OBJECTIVES: This study aims to compare the effects of two orthodontic treatment modalities for skeletal class Ⅲ malocclusion on specific changes in airway volume, morphology, palatal angle, mandibular rotation, and bone displacement. Results provide scientific evidence for the selection of orthodontic treatment plans and reduce the risk of developing obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Thirty-six patients diagnosed with skeletal class Ⅲ malocclusion at the Department of Orthodontics, the Affiliated Stomatological Hospital of Nanjing Medical University from September 2018 to December 2023 were divided into two groups: orthodontic-orthognathic treatment group (18 patients) and camouflage orthodontic treatment group (18 patients). Changes in airway volume, cross-sectional area, palatal angle, mandibular, and tongue positions were observed through pre- and post-operative cone beam computed tomography and 3D cephalometric measurements. RESULTS: In the camouflage orthodontic treatment group, nasopharyngeal volume and oropharyngeal volume statistically increased after treatment (P<0.05). In the orthodontic-orthognathic treatment group, changes in nasopharyngeal volume, nasopharyngeal airway, distance from posterior tongue to pharyngeal wall, palatal angle, mandibular rotation, and hyoid bone displacement were statistically significant after surgery (P<0.05). In the comparison between the two groups after treatment, changes in the distance from posterior tongue to pharyngeal wall, palatal angle, and distance from hyoid bone to sella turcica point were statistically significant (P<0.05). CONCLUSIONS Patients in the orthodontic-orthognathic treatment group showed significantly greater changes in oropharyngeal cross-sectional area, palate angle, and tongue position compared with patients in the camouflage orthodontic treatment group. As individuals susceptible to OSAHS often exhibit mandibular retrusion and decreased minimum airway cross-sectional area, special attention should be paid to airway morphology changes when adopting orthodontic-orthognathic treatment to avoid adverse consequences.
Humans ; Hyoid Bone/diagnostic imaging* ; Malocclusion, Angle Class III/therapy* ; Male ; Female ; Cone-Beam Computed Tomography ; Cephalometry ; Orthodontics, Corrective/methods* ; Adult ; Mandible ; Pharynx/diagnostic imaging* ; Sleep Apnea, Obstructive/etiology* ; Orthognathic Surgical Procedures

OBJECTIVE: To assess three-dimensional (3D) changes of circummaxillary sutures following maxillary protraction with alternate rapid palatal expansions and constrictions (RPE/C) facemask protocol in maxillary retrusive children, and to investigate the relationship between the changes of circum-maxillary sutures and zygomaticomaxillary suture (ZMS) maturation, and to explore the factors of maxilla forward movement with RPE/C and facemask. METHODS: In the study (clinical trial registration No: ChiCTR2000034909), 36 maxillary retrusive patients were recruited and block randomized to either the rapid palatal expansion (RPE) group or the RPE/C group. Patients aged 7 to 13 years, Class Ⅲ malocclusion, anterior crossbite, ANB less than 0°, Wits appraisal less than -2 mm, and A-Np less than 0 mm were included in the study. The RPE group received rapid palatal expansion, whereas the RPE/C group received alternate rapid palatal expansions and constrictions, and both with facemask protraction. Head orientations of cone-beam computed tomography (CBCT) images were implemented by Dolphin 11.7. 3D measurements of circummaxillary sutures on CBCT images were evaluated using Mimics 10.01 before (T0) and after treatment (T1). The changes were analyzed with independent t test, two-way ANOVA, Pearson correlation and regression analysis. RESULTS: Two subjects in the RPE/C group were lost to follow-up. A total of 34 patients reached the completion criteria and were analyzed. Compared with the RPE group, sagittal changes of circummaxillary sutures were significantly increased in the RPE/C group with 1.21 mm advancement of zygomaticotemporal suture, 2.20 mm of ZMS, 1.43 mm of zygoma-ticofrontal suture (P < 0.05, respectively). Except for the zygomaticotemporal suture, the rest forward sagittal changes of other circummaxillary sutures showed no major difference in terms of the ZMS maturation. The Spearman's correlation in RPE/C indicated a strong positive correlation of sagittal changes between ZMS and point A (P < 0.01) with a regression analysis R²=42.5%. CONCLUSION RPE/C might be more effective on the treatment of maxillary retrusive children. As one of the major mechanical loading sutures during orthopedic therapy, ZMS showed a strong positive correlation with point A on sagittal changes.
Cone-Beam Computed Tomography/methods* ; Constriction ; Humans ; Malocclusion, Angle Class III/therapy* ; Maxilla/diagnostic imaging* ; Palatal Expansion Technique ; Sutures

