosis had a mechanistic association with the ratio of gingival tissue re-growth in our case study. Further studies are needed to explain this association and improve the management of this condition.

We present an 11-year-old girl with a 2.3 Mb de novo interstitial deletion in chromosome 17q24.2-q24.3 identified by array CGH. The phenotype in this case includes skeletal malformations (lower limb bowing, progressive scoliosis and dental abnormalities), feeding problems, mild learning difficulties, and a characteristic facial appearance. Much of the phenotype is attributable to the deletion of KCNJ2, which causes Andersen Tawil Syndrome (ATS), but the facial appearance is not typical. We hypothesise that the presence of mild channelopathy-related features seen in ATS may be explained by haplo-insufficiency, leading to a reduced number of functionally normal Kir2.1 channels. Comparison is made to previous reports describing overlapping 17q deletions, and potential candidate genes which account for the specific phenotypic similarities with this case are highlighted.

Objectives: Hereditary Gingival Fibromatosis (HGF) is a rare benign fibrous lesion of the gingival tissues presumably caused by single gene defects. The aim of this study was to identify the genetic defect leading to HGF in an extended pedigree. Materials and Methods: We report the clinical features and genetic analysis of a family affected by HGF. A total of 17 subjects were assessed clinically and had blood samples taken for DNA extraction. Multipoint parametric linkage analysis was performed to identify the possible chromosomal location responsible for HGF in this family. Results: Presence of severe HGF associated with tooth impaction was confirmed for seven members of this three-generation family. Linkage analysis revealed that loci on chromosomes 7, 10, 13, 15, 16, 17, 19 and 20 were linked to this trait. Previously found mutations in the SOS1 and GINGF loci were therefore excluded by this analysis. Conclusions: This study brings further evidence for genetic heterogeneity of HGF and points towards the existence of different, not-yet-identified genes linked to this condition. © 2012 John Wiley & Sons A/S.

Juvenile hyaline fibromatosis (JHF) and infantile systemic hyalinosis (ISH) are rare, autosomal recessive disorders of the connective tissue caused by mutations in the gene encoding the anthrax toxin receptor 2 protein (ANTXR2) located on chromosome 4q21. Characteristically, these conditions present with overlapping clinical features, such as nodules and/or pearly papules, gingival hyperplasia, flexion contractures of the joints, and osteolytic bone defects. The present report describes a pair of sibs and three other JHF/ISH patients whose diagnoses were based on typical clinical manifestations and confirmed by histopathologic analyses and/or molecular analysis. A comparison of ISH and JHF, additional thoughts about new terminology (hyaline fibromatosis syndrome) and a modified grading system are also included.

Several forms of hypertrichosis have been described with and without gingival hyperplasia; some of them are recognized as genetic disorder and associated with syndromes. In all reported cases the most striking differences from other are the craniofacial features. We present a case of a 6-year-old boy with hypertrichosis associated with gingival hyperplasia and a characteristic, coarse face and we consider this case to be a distinctive entity.

©2011 Ethis Communications, Inc. The Ocular Surface ISSN: 1542-0124. Murube J. Primary and secondary SjogrenJones syndromes—historical evolution. 2011;9(1):13-16. ccording to Norman Talal, the history of Sjogren syndrome (SS) can be divided into three phases: clinical (1888-1950), immunologic, and molecular.1 The concept of primary and secondary Sjogren syndrome developed during the transition between the second and third phases. In the last 50 years, since the publications of Jones,2 Bunim,3 and Bloch et al,4 most clinicians and researchers have accepted that SS refers to SS of autoimmune etiopathogenesis, or Sjogren-Jones syndrome. The recognition of the autoimmune basis of the disease opened a new clinical approach.5 The polymorphism of the SSs stimulated several classifications and subclassifications. In 1961, Sjogren6 had already accepted the possible auto-immunologic cause of the sicca syndrome suggested by Jones, Bloch et al, and Bunim,2-4 and he determined that the autoimmunopathies should be divided into collagenoses and adenopathies and that these groups could exist alone or together in various combinations. Clinical differences in SS in the absence or presence of rheumatoid arthritis and of systemic lupus erythematosus had been noted by many clinicians.7-21 The division into primary and secondary SSs had many antecedents, and in 1979 became universally accepted with the publications of Moutsopoulos.22,23 In medical terminology, primary and secondary designations may have several different bases, and have been variously used. In the case of SSs, primary does not mean that it is the origin of the secondary or that it is of more importance than the secondary. In the current terminology of SS, primary and secondary refer to two different etiopathogenic groups or types. De Cremoux et al preferred to say limited rather than primary SS in order to avoid the confusion of the terms.24 Ancochea et al preferred to name these two groups primary and associated SS, the latter being associated with autoimmune diseases and connectivopathies.25 The Triple Classification of Dry Eye proposed describing secondary SS as “SS associated with...” followed by the specific association. This is because sometimes this association is not autoimmunologic, but derives from hormonal, viral, or other causes, or is simply coincident with SS exocrinopathy.26,27 Some authors consider this expression the most appropriate to describe the clinical profile of an SS patient.28

