On the Cellular and Molecular Mechanisms of Drug-Induced Gingival Overgrowth

Areca nut-induced oral fibrosis - Reassessing the biology of oral submucous fibrosis

BACKGROUND

Oral submucous fibrosis (OSF) is a pathological condition characterized by excessive tissue healing resulting from physical, chemical, or mechanical trauma. Notably, areca nut consumption significantly contributes to the development of oral fibrosis. The current definition of OSF, recognizing its potential for malignant transformation, necessitates a more comprehensive understanding of its pathophysiology and etiology.

HIGHLIGHTS

Areca nut induces fibrotic pathways by upregulating inflammatory cytokines such as TGF-β and expressing additional cytokines. Moreover, it triggers the conversion of fibroblasts to myofibroblasts, characterized by α-SMA and γSMA expression, resulting in accelerated collagen production. Arecoline, a component of areca nut, has been shown to elevate levels of reactive oxygen species, upregulate the expression of various cytokines, and activate specific signaling pathways (MEK, COX2, PI3K), all contributing to fibrosis. Therefore, we propose redefining OSF as "Areca nut-induced oral fibrosis" (AIOF) to align with current epistemology, emphasizing its distinctive association with areca nut consumption. The refined definition enhances our ability to develop targeted interventions, thus contributing to more effective prevention and treatment strategies for oral submucous fibrosis worldwide.

CONCLUSION

Arecoline plays a crucial role as a mediator in fibrosis development, contributing to extracellular matrix accumulation in OSF. The re-evaluation of OSF as AIOF offers a more accurate representation of the condition. This nuanced perspective is essential for distinguishing AIOF from other forms of oral fibrosis and advancing our understanding of the disease's pathophysiology.

Drug induced gingival enlargement - phenytoin: an overview and case report

Gingival enlargement is a side effect of several different medication, including immunosuppressants, anticonvulsants, and calcium channel blockers. It is an inflammatory response that starts when plaque and calculus build up on the tooth surface. The most prevalent long-term neurological condition affecting people is epilepsy. In affluent nations, the prevalence of epilepsy is ~ 1%, whereas in less developed countries, it may >2%. The preferred medication for the condition, phenytoin, has major side effects include gingival enlargement. In addition to being visually disfiguring, this enlargement frequently affects speech, chewing and eating. Furthermore, those with poor dental hygiene, causes disabilities with motor coordination and muscular limitations leading to mental disability and physical impairments are more prone to periodontal disease. This article enlightened the mechanism of drug induced gingival enlargement clinically, microbiologically, and surgically.

Ulectomy in a patient with nephrotic syndrome under investigation for Galloway-Mowat syndrome: a case report

The aim of this study is to report a case in which a patient with nephrotic syndrome underwent surgery to remove fibrous gum tissue (ulectomy). An 8-year-old patient, diagnosed with early onset nephrotic syndrome due to a mutation in the NUP107 gene, had received a kidney transplant and was therefore taking various medications, including immunosuppressants. On oral examination, the patient was found to have a fibrous gingiva that was preventing the eruption of the upper permanent central incisors. A ulectomy was performed and the gingival tissue was sent for histopathological analysis, which showed normal aspects. The upper right central incisor was seen in the oral cavity 15 days after surgery. A second procedure was carried out to facilitate the eruption of the upper left incisor, which was visualized in the oral cavity 30 days later. In addition, oral manifestations such as maxillary atresia, ogival palate and mouth breathing were observed. Therefore, the role of the dental surgeon in the lives of transplanted children is considered important, as they often take various medications that can affect their oral health. Thus, early diagnosis and effective treatment will be essential to prevent future malocclusions and thus improve the quality of life of these patients.

Calcium Channel Blockers- Induced Iatrogenic Gingival Hyperplasia: Case Series

Hypertension rightfully termed as "Silent killer" is associated with increase in morbidity and mortality when left untreated. Calcium channel blockers are the most commonly prescribed first-line anti-hypertensive drugs in India. Calcium channel blockers are known to cause gingival hyperplasia but with lower incidence rates compared to the other two groups causing iatrogenic gingival overgrowth, immunosuppressants, and anticonvulsants. Nifedipine administration, among the calcium channel blockers, has been frequently associated with iatrogenic gingival hyperplasia. Incidence of amlodipine-induced gingival hyperplasia which has similar pharmacodynamic action like nifedipine, had been reported rarely. Here, we present a case series of drug induced gingival overgrowth caused by calcium channel blockers used for the management of hypertension. All the patient's condition improved after withdrawal of the offending drug, oral prophylaxis and intervention, and alternate drug from other first-line drugs were started for managing hypertension.

