WILK ch16 & PAT ch16 Angles Classification

What are the three stages of human dentition?

Primary (deciduous) dentition, mixed (transitional) dentition, and permanent dentition.

Between what ages does mixed dentition typically occur?

Roughly ages 6 to 12 years.

What is a succedaneous tooth?

A permanent tooth that erupts into the position of an exfoliated primary tooth.

By what age are all primary teeth normally exfoliated?

By age 13 years.

Which permanent teeth are usually the first to erupt, around age 6 to 7?

The permanent first molars, followed closely by the mandibular central incisors.

Who developed the classification system for occlusion still used today, and in what year?

Dr. Edward H. Angle, in 1887 (also cited as 1900 in one source).

What is Angle's classification primarily based on?

The relationship of the mandibular first molar to the maxillary first molar (specifically the buccal groove position).

What defines normal (Class I) occlusion according to Angle?

The mesiobuccal cusp of the maxillary first molar occludes with the buccal groove of the mandibular first molar.

What is the other name for Angle's Class I malocclusion?

Neutrocclusion.

What is the other name for Angle's Class II malocclusion?

Distocclusion.

What is the other name for Angle's Class III malocclusion?

Mesiocclusion.

In Angle's Class II, where is the mandibular buccal groove positioned relative to normal?

Distal to the mesiobuccal cusp of the maxillary first molar by at least the width of a premolar.

What distinguishes Class II Division 1 from Class II Division 2?

In Division 1, all four maxillary incisors are protruded; in Division 2, the maxillary lateral incisors protrude while the central incisors retrude.

In Angle's Class III, where is the mandibular buccal groove positioned relative to normal?

Mesial to the mesiobuccal cusp of the maxillary first molar by at least the width of a premolar.

What facial profile is typically associated with Class II malocclusion?

Retrognathic (convex profile), with a prominent maxilla and retruded mandible.

What facial profile is typically associated with Class III malocclusion?

Prognathic (concave profile), with a prominent, protruded mandible.

What facial profile is typically associated with normal (Class I) occlusion?

Mesognathic (relatively flat/straight profile).

If the molars are missing or malaligned, what is used instead to classify occlusion?

The relationship of the mandibular canine to the maxillary canine.

What is overbite?

The vertical distance by which the maxillary incisors overlap the mandibular incisors.

What is overjet?

The horizontal distance between the incisal edges of the maxillary and mandibular incisors.

What is underjet?

A condition where the maxillary incisors are lingual to the mandibular incisors, creating a measurable horizontal distance in the reverse direction of overjet.

What is an open bite?

A lack of occlusal or incisal contact between certain maxillary and mandibular teeth because one or both fail to reach the line of occlusion.

What is a crossbite?

A condition where maxillary or mandibular teeth are positioned facial or lingual to their normal position relative to the opposing arch.

What is an edge-to-edge (or end-to-end) bite?

A bite in which the incisal or occlusal surfaces of the maxillary and mandibular teeth meet directly rather than overlapping as in normal occlusion.

What is the difference between a malrelationship of the dental arches and a malposition of an individual tooth?

A malrelationship affects how the whole arches meet (e.g., crossbite, open bite), while a malposition describes one tooth being out of place within an otherwise normal arch.

Define labioversion.

A tooth positioned labial (toward the lips) to its normal position.

Define linguoversion.

A tooth positioned lingual (toward the tongue) to its normal position.

Define buccoversion.

A tooth positioned buccal (toward the cheek) to its normal position.

Define supraversion.

A tooth elongated above the normal line of occlusion.

Define infraversion.

A tooth depressed below the normal line of occlusion (e.g., a submerged or ankylosed primary tooth).

Define torsiversion.

A tooth that is turned or rotated from its normal position.

What is the difference between static and dynamic (functional) occlusion?

Static occlusion is the relationship of the teeth when the jaws are closed; dynamic occlusion consists of all tooth contacts during chewing, swallowing, or other normal jaw movement.

What are the two guidance systems of dynamic occlusion?

The posterior guidance system (the temporomandibular joint) and the anterior guidance system (provided by the canines during lateral excursion).

What is the difference between functional and parafunctional contacts?

Functional contacts are normal contacts made during chewing and swallowing; parafunctional contacts are abnormal or deviated functions, such as clenching or bruxism.

What is trauma from occlusion?

Trauma to the periodontium caused by occlusal or parafunctional forces that exceed the adaptive and reparative capacities of the supporting structures.

What is the difference between primary and secondary occlusal trauma?

Primary trauma results from excessive occlusal force on a tooth with normal bone support; secondary trauma results from normal or abnormal forces on a tooth with inadequate bone support due to bone loss.

What is fremitus?

Movement of a tooth subjected to dynamic or functional occlusion, assessed by palpating the buccal aspect of the tooth as the patient taps up and down.

What is the G.V. Black classification system based on?

The surfaces of the teeth affected by carious lesions or restorations (Classes I through VI).

What is the key difference between G.V. Black's classification and the ICCMS/ICDAS system?

Black's system is a location-based, surgical approach describing where a lesion is; ICCMS/ICDAS stages caries by severity (sound, initial, moderate, extensive) to support early detection and remineralization.

What is the difference between attrition, abrasion, erosion, and abfraction?

Attrition is tooth-to-tooth wear; abrasion is mechanical wear from an outside object or substance; erosion is chemical loss of tooth structure from acid; abfraction is loss from flexural stress/microfracturing, typically at the cervical area.

What is a noncarious cervical lesion (NCCL)?

A lesion resulting from loss of tooth structure near the cementoenamel junction that is not related to dental caries, typically wedge-shaped and at least 1 mm deep.

What are the two basic types of pulp vitality testing?

Thermal testing and electric testing.

What is the purpose of an interocclusal record (bite registration)?

To relate the maxillary and mandibular study models to each other correctly, especially when conditions like open bite or crossbite prevent direct occlusion of the models.

What is early childhood caries (ECC)?

One or more decayed, missing, or filled primary tooth surfaces in a child younger than 6 years, often beginning as white spot lesions on the maxillary anterior teeth.

What is root caries, and what other names is it known by?

A soft, progressive lesion of the cementum and dentin near the cementoenamel junction after gingival recession exposes the root; also called cemental, cervical, or radicular caries.