Lubricin Immunohistochemical Expression in Human Temporomandibular Joint Disc with Internal Derangement

Lubricin is a chondroprotective, mucinous glycoprotein which contribute to joint lubrication, especially to boundary lubrication and maintains joint integrity. The present investigation aimed to study the immunolocalization of lubricin in TMJ discs from patients affected by anterior disc displacement with reduction (ADDwR) ADDwoR. Eighteen TMJ displaced disc affected by ADDwoR were processed immunohistochemically, with a polyclonal anti‐lubricin antibody, used at 1:50 working dilution. The percentage of lubricin immunopositive cells (extent score = ES) and the extent of lubricin staining of the disc extracellular matrix (ECM), were evaluated. Each sample was scored for histopathological changes. Percentage of immunostained surface disc cells was the same (ES = 4) in both control and ADDwOR cells, being this data not statistically significant (P \u3c 0.05). In pathological specimens the percentages of lubricin‐stained cells was very high with an ES of 4 respect to control specimen, and this difference was statistically significant different (P \u3e 0.05). The extracellular matrix (ECM) of discs at the disc surfaces of both pathological and normal specimens was very heavily stained (++++). Both the ES and ECM staining were not statistically correlated to the TMJ degeneration score according to the Spearman’s rank correlation coefficient. According to our findings, a longstanding TMJ disc injury, affects lubricin expression in the TMJ disc tissue and not its surfaces, moreover, lubricin immunostaining is not correlated to TMJ disc histopathological changes

Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor versus pen

To define if the new portable appliances, like smartphone, iPad, small laptop and tablet can be used in cephalometric tracing without dropping out the validity of any measurement. METHODS:We investigated and compared the reproducibility and the speed of landmarks identification process on lateral X-rays in two input devices: a mouse-driven cursor and a pen used as input means in mobile devices. One expert located 22 landmarks on 15 lateral X-rays in a repeated measure design two times, at time T1 and T2, after at least one month. The Intraclass Correlation coefficient was used to evaluate the reproducibility for each landmark tracing and the agreement between the value derived from both input devices. Also, the mean errors in measurements, the standard deviation and the Friedman Test significans (P < 0.05) between both input were statistically evaluated. RESULTS:All landmarks had a high agreement and the Friedman Test indicated statistically significant differences (P<0.05) for the identification of Na, Po, Pt, PNS, Ba, Pg, Gn, UIE, UIA, APOcc and PPOcc landmarks. CONCLUSIONS:Even if the mouse input give higher agreement for landmark tracing the differences are really minimal and they can be ignored in private practice. We suggest the adequacy of pen input in clinical setting

Apoptosis in Displaced Temporomandibular Joint Disc with and without Reduction: An Immunohistochemical Study

Internal derangement (ID) of the temporomandibular joint (TMJ) is due to an abnormal relationship of the articular disc to the mandibular condyle, glenoid fossa and articular eminence. The two most common types of internal derangement are anterior disc displacement with (ADDwR) and without reduction (ADDwoR). Disc displacement is associated with degenerative tissue changes. The histological features of discs from patients with TMJ ID reflect a general remodelling caused by abnormal loading. A correlation has been demonstrated between TMJ ID and apoptosis. Few investigations have addressed the role of apoptosis or caspase activity in TMJ ID. The apoptosis activation process was studied in different areas of discs from 18 patients with ID (both ADDwR and ADDwoR) and four cadavers (controls), with emphasis on the expression of caspase 3, whose activation makes the death process irreversible. The results showed a greater proportion of caspase 3‐positive cells in ADDwR and ADDwoR than in control discs. Immunopositivity also varied between disc areas; in particular, in ADDwoR sections labelled cells were significantly more numerous (P \u3c 0.01) in the posterior disc attachment than in the anterior and intermediate bands. In addition, a significantly greater proportion of labelled cells was seen in the anterior (+) and intermediate (++) band of ADDwR compared with ADDwoR discs both bands (P \u3c 0.05). These data suggest the importance of programmed cell death in the progression of TMJ ID

Occurrence and Regional Distribution of TRAIL and DR5 on Temporomandibular Joint Discs: Comparison of Disc Derangement with and without Reduction

