Comparative cone-beam computed tomography evaluation of the osseous morphology of the temporomandibular joint in temporomandibular dysfunction patients and asymptomatic individuals

We examined the bone components of the temporomandibular joint (TMJ) in asymptomatic individuals and patients with temporomandibular dysfunction (TMD) using cone-beam computed tomography (CBCT). Two hundred asymptomatic individuals and 200 patients with TMD were included in this study. Condyle position, eminence height, eminence inclination, condyle shape, and fossa shape were assessed on CBCT images of the 800 temporomandibular joints. The eminence inclination (P < 0.05), eminence height (P < 0.0001), mediolateral width of condyle (P < 0.0001), and anterior joint space (P < 0.0001) were significantly greater in male subjects compared with female subjects in both the asymptomatic group and TMD group. Comparisons of the asymptomatic group and TMD group revealed significant differences in the anterior joint space (P < 0.0001), ratio of anterior joint space to posterior joint space (P < 0.001), posterior joint space (P < 0.05), eminence inclination (P < 0.05), eminence height (P < 0.05), condyle shape (P < 0.0001), and fossa shape (P < 0.05). The present analyses suggest that a steeper articular eminence inclination may be risk factor for TMD. The presence of TMD was associated with the condyle position in the TMJ

Ectopic premolar tooth in the sigmoid notch

Impaction of a mandibular premolar is relatively uncommon. Ectopic placement is more unusual and there has been no discussion in the literature of an ectopic mandibular premolar in the coronoid process. In this case report, we present an impacted ectopic mandibular permanent premolar in the sigmoid notch (incisura mandibulae) region. Etiology of the tooth and treatment options are discussed and illustrated by Cone Beam Computed Tomography (CBCT) images

A stereological study of the effects of mercury inhalation on the cerebellum

Mercury in the environment that arises from organic and inorganic sources can cause irreversible damage to the nervous system. Toxicity may be direct or may arise from interactions with other metals in the environment. We evaluated the possible effects of mercury vapor on rat cerebellum. Twelve adult female rats were divided into control and experimental groups. The rats in the experimental group were exposed to mercury vapor for 9 h/day for 45 days. Cerebellar tissue samples were evaluated using stereology and for histopathology. The total number of Purkinje cells was estimated using a physical disector method. We found that in the experimental group, overall volume decreased and the number of Purkinje cells was reduced. We also found cellular damage including pycnotic nuclei, eosinophilic cytoplasm and vacuolization; these features were absent in the control group. We found that chronic exposure to inorganic mercury vapor is toxic to the cerebellum

Inhalation of mercury vapor can cause the toxic effects on rat kidney

Dental amalgam has been used in dentistry as a filling material. The filler comprises mercury (Hg). It is considered one of the most important and widespread environmental pollutants, which poses a serious potential threat for the humans and animals. However, mercury deposition affects the nervous, cardiovascular, pulmonary, gastrointestinal, and especially renal systems. In most animals' species and humans, the kidney is one of the main sites of deposition of mercury and target organ for its toxicity. In this study, the effects of mercury intake on kidney in rats were searched. For the this purpose; we used 24 adult female Wistar albino rats (200g in weight) obtained from Experimental Research and Application Center of Ataturk University with ethical approval. Besides, they were placed into a specially designed glass cage. Along this experiment for 45 days, subjects were exposed to (1mg/m(3)/day) mercury vapor. However, no application was used for the control subjects. At the end of the experiment, kidney samples were obtained from all subjects and processed for routine light microscopic level and stereological aspect were assessed. Finally, according to our results, mercury affects the histological features of the kidney. That means, the severe effects of mercury has been shown using stereological approach, which is one of the ideal quantitative methods in the current literature. In this study, it was detected that chronic exposure to mercury vapor may lead to renal damage and diseases in an experimental rat model

Effect of mercury vapor inhalation on rat ovary: stereology and histopathology

AimMercury, an environmental contaminant, is a risk factor for health in whole living organisms. In this study, we investigated whether mercury vapor (HgO) inhalation has an effect on rat ovary. MethodsTwelve Wistar albino rats were divided equally into experimental (Hg) and control groups (n = 6). Animals in the Hg group were exposed to HgO for 45 days at a dose 1 mg/m(3)/day, after which, histological and stereological assessment were carried out. ResultsOvaries exposed to HgO had histo-morphometric alterations. HgO inhalation resulted in reduction of the total number of primordial, primary and Graaf follicles. Also, mean volume of ovary, medulla and cortex, corpus luteum (c.luteum) and Graaf follicles was decreased in the Hg group. Moreover, there was a significant increase in total volume of the atretic follicles. On light microscopy, thickening of tunica albuginea, increase of fibrils within the connective tissue, congestion of the capillaries and venous vessels, thinned walls and fibrin deposition in some large blood vessels, and edema were seen. Also, irregular follicle and oocyte borders, and hydropic degeneration in follicular granulosa cells were detected. ConclusionStructural alterations could be attributed to the toxic influence of HgO on rat ovary. The use of Hg should therefore be more controlled to minimize its toxic effect

A stereological and histopathological study of the effects of exposure of male rat testes to mercury vapor

Mercury is ubiquitous in the environment; it is an occupational pollutant and a potential toxicant. We investigated the effects of exposure of rat testes to mercury vapor (Hg-0). Twelve male rats were divided into two groups of six: the rats of the Hg-0 group were exposed to mercury (1 mg/m(3)/day) in a chamber for six weeks; the control group rats were housed under the same conditions without exposure to Hg-0. After the experimental period, the testes were removed, sections of testis were evaluated histopathologically after hematoxylin and eosin staining, and stereologically using the Cavalieri principle and optical fractionator methods. We found significant decreases in the total volume of testis, diameters of seminiferous tubules and total volume of seminiferous tubules. Significant decreases were detected in the numbers of Sertoli cells, spermatogonia, spermatocytes and spermatids of the Hg-0 group compared to the control group. In the Hg-0 exposed group, spermatogenic cells were degenerated and seminiferous tubules were atrophied.This study was supported by Ataturk University Scientific Project Fun

Urine and saliva iodine levels in patients with dental caries and normal healthy volunteers

The aim of this study was to investigate the iodine concentration in the urine and saliva of patients with dental caries and of healthy volunteers in Erzurum, Turkey. Urine and saliva specimens were obtained from 29 patients, who have dental caries and from 26 healthy volunteers. The iodine concentration in the urine of patient's with dental caries was found to be 7.50 +/- 2.68 mu g/dl, which was lower than the urinary iodine level of healthy persons, which was found to be 12.02 +/- 3.16 mu g/dl (p < 0.0001). Similarly, the saliva iodine level of patients with dental caries was lower than that of healthy volunteers, beeing 4.42 +/- 2.21 mu g/dl, 8.28 +/- 2.78 mu g/dl, respectively (p < 0.0001). There was a positive correlation between urinary iodine level and saliva iodine level in both groups (r = 0.750, p < 0.001; r = 0.519, p < 0.001). There was, however, no significant difference in iodine levels of urine and saliva between males and females for both groups of subjects. A positive correlation between iodine levels in urine and saliva of patients and healthy volunteers was also observed. Our results suggest that iodine concentration in urine and saliva might be an indication for dental cavity, where iodine supplementation could be considered as a way of prophylaxis