Orthodontic Diagnosis Question And Answers

Orthodontic Diagnosis Important Notes

• Cephalic index
  • The shape of the head can be evaluated based on a cephalic index of the head formulated by Martin and Saller
  • Cephalic index = posterior facial height / anterior facial height

• Facial form

• Types of lips

• Facial divergence

• Nasolabial angle
  • It is an angle formed between the lower border nose and a line connecting the nose and upper lips
  • The normal value is 110 degrees
  • Reduced in patients with proclined maxillary anterior or prognathic maxillary
  • Increased in patients with retrognathic maxilla or reclined maxillary anterior
• Path of closure of mandible
  • Backward in class 2 division 2
  • Forward in pseudo-class 3
  • Lateral in unilateral crossbites

Orthodontic Diagnosis Long Essays

Question 1. Discuss in detail the various diagnostic aids used in orthodontics.
Answer.

Diagnosis:

• It involves the collection of pertinent data in a systemic manner to help identify the nature and cause of the problem

Read And Learn More: Orthodontics Short And Long Essay Question And Answers

Diagnosis Aids:

• Comprehensive orthodontic diagnosis is established by the use of certain clinical implements called diagnostic aids

Types Of Diagnosis Aids:

• Essential Diagnostic aids
  • Case history
  • Clinical examination
  • Study models
  • Certain radiographs
  • Facial radiographs
• Supplemental diagnostic aids
  • Specialized radiographs
  • Electromyographs
  • Hand wrist radiographs
  • Endocrine tests
  • Estimation of basal metabolic rates
  • Diagnostic set-up
  • Occlusograms
• Essential Diagnostic aids:
  • Aids that are important for all cases
  • Involves

Case History involves:

• Personal details:
  • Name – For maintaining a record
    • Addressing patient
    • For communication
  • Age – for treatment planning
    • Growth period – Myofunctional appliances
    • After cessation of growth-surgical treatment
  • Sex – growth spurts differ in both sex
  • Address – for further correspondence

• Chief complaints: Help to identify the expectations of the patient
• Medical history: epilepsy, diabetes, and blood dyscrasias complicate the treatment
• Dental history: to know the attitude of the patient toward treatment
• Pre-natal history: for knowing the condition of the mother during pregnancy
  • Forcep delivery leads to cross-bite
• Post-natal history: to know milestones of development
• Family history: some occlusions like clefts are hereditary

Clinical Examination:

General:

• Height
• Weight
• Gait
• Posture
• Body build

Extra-Oral:

• Head shape
• Facial form
• Facial Profile
• Facial symmetry
• Facial divergence
• Anteroposterior relationship
• Facial proportions
• Lips
• Nose
• Nasolabial angle

Intra-Oral:

• Tongue
• Palate
• Gingiva
• Frenal attachment
• Tonsils
• Adenoids
• Dentition

Functional Examination:

• Postural rest position
• Path of closure
• TMJ
• Swallowing
• Speech
• Respiration

Study models:

• Provide a 3D view of the situation

Uses Of Orthodontics:

• Studies occlusion from all aspects
• Enables accurate measurement
• Treatment planning
• Assess the severity of malocclusion
• Motivate the patient
• For mock surgery
• For transparency records

Steps in Fabrication:

• Impression making – By alginate
• Disinfecting it – By Biocide
• Casting the impression – By model stone
• Basing and trimming the cast
• Finishing and Polishing – By fine-grained sandpaper

Radiographs:

• Commonly used radiographs are

Cephalometric: For skeletal malocclusion

• IOPA – to know the bone condition
• Occlusion radiograph – for arch length

Facial Photographs:

• To compare pre and post-treatment conditions

Supplemental Diagnostic Aids

• Require only in specialized cases
• Includes – electromyography
  • Hand wrist radiograph
  • Endocrine test
  • Estimation of BMR (Basal Metabolic Rate)
  • Diagnostic set up
  • Occlusograms
  • MRI, CT scan

Question 2. What are various diagnostic aids in orthodontics? Write in detail about clinical examination and case history records.
Answer.

