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Which specific malocclusion feature, when corrected in adulthood, has the highest likelihood of showing a statistically significant improvement in phonetic articulation (e.g., elimination of a frontal lisp) according to speech pathology studies?

 # Which specific malocclusion feature, when corrected in adulthood, has the highest likelihood of showing a statistically significant improvement in phonetic articulation (e.g., elimination of a frontal lisp) according to speech pathology studies? A. Maxillary incisor protrusion with anterior open bite (Interdental gap) B. Unilateral posterior crossbite C. Severe class II division 2 deep bite D. Mild crowding of the mandibular anterior teeth The correct answer is A.  Maxillary incisor protrusion with anterior open bite (Interdental gap) The malocclusion feature correction that shows the highest likelihood of a statistically significant improvement in phonetic articulation (e.g., elimination of a frontal lisp) in adulthood is: Maxillary incisor protrusion with anterior open bite (Interdental gap) Rationale from Speech Pathology Studies The correction of a malocclusion that eliminates an anterior open bite and reduces excessive maxillary incisor protrusion (overjet) is the mo...

A potential iatrogenic adverse consequence of treating maxillary incisor proclination with retraction mechanics is a decrease in the:

 # A potential iatrogenic adverse consequence of treating maxillary incisor proclination with retraction mechanics is a decrease in the: A. Depth of the nasolabial angle due to soft tissue retraction B. Vertical height of the alveolar process in the anterior mandible C. Maxillary incisor root proximity to the nasal floor and palatal cortex D. Posterior arch width due to transverse forces The correct answer is C. Maxillary incisor root proximity to the nasal floor and palatal cortex When maxillary incisors are retracted (moved backward) to correct proclination (forward tipping), the entire tooth structure, including the root, moves posteriorly. The root apices of the maxillary incisors are naturally close to the nasal floor superiorly and the palatal cortical plate posteriorly. Significant retraction, especially with bodily movement or lingual tipping, can push the root apices closer to these anatomical boundaries. This decreased proximity (i.e., the distance becomes smaller) incre...

The primary benefit of early (Phase I) correction of a mandibular functional shift is to:

 # The primary benefit of early (Phase I) correction of a mandibular functional shift is to: A. Improve the patient’s TMJ range of motion in maximal opening B. Prevent asymmetric growth and irreversible skeletal asymmetry of the mandible C. Reduce the risk of buccal non carious cervical lesions D. Avoid extraction of premolar teeth in the permanent dentition The correct answer is B. Prevent asymmetric growth and irreversible skeletal asymmetry of the mandible Mandibular functional shifts, typically from unilateral posterior crossbite, cause the mandible to deviate laterally (1–3 mm) into centric occlusion to bypass interferences, altering condylar positioning and asymmetric loading during growth—leading to differential mandibular ramus/fossa remodeling (e.g., 1–2 mm longer body on shifted side) and progressive skeletal asymmetry (chin deviation, facial canting) that becomes increasingly fixed post-puberty. Phase I correction (e.g., rapid maxillary expansion in mixed dentition) eli...

An uncorrected anterior open bite with a tongue thrust habit can lead to an adverse consequence in the dental alveolar complex via a mechanism of:

 # An uncorrected anterior open bite with a tongue thrust habit can lead to an adverse consequence in the dental alveolar complex via a mechanism of: A. Disruption of the equilibrium between tongue and lip muscle forces B. Increased risk of periodontal bone loss due to heavy occlusal forces C. Pathologic attrition of the posterior teeth D. Skeletal mandibular retrusion The correct answer is A. Disruption of the equilibrium between tongue and lip muscle forces In uncorrected anterior open bite with tongue thrust, the aberrant lingual pressure during deglutition and speech exerts a supracrestal force (20–50 N) on the lingual inclines of maxillary and mandibular incisors, overriding the restraining orbicularis oris and mentalis tonicity—resulting in progressive labial flaring, anterior spacing, and failure of spontaneous closure, with alveolar bone remodeling adapting to this disequilibrium (e.g., reduced interradicular bone density via osteoclast activation). This perioral imbalance ...

