OBJECTIVEThis study aims to analyze the long-term stability of the anterior teeth and hard tissue of skeletal class III malocclusion after a three-year orthodontic surgery by systematic review.

METHODSAll studies about skeletal class III malocclusion with orthodontic-surgery were searched by computer-based retrieval and manual retrieval; the deadline is December 2013. The literature, filtered according to the inclusion criteria and exclusion criteria, was performed with quality. assessment. The same indicators of the anterior location and hard tissue stability were combined and evaluated with metaanalysis and descriptive analysis by Rev Man5.2.

RESULTSFour before-and-after comparison study articles with 180 cases were included. The grades of the four literature evaluation were A. The meta-analysis results showed that comparing the three-year post-orthodontic-surgery and post-orthodontic-surgery, the total weighted mean difference (WMD) of Ul-SN was 4.29 (P<0.05); the WMD of Ll-MP, OB, OJ, SNA, SNB, ANB, and MP-SN were -1.58, 0, -0.41, -0.58, 0.25, -0.70, and 0.39, respectively (P>0.05). The measurement methods of A and B point position were different, hence the qualitative description were as follows: point A remained at a relatively stable position, and point B had some replacement compared with post-operative (P<0.05).

CONCLUSIONTo the skeletal class III malocclusion after three-year orthodontic-surgery, the position of the lower anterior teeth could be kept stable, as well as the overbite and the overjet of the anterior teeth; only the upper inci- sor has a lip-inclined relapse. The maxillary could also be kept stable, and the mandibular had a little relapse.

Cephalometry ; Humans ; Malocclusion, Angle Class III ; surgery ; Mandible ; Maxilla ; Overbite

malocclusion with Angle Class III patients. We asessed the soft tissue changes according to skeletal changes of patients who have undergone orthognathic surgery with bilateral split sagittal ramus osteotomy (BSSRO) and advancing genioplasty. MATERIALS & METHODS: The soft tissue change of 9 skeletal Class III patients was assessed after BSSRO and advancing genioplasty. The patient group was skeletal Class III who was surgically treated by BSSRO & advancing genioplasty. The average follow up period is 13 months with the range of 6 and 30 months. All patients have undergone preoperative and postoperative orthodontic treatment. The assessment was devided into two groups. One was antero-posterior relationship and the other was vertical relationship of dimensional changes of soft tissue after orthognathic surgery. RESULTS: In antero-posterior dimensional changes after surgery, the percentage of soft tissue change in comparison to hard tissue was 89%. Vertical ratio after surgery , 86% soft tissue changes were assessed.]]>
Clinical Protocols ; Follow-Up Studies ; Genioplasty ; Humans ; Malocclusion ; Malocclusion, Angle Class III ; Orthognathic Surgery ; Osteotomy

Orthognathic surgery has been used regularly to treat dentofacial deformities. The surgical procedures affect both the facial appearance as well as the posterior airway space (PAS). Our current literature indicates that setback procedures produce an inferior repositioning of the hyoid bone and posterior displacement of the tongue and the soft palate. These movements cause anteroposterior and lateral narrowing of the PAS. Most authors agree that these effects are permanent. The PAS changes in turn produce an adaptive posturing, with an increased craniocervical angle to open up the PAS. Even though most patients do not display snoring and obstructive sleep apnoea (OSA) post-surgery, there is certainly an increased possibility in patients with already compromised airways. Therefore, patients who are undergoing orthognathic surgery should be screened for excessive daytime somnolence, snoring, increased body mass index (BMI) and medical conditions related to OSA and sent for an overnight polysomnography (PSG) if OSA is suspected. Then the proposed treatment plan may be modified according to the risk of potential airway compromise or even to improve it. Conversely, advancement of the maxilla and mandible causes widening of the airway in both the anteroposterior and lateral dimensions. This effect would translate to better airflow and decreased airway resistance. This is supported by the evidence showing high success rates when orthognathic surgery, especially maxillomandibular advancement (MMA), is utilised to treat OSA.
Airway Obstruction ; etiology ; surgery ; Cephalometry ; Humans ; Malocclusion ; complications ; pathology ; surgery ; Malocclusion, Angle Class II ; surgery ; Malocclusion, Angle Class III ; surgery ; Mandibular Advancement ; Oral Surgical Procedures ; Osteotomy ; Treatment Outcome

OBJECTIVETo evaluate the effect of extraction and non-extraction decompensation to bimaxillary orthognathic surgery in skeletal class III malocclusion and the effect on postoperative.

