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Key Facts: Iran Dental Specialty Board - Orthodontics Exam

100

Written multiple-choice questions on the national dental specialty board examination

Council for Dental and Specialized Education / Sanjesh Pezeshki

120 min

Total allotted duration for the written specialty board examination session

Sanjesh Pezeshki examination regulations

70%

Minimum qualifying score (70/100) required to advance to the clinical and oral board phase

Ministry of Health and Medical Education board guidelines

Negative marking score penalty: incorrect answers do not deduct points

Sanjesh Pezeshki dental specialty examination rules

Annual (Shahrivar)

Examination schedule, held once per year in late summer in Tehran

Sanjesh Pezeshki national specialty examination calendar

The Iranian Orthodontics Dental Specialty Board is a high-stakes national milestone consisting of a 100-question, 100-minute written MCQ exam (passing threshold 70%, no negative marking) followed by clinical case portfolio defense and oral examination, certifying specialists for orthodontic practice and academic faculty appointment across Iran.

Sample Iran Dental Specialty Board - Orthodontics Practice Questions

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1According to Melvin Moss's Functional Matrix Hypothesis, which of the following skeletal structures represents a skeletal unit controlled primarily by a capsular functional matrix?

A.The neurocranial vault expanding in response to brain volume and cerebrospinal fluid expansion

B.The coronoid process of the mandible developing in response to temporalis muscle contraction

C.The gonial angle of the mandible remodeling in response to masseter and medial pterygoid muscle activity

D.The alveolar process of the maxilla forming in direct response to the functional eruption of teeth

Explanation: Under Moss's Functional Matrix Hypothesis, capsular functional matrices consist of volume-expanding masses within neurocranial or orofacial capsules (such as the brain and cerebrospinal fluid or the functioning nasopharyngeal space) that produce passive translational expansion of skeletal capsules. Periosteal functional matrices, in contrast, comprise muscles, teeth, and localized soft tissues that act directly upon specific microskeletal units (such as the coronoid process responding to the temporalis muscle, or the alveolar process responding to dentition).

2In Alexandre Petrovic's cybernetic model of facial growth, which neuromuscular structure serves as the primary peripheral comparator and actuator that adjusts condylar cartilage proliferation?

A.The sphenomandibular ligament acting via tension mechanoreceptors

B.The lateral pterygoid muscle and retrodiscal pad modulating condylar posture

C.The buccinator mechanism redirecting buccal alveolar bone drift

D.The anterior belly of the digastric muscle depressing the symphysis

Explanation: Petrovic's cybernetic model conceptualizes condylar growth as secondary adaptive remodeling guided by a neuromuscular servomechanism. The lateral pterygoid muscle, together with vascular hyperemia of the retrodiscal pad, acts as the primary comparator and actuator; its contractile activity postures the condyle relative to the glenoid fossa in response to occlusal feedback, stimulating chondrogenesis in the prechondroblastic zone of condylar cartilage.

3Which craniofacial synchondrosis represents the principal postnatal growth center of the cranial base and remains patent until late adolescence?

A.Intersphenoid synchondrosis

B.Spheno-ethmoidal synchondrosis

C.Spheno-occipital synchondrosis

D.Intra-occipital synchondrosis

Explanation: The spheno-occipital synchondrosis is the principal postnatal cartilaginous growth center of the cranial base, continuing endochondral ossification and anteroposterior lengthening throughout puberty until it fuses between approximately 15 and 18 years of age. Other cranial base synchondroses ossify far earlier: the intersphenoid fuses at or before birth, the intra-occipital synchondroses fuse in early childhood, and the spheno-ethmoidal synchondrosis closes around 6 to 7 years of age.

4At what approximate chronological age does the spheno-ethmoidal synchondrosis typically complete its endochondral ossification and cease contributing to anterior cranial base lengthening?

A.At birth

B.Between 1 and 2 years of age

C.Between 15 and 18 years of age

D.Between 6 and 7 years of age

Explanation: The spheno-ethmoidal synchondrosis completes endochondral ossification and functional closure between 6 and 7 years of age. After this milestone, anterior cranial base length (sella to nasion) increases predominantly through surface remodeling and apposition on the outer table of the frontal bone at nasion, while the spheno-occipital synchondrosis remains active into adolescence.

5In the postnatal growth of the nasomaxillary complex, what mechanism accounts for primary displacement of the maxilla in an anterior and inferior direction?