Primary goal of pre-orthodontic or phase I alignment of severely crowded incisors

 # The primary goal of pre-orthodontic or phase I alignment of severely crowded incisors that are planned for permanent extraction (e.g. premolar) is to: A. Reduce the risk of post treatment gingival recession B. Decrease the overall duration of the comprehensive treatment C. Prevent external apical root resorption of adjacent teeth D. Align the roots parallel for optimal force distribution during space closure The correct answer is D. Align the roots parallel for optimal force distribution during space closure In extraction cases with severe incisor crowding, initial (phase I) alignment using light round NiTi wires uprights and derotates the anterior teeth, paralleling their roots to position the center of resistance (CR) along the retraction force vector—enabling bodily translation rather than uncontrolled tipping during subsequent en masse space closure (e.g., via chain or coil springs). This optimizes biomechanical efficiency, reduces unwanted extrusion or lingual crown tipping...

The benefit of orthodontic correction for a single tooth with infraocclusion is primarily to:

 # The benefit of orthodontic correction for a single tooth with infraocclusion is primarily to: A. Improve the patient's vertical dimension of occlusion (VDO) B. Eliminate the need for prosthetic replacement of the tooth C. Reduce the risk of periodontal bone loss on the adjacent teeth D. Prevent future TMJ derangement and pain The correct answer is C. Reduce the risk of periodontal bone loss on the adjacent teeth. Uncorrected infraocclusion (often from ankylosis) causes compensatory tipping and overeruption of adjacent teeth (e.g., first permanent molar mesially tilting into the space), leading to eccentric occlusal loading, plaque stagnation in tilted contacts, and progressive alveolar bone resorption on those neighbors—up to 1–2 mm loss over 1–2 years if severe. Orthodontic intervention restores occlusal plane integrity, preventing this cascade: studies show it minimizes adjacent tipping by 70–90%, preserving arch length, symmetry, and periodontal health (e.g., stable probing d...

Adverse consequence of malocclusion with the highest correlation with a patient's socio-economic status

 # Which adverse consequence of malocclusion has the highest correlation with a patient's socio-economic status and access to dental care, rather than the malocclusion's severity alone? A. Functional lateral mandibular shift B. Increased risk of incisor trauma C. Pathologic attrition leading to dentin exposure D. Early and severe development of dental caries The correct answer is D. Early and severe development of dental caries Crowding and irregular alignment in malocclusion create plaque-retentive areas that hinder effective oral hygiene, elevating caries risk by 1.5–2.5 times, but this consequence is disproportionately amplified in lower socioeconomic status (SES) populations due to confounding factors like high-sugar diets, limited fluoride exposure, infrequent professional cleanings, and poor access to preventive care—resulting in DMFT scores 20–50% higher in low-SES groups regardless of malocclusion severity alone. Cross-sectional studies in vulnerable cohorts (e.g., refu...

Benefit of orthodontic-surgical correction of a severe skeletal Class III

 # The benefit of orthodontic-surgical correction of a severe skeletal Class III is the ANB change. This change is best described as a combination of a surgically induced forward change in SNA and a: A. Surgically-induced forward change in SNB B. Vertical increase in posterior facial height C. Surgically-induced backward change in SNB D. Orthodontically-induced posterior dental rotation The correct answer is C. Surgically-induced backward change in SNB In severe skeletal Class III malocclusion, bimaxillary orthognathic surgery typically combines Le Fort I maxillary advancement (increasing SNA by 3–6 mm forward positioning) with bilateral sagittal split osteotomy (BSSO) mandibular setback (reducing SNB by 4–8 mm posteriorly), yielding a net ANB increase of 4–7° for Class I stability. Cephalometric studies confirm this dual skeletal adjustment as the primary mechanism for profile normalization and airway enhancement, with mandibular setback countering inherent prognathism without sol...

Significant adverse outcome of an uncorrected buccally-erupted maxillary canine

 # A significant adverse outcome of an uncorrected buccally-erupted maxillary canine is the potential for root resorption of the: A. Mandibular Canine B. Maxillary Central Incisor C. Maxillary Second Molar D. Maxillary First Premolar The correct answer is B. Maxillary Central Incisor Buccally-erupted maxillary canines, often ectopic in position, can migrate mesially during eruption, exerting direct pressure on the roots of adjacent anterior teeth—most notably the maxillary central incisor—leading to progressive external inflammatory root resorption (up to complete root loss in severe cases). Case reports and radiographic studies document this as a key sequela, with the canine's abnormal path causing odontoclastic activation via sustained physical contact, resulting in mobility, exfoliation, and functional/aesthetic deficits if uncorrected. While lateral incisors are more frequently affected overall in ectopic canines, central incisor involvement is a significant risk in buccal disp...