Cyclosporine-Induced Gingival Hyperplasia in a Patient With Lichen Planopilaris: Misfortunes Never Come Singly!

Cyclosporine A constitutes an immunosuppressive medication administered against various autoimmune and autoinflammatory disorders as well as against graft versus host disease. Its most well-known oral adverse effect is gingival hyperplasia. The aim of this study is to report a persistent case of a patient with lichen planopilaris with alopecia treated with cyclosporine leading to the manifestation of gingival hypertrophy. A female patient aged 38 years old was referred to the Department of Oral Medicine/Pathology, Dental School, Aristotle University of Thessaloniki, Greece complaining about gum bleeding, halitosis, and a persistent gingival enlargement, which appeared two months ago. According to her medical history, lichen planopilaris was diagnosed six months ago and was initially treated for 40 days with methylprednisolone 16 mg twice per day without improvement, and was replaced by cyclosporine A 200 mg per day. The clinical oral examination revealed gingival enlargement at areas #34-43, 22-23, and 25-27 without any lesion of lichen planus. The level of oral hygiene was satisfactory, with a limited amount of tartar and plaque. Bleeding on probing was also noticed, and pseudopockets of 5 mm were observed. The serum levels of cyclosporine were 473,60 μg/L, with a normal range, regarding repercussions in the oral cavity, up to 200 μg/L. A decrease of cyclosporine dosage to 150 mg was performed. After 15 days, the clinical appearance significantly improved, and a biopsy was done. The microscopic findings showed mild ulceration and inflammatory infiltrates, together with the abundant presence of collagen stroma, without any sign of malignancy. According to the literature, the high dosage of cyclosporine, its relevant high serum levels, and the presence of plaque were responsible for the manifestation of gingival hypertrophy.

Drug-Induced Gingival Overgrowth—Molecular Aspects of Drug Actions

Drug-induced gingival overgrowth (DIGO) is one of the side effects produced by therapeutic agents, most commonly phenytoin, nifedipine and cyclosporin A. However, the precise mechanism of DIGO is not entirely understood. A literature search of the MEDLINE/PubMed databases was conducted to identify the mechanisms involved in DIGO. The available information suggests that the pathogenesis of DIGO is multifactorial, but common pathogenic sequelae of events emerge, i.e., sodium and calcium channel antagonism or disturbed intracellular handling of calcium, which finally lead to reductions in intracellular folic acid levels. Disturbed cellular functions, mainly in keratinocytes and fibroblasts, result in increased collagen and glycosaminoglycans accumulation in the extracellular matrix. Dysregulation of collagenase activity, as well as integrins and membrane receptors, are key mechanisms of reduced degradation or excessive synthesis of connective tissue components. This manuscript describes the cellular and molecular factors involved in the epithelial–mesenchymal transition and extracellular matrix remodeling triggered by agents producing DIGO.

Gingival Enlargement Caused by Calcium Channel Blockers

Calcium channel blockers, a group of drugs widely used in the treatment of cardiovascular patients, although effective, often cause gingival enlargement, a side effect that is rarely recognized in clinical practice and is not given sufficient importance. Gingival enlargement caused by calcium channel blockers can be localized or generalized, mild or severe. It can negatively affect patients’ appearance, mastication, and speech, thus considerably reducing the quality of life of patients. Risk factors and pathogenesis of this side effect have been the subject of many studies but are still unknown, making this condition a major therapeutic challenge, especially if the cessation of the offending drug is not possible. This study aimed to review the etiology, potential risk factors, pathogenesis, clinical features, and therapy possibilities for gingival enlargement caused by calcium channel blockers.

Identifying the focuses of hereditary gingival fibromatosis with bioinformatics strategies

OBJECTIVE

The objective of this study was to detect the undiscovered bioinformatics information about hereditary gingival fibromatosis and find focuses from published datasets.

METHODS

Two published datasets containing gingival tissue expression profiles of HGF and healthy groups were collected from GEO database. GSE4250 was utilized for cardinality analysis, including the differentially expressed gene analysis, enrichment analyses, hierarchical clustering analysis, and protein-protein interaction network. Key genes were obtained from the protein interaction network plot. GSE58482 was utilized for validation.

