Prometric Exam Questions for Orthodontics Specialists 2026: 20 MCQs with Answers on Growth and Development, Cephalometrics, Malocclusion Classification, Anchorage, Biomechanics, Functional Appliances, Extraction Decisions, Retention and Orthognathic Surgery

The specialist orthodontics paper (ORD5211 at DHA, and the equivalent SCFHS, QCHP and NHRA papers) is 100 to 150 single-best-answer questions in up to three hours with a pass mark of about 60%. Candidates with an MDS, MS, MOrth, a three-year orthodontic residency or an Arab Board sit it after the authority confirms the specialist title. The paper is clinical and diagnostic: classify the malocclusion, read the cephalogram, decide the timing and the appliance, and manage the complications. Orthodontics is the Gulf's largest specialist dental market, so demand is high and the exam is competitive. The licensing route is in the specialist dentist guide.

Growth, development and diagnosis

Question 1

A 9-year-old has a 3 mm maxillary midline diastema with unerupted permanent canines on radiograph. The most appropriate management is:

1. Immediate closure with fixed appliances
2. Monitor, because a diastema in the "ugly duckling" stage usually closes spontaneously as the permanent canines erupt; intervene only if it persists after canine eruption, with assessment for a low frenum, supernumerary (mesiodens) or missing lateral incisors
3. Frenectomy now
4. Composite build-ups

Answer: B. Early frenectomy before canine eruption can leave scar tissue that prevents closure.

Question 2

A patient's maxillary first molar mesiobuccal cusp occludes in the buccal groove of the mandibular first molar, but the lower incisors occlude behind the cingulum plateau of the upper incisors with an overjet of 6 mm. The classification is:

1. Angle Class II division 1
2. Angle Class I molar relationship with a British Standards Institute Class II division 1 incisor relationship
3. Class III
4. Class II division 2

Answer: B. Angle classification describes the molars; incisor classification describes the incisors; the two do not always agree, and treatment planning is based on both plus the skeletal pattern.

Question 3

Cephalometric analysis shows SNA 82°, SNB 74°, ANB 8°, and a maxillary-mandibular planes angle of 36°. The skeletal pattern is:

1. Class III with a low angle
2. Skeletal Class II due to mandibular retrognathia with increased vertical proportions (high angle), which makes mandibular advancement or growth modification the logical approach and makes extrusive mechanics and Class II elastics risky because they open the bite further
3. Class I
4. Maxillary excess only

Answer: B. Normal values are about SNA 82°, SNB 80°, ANB 2 to 4° and MMPA 27°; a reduced SNB with normal SNA locates the discrepancy in the mandible.

Question 4

Mixed dentition space analysis in a 9-year-old predicts an arch length deficiency of 10 mm per arch with a Class I skeletal pattern and well-aligned incisors. The traditional interceptive approach is:

1. Extraction of all first permanent molars
2. Serial extraction (deciduous canines, then first deciduous molars, then first premolars) in carefully selected severe crowding cases, with later fixed appliance alignment, recognising that it is used less now and never with a Class II or III skeletal pattern, deep bite or spacing
3. Rapid maxillary expansion in all cases
4. No treatment until all permanent teeth erupt

Answer: B. Moyers and Tanaka-Johnston analyses predict the unerupted canine and premolar widths from the lower incisors; the leeway space (about 2.5 mm per side in the lower arch) is also relevant.

Interceptive and early treatment

Question 5

A 10-year-old has a unilateral posterior crossbite with a mandibular displacement on closing and a midline shift. The recommended management is:

1. Wait until age 15
2. Early correction with maxillary expansion (a quad helix or rapid maxillary expander) to eliminate the displacement and allow symmetrical growth, because untreated functional crossbites can produce asymmetric mandibular growth and TMJ symptoms
3. Extraction of the upper premolars
4. Lower arch expansion only

Answer: B. Rapid maxillary expansion works best before fusion of the mid-palatal suture; in adults surgically assisted or miniscrew-assisted expansion is needed.

Question 6

A 10-year-old's maxillary canine cannot be palpated in the buccal sulcus and radiographs show the canine crown overlapping the lateral incisor root (sector 3). The interceptive measure with the best evidence is:

1. Observation until age 14
2. Extraction of the deciduous canine (with space maintenance or expansion if the arch is crowded), which normalises the eruption path of a palatally displaced canine in a majority of cases when done at 10 to 13 years
3. Immediate surgical exposure
4. Extraction of the lateral incisor

Answer: B. Canines not palpable by age 10 to 11 need radiographic localisation (parallax or CBCT); untreated palatal canines can resorb the lateral incisor roots.