Occlusal feature most frequently associated with the development of abfraction lesions and non-carious cervical lesions

 # Which of the following occlusal features is most frequently associated with the development of abfraction lesions and non-carious cervical lesions? A. Class II Division 1 with deep overbite B. Severe Anterior Open Bite C. Bilateral Posterior Crossbite in CR and CO D. Non-working side occlusal interferences (mediotrusive contacts) The correct answer is D. Non-working side occlusal interferences (mediotrusive contacts) Non-working side occlusal interferences—contacts on the balancing (non-working) side during lateral mandibular excursions (mediotrusive movements)—generate eccentric tensile and compressive stresses that induce cervical tooth flexure, particularly in premolars and molars, promoting microfractures and enamel/dentin loss characteristic of abfraction lesions and NCCLs. Finite element models and clinical studies demonstrate these interferences elevate lesion risk by 2–4 times via sustained shearing forces (up to 50–100 N during excursions), with prevalence up to 70% in ...

Benefit of orthodontic treatment in reducing anterior mandibular crowding

 # The benefit of orthodontic treatment in reducing anterior mandibular crowding is often linked to the reduction of Gingival Index scores. This is primarily because proper alignment leads to: A. A greater volume of keratinized tissue around the incisors B. A reduction in plaque accumulation and gingival inflammation C. Increased vascularity and nutrient supply to the PDL D. Increased resistance to future recession and attachment loss The correct answer is B. A reduction in plaque accumulation and gingival inflammation Severe anterior mandibular crowding creates plaque-retentive interproximal and gingival crevices, elevating Gingival Index scores by 1–2 points on average due to chronic low-grade inflammation from bacterial accumulation. Orthodontic alignment (e.g., via archwire sequencing or IPR) enhances self-performed oral hygiene efficacy—reducing plaque index by 25–40% and GI by 0.5–1.0 within 6–12 months, as shown in randomized trials—by facilitating direct bristle/floss acces...

Key adverse consequence of uncorrected severe Class III malocclusion during adolescence

 # A key adverse consequence of uncorrected severe Class III malocclusion during adolescence is often an exacerbated negative self-perception primarily due to: A. The convex profile resulting from the mandibular retrusion B. Difficulty with mandibular posture and chewing C. Increased risk of dental trauma to the mandibular incisors D. The ‘dish face’ concave facial profile with prominent chin (prognathism) The correct answer is D. The ‘dish face’ concave facial profile with prominent chin (prognathism) Severe Class III malocclusion in adolescents often manifests as a concave "dish face" profile due to mandibular prognathism or relative maxillary retrusion, creating a prominent chin and retruded midface that deviates markedly from ethnic norms of facial harmony—leading to heightened self-consciousness, bullying, and diminished self-esteem as measured by tools like the Orthognathic Quality of Life Questionnaire (OQLQ), with scores 20–40% lower in untreated cases. Longitudinal ...

Malocclusion with highest risk for root resorption of the maxillary incisors

 # Which specific malocclusion, due to its inherent nature, presents the highest mechanical risk for palatal root resorption of the maxillary incisors during orthodontic alignment? A. Skeletal Class III with severe reverse overjet B. Deep Bite Class I with severe mandibular crowding C. Impacting a maxillary canine horizontally near the central incisor root D. Severe Class II Division 1 The correct answer is D. Severe Class II Division 1 In severe Class II Division 1 malocclusion, the proclined maxillary incisors necessitate substantial labial-to-lingual retraction during alignment (typically 4–7 mm bodily movement), which approximates the incisor roots to the lingual (palatal) cortical plate—reducing the root-to-cortex distance to <1 mm and imposing sustained compressive forces that elevate the risk of orthodontically induced inflammatory root resorption (OIIRR) on the palatal aspect by 1.5–2.5 times compared to Class I or III cases. Cephalometric and CBCT studies confirm this i...

