EUC-ODON cheat sheet

2017 World Workshop classification uses staging (I–IV, severity/complexity) and grading (A–C, progression risk based on bone loss/age ratio, smoking, HbA1c).

Bone loss/age ratio: % radiographic bone loss at worst site divided by patient age; <0.25 = grade A, 0.25–1.0 = grade B, >1.0 = grade C.

Stage III periodontitis: probing depth ≥6 mm, horizontal bone loss extending to mid-third of root, ≤4 teeth lost; Stage IV adds ≥5 teeth lost, masticatory dysfunction, or bite collapse.

Periodontal health: probing depth ≤3 mm, bleeding on probing <10%, no attachment loss attributable to periodontitis.

Active periodontal therapy endpoints: residual pockets ≤4 mm, no site with BOP plus PD ≥5 mm; supportive care intervals typically 3–6 months based on risk.

Implant peri-implant mucositis = bleeding on gentle probing with no progressive bone loss; peri-implantitis = BOP plus progressive bone loss with increasing pocket depth.

Implant success criteria (Albrektsson): mean marginal bone loss <0.2 mm/year after first year, <1.5 mm in first year, no mobility, no pain, no radiolucency.

Risk factors with strongest evidence: smoking (dose-dependent), poorly controlled diabetes (HbA1c >7%), and plaque/biofilm accumulation.

Working length is commonly set 0.5–1.0 mm short of the radiographic apex; electronic apex locators are accurate within ±0.5 mm in most canals.

Root canal irrigants: sodium hypochlorite 0.5–5.25% for tissue dissolution and antimicrobial effect; EDTA 17% for smear layer removal; chlorhexidine as reserve for NaOCl allergy.

NaOCl extrusion can cause tissue necrosis and nerve injury; use side-vented needles, passive delivery, and never wedge a needle in a narrow canal.

Canal morphology: maxillary first molar typically has MB1, MB2, DB, and palatal canals; MB2 is present in the majority of cases and must be actively sought.

Access cavity principles: straight-line access, complete removal of pulp chamber roof, and location of all canal orifices before instrumentation.

Pulpal diagnosis: reversible pulpitis (provoked pain, resolves), symptomatic irreversible pulpitis (spontaneous or lingering pain), asymptomatic irreversible pulpitis (no symptoms, inflamed), necrotic pulp.

Periapical diagnosis: symptomatic apical periodontitis (pain to percussion), asymptomatic apical periodontitis, acute apical abscess (swelling, systemic signs), chronic apical abscess (sinus tract).

Instrumentation: crown-down or step-back; apical patency and recapitulation; NiTi rotary files reduce ledging and transportation compared with stainless steel hand files.

Occlusal vertical dimension is preserved by maintaining interocclusal rest space of roughly 2–4 mm at rest; excessive reduction causes angular cheilitis and loss of facial support.

Fixed partial denture abutment selection: crown-root ratio ideally ≥1:1, adequate periodontal support, and no more than one pier abutment between edentulous spaces.

Complete denture retention relies on adhesion, cohesion, atmospheric pressure, and border seal; the posterior palatal seal improves seal and comfort.

Centric relation is a maxillomandibular relationship independent of tooth contact; centric occlusion should coincide with centric relation in complete dentures.

Implant-supported prostheses: splinting multiple implants may reduce biomechanical load; cantilever length should be limited to reduce bending moments.

Occlusal scheme for complete dentures: bilateral balanced occlusion in eccentric movements; for implant-supported fixed prostheses, mutually protected or group function may be used.

Tooth preparation: finish line selection (chamfer for metal, shoulder for ceramic), axial reduction of 1.0–1.5 mm, and occlusal reduction of 1.5–2.0 mm for ceramic.

Removable partial denture design: use rests for support, clasps for retention, and major connectors that avoid gingival margins and hard palate midline.

Third molar extraction indications: recurrent pericoronitis, caries, periodontal disease, cyst/tumor, orthodontic need, and pathology; contraindications include uncontrolled systemic disease and high-risk proximity to the inferior alveolar nerve.

Inferior alveolar nerve injury risk increases with deep impaction, horizontal angulation, and proximity to the canal; cone-beam CT is indicated when the canal appears superimposed on the root.

Local anesthesia: maximum safe dose of lidocaine with epinephrine 1:100,000 is approximately 7 mg/kg (about 500 mg for a 70 kg adult); articaine 4% with epinephrine is limited to about 7 mg/kg.

Post-extraction bleeding management: pressure pack, local hemostatic agents (oxidized cellulose, gelatin sponge), tranexamic acid mouthwash, and suture; consider bleeding disorders.

Odontogenic infection spread: fascial spaces (submandibular, sublingual, buccal, pterygomandibular, lateral pharyngeal) require incision and drainage plus antibiotics when systemic signs are present.

Antibiotic prophylaxis for infective endocarditis is indicated for high-risk cardiac conditions (prosthetic valve, prior endocarditis, certain congenital heart disease) before invasive dental procedures.

Orthognathic surgery: Le Fort I osteotomy for maxillary repositioning, bilateral sagittal split osteotomy for mandible; preoperative orthodontics and model surgery are standard.

Fracture management: mandibular fractures commonly involve the angle, condyle, and parasymphysis; treatment options include closed reduction with maxillomandibular fixation or open reduction with internal fixation.

