发育期羊全颞下颌关节置换术后的下颌骨对称性评价

目的:利用Surgicase5.0软件对发育期羊全颞下颌关节(temporomandibular joint,TMJ)置换进行手术设计,研究其重建后的下颌骨对称性。方法:选择6个月龄山羊6只,术前行CT检查,收集数据(Dicom格式),通过Surgicase5.0软件重建三维数字模型,结合快速成型技术获得羊三维头颅树脂模型,在模型上设计、制备个性化人工全TMJ假体,并模拟手术,进行全TMJ置换;右侧进行手术,作为实验组,左侧为对照组。术后1、4、12周行CT扫描,在三维模型上测量两侧下颌支高度(ramus heights,RH)、下颌体长度(mandibular body length,ML)、髁突顶点到下颌中切牙近中接触点距离(condyle-incisor,CI)、下牙槽座角到髁突顶点距离(subramental-condyle,BC),采用SPSS16.0软件包对所测数据进行左右侧配对t检验,左右侧各时间点分别与术前进行配对t检验。结果:所有动物均存活至实验完成,能正常进食。术后1、4周左右侧RH、ML、CI、BC均无显著差异(P>0.05);术后12周,除ML外,左右侧RH、CI、BC差异有显著性(P<0.05)。右侧术后1周RH、ML、CI、BC,4周RH、BC,12周RH与术前比较均无显著差异(P>0.05)。左侧术后1周RH、ML、CI、BC,4周RH与术前比较无显著差异(P>0.05)。结论:个性化设计的羊全TMJ假体能较好地行使关节功能。对发育期羊进行全TMJ假体置换,术后远期可能致面形不对称。     

Stability study of total temporomandibular joint replacement on sheep

ObjectiveTo evaluate the stability of our custom-made prosthesis by establishing the model of sheep total temporomandibular joint (TMJ) replacement.MethodsSix sheep were included in our study. Spiral computed tomography (CT) data of all sheep was obtained and transformed into 3-dimensional model by surgicase5.0 software preoperatively. Total TMJ prostheses were made based on the skull model. Ultra-high molecular weight polyethylene was used to make glenoid fossa lining, while titanium alloy to prefabricate mandibular retention handle and titanium plate over glenoid fossa. Cobalt-chromium-molybdenum alloy was also used to prefabricate the condyle. The right sides of all sheep, as the experimental group, were carried out total TMJ replacement, while the left sides were as the control group. The bone in both experimental and control side were excised after 3 and 6 months. Scanning electron microscope (SEM) was used to observe the interface between bone and prosthesis. Van Gieson staining and immunohistochemical staining (IHC) were used respectively to observe the interface of titanium screw and bone and the expression of alkaline phosphatase (ALP).ResultsSEM and Van Gieson staining showed that there was immature bone and osteoid formed in the interface of prosthesis and bone after 3 months. While after 6 months, there was osseointegration between them. IHC showed that the expression of ALP in the experimental side was much higher than in the control side after 3 months and its expression decreased after 6 months with no difference from the control side.ConclusionThe custom-made TMJ prosthesis which was designed and manufactured by ourselves has good stability after total TMJ replacement.     

全颞下颌关节假体植入山羊后的安全性评价

目的:通过建立山羊全颞下颌关节置换模型,探讨植入后山羊的血液学和组织学变化,评价自行设计的人工全颞下颌关节假体的安全性。方法:取健康6个月龄山羊10只,随机选取6只山羊,根据其颞下颌关节螺旋CT所测参数,采用Surgicase5.0软件重建三维头颅模型,制备人工全颞下颌关节假体,选用超高分子量聚乙烯制备关节窝衬里,钛合金制作下颌固位柄及关节窝上方钛板,钴-铬-钼合金制备髁突。另4只作为正常对照组。手术切除实验组6只山羊右侧髁突及关节盘,进行全关节置换。术前1周及术后1周、1、3、6个月采血,测定肝、肾功指标。术后3、6个月取山羊的肝、肾组织和假体周围及对侧下颌骨组织,通过TUNEL染色检测凋亡细胞并进行组织病理染色。采用SPSS16.0软件包对数据进行成组t检验。结果:所有实验动物均存活至实验完成,能够正常进食。各时间点实验组与对照组肝、肾功指标差异无显著性,肝、肾组织病理染色以及凋亡率与正常对照组一致,实验侧与对照侧骨组织均无明显炎症反应,实验侧组织在术后3个月成骨细胞较对照侧增多,术后6个月与对照侧组织无显著差异。结论:自行研制的全颞下颌关节假体具有较好的生物相容性和生物安全性。     

