Relationship between the degree of mastoid pneumatization and the presence of persistent foramen of Huschke

The aim of this study was to determine the relationship between the degree of mastoid pneumatization and the presence of persistent foramen of Huschke (FH). Temporal computed tomography images of 714 patients (1428 ears) who applied to the Otorhinolaryngology Department of Karabuk University Training and Research Hospital between January 2016 and June 2018 were retrospectively analysed. We compared the mastoid pnomatization levels of 95 patients (74 females, 21 males, mean age 53.18 ± 15.09 years) who had persistent FH and 135 patients (103 females, 32 males, mean age 54.29 ± 15.82 years) with no FH who had similar age and gender. FH was found to be unilateral (right: 23, left: 45) in 68 (71.5%) out of 95 patients with FH, and FH was bilateral in 27 (28.4%) patients. The degree of mastoid pnomatization of the patients with FH was significantly higher than the patients without FH (p = 0.015). The degree of pneumatization of the mastoid bone may lead to persistent FH by affecting the ossification process of the tympanic segment, which has a close anatomical relationship with it.     

The foramen of Huschke: age and gender specific features after childhood

The foramen of Huschke (FH) is an aperture that is formed in the tympanic plate of the temporal bone at the age of about 1 year. The FH usually closes before the age of 5 years; but it occasionally persists throughout life. A persistent FH may result in complications such as temporomandibular joint (TMJ) herniation and salivary fistula formation, and facilitate ear injury during TMJ arthroscopy. In this study, the authors examined 1994 temporal bones from 997 Japanese dry skulls, in order to define age and gender specific features of the persistent FH after childhood. A persistent FH was found in 12% of men and in 20% of women, representing a female predominance (P < 0.0001). The incidence of a persistent FH decreased with age in both genders, suggesting that a persistent FH can close over time.     

Cone-beam computed tomographic study of the persistent foramen tympanicum according to age,sex, and skeletal patterns

This cross-sectional study evaluated the influence of prevalence, laterality and diameter of persistent foramen tympanicum (PFT) in cone beam computed tomographic (CBCT) scans of adult patients with different sagittal skeletal patterns, sex and age. CBCT of 510 patients were assessed for the presence of PFT. Skeletal pattern, age and sex of the affected patients were recorded, as well as laterality and diameter of PFT. Differences were tested using the one-way ANOVA, chi squared and paired-t tests, at α=5%. A total of 49 (9.7%) patients presented with PFT; 36 (73.5%) were women (p<0.01) aging from 31-50 years (p>0.05), with Class III skeletal pattern (p>0.05). The unilateral/bilateral ratio was 3.9:1 (p<0.01). No correlation was found between the PFT diameters with sex and age, but differences were found between the classes, with the largest diameters in Class II individuals (p=0.046). The prevalence of PFT in CBCT scans was 9.7%, with women being more affected, with unilateral defects in most cases. Skeletal patterns did not have significant effects on PFT prevalence, although PFT diameter varied among classes, with higher measures in Class II individuals.     

Computed tomography of the normal temporomandibular joint

Abstract – A study was made in two parts, retrospective (I) and prospective (II), on two samples of 36 and 17 individuals, respectively, who had temporal bone CT studies for reasons unrelated to TMJ pain and dysfunction. Groups I and II had no radiographic signs of TMJ disease and Group II had neither radiographic nor clinical signs of TMJ disease. Both groups were considered to have normal joints. Joint morphometrics for the two groups (I/II) were as follows; transverse condylar dimensions were 18.5/18.1 mm. Condylar angulation averaged 24°/25° and intercondylar distance averaged 83/83 mm while extra condylar distance averaged 118/118 mm. The condyle in the sagittal plane showed a smooth and rounded form with anterior-superior joint space averaging 1.9/1.7 mm while the central-superior joint space averaged 2.3/2.2 mm. The medial-horizontal joint space averaged 3.9/3.7 mm. The slope of the central portion of the articular eminence averaged 60°/60° in the sagittal plane.     

Quantitative bone imaging biomarkers to diagnose temporomandibular joint osteoarthritis

Bone degradation of the condylar surface is seen in temporomandibular joint osteoarthritis (TMJ OA); however, the initial changes occur in the subchondral bone. This cross-sectional study was performed to evaluate 23 subchondral bone imaging biomarkers for TMJ OA. The sample consisted of high-resolution cone beam computed tomography scans of 84 subjects, divided into two groups: TMJ OA (45 patients with TMJ OA) and control (39 asymptomatic subjects). Six regions of each mandibular condyle scan were extracted for computation of five bone morphometric and 18 grey-level texture-based variables. The groups were compared using the Mann–Whitney U-test, and the receiver operating characteristics (ROC) curve was determined for each variable that showed a statically significance difference. The results showed statistically significant differences in the subchondral bone microstructure in the lateral and central condylar regions between the control and TMJ OA groups (P <  0.05). The area under the ROC curve (AUC) for these variables was between 0.620 and 0.710. In conclusion, 13 imaging bone biomarkers presented an acceptable diagnostic performance for the diagnosis of TMJ OA, indicating that the texture and geometry of the subchondral bone microarchitecture may be useful for quantitative grading of the disease.     