METHODSRecords of 36 completed surgical-orthodontic treatment skeletal class III malocclusion patients were obtained from School of Stomatology, China Medical University, 18 underwent maxillary premolar extraction, the other 18 underwent non-extraction. Their post-decompensation and postsurgery cephalometric radiographs were analyzed objectively, and their profile scissors-shadows in different groups were evaluated subjectively.

RESULTSThe cephalometric index of post-presurgical orthodontics showed that there were significant deviations between the extraction and non-extraction groups including U1-SN, Overjet and Cm-Sn-UL values (P<0.05). During surgery, mandible was retruded (8.66 +/- 1.42) mm in extraction group compared with (6.21 +/- 3.06) mm in non-extraction group (P<0.05). After surgery, the extraction group achieved more normal ANB, U1-SN, NA-PA values (P>0.05).

CONCLUSIONMaxillary premolar extraction can make incisor decompensation more complete so that mandible can be retruded to more ideal position and concave face can be successfully corrected.

Bicuspid ; Cephalometry ; Face ; Humans ; Incisor ; Male ; Malocclusion, Angle Class III ; Mandible ; Orthognathic Surgery ; Treatment Outcome

OBJECTIVETo establish a model of cephalometric variables for identification of indication of early treatment of class III malocclusion in mixed dentition.

METHODSCephalograms taken in the mixed dentition were available for twenty-eight patients (16 males, 12 females, mean age: 9.1 +/- 1.4 years) in early treatment group and twenty-one patients (12 males, 9 females, mean age: 10.0 +/- 2.0 years) in orthognathic surgery group. Patients in early treatment group received successful treatment to correct anterior crossbites in mixed dentition and later received non-extraction comprehensive treatment in permanent dentition. Patients in orthognathic surgery group received orthognathic surgery after growth ceased.

RESULTSThe mean value of AB-MP in early treatment and orthognathic surgery groups was 65.1 degrees and 61.2 degrees, respectively (P < 0.05). The mean value of the angle between upper incisor inclination and AB line was 23.1 degrees in early treatment group and 27.3 degrees in orthognathic surgery group (P < 0.05).

CONCLUSIONSThe resulting equation was: individual score (IS) = 0.164 x (AB-MP)-0.15 x (U1-AB)-6.675. When IS > 0, greater success in early treatment of class III malocclusion in mixed dentition was expected and when IS < 0, delayed treatment with orthognathic surgery is recommended.

Cephalometry ; Child ; Dentition, Mixed ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; surgery