Diagnostic Aids:

Essential Diagnostic aids:

• Case history
• Clinical examination
• Study models
• Certain radiographs
• Facial photographs

Supplemental diagnostic aids:

• Specialized radiographs
• Electromyographs
• Hand wrist radiographs
• Endocrine tests
• Estimation of basal metabolic rates
• Diagnostic set-up
• Occlusograms

Case History involves:

• Personal details:
  • Name – For maintaining a record
    • Addressing patient
    • For communication
  • Age – for treatment planning
    • Growth period – Myofunctional appliances
    • After cessation of growth-surgical treatment
  • Sex – growth spurts differ in both sex
  • Address – for further correspondence
• Chief complaints: Help to identify the expectations of the patient
• Medical history: Epilepsy, diabetes, and blood dyscrasias complicate the treatment
• Dental history: To know the attitude of the patient toward treatment
• Pre-natal history: For knowing the condition of the mother during pregnancy
  • Forcep delivery leads to cross-bite
• Post-natal history: To know milestones of development
• Family history: Some occlusions like clefts are hereditary

Clinical Examination:

General:

• Height
  • Provide information on physical growth and maturation of the patient that may influence oro-facial development
• Weight
  • Provide information on the physical growth and maturation of the patient that may influence oro-facial development
• Gait
  • Gait abnormality is associated with neuromuscular problems
• Posture
  • Abnormal posture can predispose to malocclusion
• Body build
  • Types:
    • Aesthetic
      • Thin physique
      • Narrow dental arches
    • Plethoric
      • Obese persons
      • Large, square dental arches
    • Athletic
      • Normal built
      • Normal-size dental arches

Extra-Oral:

• Head shape
  • Types:
    • Mesocephalic
      • The average shape of the head
      • Normal dental arches
    • Dolichocephalic
      • Long and narrow head
      • Narrow dental arches
    • Brachycephalic
      • Broad and short head
      • Broad dental arches

Facial form:

• Types:
  • Mesoprosopic
    • Average face from
  • Euryprosopic
    • Broad and short facial form
  • Leptoprosopic
    • Long and narrow facial form

Facial profile:

• Examined by viewing the patient from the side
• Diagnoses gross deviations in the maxillo-mandibular relationship

Types:

• Straight
• Convex
• Concave

Facial symmetry:

• Determines disproportions of the face in transverse and vertical planes

Facial divergence:

• It is an anterior or posterior inclination of the lower face relative to the forehead

Types Of Facial Divergence:

• Anterior divergence
• Posterior divergence
• Straight or orthognathic
• Anteroposterior relationship
  • This can be assessed by the following
• Seat the patient in an upright position
• Ask to occlude gently
• Place index and middle finger at soft tissue points A and B respectively
• In class 1 hand is at an even level
• In class 2 Index finger is anterior to the middle finger
• In class 3 Middle finger is ahead of the forefinger

Facial proportions:

• The face is divided into three equal thirds by four horizontal planes
• At the level of hairline
• Supraorbital ridge
• The base of the nose
• The inferior border of the chin

Lips:

• Types:
  • Competent lips
  • Incompetent lips
  • Potentially incompetent lips
  • Everted lips

Note:

• It contributes to the esthetics of the face

Nasolabial angle:

• It is the angle formed between the lower border of the nose and the line connecting the intersection of the nose and the upper lip
• It is normally 110 degrees

Intra-Oral:

Tongue:

• Abnormalities in the tongue disturb muscle balance and equilibrium leading to malocclusion

Palate:

• Examined for
  • Palatal depth
  • Presence of swelling
  • Mucosal ulceration
  • Presence of clefts
  • Third rugae

Gingiva:

• Examined for
  • Inflammation
  • Recession
  • Mucogingival lesions

Frenal attachment:

• Abnormal labial frenum leads to midline diastema
• Ankyloglossia leads to the narrowing of the maxillary arch

Tonsils:

• Abnormal inflamed tonsils cause alteration in tongue and jaw posture

Adenoids:

Dentition:

• Assess the following
  • Number of teeth present
  • Number of teeth missing
  • Status of teeth-erupted or unerupted
  • Presence of caries, restorations, or malformed
  • Assess occlusion
  • Assess overjet and overbite
  • Assess individual tooth irregularities like rotations, intrusion, and extrusions
  • Assess transverse relationship
  • Examine the upper and lower arch separately

Question 3. Exumerate essential diagnostic aids. Describe study models in detail.
Answer.