RESULTS

Analysis of the expression profiling by array, there were 785 genes (380 upregulated genes, 405 downregulated genes) expressed differentially between HGF gingival tissue and healthy gingival tissue. KEGG and GO enrichment analyses obtained candidate pathways. Differentially expressed genes were associated with activated pathways like skin barrier pathway and cornified envelope pathway. Repressed pathways included ion homeostasis pathway, receptor ligand activity pathway, and cell population proliferation pathway. Key genes such as F2R, TGM7, and MMP13 were confirmed with differential expression by external validation.

CONCLUSION

By bioinformatics approaches, we found new discoveries including several pathways and key genes. These discoveries deserve attention and research in the future.

Refining the Mechanism of Drug-Influenced Gingival Enlargement and Its Management

Drug-influenced gingival enlargement (DIGE) or overgrowth manifests as abnormal enlargement of the gingiva due to an adverse effect of certain drug reactions in patients treated with anticonvulsants, immunosuppressants, or calcium channel blockers (CCBs). As the gingival enlargement became significant, it may interfere with the normal oral hygiene measures, aesthetics, as well as masticatory functions of the patients. The exact mechanism of how this undesirable condition develops is yet unknown, and complicated, with non-inflammatory and inflammatory pathways involved. This review illuminates these putative pathways of DIGE and highlights various treatment approaches based on existing research and current observations.

Biology of Drug-Induced Gingival Hyperplasia: In Vitro Study of the Effect of Nifedipine on Human Fibroblasts

Background: It has been proven that the antihypertensive agent nifedipine can cause gingival overgrowth as a side effect. The aim of this study was to analyze the effects of pharmacological treatment with nifedipine on human gingival fibroblasts activity, investigating the possible pathogenetic mechanisms that lead to the onset of gingival enlargement. Methods: The expression profile of 57 genes belonging to the “Extracellular Matrix and Adhesion Molecules” pathway, fibroblasts’ viability at different drug concentrations, and E-cadherin levels in treated fibroblasts were assessed using real-time Polymerase Chain Reaction, PrestoBlue™ cell viability test, and an enzyme-linked immunoassay (ELISA), respectively. Results: Metalloproteinase 24 and 8 (MMP24, MMP8) showed significant upregulation in treated cells with respect to the control group, and cell adhesion gene CDH1 (E-cadherin) levels were recorded as increased in treated fibroblasts using both real-time PCR and ELISA. Downregulation was observed for transmembrane receptors ITGA6 and ITGB4, the basement membrane constituent LAMA1 and LAMB1, and the extracellular matrix protease MMP11, MMP16, and MMP26. Conclusions: The obtained data suggested that the pathogenesis of nifedipine-induced gingival overgrowth is characterized by an excessive accumulation of collagen due to the inhibition of collagen intracellular and extracellular degradation pathways.

Gingival overgrowth induced by anticonvulsant drugs: A cross-sectional study on epileptic patients

OBJECTIVE

Our aim was to estimate the prevalence of gingival overgrowth (hyperplasia) and to determine whether active molecules affect the severity of overgrowth in a group of epileptic patients.

BACKGROUND

The effects of phenytoin on oral health have been explored in different studies, yet little information is available on other antiepileptic drugs.

METHODS

Data were collected from 213 subjects of both sexes, from 5 to 80 years. Patients taking the same antiepileptic therapy for at least 1 year and meeting the inclusion criteria of the study (n = 162) were subjected to measurement of gingival overgrowth according to the modified Harris and Ewalt classification and O'Leary's plaque control record (OLR). Descriptive statistics were calculated. Data were analyzed using Pearson's r correlation coefficient and chi-square test. Significance level was set at 5%.

RESULTS

The active drugs lamotrigine, oxcarbazepine, and phenobarbital were significantly associated with gingival overgrowth in 61%, 71%, and 53% of cases, respectively, and phenytoin, valproic acid, and carbamazepine in 50%, 44%, and 32% of cases, respectively.

CONCLUSION

Different antiepileptic molecules may be related to gingival overgrowth. In addition to phenytoin, also lamotrigine, oxcarbazepine, and phenobarbital were associated with increased prevalence of gingival overgrowth. In the management of epileptic patients, dentists should take into account different drugs as possible causes for gingival overgrowth and warn for possible alternatives.

Drug-Induced Gingival Overgrowth: A Pilot Study on the Effect of Diphenylhydantoin and Gabapentin on Human Gingival Fibroblasts

INTRODUCTION

The administration of several classes of drugs can lead to the onset of gingival overgrowth: anticonvulsants, immunosuppressants, and calcium channel blockers. Among the anticonvulsants, the main drug associated with gingival overgrowth is diphenylhydantoin.