OBJECTIVE: To evaluate the decompensation effectiveness and alveolar bone remodeling of mandibular anterior teeth after preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusion using lateral cephalogram and cone-beam computed tomography (CBCT). METHODS: Thirty high-angle patients with skeletal class Ⅱ malocclusion who had received preoperative orthodontic treatment and orthognathic surgery in Peking University School and Hospital of Stomatology between Ja-nuary 2017 and August 2022 and had taken lateral cephalogram and CBCT before and after preoperative orthodontic treatment were selected. Items were measured with lateral cephalogram including: The lower central incisor (L1)-Frankfort plane angle (L1-FH), the L1-mandibular plane angle (L1-MP), the L1-nasion-supramental angle (L1-NB) and the vertical distance from the incisal edge of lower central incisor to NB line (L1-NB distance), etc. The incidence of dehiscence/fenestration and the length of dehiscence at labial side (d-La) and lingual side (d-Li) were measured using CBCT. Pearson correlation analysis was used to evaluate the correlation between the changes of d-Li of L1 and age, duration of preoperative orthodontic treatment and the cephalometric measurements before preoperative orthodontic treatment to screen out risk factors affecting the periodontal risk of preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusions. RESULTS: After preoperative orthodontic treatment, L1-FH, L1-MP, L1-NB and L1-NB distances changed by 11.56°±5.62°, -11.13°±5.53°, -11.57°±5.43° and (-4.99±1.89) mm, respectively, and the differences were all statistically significant (P < 0.05). Among the 180 measured mandibular anterior teeth, 45 cases with labial dehiscence/fenestration before preoperative orthodontic treatment (T0) had no longer labial dehiscence/fenestration after preope-rative orthodontic treatment (T1); 142 cases without lingual dehiscence/fenestration at T0 had lingual dehiscence/fenestration at T1. After preoperative orthodontic treatment, the d-La of lower lateral incisors (L2), lower canines (L3) and lower anterior teeth (L1+L2+L3) decreased by (0.95±2.22) mm, (1.20±3.23) mm and (0.68±2.50) mm, respectively, and the differences were statistically significant (P < 0.05); the d-Li of L1, L2, L3 and L1+L2+L3 increased by (4.43±1.94) mm, (4.53±2.35) mm, (3.19±2.80) mm and (4.05±2.46) mm, respectively, and the differences were statistically significant (P < 0.05). The increase of d-Li of L1 was positively correlated with L1-FH (r=0.373, P=0.042). CONCLUSION This study showed that high-angle patients with skeletal class Ⅱ ma-locclusion could achieve ideal decompensation effect of mandibular anterior teeth after preoperative orthodontic treatment with bilateral mandibular first premolars extracted, but the lingual periodontal risk of mandibular anterior teeth was increased. This risk could be correlated to L1-FH before preoperative orthodontic treatment, which should be paid more attention in the design of orthodontic-orthognathic surgical treatment.
Humans ; Malocclusion, Angle Class III ; Malocclusion, Angle Class II/surgery* ; Facial Bones ; Incisor ; Orthognathic Surgical Procedures ; Cone-Beam Computed Tomography ; Mandible

In case of loss of many teeth due to dental caries or periodontal disease, improvement of masticatory function and aesthetics can be obtained through implant treatment. However, if the patient does not have a normal intercondylar relationship, it is difficult to achieve an ideal occlusal relationship with only prosthetic treatment. In particular, oral reconstruction with orthodontic treatment or orthognathic surgery is necessary for patients with mandibular prognathism. However, if the posterior occlusion collapses due to severe caries or periodontal disease, orthognathic surgery may be difficult. The occlusal vertical stop is very important for the stability of the mandibular position during occlusal reconstruction through orthognathic surgery. The patient in this case had posterior occlusion collapsed due to the caries of a large number of posterior teeth, and showed mandibular prognathism and long face. We planned a full arch restoration with orthognathic surgery and extracted the hopeless teeth. To secure the vertical stop required for orthognathic surgery, the implant was placed before surgery. After the orthognathic surgery and the final prosthesis application, the results were satisfactory for the improvement of the aesthetics and the restoration of the masticatory function.
Dental Caries ; Dental Implants ; Esthetics ; Humans ; Malocclusion ; Malocclusion, Angle Class III ; Orthognathic Surgery* ; Periodontal Diseases ; Prognathism* ; Prostheses and Implants ; Tooth*

OBJECTIVETo investigate the compensation of the upper and lower incisors in skeletal Class III patients treated with orthodontic-surgical approach.

METHODSThe samples consisted of 54 skeletal Class III patients treated with orthodontic-surgical approach from November 2011 to January 2015. Lateral cephalograms were taken before treatment. The differences between the samples and the norms from Peking University normal occlusion sample library were assessed using independent-sample t test. Correlation analyses were performed to find associations between skeletal and dental parameters. According to skeletal anteroposterior discrepancy/vertical type (ANB/SN-MP), the samples were allocated into group A (ANB < -4°, SN-MP ≤ 37.7°, n = 11), group B (ANB ≥ -4°, SN-MP ≤ 37.7°, n = 16), group C (ANB < -4°, SN-MP > 37.7°, n = 14), and group D (ANB ≥ -4°, SN-MP > 37.7°, n = 13). After measurement of variables, one-way ANOVA with SNK multiple comparison test were performed.

RESULTSThe maxillary incisors were more proclined and the mandibular incisors more retroclined in skeletal Class III patients compared with norm values (P < 0.01). Both skeletal anteroposterior discrepancy and vertical type were correlated with the position of upper and lower incisors (P < 0.01). According to skeletal anteroposterior discrepancy/vertical type, no significant differences were found in the upper incisors' inclination among the four groups, while patients in group A and group D exhibited significant difference in lower incisor compensation.

