ADC Written Exam (Dental Hygiene) flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Critical pH for enamel

The pH at which enamel begins to demineralize, approximately 5.5; below this value hydroxyapatite dissolves and caries can progress if the fall is frequent.

Oblique periodontal ligament fibres

The most numerous principal fibres of the periodontal ligament; they run from cementum coronally to alveolar bone and resist axial occlusal forces, converting them into tension on bone.

Porphyromonas gingivalis role

A Gram-negative anaerobic rod of the red complex, along with Tannerella forsythia and Treponema denticola, strongly associated with chronic periodontitis and tissue destruction.

Lidocaine maximum dose

For a healthy adult, lidocaine with epinephrine is limited to about 7 mg/kg, up to 500 mg; plain lidocaine is limited to 4.4 mg/kg, up to 300 mg.

Chorda tympani function

A branch of the facial nerve that carries taste from the anterior two-thirds of the tongue; it travels with the lingual nerve and synapses in the submandibular ganglion.

Type I collagen location

The principal collagen of dentine, bone, periodontal ligament and cementum; it forms strong fibrils and is deficient in osteogenesis imperfecta, which can cause dentinogenesis imperfecta-like teeth.

Parotid duct opening

Stensen's duct drains the parotid gland and opens into the oral cavity at the parotid papilla opposite the maxillary second molar, near the buccal mucosa.

Vitamin D and calcium

Calcitriol increases intestinal calcium and phosphate absorption; parathyroid hormone raises serum calcium by bone resorption and renal reabsorption, while calcitonin lowers serum calcium.

Working length in endodontics

The length from a coronal reference point to the apical constriction, usually 0.5-1 mm short of the radiographic apex, where instrumentation and obturation should terminate.

Sodium hypochlorite irrigation

An endodontic irrigant used at 0.5-5.25% that dissolves necrotic tissue, disinfects the canal and lubricates instruments; it must be kept away from periapical tissues because of toxicity.

Periodontal staging 2018

Stage I-III describes severity of periodontitis by interdental clinical attachment loss (1-2 mm, 3-4 mm, 5 mm or more); Stage IV adds need for complex rehabilitation due to tooth loss.

Hall technique indication

A paediatric technique in which a preformed metal crown is cemented over a primary molar with caries without tooth preparation, relying on separating the contacts and sealing the lesion.

Balanced occlusion in dentures

Simultaneous bilateral contact of maxillary and mandibular denture teeth in centric and eccentric positions, which stabilizes the prostheses and reduces tipping forces during function.

Inferior alveolar nerve block

A mandibular local anaesthetic technique targeting the inferior alveolar nerve near the mandibular foramen; it anaesthetizes mandibular molars, premolars and anterior teeth on the injected side.

First permanent molar eruption

The first permanent molar erupts at about 6 years of age, distal to the primary second molar, without replacing a primary tooth; it is highly susceptible to caries.

Class II malocclusion

A sagittal skeletal or dental relationship in which the mandible is retruded relative to the maxilla; the mandibular first molar is distal to its ideal Class I position.

Informed consent elements

Valid consent requires the patient to have capacity, receive adequate disclosure of risks and alternatives, act voluntarily, and comprehend the information before agreeing to treatment.

Autonomy in dental ethics

The principle that patients have the right to make their own healthcare decisions, which obliges clinicians to respect refusal, provide information and avoid coercion.

OARS in motivational interviewing

A core set of communication skills: open questions, affirmations, reflections and summaries, used to help patients explore and resolve ambivalence about behaviour such as smoking or oral hygiene.

Transtheoretical model stages

Precontemplation, contemplation, preparation, action and maintenance describe readiness to change; relapse can occur, and interventions should be matched to the patient's current stage.

Health Belief Model

Explains preventive behaviour by perceived susceptibility, severity, benefits and barriers, plus cues to action and self-efficacy; it is used to design oral health promotion messages.

Scope of practice principle

A dental hygienist must practise only within the competencies and legislative limits of the profession, referring patients to a dentist when findings exceed that scope.

Mandatory reporting duty

Health professionals must report suspected child abuse or neglect to the relevant authority, even when confidentiality would otherwise apply, because the safety of the child overrides privacy.

Teach-back communication method

A technique in which the clinician asks the patient to explain instructions in their own words, confirming understanding and allowing correction of misunderstandings before the patient leaves.

Water fluoridation concentration

Community water fluoridation is typically maintained at about 0.7 mg/L (ppm), a level that reduces dental caries while limiting the risk of dental fluorosis.

Fluoride varnish concentration

Professionally applied fluoride varnish usually contains 22,600 ppm fluoride (5% sodium fluoride) and is indicated for caries prevention in children and high-risk adults.

DMFT index

A caries measure counting decayed, missing and filled permanent teeth per person; for primary teeth the same components are recorded as dmft, with lowercase letters.

Incidence versus prevalence

Incidence is the number of new cases of a disease in a population over a period; prevalence is the total number of existing cases at a given time.

Autoclave sterilization parameters

Standard steam sterilization uses 134°C for 3 minutes (or 121°C for 15 minutes) at the required pressure, after cleaning and drying instruments in validated cycles.

Fissure sealant indication

Resin sealants are indicated for deep, susceptible pits and fissures of permanent molars, especially in children with caries risk, and are placed after isolation and etching.

Sharps injury immediate action

After a needlestick, wash the wound with soap and water, encourage bleeding, report immediately, and seek post-exposure prophylaxis assessment; do not scrub or use caustic agents.

Recall interval risk-based

Recall frequency should be set according to individual caries and periodontal risk rather than a fixed interval; low-risk adults may be reviewed less often than high-risk patients.