颞下颌关节骨关节病不同分期的锥形束CT三维位置比较

目的 探讨颞下颌关节骨关节病（TMJOA）患者在不同骨关节病分期髁突三维影像学特征的差异。方法 以2005年马绪臣等提出的骨关节病X线表现分期为标准,将108例TMJOA患者（骨关节病组）的锥形束CT（CBCT）检查结果分为4期,对照组为28例仅存在间隙改变的颞下颌关节紊乱病患者;评价TMJOA CBCT征象不同分期时髁突的矢状面位置,并对2组的髁突水平角进行比较。结果 TMJOA不同分期髁突矢状面位置无统计学差异,但髁突水平角有统计学差异（F=3.872,P=0.005）,进一步两两分析表明,第1期髁突水平角低于第2和3期（P=0.027,P= 0.000）;第2期对照组髁突水平角低于第3期（P=0.004,P=0.047）。结论 TMJOA患者在不同分期时髁突矢状面位置差异不明显,但髁突水平角存在差异,该角度的变化对TMJOA的分期有一定提示意义。     

Observation of three cases of temporomandibular joint osteoarthritis and mandibular morphology during adolescence using helical CT

Temporomandibular joint (TMJ) osteoarthritis (OA) is a potential cause of craniofacial deformity. If TMJ OA appears during orthodontic treatment, the mandible usually rotates posteriorly, resulting in an unsatisfactory profile, especially in patients with pre-treatment mandibular retrusion. Although it is important to confirm the kind of TMJ pathosis at the start of orthodontic treatment, the relationship between TMJ OA, condylar remodelling and changes in craniofacial morphology remains unclear because of a lack of longitudinal studies. Elucidating this relationship might allow better prediction of post-treatment craniofacial morphology. In the present case reports, helical computed tomography and cephalometry were used to analyse relationships between the pattern and location of condylar remodelling and the changes in craniofacial morphology in three patients with TMJ OA.     

Study on the lateral pterygoid muscle status after artificial temporomandibular joint replacement

The purpose of this study was to explore the status of the lateral pterygoid muscle (LPM) after detachment in artificial temporomandibular joint replacement (TJR) surgery. Patient clinical and computed tomography imaging data were collected before and after unilateral artificial TJR with LPM detachment. The volume of the LPM on the operated and unoperated sides was measured before and after surgery (at 1, 3, 6, 12 months) using ProPlan CMF 3.0 software. The volumes of the LPM on both sides, the patient’s mandibular movements, quality of life (QoL), and pain and diet scores (visual analogue scales) were evaluated and compared at the different follow-up stages. Ten patients were included in the study. After surgery, the volume of the operated LPM was significantly reduced to 60.78% at 3 months (P = 0.007), and gradually stabilized to 51.58% at 6 months (P = 0.025) and 54.68% at 1 year postoperative (P = 0.002). There were no significant LPM volume changes on the unoperated side (P = 0.67). Lateral movement of the operated joint was significantly reduced (P = 0.021) and correlated with the LPM volume change after surgical detachment (P = 0.042). The LPM shrank after detachment in the artificial TJR surgery and the muscle detachment affected the movement of the replaced joint.     

Association between temporomandibular joint disc position evaluated by magnetic resonance imaging and mandibular condyle inclination evaluated by computed tomography

Temporomandibular joint disc displacement is common in the world's population and could be associated with bone and functional characteristics of the temporomandibular joint. The aim of these study was to analyse the association between temporomandibular joint disc position evaluated by magnetic resonance imaging (MRI) and the inclination of the mandibular condyle evaluated by computed tomography (CT). One hundred and seventy temporomandibular joints (TMJ) were retrospectively analysed. The temporomandibular disc position was evaluated by MRI and classified into three types: normal (N), disc displacement with reduction (DDWR) and disc displacement without reduction (DDWoR). The mandibular condyle measurements evaluated by CT included horizontal, sagittal and coronal inclination. ANOVA followed by post hoc Tukey's test was used to evaluate the interaction between condylar inclination and disc position. There was an association between disc position and the horizontal and sagittal condylar inclination (P < .05). There are statistically significant differences in the mean of horizontal and sagittal inclination of the mandibular condyle between the DDWoR and the other disc positions (P = .002 and P = .004). Disc position was not statistical associated with coronal inclination of condyle (P > .05). These results indicate that the inclination of the mandibular condyle may be different in TMJ with various disc position. A more medial horizontal inclination and a more posterior sagittal inclination of the mandibular condyle are associated with DDWoR.     