OBJECTIVE: To use the cone-beam computed tomography (CBCT) to evaluate the three-dimensional (3D) changes of maxillary landmarks in the maxillary protraction with alternating rapid palatal expansion and constriction and with rapid palatal expansion, and to provide some clinical suggestions for the early treatment of Class III malocclusion. METHODS: A total of 36 maxillary retrusive patients were included and randomized in a 1:1 ratio to either the intervention group (alternating rapid palatal expansion and constriction group, RPE/C) or the control group (rapid palatal expansion group, RPE). Randomization was accomplished with permuted block randomization based on participation sequence. The patients in the RPE/C were treated for 10 weeks (0.5 mm/d) with the repetition of two-week palatal expansion and two-week palatal constriction. The patients in the RPE were taught to complete rapid palatal expansion for 2 weeks (0.5 mm/d ). The patients were instructed to come to the office for the follow-up to ensure the correct procedures. Damaged expanders were repaired (or replaced) and rebanded quickly. Sequential CBCT images including pretreatment (T1), post-expansion (T2) and post-protraction (T3) were required for 3D reconstruction, establishment of landmarks, measurement and analysis by Mimics 10.01. RESULTS: There was significant forward movement of subspinale (A) in the RPE/C after the treatment with (3.06±1.29) mm, compared with RPE (2.16±1.27) mm, P<0.05. There were more symmetrical changes of the landmarks in the RPE/C and there was no statistic significance of the entire treatment time between the two groups. Moreover, the maxillary skeletal landmarks had the following 3D changes of a forward and downward movement during the expansion stages T2-T1, a forward and upward movement during the protraction stages T3-T2 and a forward and downward movement during the total treatments T3-T1 compared with the control group. And the width between the bilateral landmarks increased during the expansion stages T2-T1, narrowed down during the protraction stages T3-T2 and increased during the total treatments T3-T1. CONCLUSION The maxillary protraction with alternating rapid palatal expansion and constriction provided clinical benefits on maxillary advancement and symmetrical changes in the orthopedic treatment of the patients with maxillary retrognathism and it required further study on the orthodontic analysis and measurements of CBCT.
Cephalometry ; Cone-Beam Computed Tomography ; Constriction ; Humans ; Malocclusion, Angle Class III/therapy* ; Maxilla ; Palatal Expansion Technique

OBJECTIVETo investigate the outcome of skeletal Class Ⅲ patients treated with Fränkel function regulator type Ⅲ (FR Ⅲ)in the early mixed and late mixed dentition.

METHODSThe samples consisted of 45 mild and moderate skeletal Class Ⅲ patients(26 males, 19 females; meanage, [7.9±1.3] years) treated with FR Ⅲ. According to Hellman's dental developmental stages, these samples were divided into early-treated group(n=24) and late-treated group(n=21). Lateral cephalograms were taken at the beginning and the end of treatment. Twenty-one measurements on hard and soft tissue were included.

RESULTSAfter treatment, SNA, ANB, NA-Apo, Wits, U1-SN, U1-NA, Overjet, UL-EP were significantly increased (1.0±1.9)°, (1.2±1.6)°, (2.6±4.2)°, (1.8±2.7) mm, (4.2±7.6)°, (2.6±7.5)°, (3.6±2.3) mm and (0.8±2.2) mm(P<0.05). OP-SN and IMPA were significantly decreased (1.5±3.7)°and (1.4±4.2)°(P<0.05). There were significant differences in SNA, ANB, UL-EP, IMPA, L1-NB between early-treated group and late-treated group(P<0.05).

CONCLUSIONSFR Ⅲ was suitable for the treatment of mild and moderate skeletal Class Ⅲ patients. The result was better in the early-treated patients than in late-treated ones.

Cephalometry ; Child ; Dentition, Mixed ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; therapy ; Orthodontic Appliances, Functional ; Overbite ; etiology ; Time-to-Treatment ; Treatment Outcome

Adult ; Humans ; Malocclusion, Angle Class III ; therapy ; Orthodontics ; Orthodontics, Corrective ; methods ; Preoperative Care ; methods