MATERIALS AND METHODS

In this study, we compared the effects of diphenylhydantoin and gabapentin on 57 genes belonging to the "Extracellular Matrix and Adhesion Molecule" pathway, present in human fibroblasts of healthy volunteers.

RESULTS

Both molecules induce the same gene expression profile in fibroblasts as well as a significant upregulation of genes involved in extracellular matrix deposition like COL4A1, ITGA7, and LAMB3. The two treatments also induced a significant downregulation of genes involved in the expression of extracellular matrix metalloproteases like MMP11, MMP15, MMP16, MMP24, and transmembrane receptor ITGB4.

CONCLUSIONS

Data recorded in our study confirmed the hypothesis of a direct action of these drugs at the periodontium level, inducing an increase in matrix production, a reduction in its degradation, and consequently resulting in gingival hyperplasia.

Drug-Induced Gingival Overgrowth: The Effect of Cyclosporin A and Mycophenolate Mophetil on Human Gingival Fibroblasts

Drug-induced gingival overgrowth may occur after a chronic administration of three classes of systemic drugs: Anticonvulsants, immunosuppressants, and calcium channel blockers. This study aimed to investigate how cyclosporin A and mycophenolate mophetil (immunosuppressive drugs) could interfere with human gingival fibroblasts functions, leading to gingival enlargement. Human gingival fibroblasts derived from the tissue of a 60-year-old female were cultured in a DMEME medium. A stock solution with 1 mg/mL of mycophenolate and 1 mg/mL of cyclosporine were prepared and dissolved in a DMEM medium to prepare a serial dilution at the concentrations of 5000, 2000, 1000, 500, and 100 ng/mL, for both treatments. Cell viability was measured using the PrestoBlue™ Reagent Protocol. Quantitative real-time RT-PCR was performed in order to analyze the expression of 57 genes coding for gingival fibroblasts "Extracellular Matrix and Adhesion Molecules". Mycophenolate and cyclosporine had no effect on fibroblast cell viability at 1000 ng/mL. Both the treatments showed similar effects on the expression profiling of treated cells: Downregulation of most extracellular matrix metalloproteases genes (MMP8, MMP11, MMP15, MMP16, MMP24) was assessed, while CDH1, ITGA2, ITGA7, LAMB3, MMP12, and MMP13 were recorded to be upregulated in fibroblasts treated with immunosuppressive drugs. It has been demonstrated that gingival overgrowth can be caused by the chronic administration of cyclosporin A and mycophenolate mophetil. However, given the contrasting data of literature, further investigations are needed, making clear the possible effects of immunosuppressive drugs on fibroblasts.

SPOCK1 is a novel inducer of epithelial to mesenchymal transition in drug-induced gingival overgrowth

Few studies have investigated the role of extracellular-matrix proteoglycans in the pathogenesis of drug-induced gingival overgrowth (DIGO). SPOCK1 is an extracellular proteoglycan that induces epithelial to mesenchymal transition (EMT) in several cancer cell lines and exhibits protease-inhibitory activity. However, the role of SPOCK1 in non-cancerous diseases such as DIGO has not been well-addressed. We demonstrated that the expression of SPOCK1, TGF-β1, and MMP-9 in calcium channel blocker-induced gingival overgrowth is higher than that in non-overgrowth tissues. Transgenic mice overexpressing Spock1 developed obvious gingival-overgrowth and fibrosis phenotypes, and positively correlated with EMT-like changes. Furthermore, in vitro data indicated a tri-directional interaction between SPOCK1, TGF-β1, and MMP-9 that led to gingival overgrowth. Our study shows that SPOCK1 up-regulation in a noncancerous disease and SPOCK1-induced EMT in gingival overgrowth occurs via cooperation and crosstalk between several potential signaling pathways. Therefore, SPOCK1 is a novel therapeutic target for gingival overgrowth and its expression is a potential risk of EMT induction in cancerous lesions.

Nizam MN, Alshammari A. An Update on the Mechanisms of Phenytoin Induced Gingival Overgrowth

Background:

Phenytoin induced gingival overgrowth, a side effect with multifactorial aetiology, is characterized by an increase in the volume of extracellular tissues, particularly collagenous components, with varying degrees of inflammation.

Objective:

The aim of this paper is to review the available literature regarding the pathophysiological mechanisms of phenytoin induced gingival overgrowth.