Background Tumor necrosis factor (TNF)–related apoptosis-inducing ligand (TRAIL) is an apoptosis-inducing member of the TNF gene family which triggers apoptotic signals by interaction with its receptors. It has been suggested to be a major contributing factor to tissue degeneration. Objective The present study investigated, through immunohistochemistry, the regional expression of TRAIL and in temporomandibular joint (TMJ) disc of anterior disc displacement with reduction (ADDwR) and without reduction (ADDwoR) patients, to help determine the relationship between TMJ disc displacement and apoptosis. Study design We studied 18 TMJ diseased discs affected by disc displacement without or with reduction and 4 normal TMJ discs. Specimens were processed for immunohistochemistry to evaluate TRAIL and its receptor DR5 expression. Results Disc tissues from internal derangements (both ADDwR and ADDwoR) exhibited a much higher percentage of TRAIL- and DR5-positive cells as well as stain intensity compared with normal tissue though with regional variation according to the portion of the disc. There was a significantly higher percentage of stained cells in the posterior disc attachment compared with the anterior or intermediate bands of both ADDwR and ADDwoR discs for TRAIL and DR5. Conclusions TRAIL and DR5 are overexpressed in displaced human TMJ disc, especially in the posterior disc attachment. These results suggest a possible pivotal role of the TRAIL/DR5 system in TMJ disc degeneration

An Evaluation of Cellular Neural Networks for the Automatic Identification of Cephalometric Landmarks on Digital Images

Several efforts have been made to completely automate cephalometric analysis by automatic landmark search. However, accuracy obtained was worse than manual identification in every study. The analogue-to-digital conversion of X-ray has been claimed to be the main problem. Therefore the aim of this investigation was to evaluate the accuracy of the Cellular Neural Networks approach for automatic location of cephalometric landmarks on softcopy of direct digital cephalometric X-rays. Forty-one, direct-digital lateral cephalometric radiographs were obtained by a Siemens Orthophos DS Ceph and were used in this study and 10 landmarks (N, A Point, Ba, Po, Pt, B Point, Pg, PM, UIE, LIE) were the object of automatic landmark identification. The mean errors and standard deviations from the best estimate of cephalometric points were calculated for each landmark. Differences in the mean errors of automatic and manual landmarking were compared with a 1-way analysis of variance. The analyses indicated that the differences were very small, and they were found at most within 0.59 mm. Furthermore, only few of these differences were statistically significant, but differences were so small to be in most instances clinically meaningless. Therefore the use of X-ray files with respect to scanned X-ray improved landmark accuracy of automatic detection. Investigations on softcopy of digital cephalometric X-rays, to search more landmarks in order to enable a complete automatic cephalometric analysis, are strongly encouraged

Rapid Maxillary Expansion Affects the Spheno-occipital Synchondrosis in Youngsters A Study with Low-Dose Computed Tomography

Objective: To test the null hypothesis that the spheno-occipital synchondrosis does not show bony displacement in response to rapid maxillary expansion (RME) therapy in youngsters. Materials and Methods: A total of 16 computed tomography (CT) records were taken from 8 growing patients (2 males and 6 females), before (TO) and after (T1) treatment with RME. All patients had been diagnosed originally with transverse maxillary deficiency. The mean chronological age of the patients was 9.8 +/- 1.8 years (range, 8 to 11.4 years). High-resolution multislice multidetector CT was used to study quantitatively the extent of the opening of the spheno-occipital synchondrosis following RME. A low-dose CT scan protocol was used (80 kV, 10 mA) and the data file of each patient was transferred to a workstation where the anteroposterior width of the spheno-occipital synchondrosis was measured on axial images. Results: Before treatment with RME (TO), the anteroposterior mean width of the spheno-occipital synchondrosis was 1.73 +/- 0.46 mm immediately after the active phase of expansion (T1), and the width of the synchondrosis increased to 2.30 +/- 0.47. This difference was statistically significant according to the Wilcoxon signed rank test (P < .05). Conclusion: Rapid maxillary expansion leads to a small immediate widening of the sphenooccipital synchondrosis in youngsters. (Angle Orthod. 2010;80:106-110.

Effectiveness of the passive lingual arch for E space maintenance in subjects with anterior or posterior rotation of the mandible: a retrospective study.