A.Bone deposition at posterior maxillary sutures pushing the maxilla forward against the cranial base

B.Passive forward translation of the maxilla driven solely by forward elongation of the anterior cranial base

C.Direct periosteal bone resorption on the posterior surface of the maxillary tuberosity

D.Active pull of the facial expression muscles inserting into the anterior nasal spine

Explanation: Primary displacement occurs when an expanding bone's own remodeling and enlargement at its boundaries displaces the bone away from adjoining structures. In the nasomaxillary complex, active bone apposition at the circummaxillary sutures and the posterior surface of the maxillary tuberosity pushes the maxilla forward and downward against the cranial base and pterygoid plates. Secondary displacement, in contrast, is the passive forward movement of the maxilla produced by growth of the cranial base itself.

6During normal postnatal mandibular remodeling, which pattern of surface apposition and resorption occurs on the mandibular ramus to accommodate erupting permanent molars?

A.Bone deposition on the anterior border and resorption on the posterior border

B.Bone resorption on the anterior border and deposition on the posterior border

C.Bone deposition across both anterior and posterior borders equally

D.Bone resorption across both anterior and posterior borders equally

Explanation: To accommodate erupting permanent molars and permit backward elongation of the dental arch, the anterior border of the mandibular ramus undergoes continuous osteoclastic bone resorption while the posterior border exhibits bone apposition. This progressive posterior relocation of the ramus converts former ramal bone into the posterior alveolar ridge and lengthens the mandibular body.

7How does the histological architecture of mandibular condylar cartilage fundamentally differ from that of a primary long-bone epiphyseal growth plate?

A.Condylar cartilage possesses highly ordered parallel columns of proliferating chondrocytes

B.Condylar cartilage is covered by hyaline cartilage on its outermost articulating surface

C.Condylar cartilage is capped by a fibrous connective tissue layer containing multidirectional prechondroblasts

D.Condylar cartilage arises directly from primary neuroectodermal endochondral pre-skeletal blastema

Explanation: Mandibular condylar cartilage is a secondary cartilage that develops independently from the primary embryonic cartilaginous skeleton. Histologically, its articular surface is covered by a dense fibrous connective tissue layer rather than hyaline cartilage, and its underlying proliferative prechondroblastic zone lacks the organized, parallel columnar cellular architecture characteristic of epiphyseal growth plates. This allows condylar cartilage to respond adaptively to regional biomechanical stimuli.

8According to Richard Scammon's curves of systemic tissue growth, which tissue type exhibits peak growth exceeding 200% of adult size around puberty before involution?

A.Neural tissue

B.General somatic tissue

C.Genital tissue

D.Lymphoid tissue

Explanation: Scammon's curves of systemic growth categorize human tissues into four distinct patterns: neural, somatic (general), genital, and lymphoid. Lymphoid tissue (including adenoids, tonsils, and lymph nodes) proliferates rapidly during childhood, reaching a peak of approximately 200% of adult dimensions around 10 to 12 years of age before undergoing physiological involution and atrophy under the influence of pubertal sex hormones.

9In what chronological sequence do the three dimensional planes of craniofacial growth typically complete their active development?

A.Transverse growth completes first, followed by anteroposterior (sagittal), and vertical completes last

B.Vertical growth completes first, followed by transverse, and anteroposterior completes last

C.Anteroposterior growth completes first, followed by vertical, and transverse completes last

D.Transverse and vertical growth complete simultaneously, followed by anteroposterior

Explanation: Craniofacial growth ceases in a well-established chronological sequence across spatial planes: transverse growth (e.g., palatal vault expansion, intercanine width) finishes first, usually before the adolescent growth spurt; anteroposterior (sagittal) growth continues through puberty and ceases shortly after; and vertical growth (e.g., lower anterior facial height, ramus height, dentoalveolar vertical eruption) continues the longest, extending well into late adolescence and early adulthood.

10In the Cervical Vertebral Maturation (CVM) method described by Baccetti et al., which stage is characterized by concavity at the inferior borders of C2 and C3 with trapezoid vertebral bodies, marking the onset of the peak mandibular growth spurt?

A.CVS 1 (Cervical Stage 1)

B.CVS 3 (Cervical Stage 3)

C.CVS 5 (Cervical Stage 5)

D.CVS 6 (Cervical Stage 6)

Explanation: In the CVM staging system, Cervical Stage 3 (CS3) marks the acceleration phase where the peak in mandibular growth will occur during the subsequent year. At CS3, distinct concavities are visible at the inferior borders of both C2 and C3, while the bodies of C3 and C4 remain trapezoid or rectangular horizontal. By CS4, concavities are present at C2, C3, and C4, and peak velocity is reached or just completed.

