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Bimaxillary orthognathic surgery can cause changes to respiration and the airways. We used body plethysmography to evaluate its effect on airway resistance and lung volumes in 20 patients with class III malocclusions (8 men and 12 women, aged 17 - 32 years). Lung volumes (forced vital capacity; forced inspiratory volume/one second; forced expiratory volume/one second: forced vital capacity; peak expiratory flow; maximum expiratory flow 25-75; maximum inspiratory flow; total lung capacity; residual volume; residual volume:total lung capacity), and airway resistance were evaluated one week before, and six months after, operation. Bimaxillary operations to correct class III malocclusions significantly increased airway resistance, residual volume, total lung capacity, and residual volume:total lung capacity. Other variables also changed after operation but not significantly so. Orthognathic operations should be done with caution in patients who have pre-existing respiratory diseases. [ABSTRACT FROM AUTHOR]

Bone-anchored maxillary protraction (BAMP) is effective for skeletal Class III malocclusion. However, infection, screw and plate loosening, and device failures occur with conventional plates. This pilot prospective study analyzed the feasibility of individualized BAMP using preoperative simulation and 3D titanium printing in patients referred by the orthodontic department for four BAMP miniplates. Preoperative cone beam computed tomography data were analyzed using CAD/CAM software to fabricate the individualized 3D-printed BAMP device. The customized plates were printed using selective laser sintering and inserted onto the bone through an adjunct transfer jig. The accuracy of preoperative simulation and actual placement of the BAMP device were tested by superimposing simulated positioned digital images and postoperative computed tomography data. The growth modification effect depended on superimposition of lateral cephalograms and comparative changes in SNA, SNB, ANB, and Wits. Two male patients were finally included in the study. BAMP decreased the ANB difference (−4.56 to −1.09) and Wits appraisal (−7.52 to −3.26) after 2 years. Normal measurement indices for sagittal and vertical growth indicated successful growth modification. The mean accuracy between preoperative simulation and actual surgery was 0.1081 ± 0.5074 mm. This treatment modality involving preoperative simulation and 3D titanium printing for fabricating and placing customized BAMP devices precisely at planned locations is effective for treating skeletal Class III malocclusion. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the effects of very early face mask therapy in children with Class III malocclusion. At pretreatment (T0), 40 female subjects who were eventually treated showed a more severe Class III pattern (ANB 0.1°) than did 28 skeletal Class III female subjects who remained untreated (ANB 0.4°), as observed in the Wits analysis. Posttreatment results (T1) showed significant (p<0.01) anterior advancement of the maxillary components, backward rotation of the mandible without increased lower anterior facial height, and an improved incisor relationship. Comparison of posttreatment (T1) and postretention (T2) records, however, revealed no increase in SNA in the treated group. SNA did increase in the untreated group, with no significant difference in ANB angle. The x-components of B-point and Me showed a significant (p<0.05) difference between the two groups. At postretention (T2), N-S-Ba, N-S-Ar, and CC-Ba tended to increase more in the treated group than in the untreated group. [ABSTRACT FROM AUTHOR]

A skeletal Class III malocclusion with open bite tendency is considered very difficult to treat orthodontically without surgery. This case report describes the lingual orthodontic treatment of an adult skeletal Class III patient with mandibular deviation to the left side, lateral open bite, unilateral posterior crossbite, zero overbite and negative overjet. The lower incisors were already retroclined to compensate with the skeletal discrepancy. The patient was treated by asymmetric molar extraction in the mandibular arch to retract the lower incisors and correct the dental midline, with the help of intermaxillary elastics. Lingual appliance was used with over-torqued lower anterior teeth's brackets to control the torque of mandibular incisors. After a 30-month treatment, satisfactory smile and facial esthetics and good occlusion was achieved. A 12-month follow-up confirmed that the outcome was stable. Asymmetric molar extraction could be a viable option to retract mandibular incisors in Class III malocclusion with lower dental midline deviation.

