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PMDC NLE Dental study materials
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PMDC NLE Dental practice questions

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Question 1Dental (NLE Dental) - domain breakdown not published in source

Which local anesthetic agent is available as a 4% solution and is most often selected for patients in whom vasoconstrictor-free anesthesia is required?

  1. Prilocaine Correct answer.
  2. Bupivacaine
  3. Lidocaine
  4. Mepivacaine

Explanation

Prilocaine is prepared as a 4% solution and is widely used when a plain anesthetic is needed; its low systemic toxicity allows the higher concentration. Lidocaine plain is supplied as 2%, bupivacaine as 0.5%, and mepivacaine plain as 3%.

Question 2Dental (NLE Dental) - domain breakdown not published in source

A patient reports a metallic taste, perioral tingling and a rising sensation of anxiety shortly after an inferior alveolar nerve block. Which stage of local anesthetic systemic toxicity is being described?

  1. Stage of muscular excitation
  2. Stage of medullary depression
  3. Stage of unconsciousness
  4. Stage of sensory excitation Correct answer.

Explanation

Local anesthetic toxicity progresses in stages: sensory excitation (tinnitus, metallic taste, perioral numbness, anxiety) precedes muscular excitation (twitching, convulsions), then unconsciousness and finally medullary depression. The described symptoms are all sensory phenomena, so the first stage is present.

Question 3Dental (NLE Dental) - domain breakdown not published in source

Which nerve block is most appropriate when anesthesia of the buccal soft tissues adjacent to the mandibular molars is required in addition to pulpal anesthesia of those teeth?

  1. Mental nerve block
  2. Inferior alveolar nerve block alone
  3. Greater palatine nerve block
  4. Buccal nerve block Correct answer.

Explanation

The buccal nerve supplies the cheek mucosa and buccal gingiva beside the mandibular molars and is not anesthetized by an inferior alveolar injection. A separate buccal nerve block is therefore required to anesthetize that soft tissue.

Question 4Dental (NLE Dental) - domain breakdown not published in source

During extraction of a mandibular first molar, the crown fractures and the roots remain. Which instrument is designed primarily to elevate and luxate retained roots?

  1. Root tip pick Correct answer.
  2. periosteal elevator
  3. Coupland elevator
  4. Straight elevator

Explanation

A root tip pick (apical elevator) has a fine, curved working end that engages a retained root within the socket and lifts it coronally. It is specifically designed for root retrieval rather than gross tooth elevation.

Question 5Dental (NLE Dental) - domain breakdown not published in source

Which suture material is classified as a monofilament, non-resorbable suture commonly used to close intraoral flaps?

  1. Chromic gut
  2. Silk
  3. Nylon Correct answer.
  4. Polyglactin 910

Explanation

Nylon (polyamide) is a monofilament, non-resorbable suture with low tissue reactivity and is widely used for intraoral closure. Polyglactin and chromic gut are resorbable, and silk is non-resorbable but multifilament.

Question 6Dental (NLE Dental) - domain breakdown not published in source

A patient presents with a firm, fluctuant swelling of the submandibular region and a raised floor of the mouth. Which fascial space infection is most directly threatened if the infection spreads posteriorly along the mylohyoid?

  1. Canine space
  2. Ludwig angina involving the submandibular and sublingual spaces bilaterally Correct answer.
  3. Sublingual space
  4. Infratemporal space

Explanation

Infection of the submandibular space can spread medially to involve the sublingual space and, if bilateral, produces Ludwig angina with elevation of the tongue and airway risk. The mylohyoid muscle is the key anatomical boundary between these spaces.

Question 7Dental (NLE Dental) - domain breakdown not published in source

Which clinical finding best differentiates a periapical abscess from a periodontal abscess on a radiograph and vitality test?

