scholarly journals Evaluation of the postoperative stability of a counter-clockwise rotation technique for skeletal class II patients by using a novel three- dimensional position-posture method

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Zhuqing Wan ◽  
Steve Guofang Shen ◽  
Haijun Gui ◽  
Peng Zhang ◽  
Shunyao Shen

Abstract The aim of this study is to evaluate the postsurgical stability of skeletal class II patients after performing a counter-clockwise rotational (CCWR) procedure for the maxilla-mandibular complex (MMC) by using a novel Three-dimensional (3D) Position-Posture(P-P) measuring method. Twenty-five patients (5 males and 20 females) were included in this study. The postoperative CT scans of the skull were taken before surgery(T0), 3–7 days (T1), 3 months (T2), and 6 months (T3) after surgery. Specific anatomic landmarks were chosen to determine the position of the segments, while three equally perpendicular planes were created to describe their posture. The results show that the linear relapse of maxillary landmarks during the follow-up were acceptable (≤0.5 mm). The relapse of maxillary pitch plane at 6-months follow-up is 1.52°, which is acceptable. There was a significant pitch plane relapse of the mandibular-body segment with an average of 1.86° between T1 and T2 models, 3.28° between T1 and T3 models. There was no significant difference between roll and yaw planes during the follow-up. We therefore conclude that the P-P method could be used to accurately analyze the postsurgical stability of skeletal class II orthognathic surgery cases. For CCWR procedures, it was also shown that the there is a tendency for recurrence most specially on the body of the mandible.

2018 ◽  
Vol 89 (2) ◽  
pp. 312-316
Author(s):  
Jintao Xu ◽  
Ruonan Sun ◽  
Linna Wang ◽  
Xiaoying Hu

ABSTRACT Objectives: To test the null hypothesis that there is no significant difference in pharyngeal airway space among adult skeletal Class II patients with different condylar positions using cone-beam computed tomography (CBCT). Materials and Methods: The CBCT records of 60 patients with skeletal Class II malocclusion (ANB angle ≥ 4°, Wits ≥ 0) were selected from the CBCT database. According to the condyle position, the patients were divided in three groups: anterior group (CD ≤ −12%), centric group (−12% ≤ CD ≤ +12%), and posterior group (CD ≥ +12%). Three-dimensional (3D) pharyngeal airway models were reconstructed using InvivoDental software 5.1.3. The volume and area of the pharyngeal airway space were measured in the 3D airway model. Results: The volume and area of the pharyngeal airway space in the centric group were significantly smaller than those in the posterior group (P < .01). The volume and area of the pharyngeal airway space were smallest in the anterior group and significantly increased in the centric and posterior groups (P < .001). Conclusions: The null hypothesis was rejected. Significant differences were noted in pharyngeal airway space among adult skeletal Class II patients with different condylar positions.


Scanning ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Qiang Dong ◽  
HaoYu Shi ◽  
Qi Jia ◽  
Yueyi Tian ◽  
Keqian Zhi ◽  
...  

This study was aimed at determining the three-dimensional differences in the mandible morphology between skeletal class I and II patients, at exploring the pathogenic mechanisms and morphological characteristics of skeletal class II, and at providing clinical references. The subjects were assigned to two groups according to the size of ANB angle: skeletal class I ( 2 ° < ANB   angle < 5 ° ) and skeletal class II ( 5 ° < ANB   angle < 8 ° ). After cone-beam computed tomography (CBCT) scanning, 31 landmarks and 25 measurement items were determined by In Vivo Dental 5.1 software (Anatomage, CA) for statistical analysis. The results were as follows: Co-Go, Go-Me, and CdM-CdD in skeletal class II cases were smaller than those in skeletal class I, and GoR-Me-GoL, GoR-Me-CoL, and, Ig-Men were larger than those in skeletal class I cases. In conclusion, there were significant differences in the three-dimensional morphology of the mandible between skeletal class I and class II patients. The vertical growth of the ramus, the horizontal growth of the mandibular body, and the condyle in skeletal class II patients were smaller than those in skeletal class I cases. In skeletal class II, the growth of the anterior part of the mandible in the vertical direction was larger than that in skeletal class I, and the shape of the mandible was more extended.


2018 ◽  
Vol 89 (3) ◽  
pp. 505-517. ◽  
Author(s):  
Tung Nguyen ◽  
Eui Seon Baek ◽  
Soonshin Hwang ◽  
Kyung-Ho Kim ◽  
Chooryung J. Chung

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.


2015 ◽  
Vol 86 (2) ◽  
pp. 292-305 ◽  
Author(s):  
Sherif A. Elkordy ◽  
Amr M. Abouelezz ◽  
Mona M. Salah Fayed ◽  
Khaled H. Attia ◽  
Ramy Abdul Rahman Ishaq ◽  
...  

