14. Periodontology

Question 1

Perio classification

1. 10 classification categories

Answer 1

1. Health
   Plaque-induced gingivitis
   Non plaque-induced gingival diseases and conditions
   Periodontitis
   Necrotising periodontal diseases
   Periodontitis as a manifestation of systemic disease
   Systemic diseases or conditions affecting the periodontal tissues
   Periodontal abscesses
   Periodontal-endodontic lesions
   Mucogingival deformities and conditions

Question 2

Perio health

1. 2 categories and 2 features of each
2. 4 clinical features

Answer 2

1. Patients with an intact periodontium (no BoP, no attachment loss)
   Patients with a reduced and stable periodontium (BoP <10%, PPD <4mm)
2. Knife-edged, scalloped gingival margin, pink/pale, stippling, firm and flat, painless, no bleeding

Question 3

Gingivitis

1. 2 types
2. 3 clinical features
3. Difference between local and generalised
4. 3 local and 3 systemic modifying factors of type 1
5. 5 causes of type 2

Answer 3

1. Plaque induced or non-plaque induced
2. BPE 2 or less, no new bone loss, no loss of ID papilla, inflammation, loss of stippling, halitosis, BoP, red
3. Localised - BoP 10-30%; generalised - BoP >30%
4. Local - calculus, poor restoration margins, poor crown margins, hyposalivation
   Systemic - diabetes (hyperglycaemia), sex hormones (puberty, pregnancy), smoking, poor diet
5. Genetic/developmental (hereditary gingival fibromatosis), trauma, neoplasms, infections (PHG), inflammatory/immune conditions (desquamative gingivitis), reactive processes, endocrine, nutritional and metabolic disease

Question 4

Periodontitis

1. Give different types of extent
2. Describe staging
3. Describe grading
4. Describe status
5. Give 3 risk factors

Answer 4

1. Localised (<30%), generalised (>30%), molar incisor pattern
2. 1 - early/mild (<15%/2mm inter proximal bone loss)
   2 - moderate (bone loss <1/3 of root)
   3 - severe (bone loss 1/3-2/3 of root)
   4 - very severe (bone loss >2/3 of root)
3. A - mild - rate <0.5 (% bone loss/age)
   B - moderate - rate 0.5-1.0 (% bone loss/age)
   C - rapid - rate >1.0 (% bone loss/age)
4. Currently stable (BoP <10%, PPD <3mm)
   Currently in remission (BoP >10%, PPD <4mm with bleeding, PPD all <5mm)
   Currently unstable (pockets 5+mmmm; 4+mm pockets with BoP)
5. Diabetes, smoking, occlusal problems, local/systemic risk factors
6. Gingivitis + mobility, recession, root exposure, etc

Question 5

Necrotising periodontal diseases

1. 3 types and difference between them
2. 4 clinical features
3. 4 risk factors
4. Treatment

Answer 5

1. NG, NP (+ bone loss), NS (bone denudation extends beyond mucogingival junction)
2. Gingivitis, halitosis, loss of ID papilla (interproximal necrosis), bleeding, metallic taste, painful ulceration of ID papilla, pseudomembranous slough
3. Smoking, stress, immunocompromised, poor OH
4. OHI, smoking cessation
   Debridement (LA)
   MW (0.2% CHX or 6% H2O2)
   Antibiotics if systemic - metronidazole (400mg 3-5 days) or amoxicillin (500mg 3-5 days)

Question 6

Systemic implications

1. Cause of periodontitis as a manifestation of systemic disease
2. 3 systemic diseases associated with
3. 1 type of systemic diseases affecting periodontal tissues

Answer 6

1. Plaque biofilm induced inflammation
2. Down’s syndrome, ED syndrome, LAD, papillon lefevre, hypophosphatasia
3. SCC, langerhans cell histiocytosis

Question 7

Periodontal abscesses

1. Definition
2. 4 types
3. 4 clinical features
4. Treatment

Answer 7

1. Localised collection of dead and dying neutrophils
2. Gingival, periodontal, perio-endo, pericoronal
3. TTP (lateral), swelling, pain, bleeding, pus suppuration, deep pocket
4. OHI
   I+D (through pocket/socket), subgingival scaling (LA)
   CHX MW
   Antibiotics if appropriate

Question 8

Perio-endo lesions

1. 3 grades
2. 3 methods of perio-apical communications
3. 2 features of primary endo lesion
4. 2 features of primary perio lesion
5. 3 features of true combined lesion
6. Treatment

Answer 8

1. 1 - narrow deep perio pocket in 1 tooth surface
   2 - wide deep perio pocket in 1 tooth surface
   3 - deep perio pocket in 2+ tooth surfaces
2. Apical foramen, lateral canal, frugal canal, fractures, resorption, iatrogenic perforation
3. Localised perio disease, non-vital tooth
4. Generalised perio disease, usually non/minimally restored tooth
5. Generalised perio disease, unrestored tooth
6. RCT first, then perio treatment (NSPT then surgery if appropriate)