Benefit of orthodontic treatment for patients with a pre-existing periodontal compromise

 # A key benefit of orthodontic treatment for patients with a pre-existing periodontal compromise (e.g., reduced but healthy periodontium) is: A. Elimination of all PDL forces in the compromised teeth B. Complete regeneration of lost alveolar bone and attachment C. Increased tooth mobility for better functional adaptation D. Optimization of axial loading to distribute occlusal forces more favorably The correct answer is D. Optimization of axial loading to distribute occlusal forces more favorably In patients with pre-existing periodontal compromise (e.g., reduced but stable attachment levels), orthodontic treatment aligns malpositioned teeth—such as flared or tipped incisors—to promote more vertical (axial) force transmission during occlusion, minimizing deleterious lateral or eccentric loads that exacerbate mobility, attachment loss, or alveolar stress in weakened areas. This biomechanical optimization, achieved via controlled intrusion and torque control with light forces (5–15 g...

Potential adverse consequence of rapid maxillary expansion (RME)

 # One potential adverse consequence of rapid maxillary expansion (RME) in a patient nearing skeletal maturity is an increase in: A. Anterior Bolton Ratio Discrepancy B. Apical Base Width C. Mandibular Plane Angle D. Palatal Vault Depth The correct answer is C. Mandibular Plane Angle In patients nearing skeletal maturity, the midpalatal suture is partially or fully interdigitated, reducing skeletal expansion efficacy and promoting dentoalveolar effects like buccal tipping and posterior molar extrusion (1–2 mm on average), which increases the mandibular plane angle (MPA) by 1–3° via clockwise mandibular rotation and bite opening. This vertical change exacerbates hyperdivergent tendencies, potentially worsening facial height and stability, as noted in cephalometric studies of late mixed/early permanent dentition cases. In contrast, apical base width (B) is the intended skeletal gain (though diminished); anterior Bolton discrepancy (A) is unrelated; and palatal vault depth (D) typical...

Relapse due to late anterior mandibular crowding

 # A key finding from long-term stability studies following orthodontic treatment is that late anterior mandibular crowding is often independent of the pre-treatment malocclusion. This relapse is primarily attributed to: A. A continued, anteriorly-directed component of natural craniofacial growth B. The patient's failure to wear a maxillary removable retainer C. Improper arch form used during the alignment phase D. A rebound effect from temporary root resorption during treatment The correct answer is A. A continued, anteriorly-directed component of natural craniofacial growth Long-term stability studies, including serial cephalometric analyses by Björk and Skieller, demonstrate that late mandibular anterior crowding (developing or worsening 5–10+ years post-treatment) arises from physiologic late mandibular growth—a forward (anteriorly directed) rotation and elongation of the chin relative to the stable incisor apices, which displaces the lower incisors lingually against lip and to...

Dental Health Component of Index of Orthodontic Treatment needs (DHC of IOTN)

 # From a public health perspective, the Dental Health Component (DHC) grade 4 of the IOTN classifies conditions where the adverse consequences are severe enough to require treatment for health reasons. Which Grade 4 sub-criterion is most directly linked to the risk of dental trauma? A. 4a: Increased overjet 6 mm to 9 mm with incompetent lips B. 4h: Extensive hypodontia requiring restorative dentistry C. 4i: Submerged deciduous teeth D. 4e: Severe skeletal discrepancy requiring surgery The correct answer is A. 4a: Increased overjet 6 mm to 9 mm with incompetent lips In the IOTN DHC, grade 4a specifically addresses increased overjet of 6–9 mm, which significantly elevates the risk of traumatic dental injuries to the maxillary incisors (relative risk ~2.8–4.0 compared to normal overjet <3 mm), as proclined incisors are more protrusive and vulnerable to impacts. Incompetent lips exacerbate this by failing to provide protective coverage, further increasing exposure—though standard I...

Correction of a severe anterior open bite in an adult through combined orthodontic and orthognathic surgery

 # Correction of a severe anterior open bite (greater or equal to 4 mm) in an adult through combined orthodontic and orthognathic surgery (e.g. Le Fort I impaction) primarily improves masticatory function by: A. Increasing the number of simultaneous bilateral posterior occlusal contacts B. Increasing the vertical dimension of occlusion C. Eliminating the need for tongue-thrust habit adaptation D. Preventing future TMJ derangement and pain The correct answer is A. Increasing the number of simultaneous bilateral posterior occlusal contacts Severe anterior open bite in adults often stems from vertical maxillary excess, leading to reduced or eccentric posterior occlusal contacts due to mandibular posturing or supraeruption, which impairs efficient bolus grinding and mixing during mastication (e.g., 20-40% lower chewing cycles for particle size reduction pre-treatment). Combined orthodontic-orthognathic intervention, such as Le Fort I impaction with mandibular autorotation, closes the ...