Question 7

A 12-year-old girl with a Class II division 1 malocclusion, overjet 9 mm, retrusive mandible, average vertical proportions and competent lips is in the pubertal growth spurt. The treatment with the best evidence at this stage is:

1. Wait until growth is complete, then orthognathic surgery
2. A functional appliance (for example a Twin Block) to posture the mandible forward during peak growth, followed by fixed appliances for detailing; starting treatment earlier (phase 1 at 8 to 9) does not improve final outcomes and lengthens treatment
3. Headgear only
4. Extraction of the lower premolars

Answer: B. Functional appliances produce mostly dentoalveolar change with a small, variable skeletal effect; they also reduce incisor trauma risk from the large overjet.

Question 8

An 8-year-old has a Class III malocclusion with maxillary retrusion, an anterior crossbite and a mild skeletal discrepancy. The early treatment most likely to help is:

1. A chin cup alone
2. Maxillary protraction with a facemask (reverse-pull headgear), often combined with rapid maxillary expansion, before age 10 when the circummaxillary sutures respond; bone-anchored protraction is an option in older children
3. Lower incisor extraction
4. Class III elastics with fixed appliances now

Answer: B. Mandibular prognathism continues to grow into the late teens, so severe Class III cases are often camouflaged or treated surgically after growth; early protraction gives the best chance of avoiding surgery in maxillary-deficient cases.

Biomechanics and anchorage

Question 9

During space closure after upper premolar extractions, the clinician wants to retract the anterior teeth without forward movement of the molars. This describes:

1. Minimum anchorage
2. Maximum (Group A) anchorage, achieved with transpalatal arches, headgear, Nance buttons or, most predictably, temporary anchorage devices (miniscrews) that give absolute anchorage
3. Reciprocal anchorage
4. Intermaxillary anchorage only

Answer: B. Anchorage is the resistance to unwanted tooth movement; Class II elastics reinforce upper anchorage at the cost of lower incisor proclination.

Question 10

A force applied at the bracket of an incisor produces tipping. To achieve bodily (translational) movement, the clinician must:

1. Increase the force magnitude
2. Apply a counter-moment at the bracket so that the moment-to-force ratio is about 10:1, moving the centre of rotation towards infinity; ratios of about 7:1 produce controlled tipping and above 12:1 root movement
3. Use a round wire
4. Reduce the force to zero

Answer: B. The centre of resistance of a single-rooted tooth lies about one third to one half of the way down the root; force through the bracket is always offset from it.

Question 11

Which force level is recommended for tipping a single-rooted tooth, and which for intrusion of incisors?

1. Tipping 300 g, intrusion 200 g per tooth
2. Tipping about 35 to 60 g, intrusion about 10 to 20 g per tooth, because light continuous forces produce frontal resorption rather than undermining (hyalinisation) and reduce root resorption
3. Any force works equally
4. Tipping 500 g

Answer: B. Translation needs about 70 to 120 g and root uprighting 50 to 100 g; nickel-titanium archwires deliver light continuous forces in the aligning phase.

Question 12

A patient has mild to moderate crowding, a Class I skeletal pattern, proclined upper incisors with lips that are already protrusive, and a good profile that the patient does not want changed. The best approach is:

1. Non-extraction treatment with arch expansion and proclination
2. An extraction-based plan is more appropriate because non-extraction treatment would further procline the incisors and protrude the lips; extraction decisions weigh crowding, incisor position, profile, vertical pattern and anchorage, and are not formulaic
3. Interproximal reduction of 10 mm
4. Distalisation with headgear in an adult

Answer: B. Each millimetre of incisor retraction changes lip position by roughly two thirds of a millimetre; the extraction versus non-extraction decision is heavily tested.

Appliances and complications

Question 13

Which malocclusion is least suited to treatment with clear aligners alone?

1. Mild crowding with good alignment of the roots
2. A severe deep bite requiring significant incisor intrusion and molar extrusion, large rotations of rounded teeth (canines and premolars), significant extrusion, and major anteroposterior correction without auxiliaries
3. Mild spacing
4. Relapse of lower incisor alignment

Answer: B. Aligners are predictable for tipping and mild crowding, less predictable for bodily movement, extrusion and rotations; attachments and elastics extend their range. Gulf authorities require aligner therapy to be prescribed and supervised by a licensed dentist.

Question 14

After 18 months of fixed appliance treatment, a periapical radiograph shows blunting and 3 mm of apical root shortening of the upper central incisors. The appropriate response is:

1. Continue unchanged; resorption is cosmetic
2. Pause active forces for 2 to 3 months (passive archwire), reassess the risk-benefit of remaining movements, prioritise finishing, inform the patient and document; risk factors include previous trauma, pipette-shaped or short roots, prolonged treatment, intrusion and heavy forces
3. Extract the incisors
4. Increase forces to finish faster

Answer: B. Some apical resorption occurs in most patients; severe resorption (over 4 mm or a third of root length) affects a small minority and progression stops once appliances are removed.