About the Iran Dental Specialty Board - Orthodontics Exam

The Iranian Dental Specialty Board Examination in Orthodontics (آزمون دانشنامه تخصصی دندانپزشکی - ارتودانتیکس), commonly known as the Orthodontic National Board (بورد تخصصی ارتودانتیکس), is the prestigious credentialing examination administered by the National Center for Health Assessment (Sanjesh Pezeshki) under the authority of the Ministry of Health and Medical Education (MOHME) and the Council for Dental and Specialized Education. Successful completion awards candidates the National Specialty Board Certificate (Danishnameh Takhassosi), the mandatory prerequisite for holding academic faculty positions at Iranian dental schools, serving as residency program directors, and maintaining peer-recognized specialty standing across the country. The examination tests mastery across six core blueprint domains: Craniofacial Growth & Development & Etiology of Malocclusion (~20%), Orthodontic Diagnosis, Cephalometrics & Facial Esthetics (~25%), Biomechanics, Tooth Movement Biology & Material Science (~20%), Early Interceptive Treatment & Dentofacial Orthopedics (~15%), Comprehensive Fixed Appliance Therapy, Adult Orthodontics & Clear Aligners (~10%), and Surgical Orthodontics, Cleft Lip/Palate & Retention/Relapse (~10%). The primary reference text is Contemporary Orthodontics by William R. Proffit, Henry W. Fields, Brent E. Larson, and David M. Sarver, supplemented by leading orthodontic journals and clinical guidelines. The written board consists of 100 four-option multiple-choice questions administered in a 100-minute morning session without negative marking. Achieving a minimum passing score of 70% is required to qualify for the oral and clinical phase, in which candidates defend case records of treated malocclusions (Class I bimaxillary protrusion, Class II division 1 and 2, Class III skeletal, open bite/deep bite, orthognathic surgery, and multidisciplinary adult treatment) and complete OSCE stations. This question bank is an independent English-language multiple-choice study adaptation developed by OpenExamPrep. It contains 100 comprehensive practice questions with detailed pedagogical explanations and distractor analyses to help orthodontic residents, postgraduates, and foreign-trained orthodontists prepare for the written board examination. The official Iranian examination is conducted primarily in Persian; this bank is neither an official translation nor a simulation of past official papers, and is not affiliated with or endorsed by Sanjesh Pezeshki or the Ministry of Health and Medical Education.

Exam sponsor: National Center for Health Assessment / Sanjesh Pezeshki (مرکز سنجش آموزش پزشکی) & Council for Dental and Specialized Education (شورای آموزش دندانپزشکی و تخصصی). The requirements and fees below concern the certification or admission exam, separate from our free practice resources.

Assessment

The Iranian Dental Specialty Board Examination (آزمون دانشنامه تخصصی دندانپزشکی) is administered annually in late summer (Shahrivar) by the National Center for Health Assessment (Sanjesh Pezeshki) under the oversight of the Council for Dental and Specialized Education of the Ministry of Health and Medical Education (MOHME). It represents the highest academic and clinical certification milestone for orthodontic residents graduating from accredited 3-year specialty training programs throughout Iran. The examination consists of two distinct stages: Phase 1 is a 100-item written multiple-choice test (100 minutes) based on canonical textbooks—principally Contemporary Orthodontics (Proffit, Fields, Sarver et al.) and core national board curricula. There is NO negative marking. Candidates must achieve a rigorous minimum score of 70% (70/100) on the written exam to advance to Phase 2. Phase 2 comprises an Objective Structured Clinical Examination (OSCE), treated clinical case portfolio defenses (presenting diverse malocclusion cases treated during residency), and an intensive oral viva voce examination before the National Board of Examiners.

Time Limit

100 minutes

Passing Score

70%

Exam / Certification Fees

Determined annually by the Ministry of Health and Medical Education (MOHME), payable online via the Sanjesh Pezeshki registration portal

Exam sponsor website

Fees, eligibility, and exam policies can change. Confirm them with the exam sponsor before applying or paying.

Official sources

Our practice resources: topics covered

We aim to reflect publicly available exam outlines and topic information in our study resources. Coverage, format, and difficulty may differ from the actual exam, and we cannot guarantee that every detail is accurate or current. Confirm exam requirements, fees, and policies with the official exam sponsor.

20%

Craniofacial Growth & Development & Etiology of Malocclusion

Theories of craniofacial morphogenesis (functional matrix hypothesis, cybernetic model, cartilaginous and sutural mechanisms), differential growth timing and cephalocaudal growth gradient, neurocranial and viscerocranial development, mandibular condyle biology, skeletal maturation staging (cervical vertebral maturation [CVM] stages I–VI, hand-wrist ossification landmarks), environmental and epigenetic influences, respiratory airway obstruction and adenoid facies, oral habits, and genetic syndromes affecting the craniofacial complex.