Angle classification: Class I (normal molar relationship), Class II (mandibular first molar distal to maxillary), Class III (mandibular first molar mesial to maxillary).

Cephalometric landmarks: SNA (maxillary position), SNB (mandibular position), ANB (skeletal relationship); ANB >4° suggests Class II skeletal pattern, <0° suggests Class III.

Growth modification: functional appliances for Class II in growing patients; facemask or chin cup for Class III; timing depends on pubertal growth spurt (CVM stage).

Arch expansion: rapid maxillary expansion (RME) separates the midpalatal suture in growing patients; slow expansion relies on dental tipping.

Anchorage control: maximum anchorage requires minimizing mesial movement of posterior teeth; temporary anchorage devices (TADs) provide absolute anchorage.

Extraction decisions: consider arch length discrepancy, profile, and anchorage; premolar extraction is common for severe crowding or bimaxillary protrusion.

Retention: fixed lingual retainers and removable retainers are used; relapse risk is highest in the first year and continues long term, especially for lower incisors.

Impacted canines: early detection via radiographs; interceptive treatment may include extraction of deciduous canine and space maintenance; surgical exposure and orthodontic traction for severe impaction.

Primary dentition eruption timeline: first tooth around 6 months, complete primary dentition by 2.5–3 years; first permanent molar erupts around 6 years.

Nursing bottle caries (early childhood caries) affects maxillary primary incisors first; mandibular incisors are typically spared due to tongue protection and salivary flow.

Fluoride varnish is recommended for caries prevention in children from first tooth eruption; professional application every 3–6 months for high-risk children.

Pulpotomy in primary teeth: formocresol or ferric sulfate; pulpectomy for irreversibly inflamed or necrotic pulp; stainless steel crowns for extensive decay.

Space maintenance: band-and-loop or crown-and-loop for premature loss of primary molars; space loss can cause impaction and crowding.

Behavior management: tell-show-do, positive reinforcement, and nitrous oxide sedation for anxious children; general anesthesia for extensive treatment or severe anxiety.

Trauma in primary teeth: intrusion may damage developing permanent tooth; avulsion of primary tooth generally not replanted; follow-up radiographs to monitor sequelae.

Eruption disturbances: ectopic eruption, ankylosis, and supernumerary teeth (mesiodens) require radiographic evaluation and timely intervention.

Oral potentially malignant disorders: leukoplakia, erythroplakia, oral submucous fibrosis, lichen planus, and actinic cheilitis; biopsy is indicated for persistent lesions.

Oral cancer red flags: non-healing ulcer >2 weeks, induration, fixation, lymphadenopathy, and unexplained bleeding; urgent referral for biopsy.

Aphthous ulcers: recurrent minor aphthae heal within 2 weeks; major aphthae are larger and heal with scarring; treatment includes topical corticosteroids and symptomatic care.

Oral lichen planus: white striae (Wickham striae), erosive forms; biopsy for diagnosis and to exclude dysplasia; avoid triggers and use topical steroids.

Radiographic interpretation: radiolucent lesions (cysts, tumors), radiopaque lesions (odontoma, osteoma, cementoblastoma); cone-beam CT for 3D assessment.

Periapical radiolucency differential: periapical granuloma, cyst, abscess, and non-endodontic lesions; vitality testing and biopsy when indicated.

Sjögren syndrome: dry mouth and eyes, parotid enlargement, positive anti-Ro/SSA and anti-La/SSB; increased risk of lymphoma.

Bisphosphonate-related osteonecrosis of the jaw: exposed bone >8 weeks in patients on antiresorptive therapy; prevention includes dental screening before starting therapy.

DMFT index: decayed, missing, filled teeth; DMFS for surfaces; used to measure caries experience in populations.

Community periodontal index (CPI) and basic periodontal examination (BPE) are used for screening and monitoring periodontal disease.

Fluoridation: community water fluoridation reduces caries prevalence; optimal level approximately 0.7–1.0 ppm depending on climate.

Oral health promotion: targeted interventions for high-risk groups (children, elderly, low-income); use of fluoride toothpaste and regular dental visits.

Epidemiology: prevalence = proportion with disease at a point in time; incidence = new cases over a period; both are essential for planning services.

Dental workforce planning: consider population-to-dentist ratio, access barriers, and rural/urban distribution.

Screening programs: school-based dental screenings, fluoride varnish programs, and sealant programs for caries prevention in children.

Health education theories: health belief model, stages of change, and social cognitive theory guide behavior change interventions.

Informed consent: patient must be competent, receive adequate information (risks, benefits, alternatives), and voluntarily agree; document the discussion.

Confidentiality: patient information must be protected; disclose only with consent or legal requirement; comply with data protection regulations.

Scope of practice: dentists must practice within their competence and refer when necessary; continuing education maintains competence.

Record keeping: accurate, contemporaneous, and legible records; retain according to legal requirements; records may be used in legal proceedings.

Infection control: standard precautions, sterilization of instruments, and proper waste disposal; follow national guidelines.

Practice management: appointment scheduling, recall systems, and financial management; patient satisfaction and communication are key.

Professional boundaries: avoid dual relationships; manage conflicts of interest; maintain professional conduct.

Advertising and marketing: must be truthful and not misleading; comply with regulatory standards.