  1. Non-vital pulp with a widened periodontal ligament only
  2. Non-vital pulp with a periapical radiolucency Correct answer.
  3. Vital pulp with a deep periodontal pocket
  4. Vital pulp with generalized horizontal bone loss

Explanation

A periapical abscess arises from a necrotic pulp, so the tooth is non-vital and a periapical radiolucency is seen. A periodontal abscess typically occurs on a vital tooth with a deep pocket and intact periapical bone.

Question 8Dental (NLE Dental) - domain breakdown not published in source

Which irrigant is the standard choice for dissolving necrotic pulp tissue and providing antimicrobial action during root canal treatment?

  1. Saline
  2. Sodium hypochlorite Correct answer.
  3. Chlorhexidine gluconate
  4. Ethylenediaminetetraacetic acid

Explanation

Sodium hypochlorite is the primary endodontic irrigant because it dissolves organic tissue and has broad antimicrobial activity. EDTA is used to remove the smear layer and chlorhexidine provides substantivity but does not dissolve tissue.

Question 9Dental (NLE Dental) - domain breakdown not published in source

A working length is determined radiographically. Which anatomical landmark should the file tip reach for an accurate apical reference?

  1. The furcation
  2. The cementoenamel junction
  3. The apical constriction, about 0.5 to 1 mm short of the apex Correct answer.
  4. The radiographic apex

Explanation

The apical constriction is the narrowest part of the canal and the ideal termination point, generally 0.5 to 1 mm short of the radiographic apex. Instrumentation beyond this point risks extrusion of debris and irrigant.

Question 10Dental (NLE Dental) - domain breakdown not published in source

Which periodontal parameter is measured to assess clinical attachment loss?

  1. Probing depth alone
  2. Plaque index
  3. Probing depth plus gingival margin level relative to the cementoenamel junction Correct answer.
  4. Bleeding on probing

Explanation

Clinical attachment loss is calculated from the probing depth combined with the position of the gingival margin relative to the cementoenamel junction. Probing depth alone cannot distinguish recession from attachment loss.

Question 11Dental (NLE Dental) - domain breakdown not published in source

Which tooth surface is most commonly affected by root caries in an older adult with gingival recession?

  1. Incisal edge
  2. Buccal root surface Correct answer.
  3. Lingual of the maxillary incisors
  4. Occlusal surface

Explanation

Root caries occurs where cementum is exposed by recession, most often on buccal root surfaces. Occlusal and incisal surfaces are wear areas rather than typical root caries sites.

Question 12Dental (NLE Dental) - domain breakdown not published in source

A 12-year-old presents with a permanent maxillary central incisor that is unerupted while the adjacent lateral incisor has erupted. Which cause should be considered first?

  1. Ectopic eruption of the mandibular canine
  2. Premature loss of the primary incisor
  3. Ankylosis of the primary incisor
  4. Supernumerary tooth or odontoma obstructing eruption Correct answer.

Explanation

Failure of a permanent central incisor to erupt while adjacent teeth erupt suggests a physical obstruction such as a mesiodens or odontoma. Radiographic evaluation is indicated to identify and remove the obstruction.

Question 13Dental (NLE Dental) - domain breakdown not published in source

Which type of radiograph is most appropriate for assessing the entire dentition and both jaws in a new adult patient?

  1. Bitewing radiograph
  2. Occlusal radiograph
  3. Periapical radiograph of a single tooth
  4. Panoramic radiograph Correct answer.

Explanation

A panoramic radiograph provides a broad survey of both jaws, the dentition, and adjacent structures in a single image, making it suitable for initial assessment. Periapical and bitewing views are limited to localized detail.

Question 14Dental (NLE Dental) - domain breakdown not published in source

Which radiographic appearance is characteristic of a radicular cyst associated with a non-vital tooth?

  1. Ground-glass radiopacity
  2. Well-defined unilocular radiolucency at the apex Correct answer.
  3. Sunburst periosteal reaction
  4. Diffuse moth-eaten radiolucency

Explanation

A radicular cyst appears as a well-circumscribed unilocular radiolucency at the apex of a non-vital tooth, often with a sclerotic border. Moth-eaten, ground-glass, and sunburst patterns suggest other pathologies such as malignancy or fibrous dysplasia.

