Three-dimensional observations of the effects of third molars on orthodontic treatment

Some adult cleft palate patients show severe maxillary transverse contraction and posterior crossbite. This case report demonstrates successful surgical-orthodontic treatment of such a patient. Surgically assisted rapid maxillary expansion (SA-RME) was completed prior to comprehensive orthodontic treatment. The osteotomy was performed on both the buccal and lingual aspects of the posterior maxillary alveolus. A Hyrax-type maxillary-expansion appliance was used, and the screw (0.2 mm, one quarter turn) was turned two or three times per day. Comprehensive orthodontic treatment was initiated after extraction of the mandibular first premolars and four third molars. The maxillary lateral incisors were also extracted after active orthodontic treatment. The amount of expansion achieved using SA-RME was greater at the posterior than at the anterior maxilla. Midpalatal suture opening occurred. After orthodontic treatment, occlusal stability was satisfactory. This case demonstrates the effectiveness of SA-RME in adult cleft palate patients with severe posterior crossbite.

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Highly variable rate of orthodontic tooth movement measured by a novel 3D method correlates with gingival inflammation

Clinical Oral Investigations ◽

10.1007/s00784-020-03502-2 ◽

2020 ◽

Author(s):

Marc A. de Gouyon Matignon de Pontouraude ◽

Johannes W. Von den Hoff ◽

Frank Baan ◽

Robin Bruggink ◽

Marjon Bloemen ◽

...

Keyword(s):

Biological Markers ◽

Orthodontic Treatment ◽

Tooth Movement ◽

Gingival Crevicular Fluid ◽

Contact Point ◽

Anterior Segment ◽

Three Dimensional ◽

Orthodontic Tooth Movement ◽

Large Individual ◽

Gingival Inflammation

Abstract Objectives Individual orthodontic treatment duration is hard to predict. Individual biological factors are amongst factors influencing individual rate of orthodontically induced tooth movement (OTM). The study aim is to determine the rate of OTM by a novel 3D method and investigate parameters that may predict the rate of tooth movement. Materials and methods In this prospective cohort study, rate of OTM was determined from 90 three-dimensional intra-oral scans in 15 patients (aged 12–15) undergoing orthodontic treatment. For each patient, intra-oral scans were taken every week for up to 6 weeks (T0–T5). The teeth were segmented from the scans and the scans were superimposed on the palatal rugae. The rate of OTM was calculated for each tooth. Other parameters were gingival inflammation, contact-point displacement and the biological markers, matrix metalloproteinases (MMP), MMP-9 and MMP-2 in gingival crevicular fluid (GCF). Results Our study showed a high variation in the rate of OTM, varying from 0.15 to 1.24 mm/week. Teeth in the anterior segment tended to move more compared with the posterior segment. The contact point displacement and gingival inflammation varied greatly amongst the patients. The MMPs measured did not correlate with tooth movement. However, the gingival inflammation index showed a significant correlation with OTM. Future studies should include other biological markers related to bone-remodeling. Conclusion This novel and efficient 3D method is suitable for measuring OTM and showed large individual variation in rate of OTM. Clinical relevance Patients show different rates of OTM. The rate of OTM in an individual patient can provide guidance in timing of follow-up appointments.

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Investigation of third molar impaction in Turkish orthodontic patients: Prevalence, depth and angular positions

European Journal of Dentistry ◽

10.4103/1305-7456.119084 ◽

2013 ◽

Vol 07 (S 01) ◽

pp. S094-S098 ◽

Cited By ~ 13

Author(s):

Ahu Topkara ◽

Zafer Sari

Keyword(s):

Gender Bias ◽

Orthodontic Treatment ◽

Chart Review ◽

Angular Position ◽

Third Molar ◽

Third Molars ◽

Related Data ◽

Digital Database ◽

Orthodontic Patients ◽

University Department

ABSTRACT Objective: We aimed to investigate the prevalence, distribution, angular position, and depth of third molar impaction in a Turkish orthodontic patient population. Materials and Methods: We retrospectively reviewed the panoramic radiographs, intraoral photographs, and dental casts of 207 patients (62 men and 145 women; age 20-39 years) who had undergone orthodontic treatment at a university department of orthodontics for impacted third molars (ITMs). A comprehensive chart review of all subjects was conducted. Patient and treatment-related data were recorded in a digital database for comparative analysis. Results: The prevalence of ITMs was 54.1%, and no statistically significant gender differences were evident (61.3% in men and 51.0% in women; P = 0.23). The frequency of maxillary ITMs was 49.3% (148 of 300 teeth) while that of mandibular ITMs was 50.7% (152 of 300 teeth). The most frequently observed angulations of impaction were mesioangular for the mandible (65.1%), and distoangular for the maxilla (64.2%). Of all the ITMs analysed, 61% were partially buried in bone and 39% were completely buried. Conclusions: Third molar impaction was evident in 54.1% of a group of Turkish orthodontic patients aged 20-39 years, and there was no statistically significant gender bias. Mesioangular and distoangular inclinations were the most common in the mandible and the maxilla, respectively.

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Nonsurgical and nonprosthetic camouflage treatment of skeletal Class II open bite with bilaterally missing lower first molars

The Angle Orthodontist ◽

10.2319/030718-189.1 ◽

2018 ◽

Vol 89 (3) ◽

pp. 505-517. ◽

Cited By ~ 1

Author(s):

Tung Nguyen ◽

Eui Seon Baek ◽

Soonshin Hwang ◽

Kyung-Ho Kim ◽

Chooryung J. Chung

Keyword(s):

Treatment Outcome ◽

Three Dimensional ◽

Class Ii ◽

Open Bite ◽

Third Molars ◽

Second Molar ◽

Skeletal Class ◽

Long Term Stability ◽

Skeletal Class Ii

ABSTRACT This report illustrates the successful nonsurgical and nonprosthetic camouflage treatment of a skeletal Class II open bite malocclusion combined with missing mandibular first molars bilaterally. In the mandible, the second and third molars were uprighted and protracted, substituting for the missing first molars. In the maxilla, anterior bodily retraction and full-arch intrusion were achieved following premolar and second molar extraction, which also induced autorotation of the mandible. The treatment outcome and prognosis were confirmed with three-dimensional superimposition techniques, along with long-term stability.

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