Essential Diagnostic Aids:

• Case history
• Clinical examination
• Study models
• Certain radiographs
• Facial photographs

Study Models:

Uses Of Diagnostic Aids:

• Studies occlusion from all aspects
• Enables accurate measurement
• Treatment planning
• Assess the severity of malocclusion
• Motivate the patient
• For mock surgery
• For transparency records

Requirements Of Diagnostic Aids:

• Should accurately reproduce oral structures
• Should be pleasing to the eye
• Should accurately reproduce occlusion
• Should have a clean, smooth surface
• Should reproduce as much of the alveolar process as possible

Parts Of Diagnostic Aids:

• Anatomic portion
• Artistic portion

Steps:

• Impression making

Disinfecting the impression

• Casting the impression – Using orthodontic stone/model stone
• Basing and trimming of cast

• Trimming
  • Step 1: Trimming of mandibular base
  • Step 2: The back of the mandibular model is made perpendicular to the midline
  • Step 3: Both casts should occlude
  • Step 4: Backs of both casts are made right-angled to base
  • Step 5: Buccal cuts are made on mandibular cast
  • Step 6: Anterior segments made on lower cast
  • Step 7: Posterior cuts on the lower cast
  • Step 8: Buccal cuts made on the upper cast
  • Step 9: Anterior cuts on the upper cast
  • Step 10: Posterior cuts on the upper cast

• Finishing and polishing – Done using fine-grained sandpaper

Orthodontic Diagnosis Short Essays

Question 1. Intra-oral X-rays in Orthodontics
Answer.

Types Of Intra-Oral X-rays:

Intra-Oral Periapical Radiograph:

• Techniques:
  • Paralleling technique
  • Bisecting angle technique
• Uses:
  • View the presence/absence of teeth
  • Supernumerary teeth
  • Root formation
  • Periapical pathology
  • PDL space
  • The contour of alveolar bone – to assess the abnormality
  • Unerupted teeth – for tooth morphology
• Disadvantages:
• Not convenient for the entire dentition
• Gag reflex
• Uncomfortable for children

Bitewing:

• Uses:
  • To assess the height and contour of bone
  • To evaluate periodontal changes
  • To assess interproximal calculus

Occlusal:

• Uses:
  • For impacted/unerupted teeth
  • For supernumerary teeth
  • For foreign bodies
  • To view the effects of the arch expansion procedure

Question 2. Inter-incisal angle.
Answer.

It is the angle formed between the long axis of the upper and lower incisors

• Value – 135.4°
• Range – 130 – 150.5°

Significance Of Inter-incisal Angle:

• Increased in Class 2, Division 2
• Decreased – Class 1 bimaxillary protrusion
  • Class 2 Division 1

Question 3. Occlusal X-ray.
Answer.

Advantages Of Occlusal X-ray:

• Views a large segment of the dental arch
• For viewing palate and floor of mouth
• Useful in trismus

Uses Of Occlusal X-ray:

• Locate impacted teeth
• Locate fracture
• Locate supernumerary teeth
• Locate foreign bodies
• Locate effects of arch expansion procedures
• Assess the arch length
• Assess any pathology of jaws

Question 4. Overjet and Overbite.
Answer.

Overjet: It is the horizontal overlapping of maxillary and mandibular anterior

Value: 1.5 – 2mm

Significance Of Overjet: Increases in open bite cases

• Increases in anterior proclination

Overbite: It is the vertical overlapping of maxillary and mandibular anterior

Value: 1.5 – 2mm

Significance Of Overbit: Decrease – Deep bite

Increase: Open bite

Orthodontic Diagnosis Short Questions And Answers

Question 1. Facial Divergence.
Answer.

It is defined as an anterior/posterior inclination of the lower face relative to the forehead

Types Of Facial Divergence:

• Anterior divergent: A line between the forehead and chin inclines anteriorly
• Posterior divergent: A line between forehead and chin inclines posteriorly
• Straight/Orthognathic: A line between the forehead and chin is straight or perpendicular to the floor.

Question 2. Uses of Panoramic Radiograph./Orthopentogram
Answer.

• Assessing dental development
  • Studying root resorption/root formation
  • For Ankylosis
  • Impacted teeth
  • Path of eruption
  • Diagnose pathology
  • Status of eruption
  • Unerupted teeth

Question 3. Bite Wing Radiographs.
Answer.

Records coronal part of upper and lower dentition together

Uses Of Bite Wing Radiographs:

• For proximal caries
• For interdental bone contour
• For secondary caries
• Detect overhanging restoration
• Detect periodontal changes
• Detect interproximal calculus

Question 4. Electromyography.
Answer.