Question 15Dental (NLE Dental) - domain breakdown not published in source

A patient with a history of infective endocarditis requires a dental extraction. Which regimen is recommended for high-risk cardiac patients before the procedure?

  1. No prophylaxis is required
  2. Amoxicillin 500 mg three times daily for seven days after the procedure
  3. Amoxicillin 2 g orally one hour before the procedure Correct answer.
  4. Clindamycin 600 mg one hour before the procedure

Explanation

Current guidance recommends a single 2 g oral dose of amoxicillin one hour before the procedure for high-risk cardiac patients. Clindamycin is no longer recommended because of adverse events, and post-procedural courses are not the prophylactic approach.

Question 16Dental (NLE Dental) - domain breakdown not published in source

Which nerve is at greatest risk of injury during surgical removal of an impacted mandibular third molar?

  1. Inferior alveolar nerve Correct answer.
  2. Lingual nerve
  3. Facial nerve
  4. Chorda tympani

Explanation

The inferior alveolar nerve runs close to the roots of the mandibular third molar and is the nerve most frequently injured during its surgical removal. The lingual nerve is also at risk but less commonly affected.

Question 17Dental (NLE Dental) - domain breakdown not published in source

Which clinical sign suggests a malignant rather than a benign oral lesion?

  1. A soft, compressible lipoma
  2. Induration with fixation to underlying tissues Correct answer.
  3. A well-defined, freely movable mass
  4. A fluctuant cystic swelling

Explanation

Malignant lesions often show induration and fixation because of invasion into surrounding tissues. Benign lesions are typically well-defined, mobile, and non-infiltrative.

Question 18Dental (NLE Dental) - domain breakdown not published in source

Which condition presents with white, adherent patches on the oral mucosa that cannot be wiped off and carries a risk of malignant transformation?

  1. Linea alba
  2. Leukoplakia Correct answer.
  3. Geographic tongue
  4. Oral candidiasis

Explanation

Leukoplakia is a clinical term for a white patch that cannot be rubbed off and cannot be attributed to another disease; it is considered potentially malignant. Candidiasis can be wiped off, linea alba is a frictional keratosis, and geographic tongue is a red, depapillated lesion.

Question 19Dental (NLE Dental) - domain breakdown not published in source

A patient reports a sudden inability to close the right eye and drooping of the right corner of the mouth. Which diagnosis is most consistent with these findings?

  1. Myofascial pain
  2. Bell palsy Correct answer.
  3. Trigeminal neuralgia
  4. Temporomandibular joint disorder

Explanation

Peripheral facial nerve palsy (Bell palsy) produces ipsilateral inability to close the eye, loss of the nasolabial fold, and drooping of the mouth corner. Trigeminal neuralgia causes sharp pain in a division of the trigeminal nerve without motor weakness.

Question 20Dental (NLE Dental) - domain breakdown not published in source

Which factor most strongly increases the risk of osteoradionecrosis after extraction in a patient who received head and neck radiotherapy?

  1. Use of local anesthesia
  2. A radiation dose above 60 Gy to the mandible Correct answer.
  3. A short duration of treatment
  4. Extraction before radiotherapy

Explanation

Osteoradionecrosis risk rises with higher radiation doses, particularly doses above 60 Gy to the mandible, because of obliterative endarteritis and reduced bone vascularity. Timing and anesthesia technique are not the primary determinants.

Question 21Dental (NLE Dental) - domain breakdown not published in source

Which impression material is most appropriate when an accurate, dimensionally stable master cast is required for a fixed prosthesis?

  1. Alginate
  2. Zinc oxide eugenol paste
  3. Impression compound
  4. Addition silicone Correct answer.

Explanation

Addition silicone (polyvinyl siloxane) offers high dimensional stability, accuracy, and elastic recovery, making it suitable for master casts of fixed prostheses. Alginate is dimensionally unstable and used for study models.