ABSTRACT Objective:  To detect three-dimensionally the effects of using mini-implant anchorage with the Forsus Fatigue Resistant Device (FFRD). Materials and Methods:  The sample comprised 43 skeletal Class II females with deficient mandibles. They were randomly allocated into three groups: 16 patients (13.25 ± 1.12 years) received FFRD alone (Forsus group), 15 subjects (13.07 ± 1.41 years) received FFRD and mini-implants (FMI group), and 12 subjects (12.71 ± 1.44 years) were in the untreated control group. Three-dimensional analyses of cone beam computed tomographic images were completed, and the data were statistically analyzed. Results:  Class I relationship and overjet correction were achieved in 88% of the cases. None of the two treatment groups showed significant mandibular skeletal effects. In the FMI group, significant headgear effect, decrease in maxillary width, and increase in the lower facial height were noted. In the FMI group, retroclination of maxillary incisors and distalization of maxillary molars were significantly higher. Proclination and intrusion of mandibular incisors were significantly greater in the Forsus group. Conclusions:  FFRD resulted in Class II correction mainly through dentoalveolar effects and with minimal skeletal effects. Utilization of mini-implant anchorage effectively reduced the unfavorable proclination and intrusion of mandibular incisors but did not produce additional skeletal effects.


2021 ◽  
Vol 10 (9) ◽  
pp. 562-566
Author(s):  
Monika M. Ahuja ◽  
Ranjit H. Kamble ◽  
Sunita Shrivastava ◽  
Navjeet S. Gurudatta ◽  
Pooja S. Bidwai ◽  
...  

BACKGROUND Palatine rugae are small transverse structures present in the anterior 2 / 3rd of the palate. These rugae are protected by various structures of the oral cavity. They are immovable structures but variations in the oral cavity may lead to alterations in these small structures. There have been many studies that have quoted changes in these rugae patterns with various tooth movements whereas various other studies demonstrate no significant changes. None of the studies in specific have mentioned about palatal rugae changes with myofunctional appliances. The objective of this research was to evaluate the palatal rugae morphology and its stability after myofunctional therapy, as expansion and movement of teeth might lead to changes in these rugae. METHODS A total of 90 maxillary casts, 30 of Class I, 30 of Class II pre-treatment and casts of same subjects after myofunctional therapy, patients age ranging between 10 and 13 years were selected for the study. Length, intermedial and interlateral distances, angle of divergence and position of rugae were studied based on Lysell Classification 1955 and Thomas and Kotze Classification 1983. RESULTS Secondary and fragmentary rugae were found to be statistically significant as they were increased in Class II samples compared to Class I. The rugae in Class II samples were found to be shorter and therefore significant results were seen. IM1, IM2, IM4, IM5 and IM6 were found to be statistically significant respectively. Similarly, IL2, IL4, IL5 and IL6 were appreciable. IM1 was found to be appreciable. IL1, IL2, IL3 and IL4 were statistically significant. Significant difference was found in mean rugae value among Class I and Class II pre-treatment groups. Statistically significant difference was found in mean rugae value among Class I and Class II pre-treatment group. Incisive papilla to posterior border of last rugae (IP-PBA) was found to be statistically significant. CONCLUSIONS Myofunctional therapy did have an effect on the rugae pattern. But the age group of 10 – 13 years consisted of growing individuals. Therefore, it could not be concluded as to whether the changes were because of growth taking place or because of myofunctional therapy. KEY WORDS Palatine Rugae, Myofunctional Appliances, Class II Malocclusion


2007 ◽  
Vol 77 (5) ◽  
pp. 870-874 ◽  
Author(s):  
Roberto M. A. Lima Filho ◽  
Antonio C. O. Ruellas

Abstract Objective: To evaluate a 10-year follow-up of anteroposterior and vertical maxillary changes in skeletal Class II patients treated with slow and rapid maxillary expansion methods. Materials and Methods: The sample consisted of 70 patients divided into two groups: (1) treated with a cervical headgear with expansion of the inner bow (CHG) and (2) using a Haas-type rapid maxillary expansion appliance in conjunction with cervical headgear (RME-CHG). The CHG group consisted of 40 patients (18 males and 22 females; average age 10.6 years at pretreatment [T1], 13.6 years at posttreatment [T2], and 23.6 years at postretention [T3]). The RME-CHG group consisted of 30 patients (14 males and 16 females; average age 10.4 years at T1, 14.0 years at T2, and 24.6 years at T3). The profiles of SNA and SN-PP angles showed no significant differences in either group at T1, T2, and T3 phases. Results: For the entire sample, the profile analysis between the phases showed reduction in the SNA angle from T1–T2 and an increase from T2–T3. The SN-PP angle showed an increase from T1–T2 and a decrease from T2–T3. Treatment of skeletal Class II patients with slow and rapid maxillary expansions was efficient and stable over the long-term. Conclusions: The profiles of SNA and SN-PP at T1, T2, and T3 achieved with slow and rapid maxillary expansions were clinically equivalent.