Objective: The aim of this study was to determine whether or not lingual arches in subjects with anterior or posterior mandible rotation can produce different effects in the prevention of first permanent molar mesial migration. Subjects and Methods: Forty-two patients with a mean age of 9 ± 0.8 years were selected from the Department of Orthodontics, University of Catania, Italy. These subjects were treated with a passive mandibular fixed lingual arch. The sample was divided into 3 groups according to the gonial angle in order to establish the pattern of mandible growth: mandibular posterior rotation (MPR), mandibular growth in straight-downward direction (MSD) and mandibular anterior rotation (MAR). Lateral cephalograms and study models of the patients before and after treatment were examined to determine any positional changes of the mandibular first molars and incisors. Results: Statistically significant differences between the MPR group and the other 2 (MSD and MAR) were found as regards mandibular first molar and incisor positional changes. No significant differences were found between the MSD and MAR groups. Conclusion: The results indicate that the effect of lingual arch is influenced by mandibular growth patterns. In patients with MPR, the lingual arch preserves arch length but the mesial migration of first permanent molars is not completely blocked

TRAIL, DR5 and Caspase 3-dependent Apoptosis in Vessels of Diseased Human Temporomandibular Joint Disc. An Immunohistochemical Study

To evaluate the apoptosis involvement in the angiogenesis as a self-limiting process in patients with temporomandibular joint (TMJ) degenerated disc vessels, we assessed, by immunohistochemistry, the detection of TRAIL, its death receptor DR5 and caspase 3. TRAIL, its death receptor DR5 and caspase 3 expression were studied by immunohistochemistry in 15 TMJ discs displaced without reduction and in 4 unaffected discs. These apoptosis molecules were detected in the intima and media layers of newly formed vessels affected discs. In conclusion, vessels apoptosis activation in TMJ disc with ID could be regarded as a self-limiting process that try to leads to vessel regression; in this way an inhibition of angiogenic vessels may prove a key strategy in limiting pathological angiogenesis, by cutting off blood supply to tumors, or by reducing harmful inflammation

Skeletal Anomalies and Normal Variants in Patients with Palatally Displaced Canines

Objective: To test the null hypothesis that there is no increased prevalence of skeletal anomalies and/or normal variants as evidenced by the cephalometric radiographs of patients with palatally displaced canines (PDC). Materials and Methods: The treatment records of 38 white subjects between 14 and 20 years old with PDC were collected and evaluated retrospectively. Inclusion criteria for the study required that the case records include good-quality panoramic radiographs and lateral cephalometric radiographs with the first four cervical vertebrae clearly visible. The anomalies recorded for each case included sella bridge, atlanto-occipital ligament calcification or ponticulus posticus, and posterior arch atlas deficiency. A control group consisted of 70 consecutively treated subjects who had no other dental anomalies and whose maxillary canines had erupted normally. Fisher's exact test and Pearson's chi-square test were used to determine possible statistically significant differences in the incidence of skeletal anomalies and/or normal variants between the group of patients with PDC and the control group. Results: The prevalence of skull anomalies and normal variants seen in cephalometric radiographs was increased in patients with PDC. Because of the presence of ponticulus posticus (Pearson's chi-square, P < .050; Fisher's exact test, P < .052), sella bridge (Pearson's chi-square, P < .042; Fisher's exact test, P < .042), and posterior arch deficiency (Pearson's chi-square, P < .047; Fisher's exact test, P < .039), statistically significant differences were observed between subjects with PDC and the control group. Conclusions: The null hypothesis was rejected. There is an increased prevalence of skull skeletal anomalies and/or normal variants in patients with PDC. (Angle Orthod. 2009;79:727-732.

Soft Tissue Changes Following the Extraction of Premolars in Nongrowing Patients With Bimaxillary Protrusion

Objective: To quantify the amount of perioral tissue changes following the extraction of four premolars in patients with bimaxillary protrusion who had nearly completed active growth. Materials and Methods: A literature search was conducted to identify clinical trials that assessed cephalometric perioral soft tissue changes in patients affected by biprotrusion and treated with extractions. Electronic databases (PubMed, ISI WoS Science Citation Index Expanded, and HubMed) were searched. Abstracts that appeared to fulfill the initial selection criteria were selected, and the full-text original articles were retrieved and analyzed. Only articles that fulfilled the final selection criteria were finally considered. Their references were also hand-searched for possible missing articles from the database searches. Results: Nine abstracts met the initial inclusion criteria and these articles were retrieved. From these, five were later rejected mostly because the sample dealt with growing subjects. Four articles remained and they showed that the upper and lower lips retracted and the nasolabial angle increased following premolar extraction. Upper lip retraction ranged from 2 mm to 3.2 mm, lower lip retraction ranged from 2 mm to 4.5 mm. Conclusions: The lip procumbency improves following the extraction of four premolars and this improvement is predictable. However, the changes are small and do not dramatically modify the profile. A "dished in" profile is not to be expected. Individual variation in response is large. (Angle Orthod 2010;80:211-216.