Question 22Dental (NLE Dental) - domain breakdown not published in source

Which design feature of a removable partial denture framework helps direct functional forces along the long axis of the abutment teeth?

  1. Major connector
  2. Retentive mesh
  3. Clasp arms
  4. Rest seats Correct answer.

Explanation

Rest seats are prepared to receive the occlusal or cingulum rests and direct forces axially along the long axis of abutment teeth. Clasp arms provide retention, and the major connector joins components.

Question 23Dental (NLE Dental) - domain breakdown not published in source

Which property of a dental amalgam restoration is improved by increasing the mercury content within the permitted range?

  1. Marginal adaptation during carving Correct answer.
  2. Compressive strength
  3. Corrosion resistance
  4. Creep resistance

Explanation

A slightly higher mercury content improves plasticity, allowing better adaptation and carving of the restoration. However, excess mercury reduces strength, corrosion resistance, and creep resistance.

Question 24Dental (NLE Dental) - domain breakdown not published in source

Which local anesthetic is contraindicated in a patient with a documented allergy to ester-type anesthetics?

  1. Mepivacaine
  2. Lidocaine
  3. Articaine
  4. Benzocaine Correct answer.

Explanation

Benzocaine is an ester-type local anesthetic, and patients allergic to esters should avoid all ester agents because of cross-reactivity with para-aminobenzoic acid metabolites. Lidocaine, articaine, and mepivacaine are amides.

Question 25Dental (NLE Dental) - domain breakdown not published in source

Which clinical situation requires modification of the standard inferior alveolar nerve block technique?

  1. A patient who has eaten before the appointment
  2. A patient with controlled hypertension
  3. A patient with a history of a previous failed block due to accessory innervation Correct answer.
  4. A patient with a cold sore on the lip

Explanation

Accessory innervation, such as a bifid inferior alveolar nerve or a contribution from the mylohyoid nerve, can cause failure of a standard block and requires a modified or supplemental technique. Controlled hypertension, herpes labialis, and recent food intake do not alter the injection technique.

Question 26Dental (NLE Dental) - domain breakdown not published in source

A 45-year-old patient has generalized probing depths of 3-4 mm with no bleeding on probing and no attachment loss. Which diagnosis best fits this finding?

  1. Clinical gingival health Correct answer.
  2. Peri-implant mucositis
  3. Generalized periodontitis
  4. Gingival recession

Explanation

Probing depths up to 3 mm with no bleeding on probing and no clinical attachment loss define periodontal health. Periodontitis requires detectable attachment loss, which is absent here.

Question 27Dental (NLE Dental) - domain breakdown not published in source

Which pulp diagnosis applies when a tooth responds normally to cold testing but has a sharp, brief pain that resolves immediately after the stimulus is removed?

  1. Irreversible pulpitis
  2. Normal pulp
  3. Reversible pulpitis Correct answer.
  4. Pulpal necrosis

Explanation

Reversible pulpitis produces provoked pain that subsides promptly once the stimulus is removed and vitality testing is positive. Irreversible pulpitis typically gives lingering pain, while necrosis gives no response.

Question 28Dental (NLE Dental) - domain breakdown not published in source

Which local anesthetic property best explains why 2% lidocaine with 1:100,000 epinephrine provides hemostasis during a minor surgical procedure?

  1. Rapid hepatic metabolism of lidocaine
  2. Low pKa of the lidocaine base
  3. Vasoconstriction from the epinephrine Correct answer.
  4. Intrinsic vasodilating action of lidocaine

Explanation

Epinephrine is a vasoconstrictor that reduces local blood flow, giving hemostasis and prolonging anesthetic duration. Lidocaine itself is a vasodilator, so the vasoconstrictor is what produces the hemostatic effect.

Question 29Dental (NLE Dental) - domain breakdown not published in source

Which tooth is most frequently impacted after the mandibular third molar?

