3 - Dentoalveolar Flashcards
1
Q
A
2
Q
3rd Molar Classification
A
- Descriptive
- Lower Third Molars
- Winters Angulation Classification
- Mesio - 45%
- Vertical - 40%
- Horizontal - 10%
- Distoangular - 5%
- Buccoangular
- Linguoangular
- Inverted
- Upper Third Molars
- Archer Classification
- 1 - Mesio
- 2 - Disto
- 3 - Vertical
- 4 - Horizontal
- 5 - Buccal
- 6 - Palatal
- 7 - Inverted
- Assessment of Difficulty
- WHARFE
Maximum Score 16- Winter’s Angulation Classification
- Height of mandible
- Angulation of 2nd Molar
- Root morphology
- Follicle size
- Exit pathway
- Pell and Gregory
-
Ramus assessment - Roman Numerals
- I - Anterior to ramus
- II - 50% within ramus
- III - completely within ramus
- Occlusal plane
- A - At occlusal plane
- B - Between occlusal plane and CEJ
- C - Below CEJ
-
Ramus assessment - Roman Numerals
- Winter’s Line
- White Line - Occlusal place
- Amber Line - Bone level
- Red Line - Perpendicular to occlusal plane to elevation point
Distance between Amber line to point of elevation is measured - Interpretation
- <5mm - LA
- >5mm - GA
- Every 1mm increases difficulty by 3x
- Pedersen Classification
- Pell and Gregory + Winters angulation
- Pell and Gregory + Winters angulation
- Lim Classification (Upper wisdom teeth)
- Archer + Relationship to the sinus and 7s
- WHARFE
3
Q
3rd Molar complications
A
- General risks with surgery
- Specific risks
- Nerve
- IAN
- Nguyen 2014
- Lingual
- Pichler 2001
- Temp 2% (7% with retraction)
- Perm 0.5%
- Pichler 2001
- IAN
- Infection
- Ren 2007
- 4% - Abx
- 6% - No Abx
- Ren 2007
- Dry socket
- Ren 2007
- 6% - Abx
- 14% - No Abx
- Ren 2007
- Fracture
- 1 in 25 000
- Nerve
4
Q
3rd Molar Difficulty Assessment
A
*
5
Q
3rd Molar Epidemiology and Overview
A
- Carter and Worthington 2016
- Impaction rate 25% of population
- 75% have 4 wisdom teeth
- 25% have 0-3 wisdom teeth
- Impaction theory
- Differential rate of growth of mesial and distal roots
- Inadequate arch space
- Tooth developmental lags behind jaw growth so can’t influence it
- Processed diet, better hygiene -> less dental loss -> inadequate space
6
Q
3rd Molar Indications and Contraindications
A
Indications
- Pathology - NICE 2000
- Periodontal
- Caries
- Infective
- Periapical
- Abscess
- Neoplastic
- Fracture
- Resorption 2nd Molar
- Prophylactic Removal
- AAMOS 2014
- Perio pocketing >5mm on 7s or in general
- Orthodontic or orthognathic interference
- Prosthodontics - Denture interference
- Symptomatic
- Food impaction
- Medical
- Immune suppression - Organ transplant
- Radiotherapy and Chemotherapy
- Implants - Joint prosthesis or other alloplastic implant
- Occupational
Prevention of mandible fracture - 2.8x Zhou- Military
- Professional contact sport
- Hyam 2018
- Disease negative, Symptom negative
- Patient
- Med Hx
- Finances
- Social
- Occupational/Hobbies
- Dental
- Difficulty
- Proximity to nerve & Risk of complications
- Surgeon
- Experience
- Experience
- Patient
- Disease negative, Symptom negative
- AAMOS 2014
Contraindications
- <12 yrs old - Unable to predict whether tooth will erupt
- >40 yrs old - Risk potentially outweigh benefits
- Medically compromised and unfit for surgery
- Limited MO
- Unable to accept IAN risk
- Surgeon experience
7
Q
ww.3rd Molar Nerve Injury
A
- AAOMS 2014
- 1% to 5% IAN (Temp + Permanant)
0-0.9% IAN (Permanant) - 0.4 - 1.5% Lingual (Temp + Permanant)
0 - 0.5% Lingual (Permanant)
- 1% to 5% IAN (Temp + Permanant)
- Nguyen 2014
- 0.68% - IAN (Temp + Permanant)
0.24% IAN (Permanant) - 0.15% - Lingual (Temp + Permanant)
0.079% - Lingual (Permanant)
- 0.68% - IAN (Temp + Permanant)
- Pichler 2001
- 8x more likely for lingual nerve injury with retraction
Lingual retraction was not protective for permanant nerve injury - 6.4% - Lingual retraction (Temp + Permanant)
0.6% - Lingual retraction (Permanant) - 0.6% No lingual retraction (Temp + Permanant)
0.2% - No lingual retraction (Permanant)
- 8x more likely for lingual nerve injury with retraction
8
Q
3rd Molar NICE Guideline review
A
- McArdle & Renton 2012 - The effects of NICE guidelines on management of third molars
- Removal of wisdom teeth
- Mean age increased 25 to 32 yrs old
- Initial decrease for removal in secondary care setting by 30%
But recent increase by over 97% - Caries and infection indication increased from 10% to 30%
- Population health
Increased cost per removal of wisdom teeth- Increased number of extractions in the secondary care setting (specialists)
- Increased numbers of GA vs LA
- Removal of wisdom teeth
9
Q
3rd Molar Perioperative Meds
A
- Antibiotics
- Pre op antibiotics - Ren 2007
- Dry socket: 14% to 6%
- Surgical site infection: 6% to 4%
- Post op antibiotics - Lodi 2012
