RESUMO
OBJECTIVES@#This study aimed to use modified articular disc anchorage in treating old irreducible temporomandibular joint (TMJ) disc displacement with perforation and rupture, as well as to explore its efficacy.@*METHODS@#A total of 31 patients (34 sides) with 47 TMJ disc perforations who underwent surgical treatment in the Affiliated Stomatolo-gical Hospital of Nanchang University from January 2018 to December 2021 were selected. According to the location of disc perforation, it has five types: posterior disc perforation (typeⅠ), anterior disc perforation (typeⅡ), lateral disc perforation (type Ⅲ), composite disc perforation, and destruction disc perforation. The modified methods of disc anchoring were divided into two types according to the location of the perforation. TypesⅠandⅢ disc perforation were trea-ted by posterior anchoring method. For posterior ancho-ring, a screw was implanted into the posterolateral side of the condylar neck, and the disc was fixed on the screw by horizontal mattress suture. TypeⅡdisc perforation and compo-site disc perforation combined typeⅡperforation were treated by anterior and posterior double-anchoring method. For anterior anchoring, anchor screws or holes were placed at the anterior edge of the condylar neck, and horizontal mattress suture was performed at the posterior edge of the anterior perforation with an anchor wire. The articular disc was then fixed on the anchor screws or holes. For the posterior anchoring method, it was the same as the previous one. Paired t test was used to analyze the visual analog scale (VAS), maximum interincisal opening (MIO), and TMJ disorder index (CMI) of the patient before surgery and 1, 3, and 6 months after surgery. Disk-condyle position relationship by magnetic resonance imaging and postoperative quality of life in postoperative were analyzed.@*RESULTS@#The incidence of perforation was 41.2% (14/34) in typeⅠ, 11.8% (4/34) in typeⅡ, 8.8% (3/34) in typeⅢ, 29.4% (10/34) in composite type, and 8.8% (3/34) in destruction type. The VAS, MIO, and CMI at 3, 6 months after operation significantly improved compared with those before operation (P<0.05). The effective reduction rate of disc was 96.77% (30/31). The quality of life at 6 months after surgery was 47.22±2.13, and the rate of excellent evaluation was 96.4% (27/28).@*CONCLUSIONS@#Modified articular disc anchorage achieves a good curative effect for treating temporomandibular joint disc perforation and rupture. Nevertheless, its long-term effect requires further observation.
Assuntos
Humanos , Disco da Articulação Temporomandibular/cirurgia , Qualidade de Vida , Luxações Articulares/cirurgia , Transtornos da Articulação Temporomandibular/cirurgia , Imageamento por Ressonância Magnética/métodos , Articulação Temporomandibular/patologia , Côndilo MandibularRESUMO
0bjective@#To establish a three-dimensional finite element model of mandible and study the transverse displacement of proximal segment after Bilateral Sagittal Split Ramus Osteotomy (BSSRO) with different retrogression amounts during mastication.@*Methods@#DICOM data of a skull model were processed with MIMICS and ANSYS software, reconstructing the 3D model including the teeth and temporomandibular joint in order to simulate BSSRO and evaluate the transverse displacement of proximal segment with different retrogression amounts during mastication.@*Results@#The mean of proximal segment width change were 2.955 mm and 3.490 mm, when retrogression amounts of distal segmentwere 3 mm and 8 mm, respectively.No significant difference between the two groups were found (P=0.131). Meanwhile the displacement color scale of the 3D finite element models showed that the apparent transverse displacement distribution of the proximal segment was measured around the gonial area, decreased from the exterior to the interior.@*Conclusions@#The mandibular angle width was significantly expanded right after BSSRO. The masticatory muscle system and single cortical fixation system played an important role in expanding the width of proximal segment. However there was no correlation between the widening effect and retrogression amounts of distal segment of mandible.
RESUMO
Objective@#To evaluate the surgical prediction accuracy of Proplan CMF software for zygomatic reduction surgery using L-shaped osteotomy.@*Methods@#Pre-and-postoperative 1-year CBCT data of 26 patients with zygomatic arch hypertrophy were imported in Proplan CMF software during 2014 Jan. to 2016 Jun., the 3D models were reconstructed for simulation of L-shaped osteotomy, characteristic landmarks were selected and 3D point measurement system was established. The measurement result were analyzed by one-way ANOVA. Meanwhile, the overlap color grading charts of preoperative and simulated images were also observed.@*Results@#The facial width, bilateral zygomatic process angle and facial width index were [(128.56±2.72) mm, (106.87±2.53)°, (108.56±3.02)°and 1.41±0.03] in postoperative result, [(129.49±2.26) mm, (108.68±2.40)°, (108.85±3.02)°and 1.42±0.03]in simulated result and [(135.45±2.45) mm, (102.50±2.60)°, (103.41±2.56)°and 1.48±0.05] in preoperative result, with significant difference between preoperative and postoperative result, or between preoperative and simulated result (P<0.05), while no significance between postoperative and simulated result (P>0.05). The soft tissue zygomatic process distance was(153.25±2.58) mm in preoperative result, (150.23±2.76)mm in postoperative result , (149.36±3.27)mm in simulated result, with no significance between any of two groups result (P>0.05). The zygomatic process distance and bilateral zygomatic process tragal distance were (126.35±2.56) mm, (68.75±2.15) mm and(68.86±3.21) mm in postoperative result, showing significant differences compared with preoperative result [(120.16±3.18) mm, (74.58±3.19) mm and(76.14±3.15) mm] and simulated result [(118.86±3.45) mm, (73.85±3.57) mm and(76.87±2.58) mm] respectively(P<0.05), while zygomatic arch distance was not statistically different among the three groups(P>0.05). It indicated that predictive accuracy of facial width, facial width index, zygomatic process angle, soft tissue zygomatic arch distance was high but the soft tissue zygomatic process distance and zygomatic process tragal distance was relatively low. Meanwhile, the color overlay image showed that predictive accuracy was not good in the zygomatic region while the zygomatic arch area was high.@*Conclusions@#The predictive accuracy of Proplan CMF software for zygomatic arch hypertrophy is relatively high except for the zygomatic region. Further improvement of the CMF software is needed.
RESUMO
BACKGROUND:Bilateral-sagitta-split-ramus-osteotomy (BSSRO) has become a conventional method to correct facial deformities, and the finite element method is a significant way to study biomechanics of the mandible and temporomandibular joint (TMJ) after BSSRO. OBJECTIVE: To establish a precise and high simulation model of mandible containing TMJ after BSSRO with internal fixation, which is the base to study the biomechanics of the mandible and TMJ after BSSRO. METHODS: Spiral CT scan was used to get the data of DICOM that were input into MIMICS to establish the three-dimensional model of the mandible. The three-dimensional model was wrapped into a single closed shel for mesh generation and conversion in ANSYS. Then, the model was input into the ANSYS software for temporomandibular joint reconstruction and simulation of BSSRO and internal fixation. RESULTS AND CONCLUSION: The three-dimensional finite element model of mandible containing TMJ after BSSRO was established using MIMICS and ANSYS. This model had biological similarity and geometric similarity in comparison with the human tissues. The model could undergo various internal fixations through antedisplacement, retroposition and rotational movement of the distal end. Based on different experimental purposes, the established model can apply a load to al parts to study changes in stress and displacement of different tissues after BSSRO and internal fixation, and it also can be used to study the effect of different fixation materials on the rear stability after internal fixation.