  1. Maxillary first molar
  2. Mandibular first premolar
  3. Maxillary canine Correct answer.
  4. Mandibular canine

Explanation

After the mandibular third molar, the maxillary canine is the most commonly impacted tooth, largely because it erupts late and must travel a long path. Mandibular canines and premolars are impacted far less often.

Question 30Dental (NLE Dental) - domain breakdown not published in source

Which primary tooth condition most directly threatens the developing permanent successor?

  1. A shallow occlusal enamel fracture of the primary molar
  2. Normal exfoliation of the primary central incisor
  3. A periapical infection of the primary molar Correct answer.
  4. Physiologic root resorption of the primary incisor

Explanation

Infection from a primary tooth can spread to the developing permanent tooth germ, causing enamel hypoplasia or eruption disturbance. Physiologic resorption and normal exfoliation are expected processes, and a shallow enamel fracture does not reach the pulp.

Question 31Dental (NLE Dental) - domain breakdown not published in source

Which radiograph is the standard first-line imaging choice for detecting proximal caries in the posterior teeth of an adult?

  1. Lateral cephalometric radiograph
  2. Panoramic radiograph
  3. Occlusal radiograph
  4. Bitewing radiograph Correct answer.

Explanation

Bitewing radiographs show the crowns of upper and lower posterior teeth together and detect proximal caries with good sensitivity. A panoramic view lacks the resolution for early proximal lesions, and cephalometric and occlusal films do not serve this purpose.

Question 32Dental (NLE Dental) - domain breakdown not published in source

Which hand instrument is designed primarily for removing supragingival calculus from the facial surfaces of posterior teeth?

  1. Periodontal probe
  2. Excavator
  3. Explorer
  4. Sickle scaler Correct answer.

Explanation

Sickle scalers have a pointed tip and triangular cross-section for removing supragingival calculus from crown surfaces. Probes measure pocket depth, explorers detect caries and calculus, and excavators remove carious dentin.

Question 33Dental (NLE Dental) - domain breakdown not published in source

Which suture material is classified as non-resorbable and is commonly used to close an oral surgical wound?

  1. Polyglactin 910
  2. Silk Correct answer.
  3. Plain gut
  4. Chromic gut

Explanation

Silk is a non-resorbable braided suture that requires removal after healing. Plain gut, chromic gut, and polyglactin 910 are all resorbable materials that degrade over time.

Question 34Dental (NLE Dental) - domain breakdown not published in source

A patient with a history of anaphylaxis to penicillin requires a prophylactic antibiotic before a dental procedure. Which agent is the appropriate alternative?

  1. Ampicillin
  2. Penicillin V
  3. Amoxicillin
  4. Clindamycin Correct answer.

Explanation

When a patient has a documented penicillin allergy, a non-beta-lactam such as clindamycin is an appropriate alternative. Amoxicillin, ampicillin, and penicillin V are all penicillins and would risk a cross-reaction.

Question 35Dental (NLE Dental) - domain breakdown not published in source

Which factor most increases the risk of bisphosphonate-related osteonecrosis of the jaw in a patient starting therapy?

  1. Use of calcium supplements
  2. Oral route at low dose
  3. Topical application
  4. Intravenous route of administration Correct answer.

Explanation

Intravenous bisphosphonates, especially in cancer therapy, carry a much higher risk of osteonecrosis than oral low-dose regimens used for osteoporosis. The route and potency of the drug are the dominant risk determinants.

Question 36Dental (NLE Dental) - domain breakdown not published in source

A patient presents with a unilateral vesicular rash in a band along the ophthalmic division of the trigeminal nerve. Which diagnosis is most likely?

  1. Recurrent herpes labialis
  2. Aphthous ulcer
  3. Herpes zoster Correct answer.
  4. Oral candidiasis

Explanation

A dermatomal vesicular eruption along a trigeminal division is the classic presentation of herpes zoster, reflecting reactivation of varicella-zoster virus in a sensory ganglion. Aphthous ulcers and herpes labialis are localized, and candidiasis produces removable white plaques.

