Iran Dental Residency Entrance Exam flashcards

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

Ameloblastoma

Benign but locally aggressive odontogenic epithelial tumor, most common in the posterior mandible, showing multilocular radiolucency and high recurrence after conservative curettage.

Odontogenic keratocyst lining

Parakeratinized stratified squamous epithelium with palisaded hyperchromatic basal cells and corrugated keratin, associated with PTCH1 mutations and high recurrence.

Pleomorphic adenoma

Most common salivary gland tumor, usually in the parotid, with epithelial and myoepithelial cells in chondromyxoid stroma and a capsule that may be incomplete.

Pemphigus vulgaris immunofluorescence

Direct immunofluorescence shows intercellular IgG in a net-like pattern within the epithelium because of suprabasal acantholysis, producing intraepithelial blisters.

Cervical burnout

Radiolucency at the tooth neck caused by reduced X-ray attenuation between enamel and alveolar crest, lacking the triangular shape and dentinal spread of caries.

Cone-beam CT resolution

Provides isotropic sub-millimeter spatial resolution with lower dose than multidetector CT but poorer soft-tissue contrast, useful for implant and endodontic planning.

Paralleling technique

Receptor is placed parallel to the tooth long axis with the central beam perpendicular, minimizing distortion compared with the bisecting-angle technique.

Bitewing radiograph

Shows crowns of maxillary and mandibular teeth on one image and is the preferred view for detecting proximal caries and monitoring alveolar crest height.

Erythroplakia

Persistent red mucosal patch that cannot be attributed to another cause and carries the highest malignant transformation risk among oral potentially malignant disorders.

Trigeminal neuralgia treatment

Carbamazepine is first-line for paroxysmal electric-shock pain in V2 or V3; atypical features or sensory loss require MRI to exclude secondary causes.

Pseudomembranous candidiasis

White plaques that wipe off leaving an erythematous base; predisposed by inhaled steroids, xerostomia, diabetes, and immunosuppression; treated with topical or systemic antifungals.

Hyposalivation threshold

Unstimulated whole salivary flow below 0.1 mL per minute defines hyposalivation and supports use of sialagogues and topical fluoride.

Working length endpoint

Apical constriction lies about 0.5 to 1.0 mm short of the radiographic apex and is the preferred instrumentation limit to reduce extrusion.

Sodium hypochlorite function

Dissolves organic tissue and kills microorganisms in the canal but does not remove the smear layer, which requires EDTA or acid chelation.

Vertucci type IV canal

Two separate canals run from the pulp chamber to the apex without merging, a configuration that requires independent cleaning and shaping of both canals.

Irreversible pulpitis

Spontaneous or lingering pain after thermal stimulus indicates irreversible pulpal inflammation and usually requires root canal treatment or extraction.

Clinical attachment level

Distance from the cementoenamel junction to the pocket base; more reliable than pocket depth for documenting past periodontal destruction and monitoring change.

Guided tissue regeneration

Barrier membrane excludes epithelium and connective tissue so periodontal ligament and bone cells repopulate the defect, most effective in intrabony defects.

Peri-implant mucositis

Reversible inflammation of peri-implant soft tissue without progressive bone loss, distinguished from peri-implantitis by the absence of bone loss.

Chamfer finish line

Rounded finish line used for metal and metal-ceramic crowns, providing adequate bulk while allowing a recordable margin without a sharp internal angle.

Ante's rule

A fixed partial denture is indicated when the total periodontal surface area of abutment roots equals or exceeds that of the missing teeth.

Addition silicone impression

Polyvinyl siloxane with high dimensional stability and elastic recovery, suitable for precise fixed prosthodontic impressions and pouring at a later time.

Neutral zone

Space where forces from lips, cheeks, and tongue balance; arranging denture teeth within this zone improves stability of the mandibular prosthesis.

Kennedy Class I

Bilateral edentulous areas located posterior to the remaining natural teeth, producing a distal extension situation on both sides of the arch.

Two-implant mandibular overdenture

Supported by the McGill consensus as first-choice treatment for the edentulous mandible, improving retention and satisfaction compared with conventional dentures.

Composite polymerization shrinkage

About 2 to 3 percent volumetric contraction during curing causes cuspal deflection and microleakage, reduced by incremental layering and adhesive bonding.

Zirconia transformation toughening

Tetragonal to monoclinic phase change near a crack tip creates compressive stress that resists crack propagation, giving high flexural strength.

Ferrule effect

A 1.5 to 2.0 mm collar of sound tooth structure around a post and core improves fracture resistance of the restored tooth.

Nolla stage 6

Marks completed crown formation of a permanent tooth, useful for estimating dental age and timing of interceptive or surgical treatment.

Stainless steel crown indication

Used for extensive caries, after pulpotomy, and in hypoplastic primary molars, requiring occlusal reduction and adequate proximal clearance before cementation.

ANB angle

Cephalometric angle averaging about 2 degrees; increased values suggest skeletal Class II and decreased or negative values suggest skeletal Class III.

Arch wire stiffness

Stiffness rises with the fourth power of wire diameter, so small increases in diameter markedly reduce flexibility and increase force delivery.

Ludwig angina

Bilateral infection of submandibular, sublingual, and submental spaces with board-like floor of mouth; requires airway protection, drainage, and intravenous antibiotics.

Inferior alveolar nerve block

Anesthetizes mandibular teeth, buccal gingiva anterior to the mental foramen, and lower lip; lingual soft tissue needs a separate lingual nerve block.

RANKL and osteoprotegerin

RANKL activates osteoclast differentiation while osteoprotegerin acts as a decoy receptor inhibiting RANKL; the ratio determines net bone resorption.

Secretory IgA

Dominant immunoglobulin in saliva and mucosal secretions, neutralizing pathogens at mucosal surfaces without activating complement.