25%

Orthodontic Diagnosis, Cephalometrics & Facial Esthetics

Systematic clinical diagnostic examination, macro-, mini-, and micro-esthetics, vertical and transverse smile characteristics, Bolton anterior and overall tooth-size discrepancy calculations, arch space analysis, radiographic cephalometry (Steiner, Downs, Tweed, McNamara, Wits appraisal, Jarabak ratio), natural head position (NHP), soft tissue profile analysis (Holdaway, Rickett's E-line, Burstone line), 3D cone-beam computed tomography (CBCT) indications, airway volumetrics, and problem-oriented orthodontic treatment planning.

20%

Biomechanics, Tooth Movement Biology & Material Science

Periodontal ligament (PDL) vascular and cellular kinetics, optimal force levels for light continuous versus heavy force, hyalinization and undermining versus frontal resorption, RANK/RANKL/OPG signaling pathway, osteoclast and osteoblast recruitment, center of resistance and center of rotation, moment-to-force (M/F) ratios for uncontrolled tipping, controlled tipping, translation, and root torque, orthodontic wire metallurgy (austenitic and martensitic Nitinol, shape memory, superelasticity, beta-titanium TMA, stainless steel), friction mechanics, and skeletal anchorage with temporary anchorage devices (TADs).

15%

Early Interceptive Treatment & Dentofacial Orthopedics (Class II, Class III, Transverse)

Biological rationale and timing for early intervention, maxillary transverse deficiency and midpalatal suture maturation, rapid maxillary expansion (RME), slow expansion (SME), miniscrew-assisted rapid palatal expansion (MARPE), Class II dentofacial orthopedics (functional appliances: Twin Block, Herbst, Bionator, Frankel II; cervical, high-pull, and combination headgear), Class III skeletal orthopedics (reverse-pull facemask, bone-anchored maxillary protraction [BAMP], chin cup), serial extraction protocols, space management, impacted maxillary canine interceptive guidance, and oral habit cessation appliances.

10%

Comprehensive Fixed Appliance Therapy, Adult Orthodontics & Clear Aligners

Preadjusted edgewise appliance designs (Roth, MBT prescriptions, tip, torque, and in/out compensations), archwire sequencing protocols, leveling the curve of Spee, extraction versus non-extraction decision making, sliding mechanics versus frictionless closing loops, anchorage preservation strategies, finishing and detailing artistic bends, interdisciplinary adult orthodontics (periodontally compromised dentitions, pre-prosthetic molar uprighting, forced extrusion, implant site development), and clear aligner biomechanics, composite attachments, staging limitations, and tooth movement tracking.

10%

Surgical Orthodontics, Cleft Lip/Palate & Retention/Relapse

Combined orthodontic-surgical management of severe dentofacial deformities, presurgical orthodontic decompensation (dental leveling and arch alignment without camouflage), postsurgical orthodontic finishing, Le Fort I osteotomy, bilateral sagittal split osteotomy (BSSRO), intraoral vertical ramus osteotomy (IVRO), genioplasty, stability hierarchy of orthognathic surgical movements, distraction osteogenesis, multidisciplinary care of cleft lip and palate (presurgical infant orthopedics/NAM, secondary alveolar bone grafting timing, maxillary distraction), retention theory (PDL and supracrestal fiber reorganization), circumferential supracrestal fibrotomy, fixed and removable retainer regimens, and mechanisms of post-orthodontic relapse.

Preparing for the Iran Dental Specialty Board - Orthodontics Exam

What You Need to Know

Passing score: 70%
Assessment: The Iranian Dental Specialty Board Examination (آزمون دانشنامه تخصصی دندانپزشکی) is administered annually in late summer (Shahrivar) by the National Center for Health Assessment (Sanjesh Pezeshki) under the oversight of the Council for Dental and Specialized Education of the Ministry of Health and Medical Education (MOHME). It represents the highest academic and clinical certification milestone for orthodontic residents graduating from accredited 3-year specialty training programs throughout Iran. The examination consists of two distinct stages: Phase 1 is a 100-item written multiple-choice test (100 minutes) based on canonical textbooks—principally Contemporary Orthodontics (Proffit, Fields, Sarver et al.) and core national board curricula. There is NO negative marking. Candidates must achieve a rigorous minimum score of 70% (70/100) on the written exam to advance to Phase 2. Phase 2 comprises an Objective Structured Clinical Examination (OSCE), treated clinical case portfolio defenses (presenting diverse malocclusion cases treated during residency), and an intensive oral viva voce examination before the National Board of Examiners.
Time limit: 100 minutes
Exam / certification fees: Determined annually by the Ministry of Health and Medical Education (MOHME), payable online via the Sanjesh Pezeshki registration portal Official sources

Using Our Practice Resources

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Iran Dental Specialty Board - Orthodontics: Suggested Study Strategy

1Master the fundamental growth theories and timing milestones from Proffit: focus on Moss's functional matrix hypothesis, the cybernetic model, condylar secondary cartilage biology, and the exact staging and skeletal peak timing of cervical vertebral maturation (CVM stages III and IV).