可吸收螺钉微创治疗髁突矢状骨折的实验研究

目的：通过动物实验，为临床髁突矢状骨折（SFMC）探索一种微创的手术治疗方法。方法：6只成年绵羊双侧髁突制备成SFMC模型，右侧采用牵引螺钉辅助复位，可吸收螺钉内固定手术治疗，左侧为对照组，采用保守治疗，12周后通过影像学检查和解剖学观察、测量，比较2组颞下颌关节（TMJ）的形态变化，并进行统计学分析。结果：实验组TMJ形态基本正常，TMJ形态改变的放射学评分显著低于对照组，对照组TMJ形态明显异常。结论：动物实验显示，牵引螺钉辅助复位，可吸收螺钉内固定治疗，是一种微创的SFMc手术治疗方法，应用于临床尚需进一步深入研究。     

颞下颌关节强直动物模型中最大张口度与强直严重程度关系研究

 目的　研究主、被动最大张口度（AMMO、PMMO）与颞下颌关节强直严重程度的关系。方法　选取28只健康雄性绵羊随机分为实验组和对照组,每组各14只。实验组绵羊双侧颞下颌关节模拟髁突矢状骨折,其中左侧翼外肌被切断以阻断其功能;对照组绵羊未进行手术。于术前及术后12、24周对所有绵羊体重、AMMO、PMMO、颞下颌关节形态学特点进行测量评估。结果　实验组只有右侧保留翼外肌功能的颞下颌关节发生了骨强直。术后12、24周,实验组绵羊AMMO、PMMO、极限距离均显著低于对照组,差异均有统计学意义（均P < 0.05）。实验组绵羊AMMO和PMMO与骨融合区宽度、长度、面积及钙化程度均呈负相关（均P < 0.05）,其中骨融合区面积为主要影响因素（术后12、24周相关系数r分别为-0.94、-0.95）。结论　颞下颌关节强直动物模型中阻断翼外肌功能可阻止骨强直的发生;对于早期髁突矢状骨折,可通过牙合垫或牙合板进行张口训练,进而阻断翼外肌功能。当颞下颌关节发生骨强直时,骨融合区面积越大,张口受限越明显。     

颞下颌关节强直动物模型中最大张口度与强直严重程度关系研究

目的　研究主、被动最大张口度（AMMO、PMMO）与颞下颌关节强直严重程度的关系。方法　选取28只健康雄性绵羊随机分为实验组和对照组，每组各14只。实验组绵羊双侧颞下颌关节模拟髁突矢状骨折，其中左侧翼外肌被切断以阻断其功能；对照组绵羊未进行手术。于术前及术后12、24周对所有绵羊体重、AMMO、PMMO、颞下颌关节形态学特点进行测量评估。结果　实验组只有右侧保留翼外肌功能的颞下颌关节发生了骨强直。术后12、24周，实验组绵羊AMMO、PMMO、极限距离均显著低于对照组，差异均有统计学意义（均P < 0.05）。实验组绵羊AMMO和PMMO与骨融合区宽度、长度、面积及钙化程度均呈负相关（均P < 0.05），其中骨融合区面积为主要影响因素（术后12、24周相关系数r分别为-0.94、-0.95）。结论　颞下颌关节强直动物模型中阻断翼外肌功能可阻止骨强直的发生；对于早期髁突矢状骨折，可通过牙合垫或牙合板进行张口训练，进而阻断翼外肌功能。当颞下颌关节发生骨强直时，骨融合区面积越大，张口受限越明显。     

