NEET MDS Lessons
Periodontology
Aggressive periodontitis (AP) is a multifactorial, severe, and rapidly progressive form of periodontitis that primarily affects younger patients. It is characterized by a unique set of clinical and microbiological features that distinguish it from other forms of periodontal disease.
Key Characteristics
- Rapid Progression: AP is marked by a swift deterioration of periodontal tissues.
- Age Group: Primarily affects adolescents and young adults, but can occur at any age.
- Multifactorial Etiology: Involves a combination of microbiological, immunological, genetic, and environmental factors.
Other Findings
- Presence of Aggregatibacter actinomycetemcomitans (A.a.) in diseased sites.
- Abnormal host responses, including impaired phagocytosis and chemotaxis.
- Hyperresponsive macrophages leading to exaggerated inflammatory responses.
- The disease may exhibit self-arresting tendencies in some cases.
Classification
Aggressive periodontitis can be classified into two main types:
- Localized Aggressive Periodontitis (LAP): Typically affects the permanent molars and incisors, often with localized attachment loss.
- Generalized Aggressive Periodontitis (GAP): Involves more widespread periodontal tissue destruction.
Risk Factors
Microbiological Factors
- Aggregatibacter actinomycetemcomitans: A primary pathogen associated with LAP, producing a potent leukotoxin that kills neutrophils.
- Different strains of A.a. produce varying levels of leukotoxin, with highly toxic strains more prevalent in affected individuals.
Immunological Factors
- Human Leukocyte Antigens (HLAs): HLA-A9 and B-15 are candidate markers for aggressive periodontitis.
- Defective neutrophil function leads to impaired chemotaxis and phagocytosis.
- Hyper-responsive macrophage phenotype, characterized by elevated levels of PGE2 and IL-1β, may contribute to connective tissue breakdown and bone loss.
Genetic Factors
- Familial clustering of neutrophil abnormalities suggests a genetic predisposition.
- Genetic control of antibody responses to A.a., with variations in the ability to produce protective IgG2 antibodies.
Environmental Factors
- Smoking is a significant risk factor, with smokers experiencing more severe periodontal destruction compared to non-smokers.
Treatment Approaches
General Considerations
- Treatment strategies depend on the type and extent of periodontal destruction.
- GAP typically has a poorer prognosis compared to LAP, as it is less likely to enter spontaneous remission.
Conventional Periodontal Therapy
- Patient Education: Informing patients about the disease and its implications.
- Oral Hygiene Instructions: Reinforcing proper oral hygiene practices.
- Scaling and Root Planing: Removal of plaque and calculus to control local factors.
Surgical Resection Therapy
- Aimed at reducing or eliminating pocket depth.
- Contraindicated in cases of severe horizontal bone loss due to the risk of increased tooth mobility.
Regenerative Therapy
- Potential for regeneration is promising in AP cases.
- Techniques include open flap surgical debridement, root surface conditioning with tetracycline, and the use of allogenic bone grafts.
- Recent advances involve the use of enamel matrix proteins to promote cementum regeneration and new attachment.
Antimicrobial Therapy
- Often required as adjunctive treatment to eliminate A.a. from periodontal tissues.
- Tetracycline: Administered in various regimens to concentrate in periodontal tissues and inhibit A.a. growth.
- Combination Therapy: Metronidazole combined with amoxicillin has shown efficacy alongside periodontal therapy.
- Doxycycline: Used at a dose of 100 mg/day.
- Chlorhexidine (CHX): Irrigation and home rinsing to control bacterial load.
Host Modulation
- Involves the use of sub-antimicrobial dose doxycycline (SDD) to prevent periodontal attachment loss by modulating the activity of matrix metalloproteinases (MMPs), particularly collagenase and gelatinase.
