Podcast
Questions and Answers
What does distal inclination refer to in dentistry?
What does distal inclination refer to in dentistry?
What is defined as infraocclusion?
What is defined as infraocclusion?
What condition describes the rotation of a tooth towards the tongue?
What condition describes the rotation of a tooth towards the tongue?
Which term is used to describe teeth that are irregularly arranged within the dental arch?
Which term is used to describe teeth that are irregularly arranged within the dental arch?
Signup and view all the answers
What does crowding refer to in dentistry?
What does crowding refer to in dentistry?
Signup and view all the answers
Which term describes the outward tilting of incisor and canine teeth?
Which term describes the outward tilting of incisor and canine teeth?
Signup and view all the answers
What is the meaning of supraocclusion in relation to tooth positioning?
What is the meaning of supraocclusion in relation to tooth positioning?
Signup and view all the answers
What does transposition refer to in dental terms?
What does transposition refer to in dental terms?
Signup and view all the answers
What is the term used to describe the forward placement of a jaw?
What is the term used to describe the forward placement of a jaw?
Signup and view all the answers
Which skeletal class is characterized by the maxilla lying ahead of the mandible?
Which skeletal class is characterized by the maxilla lying ahead of the mandible?
Signup and view all the answers
What skeletal occlusion is associated with an abnormal relationship between upper and lower jaws in a transverse plane?
What skeletal occlusion is associated with an abnormal relationship between upper and lower jaws in a transverse plane?
Signup and view all the answers
In which skeletal class is the profile typically retrognathic?
In which skeletal class is the profile typically retrognathic?
Signup and view all the answers
Which modification of Angle’s classification introduces terms such as 'Neutrocclusion' and 'Distocclusion'?
Which modification of Angle’s classification introduces terms such as 'Neutrocclusion' and 'Distocclusion'?
Signup and view all the answers
In Dewey’s modification, what is classified under Type 2 of Class I?
In Dewey’s modification, what is classified under Type 2 of Class I?
Signup and view all the answers
Division 2 of Class II is characterized by which of the following?
Division 2 of Class II is characterized by which of the following?
Signup and view all the answers
What skeletal classification indicates that the maxilla and mandible are in harmony with each other?
What skeletal classification indicates that the maxilla and mandible are in harmony with each other?
Signup and view all the answers
Which of the following is NOT a characteristic of the British Standard Classification of Incisor Relationship?
Which of the following is NOT a characteristic of the British Standard Classification of Incisor Relationship?
Signup and view all the answers
Which aspect is not differentiated by Angle's classification?
Which aspect is not differentiated by Angle's classification?
Signup and view all the answers
Which condition represents the backward placement of a jaw?
Which condition represents the backward placement of a jaw?
Signup and view all the answers
What type of occlusion is defined by Lischer as 'Bucco-occlusion'?
What type of occlusion is defined by Lischer as 'Bucco-occlusion'?
Signup and view all the answers
What defines the skeletal class of a malocclusion where the mandible has overgrowth leading to an obtuse mandibular angle?
What defines the skeletal class of a malocclusion where the mandible has overgrowth leading to an obtuse mandibular angle?
Signup and view all the answers
What is one limitation of Angle's classification?
What is one limitation of Angle's classification?
Signup and view all the answers
What type of crossbite is present under Type 4 of Class I in Dewey’s modification?
What type of crossbite is present under Type 4 of Class I in Dewey’s modification?
Signup and view all the answers
Which malocclusion is described as 'Mesioversion' according to Lischer's terminology?
Which malocclusion is described as 'Mesioversion' according to Lischer's terminology?
Signup and view all the answers
What characterizes Class II Division 1 incisor relationship?
What characterizes Class II Division 1 incisor relationship?
Signup and view all the answers
Which incisor classification indicates a reduced overjet?
Which incisor classification indicates a reduced overjet?
Signup and view all the answers
In Simon's classification, what is the term for the dental arch closer to the Frankfort horizontal plane?
In Simon's classification, what is the term for the dental arch closer to the Frankfort horizontal plane?
Signup and view all the answers
Which canine classification describes when the mesial slope of the upper canine is ahead of the distal slope of the lower canine?
Which canine classification describes when the mesial slope of the upper canine is ahead of the distal slope of the lower canine?
Signup and view all the answers
What is the effect of a dental arch that is more anteriorly placed in relation to the orbital plane?