- Indications
- Pre op infection
- Immunocompromised
- Higher risk of dry socket
- Female
- OCP
- Smoking
- Pericoronitis
- Prev dry socket
- Difficult extraction
- Indications
- Pre op antibiotics - Ren 2007
- Steroids
- Cho 2017
- Pre op reduces swelling and trimus
- Post op - No evidence
- Cho 2017
- Chlohexidine
- Cho 2017
- Reduces post op infection and dry socket
- Pre op rinse + Post op for 1/52
- Cho 2017
10
Q
3rd Molar Prophylactic Removal vs Retention
A
Indications for prophylactic removal
Hyam 2018
- Med Assessment
- Part of tumor resection
-
Pre-medication assessment
- Bisphosphonates
- Anticoagulants
- Pre-geriatric assessment
- Altered mental capacity
-
Reduced physical dexterity
- Tremors
- Neuromuscular disease
-
Pre-Treatment
- Radiotherapy
- Chemotherapy
-
Immuno-modifier therapy
- Bacteraemia
- Tissue-transfer patients
- Dental Assessment
- Orthodontics
- Orthognathic surgery
- Prosthodontic inhibitor
- Periodontal disease
- Financial
- Future loss of income during infective episodes
- One episode of recovery for removal of remaining wisdom teeth
- Insurance policy
- Social
- Military or scientific personal
- Sports and Hobbies
- Availability of home and community support
Risks of retention
Bouloux 2015
- 3% per yr of requiring removal
65% risk overall
McArdle & Renton 2012 - The effects of NICE guidelines on management of third molars
- Mean age increased 25 to 32 yrs old
- Initial decrease for removal in secondary care setting by 30%
But recent increase by over 97% - Caries and infection indication increased from 10% to 30%
- Retention Risks
- Caries 8, Caries 7
- 23% higher for mesioangular - Toedtling 2019 MA
- Periodontal complication
- Pericoronitis
- Periodontal defect of 7
- 38% of ppl with perio will worsen within 2 yrs - Ghaemin 2016
- Resorption of 2nd molar - 3% - Mercier 1992
- Deep space infection - 0.8% - Yoshi 2001
- Odontogenic cyst or tumor - 5% - Mello 2019
- Increased difficulty and complications with age - Pogrel 2019
- Benefits of removal before age 25
- 50% non impacted and 75% of impacted teeth fail to erupt - Kruger 2001
- After age 25 there is a 3% per yr risk of extraction
64% chance of teeth needing to be removed by age 43 - Bouloux 2015 - Reduced incidence of infection, dry socket, nerve injury, perio pocketing - Pogrel 2012
- 7s distant caries increases - 40% - McArdle 2019
- Benefits of removal before age 25
- Caries 8, Caries 7
11
Q
Apicectomy Indications and Contraindications
A
- Indications
- Orthograde root re-treatment not possible
- Dense GP
- Post core crown in situ
- Broken instument
- Complex root anatomy
- Calcified canals
- Iatrogenic displacement of material into root apex
- Fracture of 1/3 distal root tip
- Persistent lesion despite adequate Endo
- Orthograde root re-treatment not possible
- Contraindications
- Re-treatment not attempted
- Poor prognosis of tooth
- No coronal seal
- Apex near IAN or sinus
- Short roots
12
Q
Apicectomy Outcomes
A
- Retrograde filling material - Ma 2016 (Cochrane review)
- No difference in material
- No difference in material
- Outcomes - Beck-Boichsitter 2018
- 60% over 5 yrs, 50% over 10yrs
- Retrograde filling improves survival by 10%
- Retrograde filling improves survival by 10%
- Surgical vs Non surgical management - Del Fabbro 2007
- No difference is success outcome
- 60% over 5 yrs, 50% over 10yrs
13
Q
Canine impaction eruption prognosis
A
- Liu 2008
CBCT study- 45% - Buccal
- 40% - Palatal
- 10% - Mid alveolus
- Prognosis of eruption
- Ericson and Kurol 1987
Midline of lateral is the demarcation line- 91% - if lateral to midpoint of lateral
- 64% - if medial to midpoint of lateral
- Warford 2003
Broken into 4 zone based on the lateral- 94% - Lateral to lateral border of lateral incisor
- 62% - Between lateral border and midpoint of lateral incisor
- 13% - Between midpoint and medial border of lateral incisor
- 1% - Medial to medial border of lateral incisor
- Ericson and Kurol 1987
- Sequelae of nil treatment - RCSEng 2016 Guidelines
- 66% - Root resorption on laterals
*
- 66% - Root resorption on laterals
14
Q
Canine impaction risk factors
A
- Systemic
- Syndromes
- Gardners
- Cleidocranial dysplasia
- Downs
- Metabolic
- Hypothyroidism
- Hypopituitary
- XRT
- Syndromes
- Local factors
- Trauma
- Cleft
- Crowding
- Ankylosis of C
- Pathology
- Supernumerary
- Root dilaceration
15
Q
Canine impaction theories
A
- Genetics - Peck 1994
- Factors supporting genetics
- Anomalies associated with impacted canines
- Bilateral occurrence
- Gender predilection - more common in females
- Familial occurrence
- Population differences
- Factors supporting genetics
- Guidance theory - Becker 1995
- Missing lateral
- Peg lateral
