TL;DR

Key Facts

What Is Gingivitis?

Gingivitis is inflammation of the gingiva — the soft tissue that surrounds and supports the teeth — without extension of the inflammatory process into the underlying periodontal ligament, alveolar bone, or root cementum. It is the most common form of periodontal disease worldwide, affecting the majority of dentate adults and nearly all children and adolescents at some point. The term “gingivitis” encompasses a spectrum of conditions ranging from mild localised erythema around a single tooth to severe generalised gingival swelling, spontaneous haemorrhage, and tissue necrosis in the most acute forms.

The word itself derives from the Latin gingiva (gum) and the Greek suffix -itis (inflammation). Its defining characteristic — and most clinically important feature — is reversibility. Unlike periodontitis, where bone and connective tissue attachment are permanently lost, gingivitis does not result in structural destruction of the supporting periodontium. Complete resolution of gingivitis, with return of gingival tissues to clinical health, is achievable through effective plaque removal alone — no surgery, no antibiotics, no permanent structural deficit. This makes gingivitis the most preventable and most treatable of all periodontal diseases, and its management one of the most important public health interventions in dentistry.

However, gingivitis carries serious implications beyond its local gingival manifestation. It is the obligatory precursor to periodontitis: in susceptible individuals, unresolved gingivitis can transition to periodontitis when the inflammatory response extends apically beyond the gingival margin into the supporting structures. Additionally, gingival inflammation creates a chronically disrupted mucosal barrier that may contribute to systemic inflammatory burden — the same pathways that link periodontitis to cardiovascular disease, diabetes, and adverse pregnancy outcomes begin at the gingivitis stage. Understanding, diagnosing, and treating gingivitis is therefore not merely a matter of managing red, bleeding gums — it is the first line of defence against a condition with potentially systemic consequences.

Why It Matters (Clinical + Exam Context)

Gingivitis is among the most heavily tested topics across all dental board examinations because it bridges basic science (microbiology, immunology, histopathology) with clinical practice (diagnosis, treatment planning, oral health education) and systemic medicine (systemic modifying factors, drug interactions). Boards test the 2017 classification, the histopathological stages, the distinction from periodontitis, NUG diagnosis and management, DIGO drug categories and mechanisms, and the evidence base for treatment interventions.

Clinical Relevance

• Gingivitis management is the entry point to all periodontal care: No periodontal surgical procedure, regenerative therapy, or implant placement should be performed in the presence of active gingivitis. The reason is physiological: surgery on inflamed tissue carries greater haemorrhage risk, reduced wound healing, and increased infection risk. More fundamentally, a patient who cannot achieve gingival health through improved home care and professional debridement has demonstrated that they do not yet have the plaque control skills required to maintain surgical outcomes. In clinical practice, Step 1 of all periodontal therapy — regardless of disease severity — is elimination of gingivitis through supragingival scaling, oral hygiene instruction, and re-evaluation. Surgical intervention is considered only when health cannot be achieved non-surgically or residual pocketing persists after full cause-related therapy.
• Systemic modification is the key to understanding the full spectrum of gingival disease: A patient with excellent oral hygiene who presents with generalised BOP, erythematous marginal gingivitis, and spontaneous gingival bleeding is not presenting with simple plaque-induced gingivitis. The disproportionate severity relative to plaque levels is the clinical signal that a systemic modifying factor — pregnancy, leukaemia, vitamin C deficiency, medication — may be driving the presentation. Recognising this pattern and screening for systemic modifying factors is essential: in rare cases, what appears to be gingivitis is the presenting sign of a life-threatening haematological malignancy (leukaemia) or a potentially serious nutritional deficiency.
• Bleeding on probing requires documentation and a clinical response: BOP recorded at a dental appointment is not a notation for the patient to brush harder — it is a clinical finding that demands a structured response: oral hygiene assessment (O’Leary plaque score), OHI provision, professional debridement, and recall scheduling appropriate to BOP extent. Full-mouth BOP >30% is the clinical threshold for generalised gingivitis. The goal of treatment is full-mouth BOP <10%, at which point gingival health has been achieved. Failing to document BOP, failing to respond to elevated BOP, and failing to track BOP over treatment represents a departure from the standard of care that is visible and reviewable in a medico-legal audit of clinical records.
• NUG is a dental emergency that requires immediate treatment and systemic screening: Necrotizing ulcerative gingivitis (NUG) is acutely painful, spreads rapidly if untreated, and is associated with HIV/AIDS and other immunocompromising conditions. The presentation is sufficiently distinctive — punched-out necrotic papillae, fetid halitosis, spontaneous bleeding — that it should never be missed. Delayed treatment allows progression to necrotizing periodontitis (with bone loss) and, in severely immunocompromised patients, necrotizing stomatitis (with extensive soft tissue destruction). Any patient presenting with NUG who lacks a clear predisposing factor (acute stress, recent viral illness, smoking) should be screened for HIV and haematological disorders.
• Drug-induced gingival overgrowth must be identified early and managed proactively: DIGO from phenytoin, ciclosporin, or calcium channel blockers can significantly impair oral hygiene, progress to extensive gingival masking of tooth crowns, and create a cycle of worsening plaque retention and inflammation. Early identification — at the appointment when a patient begins one of these medications — allows preventive intervention: intensive OHI and professional cleaning to minimise plaque co-factor contribution before overgrowth becomes established. Late identification — when overgrowth is already extensive — typically requires surgical intervention. Drug substitution (e.g., replacing nifedipine with amlodipine, which carries lower DIGO risk; or replacing phenytoin with an alternative antiepileptic) should be discussed with the prescribing physician, though decisions about systemic medication always rest with the medically responsible clinician.