Question 37Dental (NLE Dental) - domain breakdown not published in source

Which feature best distinguishes a benign from a malignant salivary gland swelling on clinical examination?

  1. Bilateral symmetrical enlargement
  2. Fixed mass with nerve palsy Correct answer.
  3. Soft and freely movable mass
  4. Gradual increase in size over years

Explanation

Fixation to surrounding tissues and facial nerve palsy suggest malignant infiltration of a salivary gland tumor. Benign tumors are typically mobile, slow-growing, and do not cause nerve deficit.

Question 38Dental (NLE Dental) - domain breakdown not published in source

Which occlusal scheme is most appropriate for a complete denture to reduce lateral forces on the residual ridge?

  1. Monoplane occlusion with no cusps
  2. Balanced occlusion with bilateral contacts Correct answer.
  3. Group function on the working side
  4. Steep cuspal anatomy

Explanation

Balanced occlusion ensures simultaneous contacts on both sides during excursions, distributing forces and stabilizing the dentures. Steep cusps or group function increase lateral loading and destabilize the prosthesis.

Question 39Dental (NLE Dental) - domain breakdown not published in source

Which property of a glass ionomer cement makes it useful for restoring cervical lesions in a patient with high caries risk?

  1. Sustained fluoride release Correct answer.
  2. Low solubility in oral fluids
  3. Excellent esthetics
  4. High compressive strength

Explanation

Glass ionomer cements release fluoride over time, which helps inhibit secondary caries in high-risk patients. Their strength and esthetics are inferior to resin composites, and their solubility is relatively high.

Question 40Dental (NLE Dental) - domain breakdown not published in source

A patient reports that the maxillary complete denture dislodges during speech. Which factor is most likely responsible?

  1. Inadequate posterior palatal seal Correct answer.
  2. Excessive border extension
  3. Overextended lingual flange
  4. Too little relief over the incisive papilla

Explanation

The posterior palatal seal provides a valve-like seal at the junction of the hard and soft palate, and its loss causes dislodgement during speech. Excessive relief over the incisive papilla does not create a seal.

Question 41Dental (NLE Dental) - domain breakdown not published in source

Which tooth preparation feature is essential for the retention of a cast post-and-core in an endodontically treated anterior tooth?

  1. A post with a square cross-section
  2. A post length of at least half the root length Correct answer.
  3. Complete removal of the ferrule
  4. A post diameter equal to the root width

Explanation

A post should extend roughly half to two-thirds of the root length to gain retention while preserving apical seal. An oversized post risks root fracture, and a ferrule should be preserved rather than removed.

Question 42Dental (NLE Dental) - domain breakdown not published in source

Which clinical finding indicates a need for endodontic retreatment in a previously treated tooth?

  1. Adequate obturation length
  2. A well-adapted coronal restoration
  3. Persistent periapical radiolucency with symptoms Correct answer.
  4. Absence of symptoms for one year

Explanation

A persistent or enlarging periapical lesion with symptoms after root canal treatment suggests failure and warrants retreatment. A well-adapted restoration and adequate obturation are favorable findings, and a symptom-free year suggests success.

Question 43Dental (NLE Dental) - domain breakdown not published in source

Which local anesthetic is an ester-type agent?

  1. Articaine
  2. Mepivacaine
  3. Benzocaine Correct answer.
  4. Lidocaine

Explanation

Benzocaine is an ester local anesthetic, metabolized by plasma esterases and more likely to cause allergy. Lidocaine, mepivacaine, and articaine are amide agents.

Question 44Dental (NLE Dental) - domain breakdown not published in source

Which nerve block is preferred when a mandibular molar requires anesthesia but the standard inferior alveolar block fails due to accessory innervation?