Concentration Requirements
- Minimum Effective: 0.12%
- Optimum Concentration: 0.2%
- Duration: Typically used for 2-4 weeks
Side Effects
- Staining: Yellowish-brown stains on teeth and restorations
- Taste Alteration: Temporary metallic taste
- Soft Tissue Irritation: Rare but possible
Delivery Systems
- Chip Degradation: 7-10 days for chlorhexidine chips
- Sustained Release: Provides extended antimicrobial effect
🧬 Blood Disorders
- Polycythemia vera: Common cause of Budd – Chiari
- PNH: Rare cause of Budd – Chiari
- Thalassemia & Hemolytic anemia: Lead to unconjugated hyperbilirubinemia
- Anemia: Can cause high-output heart failure
- Hemophilia A: Deficiency of Factor VIII
- ITP vs TTP: ITP = isolated thrombocytopenia; TTP = microangiopathy
Assessing New Attachment in Periodontal Therapy
Assessing new attachment following periodontal therapy is crucial for evaluating treatment outcomes and understanding the healing process. However, various methods of assessment have limitations that must be considered.
1. Periodontal Probing
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Assessment Method: Periodontal probing is commonly used to measure probing depth and attachment levels before and after therapy.
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Limitations:
- Coronal Positioning of Probe Tip: After therapy, when the inflammatory lesion is resolved, the probe tip may stop coronal to the apical termination of the epithelium. This can lead to misleading interpretations of attachment gain.
- Infrabony Defects: Following treatment of infrabony defects, new bone may form so close to the tooth surface that the probe cannot penetrate. This can result in a false impression of improved attachment levels.
- Interpretation of Results: A gain in probing attachment level does not necessarily indicate a true gain of connective tissue attachment. Instead, it may reflect improved health of the surrounding tissues, which increases resistance to probe penetration.
2. Radiographic Analysis and Reentry Operations
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Assessment Method: Radiographic analysis involves comparing radiographs taken before and after therapy to evaluate changes in bone levels. Reentry operations allow for direct inspection of the treated area.
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Limitations:
- Bone Fill vs. New Attachment: While radiographs can provide evidence of new bone formation (bone fill), they do not document the formation of new root cementum or a new periodontal ligament. Therefore, radiographic evidence alone cannot confirm the establishment of new attachment.
3. Histologic Methods
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Assessment Method: Histologic analysis involves examining tissue samples under a microscope to assess the formation of new attachment, including new cementum and periodontal ligament.
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Advantages:
- Validity: Histologic methods are considered the only valid approach to assess the formation of new attachment accurately.
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Limitations:
- Pre-Therapy Assessment: Accurate assessment of the attachment level prior to therapy is essential for histologic analysis. If the initial attachment level cannot be determined with certainty, it may compromise the validity of the findings.
Electrosurgery
- Frequency: 1.5 – 7.5 million cycles/sec
Flap Incisions & Blades
- Internal bevel: #15 blade
- Crevicular: #12 blade
- Interdental: Orban's knife
Suturing Techniques
- Horizontal mattress: For diastema/wide spaces
- Anchor suture: For flap closure mesial/distal to tooth
Specific Procedures
- Modified Widman flap: Does not reduce pocket depth
- Apically displaced flap: Increases attached gingiva width
Osseous Surgery Sequence
- Osteoplasty: Vertical grooving, radicular blending
- Ostectomy: Flattening interproximal bone, gradualizing marginal bone
Bone Grafts
- FDBA: Osteoconductive
- DFDBA: Osteoinductive
- Hydroxyapatite: Ca:P ratio 1.67
- Beta – TCP: Ca:P ratio 1.5
Furcation Treatment
- Grade 2: "Cul – de – sac" defect
- Most common hemisection: Distobuccal root of maxillary 1st molar
Root Coverage Procedures
- Laterally displaced pedicle: Grupe & Warren technique
- Subepithelial connective tissue graft: Langer & Langer technique
- Papilla preservation flap: First choice for maxillary anterior (esthetics)
Healing Timeline
Scaling & Curettage
- Epithelialization: 2 – 7 days
- Immature collagen: 21 days
Gingivectomy
- Surface epithelialization: 5 – 14 days
- Complete repair: 1 month
Flap Surgery
- Epithelial attachment: 1 week
Naber’s Probe and Furcation Involvement
Furcation involvement is a critical aspect of periodontal disease that affects the prognosis of teeth with multiple roots. Naber’s probe is a specialized instrument designed to assess furcation areas, allowing clinicians to determine the extent of periodontal attachment loss and the condition of the furcation. This lecture will cover the use of Naber’s probe, the classification of furcation involvement, and the clinical significance of these classifications.