Classification of Gingival Diseases

The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions (jointly organised by the European Federation of Periodontology and the American Academy of Periodontology) replaced the 1999 International Workshop Classification and established the current framework for classifying gingival health and disease. Gingival conditions are divided into two primary categories: plaque-induced gingivitis (accounting for the large majority of cases), and non-plaque-induced gingival conditions (a heterogeneous group of conditions sharing the gingiva as the primary site of manifestation but driven by factors other than dental plaque).

Plaque-Induced Gingivitis (2017 Classification)

Plaque-induced gingivitis is defined as inflammation of the gingiva that is directly associated with dental plaque biofilm and that resolves completely when plaque is adequately removed. The 2017 classification stratifies plaque-induced gingivitis by the status of the underlying periodontium:

Plaque-induced gingivitis is further classified by extent: localised (affecting fewer than 30% of teeth) or generalised (affecting 30% or more of teeth); and by the presence or absence of local risk factors (e.g., subgingival calculus, overhanging restorations, orthodontic appliances that impair plaque removal) and systemic modifying factors (see Section 5 below). The identification of modifying factors is essential because it explains cases where gingivitis severity is disproportionate to the plaque burden observed — and points toward additional management interventions beyond standard scaling and OHI.

Non-Plaque-Induced Gingival Conditions

Non-plaque-induced gingival conditions encompass a diverse group of diseases that manifest in the gingival tissues but are driven by factors other than — or in addition to — dental plaque. They are classified by aetiology and share the common feature that plaque control alone is insufficient for resolution; the underlying cause must also be identified and managed. The major categories are:

Necrotizing Ulcerative Gingivitis (NUG)

Necrotizing ulcerative gingivitis is an acute, destructive condition that occupies a distinct position within the 2017 classification as one of the necrotizing periodontal diseases (alongside necrotizing periodontitis and necrotizing stomatitis). It is characterised by necrosis and ulceration of the gingival tissues, particularly at the interdental papillae, and is associated with a specific polymicrobial infection involving fusiform bacteria and spirochaetes.

The causative organisms — sometimes still called Vincent’s organisms after the French physician Jean-Baptiste Vincent who described the condition in soldiers during the First World War — are a synergistic polymicrobial combination of Fusobacterium nucleatum (a Gram-negative anaerobic fusiform rod), Treponema species (oral spirochaetes), and Prevotella intermedia. These organisms are present in healthy gingival sulci at low levels but proliferate dramatically in the immunocompromised or stressed host.