Question 9

Mucogingival deformities and conditions

1. Definition of recession
2. 3 types of recession
3. 4 reasons for recession

Answer 9

1. Lack of keratinised gingival/aberrant renal attachment. Displacement of gingival al soft tissue margin apical to ACJ resulting in root exposure
2. RT1 - recession with no loss of inter proximal attachment (inter proximal ACJ clinically undetectable both mesial and distal. Most of ID papilla remains)
   RT2 - gingival recession associated with loss of some inter proximal attachment (some ID papilla still remains; amount of attachment loss less than or equal to buccal attachment loss)
   RT3 - gingival recession associated with more loss of inter proximal attachment (no ID papilla remains; amount of inter proximal attachment loss greater than buccal attachment loss)
3. Successful HPT, vigorous brushing, traumatic incisal relationship, iatrogenic restorative treatment damage, foreign body trauma

Question 10

Abnormal occlusal forces

1. 4 causes of tooth mobility
2. Effect of abnormal occlusal forces on healthy periodontium
3. Effect of abnormal occlusal forces on healthy but reduced periodontium
4. Effect of abnormal occlusal forces on diseased periodontium
5. Response of healthy periodontium
6. 2 reasons to intervene in occlusal trauma

Answer 10

1. Alveolar bone loss, attachment loss, PDL atrophy (disuse), PDL widening, periodontal tissue disruption (due to inflammation)
2. Areas of intermittent pressure and tension, hyper mobile tooth, areas of widened PDL. Normal physiological response
3. Tooth effectively on alveolar bone fulcrum, hyper mobile tooth, in absence of plaque, gingival margin remains intact and perio disease will not restart
4. Zone of co-destruction - supra physiological occlusal forces widen PDL width at base of pocket, hyper mobile teeth; pathological disease (inflammation) causing CAL or excessive bone loss when combined
5. PDL widens until forces adequately dissipated, increase in tooth mobility. If demand reduced, PDL returns to normal. If demand too great, PDL continues to widen until forces adequately dissipated or tooth is lost (pathological failure of adaptation)
6. Symptomatic mobility, progressively increasing mobility

Question 11

Clinical Perio

1. BPE grades and recommended treatment options
2. Furcation grading
3. 4 factors affecting tooth mobility
4. 3 indications to intervene in tooth mobility
5. Tooth mobility grading
6. 3 treatment options for tooth mobility
7. 3 indications and 3 problems with 1 treatment option in Q6
8. 3 causes of tooth migration
9. 3 treatment options for tooth migration

Answer 11

1. 0 - no BoP, no PRFs, pockets <3.5mm. No Rx/OHI
   1 - pockets <3.5mm, BoP, no PRFs. OHI
   2 - BoP, PRFs, pockets <3.5mm. OHI, remove PRFs (scaling, correct defective margins)
   3 - pockets 3.5-5.5mm. OHI, RSD, PRF removal
   4 - pockets >5.5mm. OHI, RSD, PRF removal
   * - furcation involvement
2. I - 3mm or less horizontal attachment loss
   II - more than 3mm horizontal attachment loss but not through-and-through
   III - through-and-through lesion
3. Height of PDL, width of PDL, presence of inflammation, number/shape/length of roots
4. Progressively increasing, symptomatic, associated with deep pockets
5. 1 - <1mm bucco-lingual movement
   2 - 1-2mm bucco-lingual movement
   3 - >2mm bucco-lingual movement and/or rotation and depression
6. Splinting, correct plaque-induced inflammation, correct occlusal relations
7. Splinting - for mobility due to LoA, discomfort/chewing difficulties, stabilise teeth for debridement
   Doesn’t influence rate of disease (doesn’t slow rate), OH difficulties, Rx of last resort
8. Unfavourable occlusal forces, unfavourable soft tissue profiles, loss of attachment
9. Treat underlying perio, accept and stabilise, ortho and stabilise, extract, correct occlusal relations

Question 12

Antibiotics and antiseptics

1. 4 indications for antibiotics in dentistry
2. 4 problems with antibiotics in dentistry
3. 4 causes of antibiotic resistance
4. Definition of substantivity
5. 2 things substantivity depends on
6. What is CHX
7. Active ingredient in CHX
8. How does CHX work
9. 8 indications for CHX
10. 5 side effects of CHX