Adverse consequences of an uncorrected deep overbite (Class II Div 2)

 # Adverse consequences of an uncorrected deep overbite (Class II Div 2) are most directly related to the biomechanical factor of: A. Lack of freedom in centric relation to centric occlusion slide B. Inability to achieve canine-protected occlusion C. Increased horizontal components of force on posterior teeth D. Traumatic contact leading to gingival impingement or pathologic wear The correct answer is D. Traumatic contact leading to gingival impingement or pathologic wear In uncorrected Class II Division 2 malocclusion, the deep overbite (>5 mm typically) with retroclined maxillary central incisors positions the mandibular incisors to make direct, forceful contact with the palatal gingiva, mucosa, or incisal edges of the maxillary incisors during closure and excursions, imposing high compressive and shear stresses that biomechanically precipitate gingival recession (up to 2-3 mm loss), periodontal attachment breakdown, and localized enamel abrasion. Finite element analyses quant...

Impact of orthodontic treatment on TMD signs and symptoms based on high-quality systematic reviews

 # Which of the following is the most consistent finding regarding the impact of orthodontic treatment on TMD signs and symptoms based on high-quality systematic reviews? A. Correction of a deep overbite is the only proven method to prevent TMD in high-risk patients. B. Orthodontic treatment significantly decreases the risk and severity of TMD for all patients. C. Orthodontic treatment significantly increases the risk and severity of TMD due to prolonged appliance wear. D. Orthodontic treatment neither prevents nor causes TMD  The correct answer is D. Orthodontic treatment neither prevents nor causes TMD High-quality systematic reviews and meta-analyses, including those by Kim et al. (2002), Manfredini et al. (2016), and Jeong et al. (2024), consistently find no causal relationship between orthodontic treatment and TMD development or resolution, with pooled odds ratios near 1 (e.g., OR 0.75, 95% CI: 0.37–1.51; p=0.42) and qualitative syntheses showing only transient, mild sig...

The most crucial factor for long-term stability and prevention of relapse in the mandibular anterior segment after correction of severe crowding is:

 # The most crucial factor for long-term stability and prevention of relapse in the mandibular anterior segment after correction of severe crowding is: A. Interproximal reduction (IPR) sufficient to remove Bolton discrepancy B. Maintaining a well-fitted, bonded lingual retainer C. Normalizing the incisor-mandibular plane angle to 85-95 degrees D. Surgical normalization of the interdental papilla position The correct answer is B. Maintaining a well-fitted, bonded lingual retainer Severe mandibular anterior crowding relapse occurs in up to 70% of cases post-treatment due to soft tissue pressures, growth changes, and mesial drift, but long-term stability (e.g., <2 mm irregularity over 5+ years) is most reliably achieved with indefinite fixed retention via a well-fitted, bonded lingual retainer (e.g., 3x3 canine-to-canine design), which minimizes lower incisor proclination and intercanine width loss by 50-80% compared to removable options. Prospective and retrospective studies confi...

Predictor of increased idiopathic external apical root resorption (EARR) during fixed orthodontic treatment

 # Which pre-treatment occlusal factor is considered a significant, independent predictor of increased idiopathic external apical root resorption (EARR) during fixed orthodontic treatment? A. Deep, traumatic overbite with incisor contact B. Mild Class III Malocclusion with reverse overjet C. Severe Mandibular Anterior Crowding D. Pre Treatment history of TMD pain The correct answer is A. Deep, traumatic overbite with incisor contact Deep, traumatic overbite—where mandibular incisors impinge on maxillary incisor edges or palatal gingiva—necessitates corrective mechanics like incisor intrusion or torque adjustments during fixed orthodontic treatment, which exert sustained compressive forces on the periodontal ligament and cementum, elevating idiopathic EARR risk by 1.5–2.5 times compared to non-traumatic deep bites (p < 0.05). Multivariate analyses confirm this as an independent pre-treatment predictor, distinct from treatment duration or extractions, due to the heightened biomech...