Used for recording the electrical activity of muscles

Types Of Electrodes Used:

• Surface electrode – Plated superficially
• Needle electrode – Placed deeply

Useful In:

• In severe Class 2 division 1 malocclusion
• Abnormal buccinator activity
• Overclosure of jaws
• Cerebral palsy
• After orthodontic therapy

Question 5. Clinical Evaluation of Facial Profile.
Answer.

The patient is viewed from the side

Reference Lines:

• A line from forehead to point A
• A line from point A to pogonion

Types Of Profiles:

• Straight: Two lines straight line Ex. Class 1 cases
• Convex: Two lines form an angle with concavity facing tissue Ex. Class 2, Division 1
• Concave: Two lines form an angle with convexity facing tissue Ex. Class 3 malocclusion

Question 6. Importance of Family History.
Answer.

• Some malocclusions are hereditary
• These affect the treatment planning
• Thus details of it should not be neglected Ex. Class 2 malocclusion, Cleft lip and palate

Question 7. Kesling’s diagnostic setup.
Answer.

• Proposed by H.D. Kesling
• Used for assessing the effect of treatment

Procedure Of Kesling’s Diagnostic:

Question 8. Freeway Space.
Answer.

• The position of the mandible at which muscles that are useful in opening and closing of jaws are in a state of minimal contraction is called posture rest position
• At this position, space is present between both the jaws
• This is called free-way space

Value – 3mm

Site – In canine region

Question 9. Gnathostatic Models.
Answer.

• Type of study model
• Uses: Provide 3D view of occlusion
• For treatment planning
• For assessing the outcome

Gnathostatic:

Question 10. Overjet.
Answer.

• It is a horizontal overlapping of the maxillary and mandibular anterior
• Value: 1.5 – 2mm
• Significance Of Overjet: Increases in open bite cases
  • Increases in anterior proclination

Question 11. Nasolabial angle.
Answer.

• It is the angle formed between the lower border of the nose and the line connecting the intersection of the nose and the upper lip
• It is normally 110 degrees
• Reduces in
  • Patients having proclined upper anterior or prognathic maxilla
• Increases in
  • Patients with retrognathic maxilla or reclined maxillary anterior

Question 12. Cephalic index
Answer.

• The cephalic index was described by Martin and Saller in 1957
  • It is calculated as follows
• Cephalic index = Maxillary skull width / Maxillary skull length

Interpretation Of Cephalic Index:

• Value – 76-80.9
  • Indicates mesocephalic individuals
• Value – 81-85.4
  • Indicates brachycephalic individuals
• Value < 75.9
  • Indicates dolichocephalic individuals
• Value > 85.5
  • Indicates hyperbradycephalic

Question 13. Orthodontic study models
Answer.

Uses Of Orthodontic Study Models:

• Studies occlusion from all aspects
• Enables accurate measurement
• Treatment planning
• Assess the severity of malocclusion
• Motivate the patient
• For mock surgery
• For transparency records

Requirements Of Orthodontic Study Models:

• Should accurately reproduce oral structures
• Should be pleasing to the eye
• Should accurately reproduce occlusion
• Should have a clean, smooth surface
• Should reproduce as much of the alveolar process as possible

Parts Of Orthodontic study models:

• Anatomic portion
• Artistic portion

Question 14. Importance of medical history
Answer.

• Some medical conditions contraindicate the use of orthodontic appliances
• They may require special precautionary measures to be taken before or during orthodontic therapy
• It is advisable to delay orthodontic treatment in patients suffering from epilepsy until it is controlled
• Patients with a history of blood dyscrasias may need special management if extractions are planned
• Diabetic patients can undergo orthodontic therapy if it is under control
• Patients having rheumatic fever or cardiac anomalies require antibiotic coverage for certain dental procedures
• Children who are severely handicapped either mentally or physically may require special management
• The use of aspirin may impede orthodontic tooth movement
• Patients suffering from acute, debilitating conditions should be allowed to recover before initiating orthodontic treatment

Orthodontic Diagnosis Viva Voce

• Hyperactive mental activity and abnormal buccinators activity are seen in class 2 division 1
• Overclosure of jaws is associated with accentuated temporalis muscle activity
• Normally the upper lip covers the anterior labial surface of the upper anterior except for the incisal 2-3mm while the lower lip covers the entire labial surface of the lower anterior and 2–3mm of the incisal edge of the upper anterior