Methods:

A thorough literature search of the PubMed/ Embase/ Web of science/ Cochrane central database was conducted to identify the mechanisms involved in the process of phenytoin-induced gingival overgrowth using the following keywords: Phenytoin; Anticonvulsant; Gingival Overgrowth; Gingival Enlargement, Gingival Hyperplasia; Drug Induced Gingival Enlargement; Drug Induced Gingival Overgrowth

Results:

According to the available evidence, several mechanisms have been proposed addressing the pathophysiological mechanism of phenytoin induced gingival overgrowth both at a cellular and molecular level. Evidence suggests that the inflammatory changes in the gingival tissues orchestrate the interaction between phenytoin and fibroblasts particularly resulting in an increase in the extracellular matrix content.

Conclusion:

However, the mechanism of production of inflammatory mediators is not fully understood. This, together with the high prevalence of Phenytoin induced gingival overgrowth, warrants further research in this area in order to develop treatment and preventive strategies for the management of this condition.

Periodontal Management of Cyclosporin A-Induced Gingival Overgrowth: A Nonsurgical Approach

Gingival overgrowth is a major and frequent unwanted effect accompanying the chronic usage of antihypertensive, anticonvulsant, and immunosuppressant drugs. The expression and the severity of this tissue-specific condition are influenced by a variety of factors, mainly drug and periodontal variables. Such increased volume of gingiva may compromise normal oral functions, aesthetics in addition to the patients' ability to practice optimal oral hygiene. The management of gingival overgrowth includes nonsurgical approach, surgical approach, or both of them for severe cases of gingival overgrowth as well as drug withdrawal. This case report illustrates a successful nonsurgical management of a 21-year-old patient with cyclosporin A-induced gingival overgrowth who experienced a total regression of the gingival enlargement without any surgical procedure or drug substitution. And it highlights therefore the key role of supportive periodontal therapy in maintaining good and stable outcomes over 2 years of follow-up.

Topical application of phenytoin or nifedipine-loaded PLGA microspheres promotes periodontal regeneration in vivo

OBJECTIVES

Gingival recession and alveolar bone loss are common manifestations of periodontitis. Periodontal regeneration is the ideal strategy for rehabilitating periodontal tissue defects and preventing tooth loss. The present study examined whether localized, topical application of gingival overgrowth-inducing drugs, phenytoin, nifedipine or cyclosporine, induces periodontal regeneration.

METHODS

Polylactic-co-glycolic acid (PLGA) was used as the carrier for preparation of phenytoin, nifedipine or cyclosporine-loaded PLGA microspheres, using an oil-in-water emulsification technique. The drug-loaded microspheres were delivered to periodontal defects created on alveolar ridges mesial to the first maxillary molars of Sprague-Dawley rats. After eight weeks, the operation area in each rat, including the maxillary molars and periodontal tissues, was harvested and evaluated by micro-computed tomography, histochemical and immunohistochemical analyses.

RESULTS

Physical parameters representative of periodontal regeneration, including the length of new alveolar bone (p < 0.01) and the area of new alveolar bone (p < 0.01) were significantly improved in the phenytoin group. Compared to other groups, the phenytoin group demonstrated increased expression of COL-1, VEGF-A, osteoblast and osteoclast markers (BMP-2, TGF-β1, OCN and TRAP staining), as well as decreased expression of MMP-8.

CONCLUSIONS

Results of the present study provided new evidence that localized, controlled release of phenytoin confers therapeutic benefits toward gingival recession and alveolar bone loss. Phenytoin appears to be a promising drug that promotes periodontal regeneration.

The Periodontium as a Potential Cause of Orofacial Pain: A Comprehensive Review

Introduction:

Orofacial pain of periodontal origin has a wide range of causes, and its high prevalence and negative effect on patients' quality of life make intervention mandatory. This review provides a periodontological overview of the field of orofacial pain, focusing on the entities which involve the periodontal tissues and may be the cause of this pain or discomfort.

Methods:

The study comprised a literature search of these pathologies conducted in the MEDLINE/PubMed Database. Acute infectious entities such as gingival and periodontal abscesses are emergencies that require a rapid response. Periodontitis associated with endodontic processes, necrotizing periodontal disorders, desquamative gingivitis, gingival recession, and mucogingival herpetic lesions, cause mild to severe pain due to tissue destruction and loss. Other lesions that lead to periodontal discomfort include gingival enlargement and periodontal ligament strains associated with occlusal trauma, parafunctional habit and the impaction of food or foreign bodies.

Conclusion:

A range of therapeutic, pharmacological and surgical alternatives are available for the management of these injuries. However, the wide variety of causes of orofacial pain or periodontal discomfort may confuse the clinician during diagnosis and may lead to the wrong choice of treatment.