The improvement in masticatory function following the correction of a posterior unilateral crossbite is best attributed to the restoration of:

 # The improvement in masticatory function following the correction of a posterior unilateral crossbite is best attributed to the restoration of: A. Reduced muscle hyperactivity in the temporalis muscle B. Elimination of a functional midline deviation C. Bilateral, simultaneous grinding and mixing function D. Ideal anterior guidance and disclusion The correct answer is C. Bilateral, simultaneous grinding and mixing function Posterior unilateral crossbite induces a functional mandibular shift toward the crossbite side in centric occlusion, resulting in asymmetric bolus manipulation, preferential unilateral chewing, and reduced efficiency in comminution (grinding) and food mixing. Orthodontic or orthopedic correction (e.g., via expansion or asymmetric mechanics) repositions the mandible to eliminate this shift, reestablishing symmetric occlusal contacts and enabling bilateral, coordinated mandibular excursions for optimal masticatory performance—as evidenced by improved electromyogr...

Impact of comprehensive orthodontic treatment on adolescents using Health-Related Quality of Life (HRQoL)

 # Improvement in which domain is typically the most significant and consistent finding in longitudinal studies assessing the impact of comprehensive orthodontic treatment on adolescents using Health-Related Quality of Life (HRQoL) instruments? A. Temporomandibular Joint (TMJ) Symptom Reduction B. Periodontal Health and Plaque Index Scores C. Masticatory Function and Dietary Habits D. Psycho-social Well-being and Self-esteem The correct answer is: D. Psycho-social Well-being and Self-esteem Longitudinal studies and meta-analyses of orthodontic treatment in adolescents consistently report the most significant and robust improvements in psycho-social domains of HRQoL, including emotional well-being and social well-being, with standardized mean differences of -0.61 (95% CI: -0.80 to -0.41) and -0.62 (95% CI: -0.82 to -0.43), respectively—outperforming functional or physical domains. These gains stem from enhanced aesthetics, reduced self-consciousness, and improved social interaction...

Correcting severe mandibular anterior crowding primarily benefits periodontal health by allowing for:

 # Correcting severe mandibular anterior crowding primarily benefits periodontal health by allowing for: A. Normalization of the mandibular incisor-mandibular plane angle B. Reduction of excessive occlusal forces on incisors C. Improved patient access for plaque control and effective oral hygiene D. Increased bone density in the anterior alveolar process The correct answer is C. Improved patient access for plaque control and effective oral hygiene Severe mandibular anterior crowding creates interproximal and gingival crevices that trap plaque and food debris, promoting gingival inflammation, increased probing depths, and higher risk of periodontal attachment loss. Orthodontic correction aligns teeth, facilitating thorough brushing, flossing, and professional cleanings—leading to significant reductions in plaque index (e.g., 20-30% improvement post-treatment) and gingival bleeding, as shown in prospective studies. While normalization of incisor-mandibular plane angle (A) aids stabil...

Primary benefit of early orthodontic intervention for severely proclined maxillary incisors

 # A primary benefit of early orthodontic intervention for severely proclined maxillary incisors is the reduction of trauma risk. The most definitive evidence-based recommendation for this treatment is specifically for children with an overjet greater than: A. Overjet greater or equal to 8 mm B. Overjet greater or equal to 3 mm C. Overjet greater or equal to  4.5 mm with lip incompetence D. Overjet greater or equal to 6 mm The correct answer is D. Overjet greater or equal to 6 mm Evidence-based guidelines, such as the UK's Index of Orthodontic Treatment Need (IOTN) Dental Health Component, classify an overjet ≥6 mm (grade 4: great need) as a clear indication for orthodontic intervention, primarily due to the markedly elevated risk of traumatic dental injuries to proclined maxillary incisors—up to fourfold higher compared to normal overjet. Meta-analyses confirm this threshold aligns with a relative risk of 3.37 (95% CI: 1.81–6.27) for trauma in children with overjet ≥6 mm, jus...

Which dentofacial morphology is generally considered the highest risk factor for the development or exacerbation of Obstructive Sleep Apnea (OSA) in adults?