Objective: To investigate the effect of bilateral sagittal split ramus osteotomy (BSSRO) on temporomandibular joint (TMJ) symptom and condylar position in patients with skeletal class Ⅲ malocclusion treated with orthodontic-orthognathic surgical treatment., Methods: Twenty-four patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment were included in the study. Their cone-beam computed tomography scans and TMJ symptom were evaluated, and their Helkimo index before BSSRO, 1 month after BSSRO, and 12 months after BSSRO was recorded. The maximum diameter of the horizontal and coronal sections, short axis diameters, neck width, height, joint space widths at different angles (45°, 90°, and 135°) of the condylar joint, bilateral condylar spacing, and different condylar angles (horizontal angle, vertical angle, and stress angle) in three dimensions were measured. Then, the changes in TMJ symptom and bone structure at different periods were analyzed., Results: The Helkimo index was anamnestic (Ai) or dysfunctional (Di) levels 0 or 1 before and after BSSRO, and no difference in Helkimo index was observed. The horizontal angle and joint space widths at 45° and 90° increased whereas the joint space width at 135° decreased at 1 month after BSSRO compared with before BSSRO (P<0.05). Except for the increase in condylar horizontal angle (P<0.05), no significant difference in other measurement items was noted (P>0.05) 12 month after BSSRO., Conclusions: BSSRO would not have a remarkable effect on the TMJ symptom and condylar position of patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment procedure and whose Helkimo index ranked Ai0, Ai1, Di0, and Di1.

Objective: This study aimed to investigate the therapeutic effects and advantages of skeletal class Ⅲ malocclusion treatment by transmission straight wire technique., Methods: Ninety-seven patients who received treatment for skeletal class Ⅲ malocclusion at the Department of Stomatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2012 to January 2017 were selected for this retrospective study. All these patients refused surgery. They were divided into two groups in accordance with the type of skeletal malocclusion: mild-to-moderate skeletal malocclusion group (-4°≤ANB <0°) and severe skeletal malocclusion group (-8°≤ANB<-4°). Each of the two groups was divided further into two small groups in accordance with the technique used: T group (transmission straight wire technique) and M group (MBT technique)., Results: The crossbite of all 59 patients in the mild-to-moderate skeletal malocclusion group was successfully treated. The molars were classified as classⅠrelationship, and the facial profile improved. Significant differences were found in the values of U1/SN angle, L1/MP angle, and Lip-Diff between the T and M groups before and after the treatment (P<0.05). The extent of incisor root resorption was lighter in the T group than in the M group (P<0.05). In the severe skeletal malocclusion group, the crossbite of all 38 patients was cured or partially cured. Fourteen patients showed severe lower anterior teeth inclination (five in the T group and nine in the M group), and the profiles did not significantly improve. Significant differences were observed in the values of U1-NA value, U1/SN angle, L1-NB value, L1/MP angle, LLP, and Lip-Diff between the T and M groups before and after the treatment (P<0.05). The extent of incisor root resorption was lighter in the T group than in the M group (P<0.05)., Conclusions: Relative to the MBT technique, the transmission straight wire technique has great advantages in improving facial profile, reducing the compensatory inclination of the upper and lower anterior teeth, and reducing the risk of root resorption in the treatment of skeletal class Ⅲ malocclusion.

The article presents a case study of a 11-year-old boy presented with chief complaint of anterior crossbite and radiographic examination of lateral cephalogram indicate Frankfurt Mandibular plane Angle (FMA) with short maxillary jaw base length and correction of orthodontics.

Objective: To assess the efficacy of bone anchorage and maxillary facemask protraction devices in treating skeletal class Ⅲ malocclusion in adolescents., Methods: Articles relating to the use of bone anchorage and maxillary facemask protraction devices for treating skeletal class Ⅲ malocclusion in adolescents were searched from the databases of Cochrane Library, PubMed, EmBase, CNKI, and Wanfang database. Several inclusion and exclusion criteria were developed for the article screening. The clinical data were extracted, and the quality of the selected articles was evaluated. A Meta-analysis of SNA, SNB, ANB, ANS-Me, Wits, and U1-PP change was performed by using RevMan 5.3., Results: Seven studies (264 patients) were included in the Meta-analysis. Among these studies, three were randomized controlled trials, and four were non-randomized controlled trials. Compared with the maxillary facemask protraction device group, the bone ancho-rage device group had higher SNA changes and lower ANS-Me, Wits, and U1-PP changes (P<0.05). No significant differences were observed in the SNB and ANB changes between these two groups., Conclusions: Compared with the maxillary facemask protraction device, the bone anchorage device can increase the extent of protraction of the maxilla and has better controls for the labial inclination of the maxillary anterior teeth in treating skeletal class Ⅲ malocclusion among adolescents. However, additional high-quality randomized controlled trials must be performed to verify the results.