The effect of polishing techniques and time on the surface characteristics and sealing ability of resin composite restorations after one-year storage

Since there is a lack of information on the surface properties of composite restorations achieved with standard polishing procedures after aging processes, this study evaluated the effects of immediate (IM) and delayed (DE) polishing on the surface roughness (Ra), microhardness (KHN) and microleakage (ML) of microfilled (Filtek A110) and hybrid (Filtek Z250) resin composites after one-year storage. Standardized preparations were made on the buccal surface of 256 bovine teeth, where half were restored with each composite. For each composite, the specimens were randomly allocated to two subgroups. The first group (IM) was polished immediately after gross finishing using three different systems/techniques (n=16): Sof-Lex, Flexicups and Flexicups + Jiffy Polishing Brush + Flexibuffs (sequential), then stored for three weeks in saline. The DE group was stored for two weeks, polished with the same systems and stored for one week. From each subgroup, eight specimens were assessed after three weeks regarding Ra, KHN and ML (baseline), andthe eight remaining specimens were stored for one year before analysis. The data were analyzed (alpha=0.05) with ANOVA, paired Student's t-test (Ra and KHN) or Kruskal-Wallis and Signed Rank tests (microleakage). After one year, microfilled resin composite specimens showed the lowest Ra and KHN (p<0.05). N o differencein microleakage was observed among the different groups (p>0.05). The sequential technique provided the lowest roughness and Sof-Lex the lowest hardness (p<0.05). IM showed similar or better performance than DE for ML and Ra (p<0.05). In conclusion, aging increased the composites Ra and ML in all experimental conditions (p<0.05).     

Comparison of the antimicrobial efficacy of 1.3% NaOCl/BioPure MTAD to 5.25% NaOCl/15% EDTA for root canal irrigation

The purpose of this study was to compare the antimicrobial efficacy of 1.3% NaOCl/BioPure MTAD to 5.25% NaOCl/15% EDTA for root canal irrigation. Twenty-six bilaterally matched pairs of human teeth were collected. The teeth were incubated with Enterococcus faecalis for 4 weeks. The teeth were divided into two experimental groups and one positive control group. The canals were instrumented and irrigated with either 5.25% NaOCl/15% EDTA or 1.3% NaOCl/BioPure MTAD. Bacterial samples were collected after instrumentation/irrigation and after additional canal enlargement. Statistical analysis of the data using the Wilcoxon Signed Rank test showed significant differences between the experimental groups. The first bacterial samples revealed growth in 0 of 20 samples with 5.25% NaOCl/15% EDTA irrigation and in 8 of 20 samples with 1.3% NaOCl/BioPure MTAD irrigation. Samples taken after additional canal enlargement revealed growth in 0 of 20 samples in 5.25% NaOCl/15% EDTA and in 10 of 20 samples in 1.3% NaOCl/BioPure MTAD group. This investigation showed consistent disinfection of infected root canals with 5.25% NaOCl/15% EDTA. The combination of 1.3% NaOCl/BioPure MTAD left nearly 50% of the canals contaminated with E. faecalis.     

Synovial matrix metalloproteinase-2 in different stages of sheep temporomandibular joint osteoarthrosis.

PURPOSE: The purpose of this study was to test for the presence of matrix metalloproteinase (MMP) in synovial fluid of sheep with experimentally induced temporomandibular joint (TMJ) osteoarthrosis (OA) at various time intervals. MATERIALS AND METHODS: Twenty-one sheep were used in this study. TMJ OA was induced bilaterally in 18 sheep and 3 sheep were used as controls. Each experimental group had 3 sheep, and the groups were killed at 2, 4, 6, 8, 12, and 24 weeks postoperatively. Synovial fluid was collected at killing, and the joints were evaluated histologically. Gelatin zymography was performed to detect the presence of MMPs in the synovial fluid. RESULTS: TMJ OA gradually progressed over time. ProMMP-2 was detected in all experimental groups. However, the activated form of MMP-2 was only detected at 2 and 4 weeks postoperatively. CONCLUSION: Activated MMP-2 activity correlates with initial articular cartilage destruction rather than with the progression of OA in the sheep TMJ.     