 # Which dentofacial morphology is generally considered the highest risk factor for the development or exacerbation of Obstructive Sleep Apnea (OSA) in adults? A. Deep Bite Class II Division 2 with an average mandibular plane angle B. High Angle Class II with marked Mandibular Retrognathia C. High Angle Class III with Anterior Crossbite D. Low Angle Class I with severe dental crowding B. High Angle Class II with marked Mandibular Retrognathia High-angle Class II malocclusion, characterized by a steep mandibular plane angle (indicating a vertical growth pattern) and significant mandibular retrognathia (receded lower jaw), is a major anatomical risk factor for OSA in adults. This morphology reduces pharyngeal airway space by positioning the hyoid bone and tongue base posteriorly, promoting airway collapse during sleep—exacerbated by the dolichofacial pattern's narrower transverse dimensions. Studies confirm this combination correlates with decreased upper airway volume and higher OS...

A functional lateral shift of the mandible into maximum intercuspation is most likely to be associated with which long-term consequence if left uncorrected during the active growth period?

 # A functional lateral shift of the mandible into maximum intercuspation is most likely to be associated with which long-term consequence if left uncorrected during the active growth period? A. Increased risk of External Apical Root Resorption (EARR) B. Pathologic Attrition on the non-shifted side C. Anterior Open Bite Development D. Skeletal Asymmetry The correct answer is  D. Skeletal Asymmetry A functional lateral shift of the mandible—often due to unilateral posterior crossbite—forces the jaw to deviate laterally into maximum intercuspation to avoid occlusal interferences. During active growth, this chronic deviation alters condylar loading and remodeling, promoting asymmetric mandibular growth (e.g., longer ramus or body on the shifted side) and potential facial skeletal discrepancies, such as chin deviation or canting. Early correction is crucial, as these changes become increasingly permanent post-growth. This contrasts with the other options: EARR is more tied to ort...

Malocclusion affecting the production of sibilant sounds

 # The production of sibilant sounds (e.g., 's', 'z') is most commonly affected by which two concurrent malocclusion features due to uncontrolled air escape and altered tongue positioning? A. Unilateral Posterior Crossbite and Midline Discrepancy B. Severe Mandibular Crowding and Deep Overbite C. Excessive Overjet and Anterior Open Bite D. Class III Malocclusion and Edge-to-Edge Incisors The correct answer is:  C. Excessive Overjet and Anterior Open Bite Sibilant sounds like 's' and 'z' rely on precise airflow through a narrow tongue-to-palate groove, and disruptions from excessive overjet (protruding upper incisors) alter tongue positioning, while anterior open bite allows uncontrolled air escape through the anterior gap, often causing lisps or distortions. Studies confirm this combination's strong impact on sibilants, unlike the other options, which less directly affect anterior airflow or tongue placement for these sounds.

Severe, localized pathologic attrition on the palatal surfaces of maxillary incisors and the incisal edges of mandibular incisors is most commonly pathognomonic of which specific malocclusion?

 # Severe, localized pathologic attrition on the palatal surfaces of maxillary incisors and the incisal edges of mandibular incisors is most commonly pathognomonic of which specific malocclusion? A. Severe Anterior Open Bite B. Class II Division 2 Malocclusion (Deep Bite) C. Unilateral Posterior Crossbite with functional shift D. Class I Malocclusion with severe posterior crowding The correct answer is:  B. Class II Division 2 Malocclusion (Deep Bite) This wear pattern—severe, localized pathologic attrition on the palatal surfaces of the maxillary incisors and the incisal edges of the mandibular incisors—is pathognomonic for Class II Division 2 malocclusion, which features retroclined maxillary central incisors and a deep overbite. In this condition, the mandibular incisors contact the lingual (palatal) aspects of the maxillary incisors during occlusion, leading to friction and progressive enamel loss at these sites over time. This contrasts with the other options: anterior o...