Predisposing factors are essential to identify because they explain why NUG occurs and guide management: psychological stress (classically “trench mouth” in soldiers — hence historical nomenclature; exam stress in students; bereavement); smoking (nicotine and carbon monoxide impair gingival blood flow and neutrophil function); immunocompromise — particularly HIV/AIDS (NUG was a sentinel condition for AIDS before highly active antiretroviral therapy; recurrent or severe NUG in an otherwise healthy young adult should prompt HIV testing); haematological malignancy; severe malnutrition (particularly common in children in sub-Saharan Africa — cancrum oris/noma is the devastating extreme of necrotizing stomatitis in the severely malnourished immunocompromised child).

Distinguishing NUG from acute herpetic gingivostomatitis (AHGS) is a critical clinical skill because the treatments are different and prescribing metronidazole for AHGS will not help:

Pathology and Microbiology of Gingivitis

Histopathological Stages (Page and Schroeder, 1976)

The histopathological progression of gingivitis was systematically described by Page and Schroeder in 1976 in their landmark study on the evolution of inflammatory periodontal disease. Four stages of lesion development describe the tissue response from initial plaque accumulation to established clinical gingivitis — and, if disease progresses, to the advanced lesion of periodontitis. These stages are heavily tested on boards because they link microbiology to immunopathology to clinical signs.

Plaque Biofilm — Aetiology and Microbiology

Dental plaque is the aetiological agent of gingivitis. It is not a random accumulation of bacteria on the tooth surface — it is a highly organised, structured, multispecies biofilm with distinct architecture, fluid channels, communication systems (quorum sensing), and a protective extracellular matrix that confers significant resistance to antimicrobial agents. Understanding plaque biofilm biology explains why mechanical disruption (brushing, interdental cleaning) is the cornerstone of gingivitis treatment and why antimicrobial mouthwash alone is insufficient.

Biofilm formation follows a predictable sequence: the acquired salivary pellicle (a thin film of glycoproteins and lipids that adsorb to the cleaned enamel surface within minutes) provides a substrate for early bacterial colonisation. Early colonisers — predominantly Gram-positive facultative anaerobes such as Streptococcus sanguinis, S. gordonii, and Actinomyces species — attach to the pellicle and establish the foundation of the biofilm. Bridging organisms — particularly Fusobacterium nucleatum — then co-aggregate with the early colonisers and with each other, forming the structural backbone that permits late coloniser attachment. Late colonisers — the Gram-negative obligate anaerobes including Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola (the red complex organisms associated with periodontitis) — colonise the deeper, oxygen-poor regions of the mature biofilm. In gingivitis, the microflora transitions from the health-associated Gram-positive community toward an enrichment of Gram-negative anaerobes, particularly Prevotella intermedia and Fusobacterium nucleatum.

Calculus (tartar) is mineralised dental plaque — supragingival calculus mineralises from calcium and phosphate ions in saliva; subgingival calculus from ions in gingival crevicular fluid. Calculus is not inherently pathogenic itself — the bacterial cell walls within mineralised calculus are no longer viable. However, calculus is clinically important because its rough, porous surface provides an ideal substrate for further viable plaque retention and is physically impossible to remove by patient home care alone. Calculus therefore perpetuates gingivitis by preventing the plaque-free surfaces required for gingival health — which is why professional scaling to remove calculus is essential in the treatment of chronic gingivitis.

Systemic Modifying Factors

Systemic modifying factors are host conditions that amplify the gingival inflammatory response to plaque beyond what would be predicted from the plaque levels alone. Their identification changes the diagnosis, explains disproportionate clinical severity, and may change the management plan. The most clinically important systemic modifying factors in gingivitis are:

