NZ Dental Hygiene REX common mistakes
NZ Dental Hygiene REX · Understand the traps and how to avoid them.
When asked about scope, the candidate answers with what a hygienist 'usually does' in their own workplace rather than citing the legal boundary set by the Health Practitioners Competence Assurance Act and the scope of practice defined by the Dental Council, and cannot say what must be referred to a dentist.
Candidates prepare from clinical habit and workplace custom, so they conflate local delegation policy with the statutory scope. They memorise tasks rather than the framework (HPCA Act, scope statements, competence standards) that determines who may do what, and under what supervision.
What to do instead
Build a one-page map: HPCA Act purpose and mechanisms, the Dental Council's defined scopes, the conditions attached to practising certificates, and a list of procedures that require referral or a specific authorisation. For each task, state the legal basis, not the workplace norm. Practise phrasing answers as 'permitted because... / must be referred because...'.
The candidate explains informed consent as 'the patient signed the form' and omits the elements of capacity, adequate disclosure of risks, alternatives and costs, the voluntary nature of consent, and the patient's right to withdraw consent at any time, including mid-treatment.
Consent is taught procedurally as paperwork, and candidates confuse documentation with the substantive legal test under the Code of Health and Disability Services Consumers' Rights (Right 7). They also forget that consent is a process, not an event, and that it must be revisited when the plan changes.
What to do instead
Learn Right 7 in its parts: presumption of competence, valid consent, informed choice, and the right to decline or withdraw. For any scenario, run a checklist: capacity, information given (including material risks and alternatives), freedom from coercion, and currency of the consent. Note explicitly when a treatment plan change triggers re-consent.
On a privacy scenario the candidate says information can be shared with a family member or another clinician because it is 'in the patient's best interests', without identifying the applicable rule under the Privacy Act 2020 and the Health Information Privacy Code, or the need for the patient's authorisation or a permitted exception.
Candidates rely on a general ethical instinct of beneficence and do not know the specific information privacy principles, the role of the Privacy Commissioner's code, or the distinction between sharing for continuity of care and disclosure to family. They also overlook that a competent patient controls disclosure.
What to do instead
Memorise the relevant information privacy principles (collection, storage and security, access and correction, limits on use and disclosure, unique identifiers) and the Health Information Privacy Code's health-specific modifications. For any disclosure question, ask: who is the patient, is there authorisation, is there a statutory exception, and what is the minimum information needed? State the rule before the ethical reasoning.
Cultural safety is answered as a slogan ('I treat everyone the same' or 'I am culturally aware') rather than as a measurable practice: examining the clinician's own power and bias, the patient's experience of care, partnership with whānau, use of interpreters, and responsiveness to Māori health inequities and Te Tiriti o Waitangi obligations in the health system.
Candidates confuse cultural awareness or sensitivity with cultural safety, and they answer from personal attitude rather than from the Dental Council's cultural competence standards and the concept that safety is defined by the patient, not the practitioner. Lack of familiarity with local terminology and frameworks produces vague answers.
What to do instead
Write out the distinction between awareness, sensitivity, competence and safety, and give two concrete behaviours for each that a patient could observe. Link to specific standards (Dental Council cultural competence, Health and Disability Commissioner expectations) and to an example of reducing inequity in access, communication or treatment. Use the patient-experience test in every answer.
In infection prevention and control, the candidate describes the steps of hand hygiene or instrument reprocessing but misplaces critical items in the Spaulding classification, or states that an item requires only disinfection when it penetrates tissue or contacts the vascular system and therefore requires sterilisation.
Candidates memorise sequences (clean, inspect, package, sterilise) without anchoring them to the classification of devices by risk. They also confuse cleaning with disinfection and disinfection with sterilisation, and they do not know which items are single-use.
What to do instead
Learn Spaulding as a decision tree: contact with intact skin (non-critical: cleaning, low-level disinfection), contact with mucous membranes or non-intact skin (semi-critical: high-level disinfection or sterilisation), entry into sterile tissue or the vascular system (critical: sterilisation). For a set of instruments, sort them by category first, then state the required process. Add the validation and monitoring requirements for the steriliser.