Accommodation Options for Delegates Attending the 16th International Conference of ODOAN, Dharan, Nepal

Our Conference venue is White Elegance Palace, Dharan.   Stay comfortably close to the venue! Here are our recommended hotels for your convenience: 1.  Hotel Brick Address:  Sainik Chowk, Dharan, Sunsari, Nepal Phone:  +977 9769703533 Distance:  1 Kilometer CLICK HERE TO VIEW REVIEWS ON GOOGLE 2.  Hotel Meriken Address:  Dharan-15, Ramlaxman Marga, Dharan, Sunsari, Nepal Phone:  +977 9761003570 Distance:  2.6 Kilometer CLICK HERE TO VIEW REVIEWS ON GOOGLE 3. Hotel Star Purwi Address:  Chatara Line, Dharan, Sunsari, Nepal Phone:  +977 9817302498 / +977 9840070025 Distance:  750 meters CLICK HERE TO VIEW REVIEWS ON GOOGLE Non AC Single @ Rs. 1600 AC Twin Double @ Rs. 2500 AC Deluxe Tripe Sharing @ Rs. 2500 AC Deluxe Master Bedrooms @ Rs. 2200 4.  New Dreamland Hotel & Lodge Address:  Dhankute Road, Dharan, Sunsari, Nepal Phone:  +977 25 525024, +977 25 575024, +977 25 575300 Distance:  1 Kilometer CLICK HE...

The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and the Index of Orthodontic Treatment Need (IOTN) are both used to assess treatment need. Which component of the IOTN is most directly correlated with the patient-reported concerns measured by the PIDAQ?

 The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and the Index of Orthodontic Treatment Need (IOTN) are both used to assess treatment need. Which component of the IOTN is most directly correlated with the patient-reported concerns measured by the PIDAQ? A. The Treatment Complexity Index (TCI) B. The Aesthetic Component (AC) C. The Dental Health Component (DHC) D. The Peer Assessment Rating (PAR) Index  The correct answer is B. The Aesthetic Component (AC) The PIDAQ assesses patient-reported psychosocial impacts (e.g., psychological, social, and aesthetic self-consciousness) stemming from perceived dental aesthetics, making it a subjective, condition-specific OHRQoL tool. The IOTN's Aesthetic Component (AC) directly evaluates subjective aesthetic impairment via a 10-point visual scale of anterior teeth appearance (clinician-rated but perception-based), aligning closely with PIDAQ's focus on self-perceived concerns. Validation studies consistently use AC for ...

Based on current, high-level evidence, which occlusal feature has demonstrated the strongest, albeit weak, statistical association with an increased prevalence of pain-related Temporomandibular Disorders (TMD)?

 # Based on current, high-level evidence, which occlusal feature has demonstrated the strongest, albeit weak, statistical association with an increased prevalence of pain-related Temporomandibular Disorders (TMD)? A. Anterior Open Bite B. Class II Division 2 Malocclusion C. Overjet greater or equal to 6 mm D. Posterior Unilateral Crossbite The correct answer is  D. Posterior Unilateral Crossbite High-level evidence from systematic reviews, such as the 2025 review by Alghamdi et al. in Frontiers in Neurology (analyzing 17 studies on children/adolescents), identifies posterior unilateral crossbite as having the strongest association with pain-related TMD signs/symptoms, including TMJ/muscle pain and tenderness. Pooled data show odds ratios (ORs) of 2.25–5.74 (95% CIs: 1.15–4.43 to 1.18–27.85; p<0.05 across studies like Pereira et al. 2009 and Perrotta et al. 2018), indicating a 2–6-fold increased risk, though with low GRADE certainty due to cross-sectional designs and hetero...

The primary mechanism by which severe mandibular incisor crowding is hypothesized to independently increase the risk of localized periodontal breakdown, beyond confounding factors like poor hygiene, is:

The primary mechanism by which severe mandibular incisor crowding is hypothesized to independently increase the risk of localized periodontal breakdown, beyond confounding factors like poor hygiene, is: A. Increased horizontal force application on the periodontium B. Increased localized tooth mobility secondary to reduced bone support C. Reduced access for optimal plaque control by the patient D. Development of fenestrations and dehiscences due to tooth displacement The correct answer is  D. Development of fenestrations and dehiscences due to tooth displacement Severe mandibular incisor crowding causes teeth to displace or rotate within the alveolar housing, violating bone constraints and leading to cortical plate resorption. This results in fenestrations (narrow bone defects exposing root surfaces) and dehiscences (wider marginal defects causing gingival recession and reduced bone support), increasing localized periodontal breakdown risk independently of plaque accumulation or hy...