开(牙合)与颞下颌关节紊乱病

开患者的颜面形态、吞咽模式、咀嚼肌力平衡、下颌运动模式都有特殊之处,目前的研究对开与颞下颌关节紊乱病之间的相互促进作用和因果关系还不完全清楚。本文从开患者的颅面形态、咀嚼肌力、吞咽模式等几个方面对开和颞下颌关节紊乱病的相互关系进行综述。     

颞下颌关节渗出液与关节疼痛关系的研究

目的:评价关节疼痛与渗出液的关系。方法:对44例单侧关节疼痛TMD患者88侧关节,完成闭口矢状位T2加权成像,以非疼痛侧作为自身对照,观察关节渗出液发生率;利用VAS进行疼痛程度的判定,比较疼痛侧渗出液组与无渗出液组有无差异。结果:44个疼痛关节中,26个关节(59.1%)存在渗出液;而44个非疼痛关节中,仅7个关节(15.9%)存在渗出液,经统计学分析,TMJ疼痛与渗出液有显著相关性(P<0.005),将少量渗出液视为无渗液,进一步统计分析发现疼痛与渗出液仍有相关性;在44个疼痛关节中,渗出液组患者及无渗出液组患者VAS平均值分别为46.5±25.1和39.7±22.8,经t检验两组间差别无统计学意义。结论:渗出液为关节疼痛原因之一,但其与关节疼痛程度无关。     

Computerized axial tomography in the diagnosis of internal derangements of the temporomandibular joint

Fourteen patients with a history of pain, clicking and locking of the temporomandibular joint were assessed clinically and by using computerized axial tomography (CAT). The findings of the clinical and CAT scan assessment were correlated and compared with surgical observations. Computerized axial tomography scanning proved to be a highly accurate method of assessing meniscal position. With the advent of more sophisticated methods of CAT scanning, it provides an accurate, non-invasive method of assessing the temporomandibular joint and providing a basis for more effective treatment planning of problems related to internal derangements.     

Evaluation of the visibility and the course of the mandibular incisive canal and the lingual foramen using cone‐beam computed tomography

Objectives: To assess the visibility and the course of the incisive canal and the visibility and the location of the lingual foramen using cone‐beam computed tomography (CBCT). Methods: In total, 100 CBCT examinations of patients for preoperative planning were used for this study. The examinations were taken using the NewTom 3G CBCT unit, applying a standardized exposure protocol. Image reconstruction from the raw data was performed using the NewTom software. Three experts were asked to assess the visibility of the incisive canal using a four‐point rating scale. The position of the incisive canal was recorded in relation to the lower, buccal and lingual border of the mandible using the application provided by the CBCT software. Results: The incisive canal was definitely visible in 83.5% of the scans and the mean endpoint was approximately 15 mm anterior to the mental foramen. The mean distance from the lower border of the mandible was 11.5 mm and its course was closer to the buccal border of the mandible in 87% of the scans. The lingual foramen was definitely visible in 81% of the scans. Conclusions: The high detection rate of the incisive canal and the lingual foramen in the anterior region of the mandible using CBCT indicates the potentional high preoperative value of CBCT scan for surgical procedures in the anterior mandible. To cite this article :
Makris N, Stamatakis H, Syriopoulos K, Tsiklakis K, van der Stelt PF. Evaluation of the visibility and the course of the mandibular incisive canal and the lingual foramen using cone‐beam computed tomography.
Clin. Oral Impl. Res. 21 , 2010; 766–771.
doi: 10.1111/j.1600‐0501.2009.01903.x     

The many faces of the genetics contribution to temporomandibular joint disorder

OBJECTIVES: Review the literature on candidate genes for temporomandibular joint disorder (TMD). Setting and Sample Population - Literature review. MATERIALS AND METHODS: Two basic approaches were used to obtain literature in any language regarding genes and TMD. First, Medline, Embase, and Science Citation Index databases were searched using the keywords 'temporomandibular joint disorder' and 'temporomandibular joint dysfunction' for studies published from 1966 to 2007. Then, the references list of the studies obtained in the database was also considered. RESULTS: Candidate genes for TMD include genes for individual variations in pain perception, gender and ethnicity, proinflammatory cytokines, female hormones, breakdown of extracellular matrix, and syndromic forms of TMD. CONCLUSION: Most of the studies on genetic variation contributing to TMD are approaching the disease mainly from an immune-inflammatory perspective. Recent investigations of the genetic variables which may predict identifiable levels of pain perception may uncover new approaches to our traditional treatment modalities for the chronic pain patient.     

54例正常人双侧颞下颌关节CBCT测量值分析

目的：探讨应用CBCT（cone-beamcomputedtomography）对成年人两侧颞下颌关节进行多项指标数据测量分析。方法：在TMJ成像与测量技术的基础上,筛选出正常成人54例,通过严格的TMJ临床检查确定为健康关节,利用Newtom9000CBCT对其ICP位颞下颌关节进行成像后测量分析。结果：在轴位测得髁状突水平角以及单侧髁状突距矢状中线的距离;平行于髁状突长轴的斜位,测髁状突长轴径,垂直角度,沿髁状突长轴顶内外极间任意角间隙宽度;垂直于髁状突长轴的斜位测量关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度;矢状位测关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度。结论：正常成人双侧髁状突位置及关节窝形态性别差异不明显,双髁状突位置及关节窝形态基本对称。