2021 ◽  
Vol 15 (2) ◽  
Author(s):  
Katayoon Khaleghi ◽  
Azin Nourian ◽  
Pooya Ghorbankhan ◽  
Arash Farzan

Background: Following the morphological features of different races and ethnic groups, knowledge of standard dentofacial patterns of each ethnic group is essential. Therefore, this study aimed to explain cephalometric standards for the Zanjanian population according to Downs' analysis and compare them to Caucasian individuals. Methods: Seventy lateral cephalometries of Zanjanian adults (17 - 29 years old) who had been referred to a private orthodontic office in Zanjan, Iran with class I molar and canine relationship and normal overjet and overbite as well as minimum crowding/spacing/rotations were scanned and traced with the Novatech scanner and Dolphin software version 10. Next, statistical analyses were performed in order to compare the Zanjanian population to Caucasians. Results: We found a significant difference between males and females in terms of interincisal angle, incisor-occlusal angle, incisor-mandibular plane angle, upper incisor proclination, facial angle, and angle of convexity. Discussion: The analysis of six statistically significant parameters indicates that the upper and lower incisors in women of Zanjan were proclined and protruded compared with those of Caucasian subjects. Due to the statistical analysis on facial angle and angle of convexity, women also show more maxillary prognathism and skeletal class II pattern. Generally, a comparison of Zanjanian population cephalometrics based on Downs' analysis showed an increase in maxillary prognathism, maxillary and mandibular incisal protrusion and posterior rotation of the mandible. Conclusions: In conclusion, the Zanjanian population tends to have more dental and skeletal class II patterns than the Caucasians. In addition, gender comparison indicates lower and upper-incisors protrusion in women of Zanjan.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
G. Turatti ◽  
A. Bruni ◽  
M. Savoini ◽  
M. Giordano ◽  
G. Gerbino

Aim. To describe a multidisciplinary treatment to correct a severe II class malocclusion with reduced both maxillary and mandibular transverse dimensions and dental crowding. Case Report. A 17-year-old young woman presented with an increased overjet complaining chiefly of forwardly placed upper front teeth and unpleasant smile aesthetics. The patient facially exhibited a gently convex profile, severe mentalis strain on lip closure, and dark buccal corridors. The intraoral assessment indicates Class II molar relationship bilaterally, mandibular and maxillary anterior crowding, and narrow shape of upper and lower arches. The cephalometric evaluation of the lateral radiograph of the skull evidences a skeletal Class II with a reduction of lower face height. Based upon the diagnostic records and consultation with the patient, surgically assisted expansion of both arches using bone-borne distractors, comprehensive orthodontic treatment, and combined jaw surgery was planned. Results. This approach permitted achieving most of the desired objectives in approximately 30 months. The follow-up records 30 months after treatment conclusion showed a stable occlusion. No complications were clinically and radiographically noticeable during the follow-up.


2021 ◽  
Author(s):  
Minjiao Wang ◽  
Hanjiang Zhao ◽  
Xiangyu Wang ◽  
Yifeng Qian ◽  
Hongbo Yu ◽  
...  

Abstract Background: To retrospectively evaluate postsurgical stability and condylar morphology for skeletal class II malocclusion patients with condylar resorption (CR) treated with orthognathic surgery.Methods: Thirty-five patients treated with combined orthodontic and orthognathic surgery between 2014 and 2018 were enrolled in this retrospective study. CT scans were acquired preoperatively (T0), 2–7 days after surgery (T1), and 1 year postoperatively (T2). The amount of mandibular advancement, postsurgical relapse, condylar morphology and joint spaces were analysed respectively. Statistical analysis was performed using R, version 3.4.3 (R Development Core Team 2010).Results: The average mandibular advancement and counter-clockwise rotation were 5.51 mm and -2.82 degrees respectively. The average relapse was 1.08 mm (19.6% of the advancement) and 1.13 degrees. The condylar volume showed a postoperative reduction of 161.86 mm3(13.7% of initial condylar volume). AJS increased after surgery and gradually returned to its original state, while SJS and PJS decreased and remained stable. Surgical advancement of B point was significantly correlated with skeletal relapse. The optimal cut-off values were as follows: MP-FH (40.75°); ramus height (51.125 mm); SJS (1.63 mm); surgical displacement (4.72 mm); CCR (-4.3°); AJSC (1.07 mm).Conclusions: Skeletal class II patients with CR have a high risk of postsurgical condylar resorption, which was most related to nonsurgical risk factors such as gender(female) and condylar angle. Condylar had moved posteriorly to the concentric position after surgery and remained quite stable through the 1-year follow-up. Preoperative skeletal patterns such as lower ramus height and surgical procedures such as larger advancement of the mandible were closely associated with sagittal relapse of the mandible.


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