ABSTRACT
Objective@#To investigage the three-dimensional changes in condylar position after bilateral sagittal split ramus osteotomy (BSSRO) in skeletal class Ⅲpatients with mandibular deviation using cone-beam CT (CBCT).@*Methods@#Twenty-five skeletal class Ⅲ patients with mandibular deviation were included. The patients (12 males and 13 females, aged 19-25 years, average age 22.4 years) were treated in the Department of Orthodontics, Affiliated Stomatological Hospital, Nanchang University from October 2013 to March 2017. The patients were divided into T1, T2 and T3 groups (T1 group: CBCT taken within 1 week before operation; T2 group: CBCT taken within 1 week after operation; T3 group: CBCT taken 6-8 months after surgery). Three sets of image data of condyles on both sides (deviation side and contralateral side) were obtained. After the DICOM data collection, the software of Mimics 17.0 was used to perform three-dimensional reconstruction and condylar position measurements: the distance from the condylar top (CoT) to the standard horizontal plane (SHP), the middle sagittal plane (MSP) and the sella coronal plane (SCP) (CoT-SHP, CoT-MSP, CoT-SCP); the distance from the condylar center (CoC) to SHP, MSP and SCP (CoC-SHP, CoC-MSP, CoC-SCP); the angle from the condyle cella plane (CCP) to SHP, MSP and SCP (CCP-SHP, CCP-MSP, CCP-SCP); the angle from the condyle sagittal plane (CSP) to SHP, MSP and SCP (CSP-SHP, CSP-MSP, CSP-SCP) and the distance of the anterior, superior, posterior, medial, central and lateral joint space. One-way ANOVA and LSD-t test were used to compare the changes in condylar position at different periods (T1, T2, and T3).@*Results@#Within 1 week before operation on the deviation side, CoT-SHP [(2.5±1.3) mm], CSP-MSP (41.2°±8.4°) and the posterior joint space [(2.0±0.6) mm] were obviously increased (P<0.05), and CoT-SCP [(9.1±3.3) mm], CCP-MSP (78.2°±5.2°) were decreased significantly (P<0.05); on the contralateral side, CoT-MSP [(50.4±3.1) mm], CCP-MSP (80.6°±6.0°), the anterior joint space [(2.2±0.6) mm] and the medial joint space [(2.6±0.6) mm] were obviously increased (P<0.05), and CCP-SCP (11.4°±8.8°) were decreased significantly (P<0.05). Six to eight months after surgery, CoT-SHP [(2.2±1.0) mm] and the posterior joint space [(1.9±0.5) mm] on deviation side and CoT-SCP [(8.4±2.8) mm] on the contralateral side were increased significantly (P<0.05). No significant difference was found in other measurements (P>0.05).@*Conclusions@#The condylar position in skeletal class Ⅲ patients with mandibular deviation was asymmetrical. Within 1 week after the operation of BSSRO, the condyle on the deviation side was moved forward, downward and inward. Meanwhile, the condyle on the contralateral side was moved backward and outward. Six to eight months after surgery, the condylar position on both sides was gradually restored to the pre-operative condylar position.
ABSTRACT
Objective:To evaluate the influence of Tweed-Merrifield technique in correction of severe bimaxillary protrusion adult patients on the measurement of the dental and skeletal changes after orthodon-tic treatment by Johnston analysis and the regular cephalomatric analysis.Methods:Twelve adolescent patients with severe bimaxillary protrusion were included in this self-control retrospective study.Lateral cephalometric radiographs were taken before and after treatments.All the radiographs were traced and analyzed by the method of Johnston analysis.Other measurements were evaluated using a series of 1 3 li-near and angular measurements including SNA,SNB,ANB,U1 -SN,U1 -NA,U1 /NA,L1 -NB, U1 /NB,L1 /MP,U1 -L1 ,(U1 +L1 )/2-AB,MP/SN and MP/FH from regular cephalomatric analysis. These measurements were also applied to compare the differences between pre-and post-treatments,which clarify the dental and skeletal changes by Johnston analysis.The effect of orthodontic correction was de-termined using the non-parameters test.Results:The maxillary moved backforward by 1 .3 mm according to the stable skull base,while the mandible moved forward by 2.1 2 mm.The relative position between the maxillary and mandible (ABCH)changed 3.42 mm.The upper and lower incisors retracted signifi-cantly.The upper and lower molars moved slightly forward and the relative positions of upper and lower molars and anterior teeth after treatment were 3.44 mm and 4.23 mm respectively.After treatment,the parameters of ANB、U1 -NA、U1 /NA、U1 -SN、L1 -NB、L1 /NB and L1 -M were reduced by -(1 .98 ± 1 .55)°(P =0.01 2),-(5.08 ±4.6)mm (P =0.002),-(1 1 .79 ±1 .21 )°(P =0.004),-(1 3.55 ±6.32)°(P =0.047), -(3.1 7 ±3.07)mm (P =0.01 0), -(6.84 ±2.55)°(P =0.038)and-(4.1 3 ±2.24)°(P =0.048)on average,whose changes had the statistically significant effects.Con-clusion:Tweed-Merrifield technique (directional force technique)can stabilize anchorage molar,retract anterior teeth and significantly improve the hard and soft tissue profile for patients with bimaxillary protru-sion,and make a good vertical control which means this technique is applicable to the patients who need strong anchorage.Even for the severe bimaxillary protrusion adult patients,the Tweed-Merrifield tech-nique can control the anchoragewell and make the profiles improved greatly.
ABSTRACT
Gliomas harbor a small population of cells termed glioma stem-like cells (GSC),which have the ability to undergo self-renewal and initiate tumorigenesis.GSCs are resistant to a wide variety of chemotherapeutic agents and possess a remarkable ability to recover from cytotoxic therapy.Furthermore,GSCs play a crucial role in RT failure,as tumors surviving RT are enriched in GSCs.Therefore,an alternative strategy involving selective targeting of this functionally distinct chemo-and radiation resistant small group of GSCs rather than the bulk of the tumor may be more successful in treating this deadly disease.GSC exhibit various alterations to signaling pathway activity,which are associated with self-renewal and neoplastic proliferation.These altered pathways may represent possible targets for GSC.