ADC Written Exam (Dental Hygiene) common mistakes
ADC Written Exam (Dental Hygiene) · Understand the traps and how to avoid them.
Calculates local anaesthetic dose by counting cartridges ('two carpules is fine') instead of converting percentage concentration to mg/mL and multiplying by the patient's body weight against the maximum recommended dose.
Cartridge counting feels safe because it is what happens chairside, and candidates memorise 'max 2 carpules' as a rule rather than a dose. Percentage-to-mg/mL conversion is basic chemistry that was learned once and never practised under time pressure.
What to do instead
Before the exam, drill the single conversion (1% = 10 mg/mL; a 2.2 mL cartridge of 2% = 44 mg) until it is automatic. In every calculation question, write four things on scratch paper before looking at the options: concentration in mg/mL, volume, patient weight, and the mg/kg ceiling. Then check whether the question also imposes an epinephrine limit.
Answers cranial nerve and sensory-innervation questions by naming a nerve from memory rather than by mapping the reported deficit to a territory: for example, choosing a trigeminal lesion when the stem describes loss of taste on the anterior two-thirds of the tongue with preserved general sensation.
Anatomy is revised as lists of names and foramina, not as a set of bedside tests. When a stem presents a deficit pattern rather than a structure name, the rote list gives no handle to grip.
What to do instead
Build and memorise a three-column table for the oral region: structure tested, nerve supplying it, and the one-line clinical test (pinprick of lower lip, taste on anterior tongue, soft palate elevation, tongue protrusion). Practise by reading a deficit and working backwards to the nerve before reading options.
Selects the treatment that matches the headline diagnosis in the stem while ignoring the modifiers the stem deliberately planted: choosing scaling and root planing for every 'periodontitis' vignette regardless of smoking status, glycaemic control, compliance history, or residual probing depths after initial therapy.
Pattern recognition is fast and rewarding; the diagnostic label is the most salient word in the stem, and modifiers read as scene-setting rather than decision-changing information.
What to do instead
Adopt a fixed pre-answer routine: before reading the options, write a one-line profile of the patient (age, risk factors, compliance, site-specific findings, previous treatment). Then reject any option that would be the same answer if those modifiers were deleted.
Picks the correct intervention but places it in the wrong sequence, for example selecting definitive periodontal surgery when the stem describes an acute dentoalveolar abscess, or extracting a tooth before any attempt at cause-related therapy in a case with clear reversible aetiology.
Options are judged one at a time as 'is this a reasonable thing to do?' rather than as an ordered plan. Candidates are rarely taught to test the plan against a priority hierarchy.
What to do instead
Apply and rehearse a single ladder for every clinical stem: emergency/urgent management first, then cause-related and non-surgical care, then definitive/reconstructive care, then maintenance. Say the ladder stage out loud for each option and eliminate any option that skips a stage.
Chooses a definitive in-practice treatment for a presentation that should trigger referral, or conversely refers a condition that is clearly within the dental hygienist's scope: a chronic ulcer of more than two weeks' duration, a pigmented lesion with changing borders, unexplained bleeding, or an unstable medical patient.
Scope-of-practice and referral-trigger lists are learned as a document rather than as a set of red flags to be spotted in a vignette. Anxiety about 'doing something' pushes candidates towards active treatment options.
What to do instead
Memorise a short, hard list of referral triggers (duration, progression, unexplained bleeding, neurological deficit, suspicion of malignancy, uncontrolled systemic disease) and a short list of what is unambiguously within scope. For any stem containing a trigger, eliminate all in-practice definitive options first.
Answers ethical vignettes from personal moral preference rather than from the professional standard, for example refusing to continue care for a patient who declines a recommended treatment, or disclosing a patient's information to a family member because 'they are worried'.
Clinical questions have a factual right answer; ethical questions feel like opinion, so candidates answer as themselves instead of as a registered practitioner held to a published code.
What to do instead
Answer every ethics stem from the position 'what would a regulator expect me to be able to justify in writing?' Use a fixed framework: the four principles, the patient's right to autonomy and informed refusal, confidentiality with its narrow exceptions, and the boundary of one's own competence. Eliminate any option that removes patient choice or discloses information without consent.
Treats consent as a signature: selects 'obtain the patient's signature on the consent form' as the best answer when the scenario describes a patient who does not understand the proposed procedure, and treats a signed form as proof that consent was valid.
Consent is taught procedurally and the form is the visible artefact, so the paperwork becomes the remembered answer. The dialogue component has no tangible object to anchor to.
What to do instead
Rehearse the definition 'consent is a process, not a document': capacity, adequate information (diagnosis, options including doing nothing, material risks, costs, consequences of refusal), voluntary choice, and documented discussion. In vignettes, only choose an option that includes explanation and confirmation of understanding; treat the signature as the last, least important step.
Answers population-level public health stems with individual clinical solutions, or mixes up epidemiological measures, for example recommending chairside fluoride application for a community caries question, or reporting prevalence when the question asks for incidence.
The whole training is patient-at-a-time, so the default frame is the individual. Incidence and prevalence are both 'how common' words and are distinguished only by careful reading.
What to do instead
Label every public health stem 'population' or 'individual' before reading options, then discard options from the wrong level. Write the two definitions in one line each (prevalence = all cases existing at a point in time; incidence = new cases arising over a period) and practise classifying five stems into one or the other.
Applies a uniform six-month recall and identical prevention to every patient regardless of risk, answering prevention questions with a standard package rather than a risk-stratified one, and prescribing radiographs by habit rather than by stated selection criteria.
Uniform recall is the cultural norm and is easy to remember; risk-based recall requires a decision that candidates are afraid of getting wrong. Radiograph selection criteria are often memorised as a list of intervals rather than as a decision rule.
What to do instead
For each prevention stem, assign the patient to low, moderate or high caries and periodontal risk using the factors given (diet, fluoride exposure, salivary flow, smoking, diabetes, previous disease), and let the risk category drive recall interval, fluoride frequency and radiograph timing. Eliminate any option that gives the same package to a high-risk and a low-risk patient.
Chooses the clinically appealing option that quietly shortcuts practice-management obligations: skipping documentation of advice given and refused, reusing single-use items or abbreviating reprocessing steps to save time in a busy list, or ignoring the cost and staffing feasibility of a proposed change to the practice.
Practice-management content is studied last and feels like administration rather than clinical judgement, so in a mixed exam the clinical-sounding option wins by default. Infection-control and record-keeping standards are remembered as policies, not as behaviours.
What to do instead
Before selecting, run two filters on every option: 'would this survive an audit or a complaint investigation?' and 'is this deliverable with the staff, time and money the practice actually has?' Any option that leaves no written record, reuses a single-use device, or depends on unbudgeted resources is wrong regardless of its clinical merit.