Periodontics and oral surgery
Diagnosis first, then complexity
Periodontology now follows the 2017 World Workshop framework: a patient is diagnosed with gingivitis or periodontitis, and periodontitis is described by stage (I–IV, reflecting severity and complexity) and grade (A–C, reflecting rate of progression using bone loss/age, smoking and diabetes). You must interpret the Basic Periodontal Examination: each sextant is screened with a WHO-12 probe and one code recorded - 0 (no pocket over 3.5 mm, no bleeding), 1 (bleeding), 2 (calculus or plaque retentive factors), 3 (pocket 4–5 mm), 4 (pocket 6 mm or more) - with an asterisk added where there is furcation involvement, mobility of 2 or more, or recession of 3.5 mm or more. Codes 3, 4 or an asterisk indicate that a full periodontal chart is needed.
Know when non-surgical therapy suffices, when surgical access or regeneration is justified, and how risk factors modify prognosis. In oral surgery, be secure on third molar assessment (Winter's angulation; Pell and Gregory for depth and ramus relationship), the anatomy behind inferior alveolar and lingual nerve injury, dry socket, haemorrhage control, MRONJ risk with antiresorptive drugs, and biopsy principles - formalin for routine histology, fresh or specific media for immunofluorescence and microbiology.
Worked example: a lower left sextant records a 6 mm pocket plus a furcation. You write '4*'; the asterisk does not alter the number, it flags complexity, prompting a full chart, further assessment and possible referral.
Traps: reading BPE codes as millimetres, confusing stage with grade, and omitting asterisk criteria.