The candidate handles a sharps or blood exposure scenario by describing wound care only, omitting immediate reporting, source assessment, post-exposure prophylaxis pathways for bloodborne viruses, and the requirement to document and follow up. Similarly, they treat occupational health as a list of hazards without describing risk assessment and control.
Occupational health and safety is studied as a set of rules rather than as a process, and exposure incidents are emotionally charged and rarely rehearsed. Candidates do not know the hierarchy of controls or the local reporting obligations, and they underestimate the time-critical nature of HIV post-exposure prophylaxis.
What to do instead
Rehearse a written exposure algorithm: stop, wash, encourage bleeding for a puncture, report immediately, identify source and serology, assess risk, access prophylaxis within the window, baseline testing and follow-up, and incident documentation. Separately, learn the hierarchy of controls (eliminate, substitute, engineer, administer, PPE) and apply it to three hazards: sharps, aerosols and latex.
When describing periodontal assessment, the candidate reports probing depths as if they were attachment loss, does not record bleeding on probing or plaque scores in a standardised way, and cannot explain how to distinguish gingivitis from periodontitis or how to stage and grade a case using the current classification.
Candidates learn probing as a technique to produce a number rather than as a measurement whose interpretation depends on the gingival margin and on a standardised force and angulation. The 2018 classification's staging and grading dimensions are new material and are often memorised as labels without the defining variables.
What to do instead
Practise converting a full periodontal chart into a summary: for each site, state probing depth, recession, clinical attachment level, bleeding on probing and plaque. Then apply the classification step by step: severity and complexity for stage, rate of progression and risk factors for grade, plus extent. Write out how you would explain the diagnosis to a patient in two sentences.
Caries risk assessment is answered as a list of risk factors with no structured tool, no distinction between risk factors, indicators and protective factors, and no link from the identified risk to a specific recall interval, fluoride regimen, dietary intervention or sealant decision.
Candidates treat caries as a lesion to be counted rather than a dynamic process to be managed, so they list factors without weighting them and never close the loop from assessment to a tailored prevention plan. They also use a single risk tool as a tick box rather than as a basis for clinical decisions.
What to do instead
Use a recognised structured framework and practise the full pathway: gather disease indicators (past and present lesions), risk factors (diet, fluoride exposure, saliva, plaque control, medications) and protective factors; assign an overall risk category; then state the recall interval, fluoride product and concentration, dietary and self-care advice, and sealant or other intervention that follows from that category. Show the reasoning, not just the label.
In radiography, the candidate interprets an image beyond their scope, or answers a safety question by quoting a dose figure without the principles of justification, optimisation and dose limitation, without the ALARA/ALADA concept, and without the legal requirements for prescribing, recording and quality assurance of dental radiographs.
Candidates mix up the roles of prescriber and operator, and they learn radiation protection as a list of rules rather than as a framework. They also overreach in interpretation because they have seen many radiographs and assume that recognition equals diagnosis.
What to do instead
Separate three things in every answer: who may prescribe and why the exposure is justified; how the exposure is optimised (collimation, rectangular collimation, film/sensor selection, technique, repeat avoidance); and what the operator must record and quality-assure. For interpretation questions, describe findings and their differential, then state explicitly what is within a hygienist's scope and when to refer for a definitive diagnosis.
On oral medicine and pathology, the candidate lists possible conditions for a white or red lesion but does not describe a systematic examination (extraoral, intraoral, site, size, colour, texture, duration, tenderness, lymph nodes) or state the referral urgency and the red flags for malignancy.
Candidates focus on naming conditions rather than on the examination sequence and the decision to refer. They also lack a clear threshold for urgent referral and underestimate how much the history (duration, change, smoking and alcohol, prior lesions) changes the differential.
What to do instead
Memorise an examination sequence and a red-flag list (non-healing ulcer over two to three weeks, induration, fixation, unexplained bleeding, persistent red or mixed lesion, cervical lymphadenopathy, unilateral symptoms). For any lesion scenario, write the description in a standard order, give a ranked differential, and state the referral pathway and time frame. Practise describing lesions without committing to a definitive diagnosis.