• Puberty-associated gingivitis: Elevated sex hormone levels during puberty increase vascular permeability and gingival inflammatory response; clinical gingivitis that is disproportionate to plaque levels. Particularly severe around partially erupted teeth and in the presence of orthodontic appliances. Generally resolves post-puberty if plaque control is improved; OHI and professional cleaning are the primary interventions.
• Pregnancy-associated gingivitis: Affects the majority of pregnant women, particularly in the second and third trimesters when progesterone levels are highest. Characterised by generalised erythema, oedema, and BOP disproportionate to plaque levels; driven primarily by Prevotella intermedia proliferation (see callout above). Periodontal treatment — scaling and OHI — is safe throughout pregnancy and is particularly recommended in the second trimester. The pregnancy epulis (pyogenic granuloma of pregnancy) is a vascular reactive overgrowth that typically occurs at an interdental papilla, is soft, red, and bleeds readily, and may regress post-partum — but persisting lesions require surgical excision.
• Diabetes mellitus–associated gingivitis: Poorly controlled DM (elevated HbA1c) amplifies gingival inflammation through multiple mechanisms: impaired neutrophil function (reduced chemotaxis, phagocytosis, and killing capacity); accumulation of advanced glycation end-products (AGEs) in gingival tissues; altered collagen metabolism; increased pro-inflammatory cytokine production. The gingivitis associated with poorly controlled DM is more severe, more generalised, and less responsive to standard treatment than in the non-diabetic patient with equivalent plaque levels. Glycaemic control is a treatment objective — periodontal treatment has been shown to modestly improve HbA1c in diabetic patients, reflecting the bidirectional relationship between periodontal inflammation and systemic glycaemic control.
• Leukaemia-associated gingival changes: In acute leukaemia (particularly acute myelogenous leukaemia, AML; also acute lymphoblastic leukaemia, ALL), malignant leukocytes can infiltrate the gingival tissues directly, producing severe generalised gingival swelling, dark erythema, spontaneous haemorrhage, and tissue necrosis. Thrombocytopenia (from marrow replacement or chemotherapy) contributes to the haemorrhagic tendency. Gingival changes are sometimes the presenting sign of previously undiagnosed leukaemia — a patient with severe, disproportionate gingival swelling and spontaneous bleeding without an obvious cause should have a full blood count requested urgently. Treatment of gingival changes is supportive (gentle debridement, chlorhexidine) until haematological management is instituted.
• Vitamin C deficiency (scurvy): Ascorbic acid (Vitamin C) is an essential cofactor for prolyl hydroxylase — the enzyme that hydroxylates proline and lysine residues during collagen synthesis. Deficiency results in production of structurally abnormal collagen that is mechanically weak and not effectively cross-linked. In the gingiva, this manifests as haemorrhagic, friable, swollen, and easily traumatised gingival tissues — scorbutic gingivitis. The gingiva appears spongy, dark red to purple, and bleeds with the slightest touch. Teeth may become mobile as PDL collagen degrades. Associated with vitamin C deficiency in elderly patients, alcoholics, patients with extreme dietary restriction, or populations with inadequate fresh fruit and vegetable access. Treatment is Vitamin C supplementation (500 mg/day) — gingival improvement occurs within days to weeks of correcting the nutritional deficiency.

Drug-Induced Gingival Overgrowth (DIGO)

Drug-induced gingival overgrowth (also called drug-influenced gingival enlargement — DIGE — or, historically, gingival hyperplasia/hypertrophy) is a well-characterised adverse effect of three drug categories: antiepileptics, immunosuppressants, and calcium channel blockers. It occurs in a proportion of patients taking these drugs — the incidence varies but is approximately 50% for phenytoin, 30% for ciclosporin, and 10–15% for nifedipine in adults. The severity is critically modulated by plaque levels — poor plaque control significantly worsens overgrowth extent and distribution.

The mechanism of DIGO is not fully understood but centres on altered fibroblast behaviour: affected drugs impair calcium channel function in gingival fibroblasts, leading to reduced collagen phagocytosis (less collagen degradation), increased fibroblast proliferation, and net accumulation of extracellular collagen matrix. A subpopulation of gingival fibroblasts appears to be genetically predisposed to this response — explaining why not all patients on these drugs develop overgrowth. Inflammation (driven by plaque) acts as a co-factor that amplifies fibroblast activation and accelerates overgrowth progression. This co-factor relationship is clinically exploitable: meticulous plaque control from the time the drug is started can significantly reduce the degree of overgrowth that develops, even if the drug cannot be changed.