INTRODUCTION: Gingiva fibromatosis is a relatively rare condition characterized by diffuse enlargement of the gingiva, which is caused by expansion and accumulation of the connective tissue. OBJECTIVE: The aim of the present study was to investigate proliferative and apoptotic biomarker expression in normal gingiva and two forms of gingival fibromatosis. METHODS: Archived tissue specimens of hereditary gingival fibromatosis, gingival fibromatosis and dental abnormality syndrome and normal gingiva were subject to morphological analysis and immunohistochemical staining. The results were analyzed statistically. RESULTS: Proteins associated with proliferation were found in the nuclei of epithelial cells from the basal and suprabasal layers, whereas apoptotic proteins were detected in the cytoplasm of the upper layers of the epithelium. Increased expressions of minichromosome maintenance proteins 2 and 5 were observed in the gingival fibromatosis and dental abnormality syndrome samples. In contrast, geminin expression was higher in normal gingiva samples. No difference in the expression of apoptotic proteins was observed among the groups. CONCLUSION: Our findings support a role for augmented proliferation of epithelial cells within the overgrown tissues associated with gingival fibromatosis or dental abnormality syndrome. However, our data suggest that different biological mechanisms may account for the pathogenesis of different types of gingival fibromatosis.

R Molluscum fibrosum,” a variant of the neurofibromaosis disorders, was first described by Murray in 873. However, in 1973 it was Kitano et al who enamed the disease “juvenile hyaline fibromatosis” JHF). There have been approximately 70 cases of JHF eported in the literature to date. JHF is a rare autosomal dominant systemic disease f the connective tissue, typically presenting in childood. In 2002, Rahman et al performed a genetic nalysis of 2 families with JHF and linked JHF to a utation on chromosome 4q21. The exact underlying athogenesis of JHF is yet to be identified, but some nvestigators have proposed it results from an abnor

Zimmermann-Laband syndrome is a rare disorder characterized by gingival fibromatosis, abnormalities of the nose and/or ears, absence and/or hyperplasia of the nails or terminal phalanges of the hands and feet, hyperextensibility of joints, hepatosplenomegaly, mild hirsutism and mental retardation. The syndromic characteristics of Zimmermann-Laband syndrome are highly variable and complicated. This paper described a patient with Zimmermann-Laband syndrome with new manifestations and discusses the possible underlying genetic mechanisms.

Cherubism is an inherited, autosomal dominant disorder that characteristically affects the jaws of children. The disease typically manifest as a bilateral swelling with associated submandibular lymph node enlargements and usually regresses as age advances. The disease is microscopically indistinguishable from other giant cell lesions and is essentially a clinical diagnosis. The association of cherubism with gingival fibromatosis, epilepsy, mental retardation, stunted growth, and hypertrichosis is referred as Ramon syndrome. We report a case of Ramon syndrome in an 8 year old girl.