What is the effect of a dental arch that is more anteriorly placed in relation to the orbital plane?
Signup and view all the answers
Which feature is associated with Class II Division 2 incisor relationship?
Which feature is associated with Class II Division 2 incisor relationship?
Signup and view all the answers
What is referred to as distraction in Simon's classification?
What is referred to as distraction in Simon's classification?
Signup and view all the answers
What type of skeletal malocclusion involves defects in size, position, or relationship between the jaws?
What type of skeletal malocclusion involves defects in size, position, or relationship between the jaws?
Signup and view all the answers
What is the primary function of the alveolar bone?
What is the primary function of the alveolar bone?
Signup and view all the answers
Which of the following describes a malocclusion?
Which of the following describes a malocclusion?
Signup and view all the answers
In malocclusion, which category represents the misposition of individual teeth?
In malocclusion, which category represents the misposition of individual teeth?
Signup and view all the answers
What type of displacement is described as a tooth being moved toward the mid-line of the arch?
What type of displacement is described as a tooth being moved toward the mid-line of the arch?
Signup and view all the answers
Which of the following categories does NOT classify intra-arch problems in malocclusion?
Which of the following categories does NOT classify intra-arch problems in malocclusion?
Signup and view all the answers
What is a common consequence of infraversion in teeth?
What is a common consequence of infraversion in teeth?
Signup and view all the answers
Which label does NOT belong to the lower dental arch?
Which label does NOT belong to the lower dental arch?
Signup and view all the answers
What term is used to describe a tooth that is inclined in a forward position?
What term is used to describe a tooth that is inclined in a forward position?
Signup and view all the answers
Which defines Class II Division 1 malocclusion?
Which defines Class II Division 1 malocclusion?
Signup and view all the answers
What is a notable de-merit of Angle’s Classification?
What is a notable de-merit of Angle’s Classification?
Signup and view all the answers
Which category of malocclusion describes the mesiobuccal cusp of the lower first molar occluding mesial to the Class I position?
Which category of malocclusion describes the mesiobuccal cusp of the lower first molar occluding mesial to the Class I position?
Signup and view all the answers
What is a characteristic of Class II Division 2 malocclusion?
What is a characteristic of Class II Division 2 malocclusion?
Signup and view all the answers
Which of the following is a merit of Angle’s Classification?
Which of the following is a merit of Angle’s Classification?
Signup and view all the answers
Which aspect of malocclusion is NOT considered in Angle's Classification?
Which aspect of malocclusion is NOT considered in Angle's Classification?
Signup and view all the answers
What happens during a pseudo class III condition?
What happens during a pseudo class III condition?
Signup and view all the answers
Which statement is true regarding Class I malocclusion?
Which statement is true regarding Class I malocclusion?
Signup and view all the answers
Study Notes
Malocclusion of Teeth
- Malocclusion is a condition where teeth deviate from their normal relationship to other teeth in the same arch and the opposing arch.
- Malocclusion can be simple or complex.
- Malocclusion can be categorized by teeth, dental arches, or dental bases (skeletal).
Dental Arch
- The dental arch is the arch formed by the crowns of the teeth.
- This includes the upper and lower arches.
Alveolar Bone
- Alveolar bone comprises parts of the maxilla and mandible that form and support tooth sockets.
- The alveolar bone is a specialized bone structure crucial for holding teeth in place.
- It surrounds the root of the tooth
Intra-arch Problems
-
Sagittal Problems:
- Labioversion: Tooth tilted toward the lips.
- Linguoversion: Tooth tilted toward the tongue.
- Mesioversion: Tooth tilted toward the midline.
- Distoversion: Tooth tilted away from the midline.
-
Vertical Problems:
- Supraversion: Tooth positioned above the normal level.
- Infraversion: Tooth positioned below the normal level.
- Rotation: Tooth rotated around its long axis.
- Transposition: Two teeth have exchanged positions during development.
- Imbrication: Teeth are irregularly arranged due to lack of space.
- Crowding: Lack of space for all teeth to fit normally within the jaws, resulting in tooth rotations or displacement.
Additional Malposition Details
- Various malpositions of teeth are defined by their direction or nature of displacement: mesial displacement, distal displacement, mesial inclination, distal inclination, lingual inclination, labial inclination, buccal inclination, labial and buccal displacement, infraocclusion, supraocclusion.