Naber’s Probe
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Description: Naber’s probe is a curved, blunt-ended instrument specifically designed for probing furcation areas. Its unique shape allows for horizontal probing, which is essential for accurately assessing the anatomy of multi-rooted teeth.
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Usage: The probe is inserted horizontally into the furcation area to evaluate the extent of periodontal involvement. The clinician can feel the anatomical fluting between the roots, which aids in determining the classification of furcation involvement.
Classification of Furcation Involvement
Furcation involvement is classified into four main classes using Naber’s probe:
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Class I:
- Description: The furcation can be probed to a depth of 3 mm.
- Clinical Findings: The probe can feel the anatomical fluting between the roots, but it cannot engage the roof of the furcation.
- Significance: Indicates early furcation involvement with minimal attachment loss.
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Class II:
- Description: The furcation can be probed to a depth greater than 3 mm, but not through and through.
- Clinical Findings: This class represents a range between Class I and Class III, where there is partial loss of attachment but not complete penetration through the furcation.
- Significance: Indicates moderate furcation involvement that may require intervention.
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Class III:
- Description: The furcation can be completely probed through and through.
- Clinical Findings: The probe passes from one furcation to the other, indicating significant loss of periodontal support.
- Significance: Represents advanced furcation involvement, often associated with a poor prognosis for the affected tooth.
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Class III+:
- Description: The probe can go halfway across the tooth.
- Clinical Findings: Similar to Class III, but with partial obstruction or remaining tissue.
- Significance: Indicates severe furcation involvement with a significant loss of attachment.
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Class IV:
- Description: Clinically, the examiner can see through the furcation.
- Clinical Findings: There is complete loss of tissue covering the furcation, making it visible upon examination.
- Significance: Indicates the most severe form of furcation involvement, often leading to tooth mobility and extraction.
Measurement Technique
- Measurement Reference: Measurements are taken from an imaginary tangent connecting the prominences of the root surfaces of both roots. This provides a consistent reference point for assessing the depth of furcation involvement.
Clinical Significance
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Prognosis: The classification of furcation involvement is crucial for determining the prognosis of multi-rooted teeth. Higher classes of furcation involvement generally indicate a poorer prognosis and may necessitate more aggressive treatment strategies.
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Treatment Planning: Understanding the extent of furcation involvement helps clinicians develop appropriate treatment plans, which may include scaling and root planing, surgical intervention, or extraction.
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Monitoring: Regular assessment of furcation involvement using Naber’s probe can help monitor disease progression and the effectiveness of periodontal therapy.
Gingival crevicular fluid is an inflammatory exudate found in the gingival sulcus. It plays a significant role in periodontal health and disease.
A. Characteristics of GCF
- Glucose Concentration: The glucose concentration in GCF is 3-4 times greater than that in serum, indicating increased metabolic activity in inflamed tissues.
- Protein Content: The total protein content of GCF is much less than that of serum, reflecting its role as an inflammatory exudate.
- Inflammatory Nature: GCF is present in clinically normal sulci due to the constant low-grade inflammation of the gingiva.
B. Drugs Excreted Through GCF
- Tetracyclines and Metronidazole: These antibiotics are known to be excreted through GCF, making them effective for localized periodontal therapy.
C. Collection Methods for GCF
GCF can be collected using various techniques, including:
- Absorbing Paper Strips/Blotter/Periopaper: These strips absorb fluid from the sulcus and are commonly used for GCF collection.
- Twisted Threads: Placing twisted threads around and into the sulcus can help collect GCF.
- Micropipettes: These can be used for precise collection of GCF in research settings.
- Intra-Crevicular Washings: Flushing the sulcus with a saline solution can help collect GCF for analysis.