Background and Objective: Hereditary gingival fibromatosis (HGF) is a benign disorder manifested by fibrous enlargement of keratinized gingiva. Evidence exists concerning the role of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in mediating normal and pathological processes, including HGF. Nevertheless, there are few and contradictory results on the analysis of MMPs and TIMPs transcripts in this pathology. Material and Methods: We studied the expression of the transcripts encoding MMP-1, -2 and -9 and TIMP-1 and -2 in gingival biopsies, obtained from three cases of HGF within a family, by semi-quantitative reverse transcriptase-polymerase chain reaction analysis. Samples were also processed for gelatin zymography. Results: Except for MMP-9, most transcripts presented a higher level of expression in biopsies from HGF patients compared with control subjects. Accordingly, MMP-9 gelatinase activity was detected at low and similar levels among samples. Moreover, MMP-2 enzymatic activity was not detected at all. Conclusion: The mRNA expression of MMP-1 and -2 and TIMP-1 and -2 does not explain the gingival overgrowth presented in these cases. In addition, it is suggested that the gene expression of those molecules in the course of HGF is regulated at the translational or post-translational level.

Glycosaminoglycans (GAGs) play important roles in cell behavior and have the ability to bind and modulate cytokines. Using primary cultured fibroblasts from hereditary gingival fibromatosis (HGF), normal gingiva (NG), and NG treated with cyclosporin-A (NGc) we show changes in the expression and structural characteristics of GAGs as well as in the expression of enzymes involved in their biosynthesis and degradation. In addition, we show the over-expression of TGF-beta1 and TGF-beta type II receptor in HGF and NGc. There is an increase in the GAGs retained in the cellular fraction, and the fine structure of galactosaminoglycans show a decrease in alpha-l-iduronic acid content in HGF and NGc. Elevated extracellular levels of low molecular weight hyaluronan (HA) are found in HGF due to increase in the expression of HA synthase 3 and hyaluronidases 1 and 2. The results bring new insights to the accumulation of extracellular matrix related to TGF-beta over-expression.

Juvenile hyaline fibromatosis (JHF) is a rare autosomal-recessive hereditary disease, characterized by gingival hypertrophy, flexion contractures of joints, bone lesions, hyaline deposition in the extracellular spaces of the dermis and soft tissues, stunted growth, and skin lesions such as multiple nodules, tumors and pink, pearly papules. No case of JHF with a mandibular bone involvement, exists in the literature. Bone involvement in JHF is an uncommon finding and distinct solitary lesions in the calvarial bones has been reported by some authors. A 21-year-old male patient was referred to Diyarbakir Military Hospital, Department of Dental Service. Clinical findings were consistent with a solid alveolar mass in the right mandibular premolar-molar region and displaced right mandibular molar teeth. Orthopantomographic examination showed impaction of all lower right molars in a mixed radioopaque/radiolucent area. Microscopically, increased nodular connective tissue was seen under the lobulated mucosal surfaces of the resected area. The case presented here had a localized fibrous proliferation that infiltrated bone trabeculae and caused displacement of teeth. Juvenile hyaline fibromatosis should be considered in the differential diagnosis with the other intraosseous radiolucent-patchy opaque lesions of jaw bones. Based on the clinical and histopathological findings, a diagnosis of JHF was made.

The objective of the study was to overview the role of genetic research in fostering translational studies of craniofacial diseases of dental interest. Background information is presented to illustrate influences affecting genetic research studies of Mendelian diseases. Genetic studies of amelogenesis imperfecta, dentinogenesis imperfecta, hereditary gingival fibromatosis and Papillon Lefèvre syndrome are reviewed. Findings are presented to illustrate how translational applications of clinical and basic research may improve clinical care. Clinical and basic science research has identified specific genes and mutations etiologically responsible for amelogenesis imperfecta, dentinogenesis imperfecta, hereditary gingival fibromatosis and Papillon Lefèvre syndrome. These findings are enabling researchers to understand how specific genetic alterations perturb normal growth and development of dental tissues. Identification of the genetic basis of these conditions is enabling clinicians and researchers to more fully understand the etiology and clinical consequences of these diseases of dental importance. Findings from genetic studies of dental diseases provide a basis for diagnostic genetic testing and development of therapeutic intervention strategies directed at the underlying disease etiology. These studies are advancing our understanding of the development of dental tissues in health and disease. The dental community must consider how to incorporate these developments into effective disease prevention paradigms to facilitate the diagnosis and treatment of individuals with genetic diseases.