Clinical Considerations

• Full-mouth BOP score as a treatment target: Treatment of gingivitis should be monitored by serial full-mouth BOP percentage, not by visual assessment alone. Erythema can persist transiently after scaling as the tissue remodels, but BOP reduction is a more objective and earlier indicator of treatment response. The BSP and AAP define gingival health as full-mouth BOP <10%. A post-treatment BOP of >30% at re-evaluation (6–8 weeks after scaling and OHI) indicates inadequate treatment response — which should prompt reassessment of oral hygiene technique, identification of missed calculus or subgingival deposits, and review of systemic modifying factors. Continued high BOP despite adequate treatment is an indication for comprehensive periodontal assessment to exclude periodontitis.
• Interdental cleaning is non-negotiable: Toothbrushing alone — however effective the technique — cannot access the interproximal surfaces where approximately 40% of the tooth surface resides and where plaque accumulation most commonly initiates interdental gingivitis and caries. Evidence consistently shows that interdental brushes are more effective than floss for most adults for both plaque removal and gingivitis reduction at sites with available embrasure space. Floss remains the recommendation for tight contact areas (particularly lower anterior teeth). The clinician’s role is to identify the appropriate interdental cleaning tool for each site (interdental brush size selection) and to verify correct technique at each appointment — not simply to advise “floss” generically.
• Chlorhexidine is a short-term adjunct, not a long-term substitute for mechanical plaque control: Chlorhexidine gluconate 0.2% (or 0.12% in the US formulation) is the most effective chemical adjunct to mechanical plaque control. Its bactericidal action and prolonged substantivity (8–12 hours of residual antimicrobial activity on mucosal surfaces) make it valuable for managing NUG, peri-surgical antisepsis, and acute gingivitis flares. However, long-term daily use is inappropriate for the management of chronic gingivitis because: (a) it causes significant brown staining of teeth, tongue, and restorations; (b) it alters taste perception; (c) it promotes calculus formation; (d) it does not address the root cause of gingivitis (inadequate mechanical plaque removal). Prescribe chlorhexidine for defined indications (NUG, post-surgical, immunocompromised patients with genuine difficulty brushing) for defined periods (weeks, not months), and document the indication and intended duration in the clinical record.
• Electric toothbrushes with oscillating-rotating action have the strongest evidence for gingivitis reduction: A 2019 Cochrane systematic review (Yaacob et al.) concluded that powered toothbrushes with oscillating-rotating action (e.g., Oral-B) produce a statistically significant and clinically meaningful reduction in gingivitis compared with manual brushing — approximately 17% reduction in the Gingival Index. This evidence is specific to the oscillating-rotating action; sonic brushes showed a smaller, less consistent advantage. For patients with physical limitations (arthritis, reduced dexterity, disability) or those who consistently fail to achieve plaque control with manual brushing, powered toothbrush prescription is an evidence-based clinical recommendation, not a lifestyle preference.
• Periodontal recall interval should reflect actual disease risk and clinical status — not a standard six-month interval for all patients: NICE guidance (CG19, 2004; updated 2012) and the BSP risk-stratified recall framework both specify that recall intervals should be individualised. A patient with Code 1 BPE, low caries risk, and good plaque control can appropriately be recalled at 12–24 months. A patient with generalised Code 3 BPE, high BOP, multiple systemic modifying factors, and a smoking history requires a 3-month supportive periodontal therapy recall. Prescribing identical six-month intervals for all adult patients is not evidence-based — it under-manages high-risk patients and over-services low-risk patients, wasting clinical capacity.
• Inform patients that bleeding gums require dental attendance — not avoidance of brushing: The most common and most damaging public misconception about gingivitis is that bleeding gums mean the patient is “brushing too hard” and should brush less vigorously or avoid the bleeding area. This misconception — sometimes reinforced by clinicians who have not explained the cause of BOP — leads patients to reduce mechanical plaque removal at exactly the sites that most require it, allowing established gingivitis to worsen. Patient education must explicitly address this: “Your gums bleed because they are inflamed from bacterial buildup. The solution is to brush more effectively and more consistently at the bleeding sites — not less. If you brush correctly twice a day and clean between your teeth, the bleeding should reduce significantly within two weeks.” Documenting that this education was given is good practice and supports medicolegal defence if compliance-related periodontal damage is later alleged.