Answer 12

1. Immunocompromised patient (invasive Rx), spreading infection, systemic disease symptoms, inadequate mechanical therapy (reinfection from non-dental sites)
2. Unable to penetrate biofilms well, allergies, resistance, superinfection, ineffective without mechanical therapy, can be inactivated/degraded by non-target organisms
3. Trapped and destroyed by enzymes, inactive against non-growing organisms, expression of biofilm-specific resistance genes, may fail to penetrate beyond surface layers of biofilm, stress response to hostile environmental conditions
4. Persistence of action and ability to stick to the target - how long the agent works for
5. Maintenance of antimicrobial activity and slow neutralisation of antimicrobial activity
6. Chlorhexidine - an antiseptic
7. Bisbiguianide
8. Dicationic action - one cation adsorbs to tooth/pellicle and other cation sticks to bacteria. In low concentrations, causes increased cell permeability and at high concentrations causes cytoplasm precipitation (causing cell death)
9. Endo irritant, surgical scrub/hand-wash, pre-surgical mouthwash/aseptic technique, immunocompromised patients, limited manual dexterity/unable to perform self-care, oral candidiasis, RAS, NUG, post-RSD, post-extraction/surgery MW
10. Bitter taste, staining, taste disturbance, mucosal erosion, parotid swelling

Question 13

Periodontal treatment planning

1. 4 stages
2. 4 features of successful Rx
3. 4 aims of perio Rx
4. 3 side effects of perio Rx
5. 5 components of HPT
6. When to re-evaluate and why
7. 3 options at re-evaluation and why would they be indicated
8. 3 reasons for NSPT failure

Answer 13

1. HPT, re-evaluation, corrective therapy, supportive therapy
2. BoP <10%, reduction in probing depth, pockets <4mm or <5mm with bleeding, gain in attachment via junctional epithelium, improved OH (reduced BoP, plaque scores), no change in furcation/mobility
3. Arrest disease, regenerate lost tissue, maintain LT perio health, prevent tooth loss, improve soft tissue consistency for easier surgical management, evaluate patient motivation and plaque control
4. Recession, sensitivity, (initial) bleeding
5. DHE, OHI, supra-gingival scaling, sub gingival scaling (RSD), removal of other PRFs (replace defective restorations, margins, etc.), re-evaluate
6. 6-12 weeks. Longer allows better healing, attachment, replacement of junctional epithelium with pocket epithelium, etc.
7. Proceed with TP - good OH, inflammation resolved
   Repeat NSPT/supportive care - poor OH, persistent inflammation
   Repeat NSPT/regenerative/surgery - good OH, persistent deep pockets (BoP)
8. Inadequate debridement, poor compliance, host factors (smoking, poorly controlled diabetes)

Question 14

Periodontal surgery

1. 2 aims
2. 2 contraindications
3. 4 types of surgery
4. 2 aims of OFD
5. 3 features of post-OFD healing
6. 3 aims of gingivectomy
7. 4 indications for gingivectomy
8. 3 drugs that cause gingival overgrowth

Answer 14

1. Arrest disease by gaining access to complete RSD, regenerate lost perio tissues
2. Smoking, poor OH/plaque control
3. Access (OFD), regenerative (GTR), resective, mucogingival
4. Gain better access to roots
   Complete appropriate debridement
5. Organisation of blood clot, replacement by collagenous CT, attachment via long junctional epithelium, reduction in probing depths (gain in clinical attachment + gingival recession)
6. Facilitate patient cleaning/OH, improve aesthetics/appearance, facilitate restorative dentistry
7. Gingival enlargement/overgrowth, areas with difficult access, pseudopockets, idiopathic gingival fibromatosis, shallow supra bony pockets, minor corrective difficulties
8. Anticonvulsants (phenytoin), immunosuppressants (cyclosporine A), calcium-channel blocker (nifedipine)

Question 15

Furcation treatment

1. 2 aims
2. 4 types of treatment options
3. 1 indication for GTR
4. 4 types of elimination procedures
5. 3 indications for extraction

Answer 15

1. Eliminate plaque from exposed root complex, create expose surface anatomy that facilitates proper self-performed plaque control
2. Palliative, regeneration, repair, elimination procedures
3. Two and three-walled proximal defects, grade II mandibular furcation defects, grade II buccal maxillary furcation defects
4. Furcation plasty (create grade III furcation), tunnel prep (enlarge grade III), root resection/separation, hemisection, extraction
5. Non-functional tooth, gross mobility, little remaining attachment and recurrent symptoms

Question 16

Immunology

1. 3 key pathogens
2. Pathophysiology of gingivitis
3. Pathophysiology of periodontitis

Answer 16

1. P. gingivalis, T. denticola, T. forsythia, A. a
2. Increased PRR stimulation, increased production of pro-inflammatory mediators, causing inflammation. Increased vasodilation and immune cell migration. Amplification of healthy response
3. Biofilm extends into pocket and adaptive immune response predominates. Further amplification of pro-inflammatory processes, CT destruction (via MMPs) and alveolar bone resorption (RANKL) due to exacerbated uncontrolled immune responses