Occlusion Condition n * % [CI.sub.95%] Canines' Key Class I 5,255 77.1 76.1-78.1 Class II 1,110 16.3 15.4-17.2 Class III 451 6.6 6.0-7.2 Overjet Normal 4,214 67.1 65.9-68.3 Augmented 1,432 22.8 21.8-23.8 Top-to-top 438 7.0 6.3-7.6 Anterior crossbite
196 3.1 2.7-3.6 Overbite Normal 4,085 65.4 64.2-66.6 Reduced 795 12.7 11.9-13.6 Open 696 11.1 10.4-11.9 Deep 673 10.8 10.0-11.5 Back crossbite Absence 5,532 81.3 80.3-82.2 Presence 1,276 18.7 17.8-19.7 Malocclusion Absent 2,523 36.8 35.7-38.0 Present 4,332 63.2 62.1-64.3 * Totals vary due to lack of information.
Thirty patients (15 males and 15 females) were selected from September 2014 to August 2017 in the Department of orthodontics, Shanxi Medical University Stomatological Hospital.Inclusion criteria: 1) ages: 6-10 years; 2) skeletal class III malocclusion; 3) mesial molars relationship; 4) anterior crossbite
and reverse overjer.
Fu, "Electromyographic investigation of masticatory muscles in unilateral cleft lip and palate patients with anterior crossbite
," Cleft Palate Craniofacial Journal, vol.
Mandibular incisor extraction is most frequently indicated in mild or moderate Class III malocclusions with an edge-to-edge occlusion of the incisors or anterior crossbite
and minimal overbite or open bite .
Every patient that met the inclusion criteria and provided consent or whom consent was provided for underwent an oral examination and the measurement of his or her occlusal characteristics (including overjet, overbite, maxillary midline diastema, anterior crossbite
, posterior crossbite, incisor irregularity, and Angle's molar classification).
No distance between upper and lower incisors was defined as normal overjet (0 mm); increased overjet was recorded when the distance was > 2 mm, and anterior crossbite
was recorded when the distance was < 0 mm.
This is the normal overjet relationship, which ranges from 1 to 3 mm.(2) Abnormal anterior relationships include an excess overjet, edge-to-edge contact, and an anterior crossbite
in which the maxillary incisors are posterior to the mandibular incisors (figure 3).
is defined as an abnormal reversed relationship of a tooth or teeth to the opposing teeth in the buccolingual or labiolingual direction, and it is also known as reverse articulation .
Plaster models made during orthodontic initial records for each patient were used to calculate the following occlusal trait measurements: Angle's classification, maxillary overjet, mandibular overjet (reverse overjet), anterior crossbite
, posterior crossbite, scissors bite, overbite, openbite, crowding, spacing and dental midline discrepancy.