Question 15

At the debond appointment, white spot lesions are visible around the bracket footprints. The management and the prevention that should have been in place are:

1. Immediate composite veneers
2. Allow natural remineralisation with fluoride toothpaste for a few months (avoiding high-concentration fluoride immediately, which can arrest lesions in an opaque state), then consider resin infiltration or microabrasion for persistent lesions; prevention is oral hygiene reinforcement, fluoride mouthrinse, fluoride-releasing cements and sealants, and stopping treatment in persistently poor hygiene
3. Bleaching
4. Crowns

Answer: B. Demineralisation can begin within four weeks around brackets; hygiene assessment before and during treatment is a licensing-level standard of care.

Question 16

A 25-year-old is about to start fixed appliance treatment and has 6 mm pocketing with bleeding around the lower incisors. The correct sequence is:

1. Start orthodontics and treat the periodontium afterwards
2. Periodontal treatment and demonstrated stability (no active disease, good plaque control) before appliance placement, with light forces, longer intervals and periodontal maintenance during treatment, because moving teeth through inflamed periodontium accelerates bone loss
3. Extract the lower incisors
4. Aligners instead, which do not affect the periodontium

Answer: B. Reduced but healthy periodontium can be treated orthodontically; the centre of resistance moves apically, so the moment-to-force ratios change.

Retention, impacted teeth and surgery

Question 17

Which orthodontic correction is most prone to relapse and therefore needs prolonged or permanent retention?

1. Correction of a posterior crossbite with good overbite
2. Lower incisor alignment, closed midline diastemas, rotations, expanded intercanine width and corrected anterior open bites, for which bonded retainers or indefinite night-time removable retainers are advised
3. Correction of an increased overjet with lip competence achieved
4. Space closure in extraction cases

Answer: B. Late lower incisor crowding occurs in untreated and treated patients alike; patients are told that retention is lifelong if they want alignment to stay.

Question 18

A 15-year-old has a palatally impacted upper canine with adequate space in the arch and a favourable position (overlapping less than half the lateral incisor root, angle under 30° to the midline). The treatment of choice is:

1. Extraction of the canine and prosthetic replacement
2. Surgical exposure (closed technique with a bonded attachment and gold chain, or open exposure) and orthodontic alignment with fixed appliances, with CBCT to exclude resorption of adjacent roots
3. Autotransplantation as first choice
4. Leave in situ with no follow-up

Answer: B. Unfavourable canines (high, horizontal, close to the midline, with resorption) may be removed, transplanted or left under radiographic review; leaving a tooth in situ requires monitoring for cyst formation.

Question 19

A 20-year-old has a severe skeletal Class III (ANB −5°), a reverse overjet of 6 mm and a concave profile that concerns them. The appropriate plan is:

1. Orthodontic camouflage with upper premolar extractions
2. Combined orthodontic and orthognathic treatment: pre-surgical decompensation of the incisors (which initially worsens the reverse overjet), then mandibular setback and/or maxillary advancement (bimaxillary surgery), then post-surgical finishing, in a joint clinic with a maxillofacial surgeon
3. Facemask therapy
4. Chin cup for two years

Answer: B. Camouflage is reserved for mild discrepancies with acceptable profiles; decompensation is the concept most tested in surgical cases.

Question 20

An adult patient wants orthodontic treatment but has clicking of the temporomandibular joint without pain or locking. The appropriate approach is:

1. Refuse treatment until the click resolves
2. Document the TMJ findings before treatment, explain that orthodontics neither reliably causes nor cures temporomandibular disorders, proceed with treatment while monitoring, and manage any pain conservatively (education, soft diet, splint, physiotherapy)
3. Promise that orthodontics will cure the click
4. Equilibrate the occlusion first

Answer: B. Painless clicking is common and benign; the evidence does not support orthodontics or occlusal adjustment as TMD treatments.

How to practise

• Learn the numbers: cephalometric norms, force levels, moment-to-force ratios, space analysis, timing windows for interceptive treatment.
• Practise classification from photographs and radiographs: the paper is image-rich.
• Know the decisions that are tested: extraction versus non-extraction, functional appliance timing, canine management, camouflage versus surgery, retention.
• Practise under time in the Orthodontics bank with the error-log method.

Related sets: general dentistry questions and paediatric dentistry questions. Other specialist dental banks: Prosthodontics and Restorative Dentistry. The image-practice plan is in dental exam preparation.

Frequently asked questions

How many questions are in the Prometric orthodontics specialist exam?

Typically 100 to 150 single-best-answer MCQs in up to three hours, with a pass mark of about 60%, varying by authority.

Which orthodontics topics come up most?

Diagnosis and cephalometrics, interceptive treatment, Class II and Class III treatment timing, anchorage and biomechanics, extraction decisions, retention and complications such as root resorption.

Does the exam include clear aligners?

Yes, at the level of case selection, limitations and supervision requirements.

Can a general dentist with an orthodontics diploma get the specialist title?

Usually not. Authorities require a recognised full-time postgraduate orthodontic degree or residency of about three years; short courses qualify a general dentist to perform limited orthodontics only.

Are these real exam questions?

No. They are original practice questions written to the published blueprint. Real exam content is confidential.