Pathological changes in the TMJ and the length of the ramus in patients with confirmed juvenile idiopathic arthritis

IntroductionJuvenile idiopathic arthritis (JIA) is characterized by a progressive destruction of the joints. The temporomandibular joints (TMJ) are especially likely to be affected. The often undetected arthritis in the TMJ in particular can cause significant destruction and craniofacial developmental abnormalities. The aim of this study was to analyze the destructive impact of JIA on TMJ and mandibular development.Material and methodsWe analyzed a total of 92 joints and mandibular rami using digital cone-beam tomography (CBT) and compared 23 consecutively treated JIA patients with 23 healthy controls, matched for age and gender. We evaluated ramus length, vertical depth of the articular fossa, anterior–posterior dimensions of the mandibular head and condylar process. The statistical analysis was performed using non-parametric Wilcoxon and Kruskal–Wallis Rank Sum tests.ResultsThe JIA patients exhibited significantly more pronounced asymmetries. However, we were unable to detect significant differences in the metric measuring distances. The different JIA subtypes exerted no statistically significant influence.ConclusionsThe possible destruction arising as a result of JIA concerns the TMJ and the length of the mandibular ramus. These craniofacial anomalies demonstrate the central importance of sufficiently early detection and timely treatment in the prevention of such growth disturbances.     

Comparison between the counter-rotational toothbrush and multi-action toothbrush

Previous studies have demonstrated that two types of powered toothbrushes (Interplak and Braun) are more effective than a manual toothbrush in the removal of bacterial plaque from tooth surfaces. The purpose of this study was to compare the effectiveness of the Interplak Home Plaque Removal Instrument (A) and the Braun Electric Toothbrush (B) on supragingival plaque removal and gingival bleeding following (1) one time instruction; (2) reinstruction and one week of home use; (3) a third instruction and three weeks of home use. The sample population for this study consisted of twelve subjects: six (6) were randomly assigned to use the Interplak, and the remaining six (6) were assigned to use the Braun. Subjects met specific qualification criteria to participate in this examiner-blind study. The Turesky Modification of the Quigley-Hein Plaque Index and an Objective-Subjective Gingival Abrasion Index were scored before and after brushing at the initial appointment, one week later, and at the final appointment in three weeks. A timed bleeding index (Barnett-Muhleman) and probing depths were recorded at the beginning of all three appointments. Subjects received instructions on the use of the assigned toothbrush in a clinical demonstration and in a printed format to take home. Subjects were then supervised in their brushing technique. Data was analyzed using a Wilcoxon Signed Rank Test and Analysis of Variance with Repeated Measures where appropriate. Although the number of patients was small, a statistically significant difference (p less than .05) in plaque scores between the groups was obtained in favor of the Interplak.(ABSTRACT TRUNCATED AT 250 WORDS)     

Experimental forward mandibular displacement in sheep.