Ideally, orthognathic surgery is indicated to treat skeletal Class III malocclusion with severe open bite in adults. In this borderline case, however, camouflage treatment without any skeletal anchorage was chosen. This report describes the orthodontic treatment of a 23-year-old man who presented with multiple orthodontic problems including severe open bite of the anterior and posterior teeth up to the first molars, bilateral posterior crossbite, bilateral Class III molar relationship, severe crowding, increased vertical dimension, and dental and facial midline deviation. The treatment included the extraction of four wisdom teeth, uprighting and distalisation of the mandibular arch with molar intrusion using curved NiTi wires with intermaxillary elastics. After 36 months of treatment, satisfactory improvements in the vertical overlap, horizontal overlap and sagittal malocclusion were achieved. The design of the mechanical system used in this case confirmed stable results at the 4-year follow-up.

Objective: To investigate the effect of pre-surgical orthodontic treatment on temporomandibular joint (TMJ) in patients with skeletal class Ⅲ malocclusion treated with orthodontic-orthognathic surgical treatment., Methods: Twenty-four patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment were included in the study. Before and after the completion of orthodontic treatment, the symptoms of TMJ were examined and recorded, and the short- and the long-axis diameter of the condylar (d), condylar height (h), joint space (L) at different angles, bilateral condylar spacing (R), and the condylar angles were measured, with scanning performed by using cone-beam computed tomography (CBCT). Then, the changes of TMJ symptoms and bone structure at different periods were analyzed., Results: No significant changes were observed in the joint symptoms before and after the pre-surgical orthodontic treatment. No significant changes were found in the measurements of the bone structure of TMJ in the dimensional direction (P>0.05)., Conclusions: In the orthodontic-orthognathic surgical treatment procedure, the pre-surgical orthodontic process does not have a significant effect on TMJ.

Objective: To evaluate the prevalence of periodontal biotypes in patients with skeletal Class III malocclusion and to explore its association with age, gender, other periodontal clinical parameters and width of keratinized gingiva (WKG)., Methods: Data were collected for the buccal-middle site of 310 anterior teeth from 26 subjects who received periodontally accelerated osteogenic orthodontics (PAOO) surgery before orthodontic treatment. Univariate and multivariate analysis were performed to calculate and test the correlations between periodontal biotype and age, gender and bleeding index (BI), gingival recession (GR), plaque index (PLI), probing depth (PD) and WKG., Results: Prevalence of thin periodontal biotype was 33.9% in the anterior region. Mean WKG was 4.37 mm. Univariate analysis showed that a moderately positive correlation was found between WKG and thick biotype (r = 0.544, P < 0.001). A low positive correlation was detected between mandibular teeth and thick biotype (r = 0.387, P < 0.001) and a low negative correlation was detected between GR and thick biotype (r = -0.308, P < 0.001). Multi-level logistic regression showed that biotype was significantly associated with dental arch (odds ratio [OR] = 0.174, P = 0.015) and WKG (OR = 2.043, P = 0.002). No significant associations were detected between biotype and other factors., Conclusion: Dental arch and WKG were associated with periodontal biotype in patients with skeletal Class III malocclusion.