The Central Institute for Stomatology and Maxillo-facial Surgery in Moscow is one the main centers for the treatment of pediatric head and neck tumors in the territory of the former Soviet Union. A series of 33 patients presenting with cherubism (24 children and 9 of their parents) is presented. The authors discuss the atypical clinical presentations, the relevant associated anomalies and the different treatment strategies. They report the first case of cherubism associated with gingival hypertrophy without neurological signs.

SUMMARY Gingival fibromatosis, a rare but often familial condition, is described in two siblings, associated with mental retardation, epilepsy and hypertrichosis. In one child a maxillary giant-cell tumour was found and excised. It is important to distinguish idiopathic gingival fibromatosis from phenytoin-induced gingival hypertrophy. RESUME Fibromatose gingivale familiale idiopathique associee a un retard mental, une epilepsie et une hypertrichose La fibromatose gingivale, une affection rare et souvent familiale, est decrite chez deux enfants de meme fratrie, en association avec un retard mental, une epilepsie et une hypertrichose. Chez l'un des enfants, une tumeur maxillaire a cellules geantcs fut depistee et excisee. II est important de distinguer la fibromatose gingivale idiopathique de l'hypertrophie gingivale liee au traitement par phenytoine. ZUSAMMENFASSUNG Idiopathische, familiare Gingivafibromatose mit geistiger Retardierung, Epilepsie und Hypertrichose Die Gingivafibromatose, eine seltene, aber haufig familiar auftretende Erkrankung, wird bei zwei Geschwistern in Verbindung mit geistiger Retardierung, Epilepsie und Hypertrichose beschrieben. Bei einem Kind wurde ein maxillarer Riesenzelltumor gefunden und exzidiert. Es ist wichtig, die idiopathische Gingivafibromatose von der Phenytoin bedingten Gingivahypertrophie zu unterscheiden. RESUMEN Fibromatosis gingival familiar idiopdtica asociada a retraso mental, epilepsia e hipertricosis Se describe en dos ninos una gingivitis fibromatosa, alteracion rara pero a menudo familiar, asociada a retraso mental, epilepsia e hipertricosis. En un nino se hallo y extirpo un tumor maxilar de celulas gigantes. Es importante distinguir la fibromatosis gingival idiopatica de la hipertrofia gingival debida a la fenitoina.

Gingival fibromatosis (GF) is characterized by fibrotic enlargement of the gingiva that can be inherited as an isolated trait (named hereditary gingival fibromatosis) or as a component of a syndrome. This article reports one kindred affected by a syndrome characterized by GF associated with dental abnormalities (DA) including generalized thin hypoplastic amelogenesis imperfecta (AI).To characterize the pattern of inheritance and the clinical features, 70 family members were examined. Hematoxylin and eosin staining, immunohistochemistry, and scanning electronic microscopy (SEM) were performed to identify the alterations on gingiva, teeth, and dental follicles.Examination of the family pedigree demonstrated multiple consanguineous first-cousin marriages and an autosomal recessive trait of inheritance. Four members demonstrated mild GF in association with DA, including generalized thin hypoplastic AI, intrapulpal calcifications, delay of tooth eruption, and pericoronal radiolucencies involving unerupted teeth. One of those four patients also had mental retardation (MR). MR as an isolated feature was observed in six members, whereas isolated GF was found in one individual. A combination of gingivectomy and gingivoplasty followed by regular dental procedures were performed in these patients. Histologic examination of the gingival enlargement revealed a dense connective tissue containing myofibroblasts, islands of odontogenic epithelium, and calcified psammomatous deposits, which resembled cementicle-like structures by SEM. Pericoronal lesions also showed calcified psammomatous deposits in association with islands of odontogenic epithelium. Enamel ultrastructure analysis revealed normal surface alternating with irregular and porous areas.To the best of our knowledge, these cases represent a new syndrome within the spectrum of those including GF.