This study aimed to assess the reliability of experienced Chinese orthodontists in evaluating treatment outcome and to determine the correlations between three diagnostic information sources. Sixty-nine experienced Chinese orthodontic specialists each evaluated the outcome of orthodontic treatment of 108 Chinese patients. Three different information sources: study casts (SC), lateral cephalometric X-ray images (LX) and facial photographs (PH) were generated at the end of treatment for 108 patients selected randomly from six orthodontic treatment centers throughout China. Six different assessments of treatment outcome were made by each orthodontist using data from the three information sources separately and in combination. Each assessment included both ranking and grading for each patient. The rankings of each of the 69 judges for the 108 patients were correlated with the rankings of each of the other judges yielding 13 873 Spearman rs values, ranging from -0.08 to +0.85. Of these, 90% were greater than 0.4, showing moderate-to-high consistency among the 69 orthodontists. In the combined evaluations, study casts were the most significant predictive component (R(2)=0.86, P<0.000 1), while the inclusion of lateral cephalometric films and facial photographs also contributed to a more comprehensive assessment (R(2)=0.96, P<0.000 1). Grading scores for SC+LX and SC+PH were highly significantly correlated with those for SC+LX+PH (r(SC+LX)vs.(SC+LX+PH)=0.96, r(SC+PH)vs.(SC+LX+PH)=0.97), showing that either SC+LX or SC+PH is an excellent substitute for all three combined assessment.
Adolescent ; Cephalometry ; standards ; China ; Dental Models ; standards ; Esthetics, Dental ; Female ; Humans ; Male ; Malocclusion, Angle Class I ; therapy ; Malocclusion, Angle Class II ; therapy ; Malocclusion, Angle Class III ; therapy ; Orthodontics ; standards ; Peer Review, Health Care ; standards ; Photography ; standards ; Reproducibility of Results ; Treatment Outcome

OBJECTIVETo analyze the three-dimensional changes of pharyngeal airway in patients with skeletal Class III malocclusion after the combined orthodontic and orthognathic treatment.

METHODSTwenty patients (9 males, 11 females) and 40 subjects with normal occlusion were involved in the study. Cone-beam computed tomography (CBCT) were performed on patients one week and six months after treatment. Raw data were reconstructed into three-dimensional model and sagittal and transversal measurements, cross sectional areas, partial and total volumes were computed.

RESULTSAfter treatment, the sagittal diameters of each section were significantly reduced by (2.7 ± 3.5), (3.0 ± 3.8), (2.7 ± 3.3) mm, respectively (P < 0.05). The transversal diameter of laryngopharyngeal airway constricted significantly by (4.8 ± 4.1) mm (P < 0.05). Cross sectional areas and volumes of each part in patients after surgery were significantly narrower compared with those of the controls.

CONCLUSIONSAfter combined therapy the pharyngeal airway space decreased.

Adolescent ; Adult ; Cone-Beam Computed Tomography ; Female ; Humans ; Hypopharynx ; diagnostic imaging ; Imaging, Three-Dimensional ; Male ; Malocclusion, Angle Class III ; diagnostic imaging ; surgery ; therapy ; Orthodontics, Corrective ; Osteotomy, Sagittal Split Ramus ; Pharynx ; diagnostic imaging ; Young Adult

Fingersucking ; adverse effects ; Humans ; Malocclusion ; etiology ; therapy ; Malocclusion, Angle Class II ; therapy ; Malocclusion, Angle Class III ; therapy ; Orthodontic Brackets ; Orthodontics, Corrective ; methods ; Orthodontics, Interceptive ; methods ; Palatal Expansion Technique ; Time Factors ; Tongue Habits ; adverse effects ; Tooth Extraction ; Tooth, Impacted ; surgery

OBJECTIVETo investigate the effects of orthodontic treatment on temporomandibular joint (TMJ) in adult low-angle patients with skeletal class III malocclusion.

METHODSSixteen adult female low-angle patients with skeletal class III malocclusion were included in the study. All patients were treated with OPA-K straight wire technique. Lateral cephalometric and corrected transcranial projection films were taken before and after treatment. Cephalometric analysis was carried out. All data were analyzed statistically.

RESULTSAfter orthodontic treatment, the linear measurement and area of anterior space in TMJ increased by 0.27 mm (P < 0.001) and 0.70 mm(2) (P < 0.01), respectively, while the posterior space decreased by 0.24 mm and 0.67 mm(2), respectively (P < 0.001). Linear ratio decreased from 22.13% to 9.64% (P < 0.001), and area proportion decreased from 1.56 to 1.19 (P < 0.01). Anterior space became equal to the posterior space. Cephalometric analysis showed that point Co, Ar, Go and Pg were all retruded (P < 0.05).

CONCLUSIONSAfter orthodontic therapy, the condyle moved posteriorly to normal concentric position, which would be helpful in alleviating temporomandibular disorders (TMD) symptom in adult low-angle patients with skeletal class III malocclusion.

Adolescent ; Female ; Humans ; Malocclusion, Angle Class III ; pathology ; therapy ; Matched-Pair Analysis ; Orthodontics, Corrective ; Retrospective Studies ; Temporomandibular Joint ; pathology ; Young Adult

Child ; Dental Implantation, Endosseous ; Extraoral Traction Appliances ; Humans ; Male ; Malocclusion, Angle Class III ; therapy ; Maxilla ; abnormalities ; Orthodontic Anchorage Procedures ; instrumentation ; Orthodontic Appliance Design ; Orthodontics, Corrective ; instrumentation