Objective: The purpose of this study was to analyze the transverse dental compensation in reference to the maxillary and mandibular basal bones using cone-beam computed tomography (CBCT) and evaluate the correlations between transverse dental compensation and skeletal asymmetry variables in patients with skeletal Class III malocclusion and facial asymmetry., Methods: Thirty patients with skeletal Class I (control group; 15 men, 15 women) and 30 patients with skeletal Class III with menton deviation (asymmetry group; 16 men, 14 women) were included. Skeletal and dental measurements were acquired from reconstructed CBCT images using OnDemand3D 1.0 software. All measurements were compared between groups and between the deviated and nondeviated sides of the asymmetry group. Correlation coefficients for the association between skeletal and dental measurements were calculated., Results: Differences in the ramus inclination ( p < 0.001), maxillary canine and first molar inclinations ( p < 0.001), and distances from the canine and first molar cusp tips to the midmaxillary or midmandibular planes ( p < 0.01) between the right and left sides were significantly greater in the asymmetry group than in the control group. In the asymmetry group, the ramus inclination difference ( p < 0.05) and mandibular canting ( p < 0.05) were correlated with the amount of menton deviation. In addition, dental measurements were positively correlated with the amount of menton deviation ( p < 0.05)., Conclusions: Transverse dental compensation was correlated with the maxillary and mandibular asymmetry patterns. These results would be helpful in understanding the pattern of transverse dental compensation and planning surgical procedure for patients with skeletal Class III malocclusion and facial asymmetry., Competing Interests: CONFLICTS OF INTEREST: No potential conflict of interest relevant to this article was reported.

Objective: To evaluate vertical stability after various orthognathic surgical treatment plans for skeletal class Ⅲ malocclusion with anterior openbite., Methods: A retrospective multicenter cohort study was conducted to investigate vertical stability after various orthognathic surgical treatment plans for skeletal class Ⅲ malocclusion with anterior openbite. From 2010-2016, 122 patients from two domestic stomatological hospitals were included in our study. Patients were divided into four groups according to their treatment plans, namely, bilateral sagittal split ramus osteotomy (BSSRO), intraoral vertical ramus osteotomy (IVRO), BSSRO+Le Fort Ⅰ, and IVRO+Le Fort Ⅰ. All patients followed a standardized examination procedure at 6 and 24 months post-treatment. The observation indexes include overbite, mandibular plane angle, and intermaxillary angle., Results: 1) The significantly reduced ratio of the overbite in the BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than the BSSRO and IVRO groups at 6 and 24 months post-treatment. 2) The significantly increased ratio of the mandibular plane in BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than BSSRO and IVRO groups at 6 and 24 months post-treatment. 3) The significantly increased ratio of the intermaxillary angles in BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than the BSSRO and IVRO groups at 6 months post-treatment, while there was no statistical difference at 24 months post-treatment., Conclusions: Bimaxillary surgery (BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ) is more effective than mandibular surgery to control vertical relapse.

This study is to use cone beam computed tomography (CBCT) to acquire accurate radiographic images for alveolar bone in lower incisors and the change after presurgical orthodontic treatment. Seventeen patients with skeletal Class III malocclusion, ten normal occlusion subjects, and fifteen patients treated with orthodontic treatment and orthognathic surgery were included. CBCT images were obtained. The labial and lingual inclinations of mandibular incisors, the thickness of alveolar bone, the vertical alveolar height and root length were measured. Alveolar bone thickness at the apex in patients with skeletal Class III malocclusion was thinner than normal subjects. The vertical alveolar bone heights at labial and lingual sides in patients with skeletal Class III malocclusion were both reduced compared with normal subjects, especially at the labial side. There were statistically significant correlations between lower incisor inclination and alveolar bone morphology. After orthodontics, the incisors root apex was closer to the lingual side of alveolar bone. The alveolar bone thickness at apex was not statistically changed. The vertical alveolar bone heights at the labial and lingual sides were both significantly reduced especially the lingual side after presurgical orthodontic treatment. The root length was not significantly changed. In conclusion, the alveolar bone thickness at apex is thinner and the vertical alveolar height is reduced at the labial side. Forward movement of lower incisors during presurgical orthodontic treatment can render the lower incisors root apex closer to the lingual side and the vertical alveolar height is reduced.

This article presents a case of class III malocclusion, a female patient aged 8 years treated in early stage of its recognition, i.e. treated in early mixed dentition stage, utilizing orthopedic appliance for its correction, utilizing both rapid maxillary expansion and face mask approach. After the skeletal base correction as part of phase of phase I therapy, a retentive plate was given and patient was asked to report every 6 months for review and monitoring of her growth pattern and phase II treatment planning after the eruption of all permanent teeth. How to cite this article: Khan MB, Karra A. Early Treatment of Class III Malocclusion: A Boon or a Burden? Int J Clin Pediatr Dent 2014;7(2):130-136.