2Dedicate focused review to orthodontic biomechanics, specifically center of resistance locations for single- and multi-rooted teeth, moment-to-force (M/F) ratios, and the mechanical properties of superelastic NiTi versus beta-titanium (TMA) wires.

3Understand the cephalometric analysis parameters thoroughly: know standard normal values and geometric interpretations for Steiner (SNA, SNB, ANB), Downs, Tweed triangle (FMA, FMIA, IMPA), McNamara (effective midfacial and mandibular lengths), and the Wits appraisal.

4Thoroughly analyze orthopedic timing and appliance mechanics: distinguish between indications, skeletal versus dental effects, and reciprocal forces for rapid maxillary expansion (RME), reverse-pull facemasks, cervical versus high-pull headgear, and functional appliances like Twin Block and Herbst.

5Review orthognathic surgery decompensation rules and stability hierarchies: know the most stable surgical movements (maxillary superior repositioning, mandibular advancement) versus the least stable (transverse maxillary expansion, mandibular setback), and remember that this OpenExamPrep resource is an independent English-language adaptation to be used alongside core textbook study.

Frequently Asked Questions

What is the Iranian Dental Specialty Board Examination in Orthodontics?

The Iranian Dental Specialty Board Examination in Orthodontics (آزمون دانشنامه تخصصی دندانپزشکی - ارتودانتیکس) is the official national credentialing examination conducted annually by Sanjesh Pezeshki under the authority of the Council for Dental and Specialized Education. It is the culminating qualification for graduates of 3-year accredited orthodontic residency programs in Iran, conferring the National Specialty Board Certificate (Danishnameh Takhassosi), which is legally required to hold academic university faculty appointments and practice as a recognized orthodontic specialist.

How is the Iranian Orthodontics Board Examination structured?

The examination consists of two consecutive stages: Phase 1 is a 100-question written multiple-choice test lasting 100 minutes administered in a single session. Candidates who achieve the required passing score of 70% (at least 70 correct out of 100) qualify to sit for Phase 2, which consists of an Objective Structured Clinical Examination (OSCE), treated clinical case portfolio defenses presented before the national examination committee, and an oral board viva voce examination.

Is there negative marking on the Iranian Orthodontics written board exam?

No. The written dental specialty board examination (Danishnameh) has no negative marking penalty. Incorrect answers receive 0 marks and do not deduct points from correct responses. Examinees are strongly advised to answer all 100 questions.

What primary textbooks and references are tested on the examination?

The core reference text for the national board examination is William R. Proffit's Contemporary Orthodontics (co-authored by Fields, Larson, and Sarver), which serves as the principal foundation for growth, diagnosis, biomechanics, orthopedics, fixed appliances, and surgical orthodontics. Additional referenced texts include Graber's Orthodontics: Current Principles and Techniques, McNamara's Orthodontics and Dentofacial Orthopedics, and relevant scientific guidelines released by the Iranian Board of Orthodontics.

What is the difference between the Specialty Certificate (Govahi-nameh) and Board Certificate (Danishnameh)?

The Specialty Certificate (Govahi-nameh) is awarded by the candidate's university upon successful completion of residency coursework and hospital requirements, certifying the completion of specialty training for clinical practice. The National Specialty Board Certificate (Danishnameh Takhassosi) is the higher national honor awarded by the Ministry of Health and Sanjesh Pezeshki upon passing both written and oral/practical board examinations, qualifying the holder for academic faculty appointments, clinical leadership, and top-tier hospital positions.

Is this OpenExamPrep question bank an official publication of Sanjesh Pezeshki?

No. This question bank is an independent English-language multiple-choice practice and study adaptation authored by OpenExamPrep for conceptual review and mastery of orthodontic specialty literature. The official Iranian national examination is administered in Persian by Sanjesh Pezeshki; this resource is neither an official translation nor a past-paper simulation, and has no affiliation with or endorsement from the Ministry of Health and Medical Education or Sanjesh Pezeshki.