Common Mistakes & Misconceptions

• Misconception: “Bleeding gums are normal, especially when brushing.”
  Correction: Healthy gingiva does not bleed on probing or on toothbrushing. Bleeding is a reliable clinical sign of gingival inflammation — specifically, the presence of a vascular, inflamed, and ulcerated sulcular epithelium. The statement “my gums always bleed when I brush” is a description of uncontrolled gingivitis, not a normal finding. The public perception that gingival bleeding during brushing is caused by brushing too hard is almost universally incorrect — in the vast majority of cases, it reflects inadequate plaque control at the gingival margin. BOP is the most sensitive, objective, and reproducible clinical indicator of gingival inflammation available, and its presence always warrants a clinical response.
• Misconception: “All gingivitis will eventually progress to periodontitis if left untreated.”
  Correction: The transition from gingivitis to periodontitis is not inevitable and depends critically on host susceptibility. Many individuals maintain stable, long-standing gingivitis for years or decades without ever developing clinical attachment loss — their immune-inflammatory response, while producing gingival inflammation, never extends apically to destroy the supporting periodontium. Conversely, some highly susceptible individuals progress rapidly from gingivitis to severe generalised periodontitis. The key insight from the Page and Schroeder model and from longitudinal epidemiological data is that the “advanced lesion” of periodontitis requires a permissive host environment — genetic susceptibility, specific microbial virulence, systemic modifying factors — not merely the passage of time. However, it is equally important to communicate that while not inevitable, the risk is real in susceptible individuals — and that resolving gingivitis eliminates the risk of it progressing.
• Misconception: “Pregnancy causes gingivitis independently.”
  Correction: Pregnancy does not independently cause gingivitis — it amplifies the gingival inflammatory response to pre-existing plaque. A pregnant patient with no plaque and healthy gingival tissues does not develop pregnancy gingivitis. The mechanism is the ability of Prevotella intermedia to use oestrogen and progesterone as growth factors, leading to its disproportionate proliferation in the subgingival plaque of pregnant women. This shifts the microbial composition toward a more pathogenic flora without any change in total plaque levels. The clinical implication is that pregnancy gingivitis is preventable through excellent plaque control — the conversation with a pregnant patient should be: “Your changing hormones make your gums more sensitive to plaque. It’s more important than ever during pregnancy to brush effectively twice a day and clean between your teeth, and to attend for a professional clean in the second trimester.”
• Misconception: “NUG and acute herpetic gingivostomatitis (AHGS) present similarly and can be treated the same way.”
  Correction: NUG and AHGS are easily confused but are entirely different conditions — bacterial versus viral — with different management. NUG is bacterial (Fusobacterium + Treponema) and is treated with debridement + metronidazole; AHGS is caused by primary HSV-1 infection and is treated supportively (hydration, analgesia) with aciclovir reserved for severe or immunocompromised cases. The key distinguishing features are lesion location (NUG: confined to interdental papillae with characteristic punched-out craters; AHGS: vesicles and ulcers diffusely throughout the entire oral mucosa), patient age (NUG: adults in stress/immunocompromise; AHGS: predominantly children 1–6 years for primary infection), and systemic signs (AHGS: high fever, cervical lymphadenopathy; NUG: halitosis, low-grade or no fever). Prescribing metronidazole for AHGS is ineffective against HSV; prescribing aciclovir alone for NUG misses the bacterial component. Accurate diagnosis determines treatment.
• Misconception: “Using mouthwash daily is sufficient to treat and prevent gingivitis.”
  Correction: Mouthwash — including chlorhexidine, the most effective available agent — is an adjunct to mechanical plaque removal, not a substitute for it. Established plaque biofilm has a structured extracellular matrix that is highly resistant to antimicrobial penetration; the bacteria in the deeper layers of a mature biofilm are essentially shielded from chemical agents at the concentrations achievable in a mouthrinse. Mechanical disruption of the biofilm (by brushing and interdental cleaning) is required to expose and physically remove the bacteria. Antimicrobial rinses can suppress planktonic bacteria and early biofilm formation but cannot physically disrupt established plaque. The management of gingivitis requires daily mechanical plaque removal twice daily as the absolute foundation — mouthwash is an adjunct for specific indications, not a standalone treatment strategy.