Mesial and Distal Displacement
- Mesial displacement: Tooth bodily displaced towards the midline of the arch.
- Distal displacement: Tooth bodily displaced away from the midline of the arch.
Mesial and Distal Inclination
- Mesial inclination: Tooth tilted along the dental arch towards the midline, with its crown located too close to the midline.
- Distal inclination: Tooth tilted along the dental arch away from the midline, with its crown located too far from the midline.
Lingual Inclination
- Lingual inclination: Tooth tilted towards the tongue. Retroclination is often used to describe the lingual tilting of anterior teeth.
Labial and Buccal Inclination/Displacement
- Labial inclination: Tooth tilted towards the lips.
- Buccal inclination: Term used for molars/premolars; refers to tilting towards the cheek. Labial and buccal displacement describe bodily outward displacement of teeth.
Infraocclusion and Supraocclusion
- Infraocclusion: Tooth's occlusal surface has not reached the standard level of other teeth in the arch.
- Supraocclusion: Tooth has excessively erupted beyond the standard level of the other teeth.
Rotations (Mesiolingual and Distolingual)
- Mesiolingual rotation: Tooth rotated around its long axis such that its mesial surface faces the tongue.
- Distolingual rotation: Tooth rotated in the opposite direction (distal surface toward the tongue).
Inter-arch Problems
- Sagittal Problems:
- Class II malocclusion: Relationship of upper and lower teeth where the lower jaw is behind the upper jaw.
- Class III malocclusion: Relationship of upper and lower teeth where the lower jaw is ahead of the upper jaw.
- Transverse Problems:
- Crossbites: One or more teeth in an incorrect transverse position (buccal, lingual, or labial) relative to their opposing teeth.
- Scissors bite: Total crossbite with the opposing mandibular dentition completely positioned within occlusal contact.
- Vertical Problems:
- Deep bite/increased overbite: Excessive overlap of the upper teeth over the lower teeth.
- Open bite: Lack of vertical relationship between upper and lower teeth.
Angle's Classification of Malocclusion
- Angle proposed the first classification system in 1899, based on the relationship of the mesiobuccal cusp of the upper first molar to the buccal groove of the lower first molar.
- Class I: normal mesiobuccal cusp relation.
- Class II: mesiobuccal cusp of the upper first molar is mesially positioned to the buccal groove of the lower first molar.
- Class III: mesiobuccal cusp of the upper first molar is distally positioned to the buccal groove of the lower first molar.
Modifications to Angle's System
- Lischer and Dewey proposed modifications to Angle's system.
British Standard Classification of Incisor Relationship
- Classification based on the relationship of the lower incisors to the upper incisors (ignoring molar relationships in some cases).
- Class I: Lower incisor edges immediately below/occlude with cingulum plateau of upper central incisors.
- Class II: Lower incisor edges posterior to the cingulum plateau of upper incisors, with two subclasses (division 1: increased overjet, division 2: minimal overjet).
- Class III: Lower incisor edges anterior to the cingulum plateau of upper incisors.
Canine Classification
- Class I canine: Mesial slope of the upper canine is in line with the distal slope of the lower canine.
- Class II canine: Mesial slope of the upper canine is anterior to the distal slope of the lower canine.
- Class III canine: Mesial slope of the upper canine is posterior to the distal slope of the lower canine.
Simon's Classification (1926)
- Used three anthropologic planes to classify dental arches:
- Frankfort horizontal plane (eye-ear plane).
- Orbital plane.
- Mid-sagittal plane.
Skeletal Malocclusion
- Skeletal defects in jaw size, position, or relationship can result in malocclusion, evident in sagittal, vertical, and transverse planes.
- Skeletal malocclusions include prognathic jaws (protruding lower jaw), retrognathic jaws (retracted lower jaw), skeletal deep bites, skeletal open bites, and skeletal cross bites.
Skeletal Classification
- Skeletal Class I: Maxilla and mandible are in harmony.
- Skeletal Class II: Maxilla is more prominent than the mandible (retrognathic).
- Skeletal Class III: Mandible is more prominent than the maxilla (prognathic).
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge of key terms in orthodontics and dentistry with this quiz. Questions cover definitions and classifications related to tooth positioning, skeletal relationships, and more. Perfect for dental students and professionals alike!