In order to investigate growth modifications of the temporomandibular joint (TMJ) during dentofacial orthopaedic treatment, specific functional appliances have been used experimentally to prompt the mandible into a protrusive position in various animal models. The purpose of this study was to test the effectiveness of a functional appliance specially designed for sheep and to evaluate the sheep as a model for dentofacial orthopaedic research. Eight, 4-month-old, castrated male Merino sheep were randomly assigned to experimental or control groups, with four in each group. Cast functional appliances were fabricated for the animals in the experimental group. The treatment period was 15 weeks. Dental casts, endosseous implant markers and cephalograms were used to analyse the displacement of the mandible. Undemineralised sagittal sections of TMJ were used to evaluate the tissue responses induced by the appliances. The weight of the animals was measured monthly to monitor their growth. The growth of the metacarpus was also measured. During the experimental period, the animals maintained their weight within the normal range and grew normally. The appliance displaced the mandible to a downward and forward position. The adaptive responses in the TMJ induced by the appliances included changed anteroposterior shape of the condylar process, anteriorly thickened condylar cartilage, and a thickened compact bone layer along the anterior surface of the posterior wall of the glenoid fossa. The sheep coped well with the experimental procedures and the appliance used was demonstrably effective in inducing adaptive responses in the TMJ. Consequently, it is believed that the sheep is an appropriate animal model to study growth modifications in the TMJ region.     

Induction of traumatic temporomandibular joint ankylosis in growing rats: a preliminary experimental study

Abstract –  There are many reports on the management of pediatric temporomandibular joint (TMJ) ankylosis. However, few authors have investigated the etiology of this disease in children. The purpose of this study was to determine the role of damage to both the condylar cartilage and disk in the induction of traumatic TMJ ankylosis during the growth period. The study was performed in growing rats by a common condyle fracture model. Intentional damage was performed to both the disk and condylar cartilage in the experimental group ( n  = 12), while the disk and condylar cartilage in the control group was left untouched ( n  = 12). Sham-operated growing rats were deemed the blank group ( n  = 10). Two rats from the experimental group and two from the control group were killed 24 h after the operation, and the result following surgical intervention was observed. Each rat's body weight in the three groups was monitored and recorded at 1, 2, 4, 6, 8, 10, and 12 weeks after surgery. Twelve weeks after the operation, all animals were killed. The prognosis was compared by mandible deviation measure, body weight evaluation, and histological observation. Animals from the experimental group presented a slow body weight increase and obvious mandible deviation while all involved TMJs showed fibrous ankylosis in various degrees. The damage to both the condylar cartilage and disk in the condylar fracture might play a vital role in traumatic TMJ ankylosis development during the growth period. The results of this study suggest that more attention should be paid to condylar fractures in children that are accompanied with severe cartilage and disk damage, which is a matter of significance for pediatric TMJ ankylosis prevention.     

快速原型技术在颞下颌关节重建中的应用

目的：计算机辅助软件进行颞下颌关节手术前设计,经快速原型技术制作模型,探讨该技术在下颌骨及颞下颌关节重建中的应用价值。方法：选取11例（13侧）需要进行髁突-下颌支-下颌体重建手术的患者为快速原型组,术前均进行头颅三维CT扫描（层厚0．625mm）：将DICOM格式的CT数据输入电脑软件Simplant CMF,通过软件对头颅模型进行下颌骨分离、截骨线设计、截骨及骨块移动;利用镜面反射原理,以健侧下颌骨为标准,重建患侧下颌骨;然后以重建的头颅模型为标准．对钛板进行塑形;术中根据已经塑形好的钛板,对移植骨块进行塑形,重建颞下颌关节。另选24例用传统方法进行髁突-下颌支-下颌体重建的患者作为对照组。采用SPSS13．0软件包分析2组患者手术用时,并采用两独立样本t检验：对Simplant测量出的CT扫描数据,采用配对t检验分析快速原型组内手术前、后面部对称性的差异。结果：所有患者伤口均一期愈合,无感染、出血、面神经损伤等并发症发生;术后临床及影像学检查显示,患者面形基本对称,对手术效果满意,咬合关系良好：MRI显示移植的肋骨肋软骨头均在关节窝内。手术用时传统方法平均为7．09h,快速原型组平均为5．67h．两组之间有显著性差异（P〈0．05）;应用Simplant对下颌骨CT扫描的数据进行处理,测量每个患者术后的CI（condyle—incisor）、CM（condyle—mental foramen）、CA（condyle—angle）3组变量,对健、患侧的测量数据进行配对t检验,3个指标的健、患侧均无显著差异（P〉0．05）。结论：利用快速原型技术,可以达到准确重建颞下颌关节、保持下颌骨双侧对称的目的,有利于改善术后颞下颌关节功能,提高颞下颌关节及下颌骨重建的效果。     