Related Topics

Gingivitis sits at the intersection of preventive dentistry, periodontics, and systemic medicine — understanding it thoroughly enables better management at every level of periodontal care.

References & Sources

1. Chapple ILC, Mealey BL, et al. (2018). Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. Journal of Periodontology, 89(S1):S74–S84.
2. Page RC, Schroeder HE (1976). Pathogenesis of inflammatory periodontal disease: A summary of current work. Laboratory Investigation, 34(3):235–249. [Original description of the four histopathological stages of gingivitis/periodontitis]
3. Löe H, Theilade E, Jensen SB (1965). Experimental gingivitis in man. Journal of Periodontology, 36(3):177–187. [Landmark experimental study demonstrating plaque as the aetiological agent of gingivitis — complete reversal on plaque removal]
4. British Society of Periodontology (2019). BSP Implementation of the 2017 Classification of Periodontal Diseases — Good Practice Guideline. BSP.
5. Yaacob M, et al. (2014). Powered versus manual toothbrushing for oral health. Cochrane Database of Systematic Reviews, 6:CD002281. [Oscillating-rotating powered toothbrushes superior to manual for gingivitis reduction]
6. Mariotti A (1999). Dental plaque-induced gingival diseases. Annals of Periodontology, 4(1):7–19. [Classification of plaque-induced gingival diseases prior to the 2017 update]
7. Seymour RA, Ellis JS, Thomason JM (2000). Risk factors for drug-induced gingival overgrowth. Journal of Clinical Periodontology, 27(4):217–223.
8. Mealey BL, Moritz AJ (2003). Hormonal influences: Effects of diabetes mellitus and endogenous female sex hormones on the periodontium. Periodontology 2000, 32:59–81.

Summary

Gingivitis is reversible gingival inflammation caused by bacterial plaque biofilm, characterised by erythema, oedema, loss of stippling, and bleeding on probing — with no clinical attachment loss (CAL = 0 mm) and no radiographic bone loss. The 2017 World Workshop Classification divides gingival disease into plaque-induced gingivitis (on an intact, or reduced intact, or reduced non-periodontitis periodontium) and non-plaque-induced gingival conditions (specific infections, immune/inflammatory diseases, drug-induced lesions, reactive processes). Histopathologically, gingivitis progresses through the initial (PMN-dominated), early (T lymphocyte), and established (plasma cell) lesions — the established lesion is classic clinical gingivitis; the advanced lesion represents conversion to periodontitis. NUG is an acute necrotizing condition characterised by punched-out necrotic papillae, spontaneous bleeding, and fetid halitosis caused by Fusobacterium nucleatum and Treponema species; it must be distinguished from acute herpetic gingivostomatitis. Systemic modifying factors — pregnancy (Prevotella intermedia–amplified), poorly controlled diabetes, puberty, leukaemia, and vitamin C deficiency — amplify gingival inflammation disproportionate to plaque levels. Drug-induced gingival overgrowth (phenytoin, ciclosporin, nifedipine) is managed with intensive OHI, scaling, and surgical excision; drug substitution should be discussed with the prescribing physician. Treatment of all plaque-induced gingivitis is mechanical: effective daily brushing plus interdental cleaning, combined with professional supragingival scaling and OHI. Chlorhexidine 0.2% is a short-term adjunct for specific indications. Full-mouth BOP <10% is the clinical target of successful gingivitis treatment.

About the Author

Dr. Andries Smith

Founder, Dental Panda

Dr. Andries Smith founded Dental Panda in 2020. As an immigrant to the United States, he had to take the INBDE exam, even though he was practicing dentistry for over 10 years. This revealed an opportunity. Andries noticed that INBDE prep course companies were putting profit over students. With his expertise and experience in dentistry, he created free dental wiki resources for students and the general public to have access to.