  1. Mental nerve block
  2. Gow-Gates block Correct answer.
  3. Long buccal nerve block
  4. Nasopalatine nerve block

Explanation

The Gow-Gates technique deposits solution higher at the condylar neck, anesthetizing the inferior alveolar, lingual, mylohyoid, and buccal nerves and overcoming accessory innervation. Mental and long buccal blocks do not anesthetize the pulpal supply to mandibular molars.

Question 45Dental (NLE Dental) - domain breakdown not published in source

A patient has a swelling of the floor of the mouth that raises the tongue and is fluctuant. Which condition is most likely?

  1. Pleomorphic adenoma
  2. Fibroma
  3. Ranula Correct answer.
  4. Mucocele of the lower lip

Explanation

A ranula is a mucocele arising from the sublingual gland that presents as a fluctuant floor-of-mouth swelling displacing the tongue. Pleomorphic adenoma is a firm gland tumor, fibroma is a firm reactive mass, and a lower lip mucocele is located on the lip.

Question 46Dental (NLE Dental) - domain breakdown not published in source

Which mechanism best explains the analgesic action of a local anesthetic at the nerve membrane?

  1. Inhibition of cyclooxygenase
  2. Blockade of voltage-gated sodium channels Correct answer.
  3. Blockade of potassium channels
  4. Agonism at opioid receptors

Explanation

Local anesthetics block voltage-gated sodium channels in the axon membrane, preventing depolarization and impulse conduction. Potassium channel blockade, cyclooxygenase inhibition, and opioid agonism are unrelated mechanisms.

Question 47Dental (NLE Dental) - domain breakdown not published in source

A patient with a restored maxillary central incisor develops a gray discoloration and a sinus tract. Which finding on vitality testing and radiography would best support a diagnosis of a necrotic pulp with periapical abscess?

  1. Normal response to cold and a widened periodontal ligament
  2. Normal response to cold and a periapical radiolucency
  3. No response to cold and a periapical radiolucency Correct answer.
  4. Exaggerated response to cold and no radiolucency

Explanation

A necrotic pulp does not respond to thermal testing and is associated with periapical bone loss. A normal or exaggerated cold response indicates a vital pulp, which excludes necrosis.

Question 48Dental (NLE Dental) - domain breakdown not published in source

A patient with severe periodontitis and poorly controlled diabetes asks about treatment sequencing. Which approach is most appropriate?

  1. Proceed with implants before periodontal therapy
  2. Delay all periodontal therapy until HbA1c is normal
  3. Perform extractions without antibiotic coverage
  4. Coordinate periodontal therapy with glycemic control Correct answer.

Explanation

Periodontal treatment and glycemic control are mutually beneficial, so therapy should proceed while medical management is coordinated. Waiting for a normal HbA1c delays care indefinitely, and implants should follow periodontal stabilization.

Question 49Dental (NLE Dental) - domain breakdown not published in source

A patient with a mandibular fracture has anesthesia of the lower lip and chin on the affected side. Which structure is most likely injured?

  1. Long buccal nerve
  2. Chorda tympani
  3. Inferior alveolar nerve Correct answer.
  4. Mylohyoid nerve

Explanation

The inferior alveolar nerve supplies sensation to the lower lip and chin, so its injury from a mandibular fracture causes numbness in that distribution. The long buccal, mylohyoid, and chorda tympani nerves serve other territories.

Question 50Dental (NLE Dental) - domain breakdown not published in source

Which radiographic feature best distinguishes a dentigerous cyst from a radicular cyst?

  1. Ill-defined borders with root resorption
  2. Attachment at the apex of a non-vital tooth
  3. Attachment at the cementoenamel junction of an unerupted crown Correct answer.
  4. Presence of calcifications within the lumen

Explanation

A dentigerous cyst encloses the crown of an unerupted tooth and attaches at the cementoenamel junction, whereas a radicular cyst is at the apex of a non-vital tooth. Calcifications suggest an odontogenic tumor such as an adenomatoid odontogenic tumor.