髁状突软骨缺损自身修复能力的实验研究

本实验研究以家兔作为实验对象，在家兔的左侧颞颌关节髁状突造成４×５ｍｍ２大小的全层软骨缺损，分别于术后２，４，８，１２和１６周处死动物，对缺损区的修复组织进行组织学和组织化学观察。结果表明：造成髁状突软骨缺损术后４至８周修复组织一度趋向透明软骨形成，但在术后８周以后开始退变，１６周时修复组织为纤维组织，纤维软骨组织或薄层无增殖能力的软骨，而不是透明软骨。由此说明：单纯髁状突软骨层切除术后其组织结构不能恢复正常。     

大鼠双侧卵巢切除后颞下颌关节的组织学研究

目的 观察成年大鼠双侧卵巢切除对颞下颌关节（ｔｅｍｐｏｒｏｍａｎｄｉｂｕｌａｒ ｊｏｉｎｔ，ＴＭＪ）组织学的影响。方法 ６８只２０周龄雌性ＳＤ大鼠分为２组，用切除是卵巢作为实验组，假手术组作为对照组。分别在术后１、２、４、８和１２周处死动物，用光镜、扫描电镜和透射电镜观察大鼠ＴＭＪ组织学变化，同时检测血清雌二醇（Ｅ２）和股骨骨密度。结果 各程期实验组血Ｅ２均明显低于对照组。１２周时，实验检测血清雌     

Juvenile diabetics' oral health and locus of control. A pilot study

The purpose of this pilot study program was to evaluate the effects of a one-year dental health education program on the oral health status and locus of control of juvenile diabetic children. Thirty subjects with juvenile diabetes mellitus were allocated to control and experimental treatment groups so that group frequencies (age, sex, race, duration of diabetes) were similar. Both groups had a Silness and Loe Plaque Index (PLI) and a Ramfjord Periodontal Disease Index (PDI) performed, and received an oral prophylaxis three times over the one-year period. Locus of control was measured at baseline and one year using the Children's Health Locus of Control Scale. In addition, the experimental group received an extensive dental health education program which emphasized the effects of dental disease on diabetes control. Twenty-five subjects completed the study. Pre- and post-locus of control measures were analyzed using the Wilcoxon Matched Pairs Signed Rank test. The Mann Whitney U Test was used to analyze differences between the groups. Indexes were compared using nonparametric two-factor repeated measures analysis of variance. Analysis revealed no statistically significant differences between groups or in locus of control scores over time. However, PDI and PLI scores improved in both groups, particularly from baseline to six months (p less than .01). Although not statistically significant, both groups exhibited a high internal locus of control. While the dental health education program resulted in only minor improvements in mean group scores, the intervention of preventive treatment produced significant improvement in measured indexes.     

A sheep model of intracapsular condylar fracture.

PURPOSE: An animal model of a condylar head fracture similar to a type B intracapsular fracture in humans was created. The effect of this model on mandibular function and morphological changes of temporomandibular joint (TMJ) structure was evaluated. MATERIALS AND METHODS: Ten sheep were divided into 3 groups, sacrificed at 1 week (2 sheep), 4 weeks (4 sheep), and 12 weeks (4 sheep) after surgery. The right side of the TMJ was considered the surgical group; the left side, the control group. The anterior and posterior attachments of the discs were cut, and an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of the condylar neck. The condyle fragment was pushed together with the disc anteriorly, inferiorly, and medially. The lateral side of the condylar stump was sutured to the capsule to limit movement. Preoperative and postoperative body weight, maximum mouth opening, lateral excursions, and x-ray and computed tomography (CT) findings in the 3 surgical groups and the control group were recorded. The SPSS software program was used for all statistical analyses. RESULTS: There were no significant differences in weight loss and left lateral movement among the 3 surgical groups, but maximum mouth opening and the right lateral movement decreased significantly in the 4-week and 12-week surgical groups. X-rays demonstrated severe bone erosion and new bony outgrowth in the lateral side of the condylar stump and a narrowed, indistinct joint space in these 2 groups. Three-dimensional reconstruction of CT images showed changed contours of the condylar stump, condylar fragment and articular eminence in all 3 surgical groups. CONCLUSIONS: This study demonstrates progressive changes toward ankylosis and pathological changes in sheep TMJ over time consistent with what has been found in humans.     