CONCLUSIONSDifferent skeletal anteroposterior discrepancy/vertical type resulted in varied incisors' compensation. Therefore, decompensation should be treated differently.

Analysis of Variance ; Beijing ; Cephalometry ; Humans ; Incisor ; pathology ; Malocclusion, Angle Class III ; classification ; pathology ; surgery ; Mandible ; Maxilla ; Orthognathic Surgery

OBJECTIVE: To explore the method of measuring root volume with cone-beam computed tomography (CBCT) three-dimensional reconstruction technology, and to study root length and root volume of upper and lower central incisors in patients with skeletal Class Ⅲ malocclusion treated by surgical orthodontic treatment. METHODS: Twenty patients with skeletal Class Ⅲ malocclusion undergoing surgical orthodontic treatment were selected. CBCT data at three time points, before decompensation treatment (T0), after decompensation treatment (before orthognathic surgery, T1), and the end of post-operative orthodontic treatment (T2) were collected. Three-dimensional reconstruction technology was used to measure the root length and root volume of the upper and lower central incisors (including total root volume, cervical root and apical root), calculate the percentage of reduction volume, and measure the distance of tooth movement after orthodontic treatment. Data were statistically analyzed by SPSS 20.0 software. Least significant difference (LSD) method was used for pair comparison between the groups subject to normal distribution, and non-parametric test was used for comparison between the groups not subject to normal distribution. The differences of root length and root volume of upper and lower incisors were compared, and the characteristics of root absorption were analyzed. RESULTS: Root length and root volume of the upper and lower central incisors were reduced during the surgical orthodontic treatment (P < 0.05) in cases. Both the root volume of cervical root and apical root were significantly reduced (P < 0.05), the reduction of apical root was more significant. The percentage of root volume reduction of the upper central incisor was (30.51±23.23)%, and lower central incisor (23.24±11.96)%. Compared with the upper central incisor, the root volume reduction amount and percentage of the lower central incisor were smaller, and apical root volume reduction of the upper central incisor was greater than that of the lower central incisor, which was statistically significant (P < 0.05). During pre-surgical orthodontic treatment, maxillary central incisor palatal moving was in a controlled tipping manner, and the mandibular central incisor tipped labially. CONCLUSION In patients with skeletal Class Ⅲ malocclusion, root length and total root volume of upper and lower central incisors decreased during surgical orthodontic treatment. Root volume measurement indicated that the cervical root also had root resorption. The difference in root resorption of the upper and lower central incisors might be related to the distance and direction of teeth movement. CBCT three-dimensional reconstruction will compensate for the limitation of root length measurement in evaluating root resorption.
Cone-Beam Computed Tomography/methods* ; Humans ; Incisor/diagnostic imaging* ; Malocclusion, Angle Class III/surgery* ; Maxilla/surgery* ; Root Resorption/etiology*

OBJECTIVETo investigate the effects using mini-plate implant as anchorage for maxillary protraction in skeletal Class III malocclusion with retruded maxilla.

METHODSTotally 8 skeletal Class III patients aged 11 - 14 years were included in this study. There were 4 males and 4 females. The mini-plate implants were placed between the upper lateral incisors and canines on both sides in each patient. The mask was used after 1 month healing following mini-plate implant surgery. Cephalography and panoramic radiographs were taken for each patient before and after protraction. Twenty-one cephalometric measurements were used for assessment. Statistically, paired t-test was used.

RESULTSAfter protraction, SNA, ANB, Wits, NA-PA, Max-Lth, A-NP distances increased and the significant difference was founded (P < 0.01). ANS-Me, Is-FHp, Ms-FHp, A-FHp distances increased significantly, too (P < 0.05). L1-AP, OJ, AB-NP decreased and the significant difference was detected (P < 0.05). The changes of SNB, MP-SN, PP-SN, U1-PP, U1-SN, U1-AP, L1-MP and ANS-Me/N-Me ratio were not significant (P > 0.05).

CONCLUSIONSMini-plate implant was an effective and stable anchorage for promoting forward growth of maxilla following maxillary protraction.

Adolescent ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; surgery ; Maxilla ; surgery ; Orthodontics, Corrective ; Osteogenesis, Distraction ; Prostheses and Implants ; Titanium