Expression of VEGF-receptors in TMJ synovium of rabbits with experimentally induced internal derangement

Our aim was to evaluate the expression of vascular endothelial growth factor receptors (VEGFRs) in the synovium of the temporomandibular joints (TMJ) of rabbits with experimentally induced internal derangement. Internal derangement was experimentally induced in 52 rabbit TMJ, and established on the right side of TMJ while the left side was used as the control. Each joint and its control was evaluated by magnetic resonance imaging (MRI) and endoscopy. The synovial tissues on both sides were harvested after one, two, three, and four weeks. The expression of VEGFRs mRNA was investigated in the experimental joint and its control using real-time polymerase chain reaction (PCR). Internal derangement was successfully confirmed in 45 of the 52 of the experimental joints (87%) on the right side by MRI and endoscopy. In the first and fourth week, the VEGFR-2 mRNA expression was higher in the experimental joints than in the controls (P = 0.008 and P = 0.02). Meanwhile, the VEGFR-1 mRNA expression was up-regulated in the experimental group compared with the controls during the fourth week (P = 0.02). However, we found no significant differences in VEGFR-3 mRNA expression in the two groups during the first and fourth weeks. During the second and third weeks, the mRNA expression of the three receptors did not differ significantly among the groups. Our data have shown increased expression of VEGFR-1 and VEGFR-2 mRNA in the synovium of rabbit TMJ with internal derangement, which indicates that VEGFR-1 and VEGFR-2 may have important roles in the processes of internal derangement and formation of adhesions.     

Comparison of the clinical outcomes of patients having sounds in the temporomandibular joint with skeletal mandibular deformities treated by vertico-sagittal ramus osteotomy or vertical ramus osteotomy

OBJECTIVE: This article describes the effects of the intraoral vertico-sagittal ramus osteotomy (IVSRO) procedure on the jaw of patients with temporomandibular joint (TMJ) disorders. STUDY DESIGN: IVSRO was performed on 15 patients (30 sides) who had mandibular protrusion or asymmetry with TMJ dysfunction. IVRO was performed on another 15 patients (30 sides). All of the 30 patients had sounds in the TMJ uni- or bilaterally. The relative positions of the condyle and disc and the range of motion of the condyles were determined by magnetic resonance imaging (MRI) before and 12 months after the operations. RESULTS: Sounds such as clicking improved in 92% (24/26) of the joints in the IVSRO group, and in 83% (20/24) of the joints in the IVRO group 12 months after the operation. The positional relationship between the condyle and disc on the MR images improved in 82% (9/11) of the joints with reduction of the anterior disc displacement; in 60% (3/5) of the joints without reduction of the anterior disc displacement in the IVSRO group; in 75% (9/12) of the joints with reduction of the anterior disc displacement; and in 40% (2/5) of the joints without reduction of the anterior disc displacement in the IVRO group. Immediately after the operation, the condyle was displaced anterio-inferiorly in all joints in both groups, but gradually returned to close to the preoperative position. There were no significant differences between the 2 groups regarding the extent of shift of the condylar head at 2 weeks and 12 months after the operation. CONCLUSION: The clinical outcomes of the IVSRO procedure are similar to those of the IVRO procedure. Therefore, IVSRO may be a suitable procedure for patients having TMJ dysfunction with skeletal mandibular deformities, particularly when an IVRO is unsuitable.