Vertical force and torque analysis during mechanical preparation of extracted teeth using hand ProTaper instruments.

The purpose was to measure and analyse the vertical force and torque developed in the wider and narrower root canals during hand ProTaper instrumentation. Twenty human incisors were divided in two groups. Upper incisors were experimental model for the wide, while the lower incisors for the narrow root canals.

Relations between anterior permanent teeth, dental arches and hard palate.

The width and length of the anterior teeth, the dimensions of the frontal dental arches and the dimensions of the hard palate were measured (24 men and 56 women, age range of 18-30 years). The results showed gender-related dimorphism only for the cervical width of the maxillary canine, which were wider in men, p < 0.05.

Vibrations produced during erbium:yttrium-aluminum-garnet laser irradiation.

The purpose of this study was to evaluate vibrations induced by an erbium:yttrium-aluminum-garnet (Er:YAG) laser in the non-contact mode and compare the vibrations with different pulse durations and energy parameters. The experiment was conducted on an extracted tooth built up in silicone impression material. The vibrations were measured by piezoelectric accelerometer for a super-short pulse (SSP), a very short pulse (VSP), and a short pulse (SP) at a frequency of 5 Hz for 1 s.

3-D stress analysis in first maxillary premolar.

The aim of this study was to investigate the stress distribution in a 3-D model of two-rooted tooth (first maxillary premolar) under two different occlusal force vectors by using finite element analysis. In the first model overall force of 200 N was divided into three vectors (cusp to fossa occlusion), and in the second model overall force was divided into 4 vectors (cusp to fossa and cusp to marginal ridge occlusion). The greatest compressive stress was found at the dentino- enamel junction in the cervical area of the both models (about -200 MPa).

Tumor necrosis factor-alpha and interleukin 6 in human periapical lesions.

Aim: The aim of this study was to evaluate the presence of the cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in human periapical lesions.

Subjects And Methods: Samples were obtained from three groups of teeth: symptomatic teeth, asymptomatic lesions, and uninflamed periradicular tissues as a control.

Results: TNF-alpha levels were significantly increased in symptomatic lesions compared to control.

Cell death and cell proliferation in mouse submandibular gland during early post-irradiation phase.

The effects of irradiation on different cell compartments in the submandibular gland were analyzed in adult C57BL/6 mice exposed to X-ray irradiation and followed up for 10 days. Apoptosis was quantified using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick end labeling method (TUNEL). Cell proliferation was detected using immunohistochemistry for proliferating cell nuclear antigen (PCNA).

Early and late effects of X-irradiation on submandibular gland: a morphological study in mice.

Background: Radiotherapy for head and neck cancers causes permanent salivary gland dysfunction and xerostomia. The aim of this study was to determine changes in mice submandibular glands after X-irradiation.

Methods: The submandibular glands of male C57BL/6 mice were locally X-irradiated in the head and neck region with a single dose of 7.

The cytotoxicity of RoekoSeal and AH plus compared during different setting periods.

The aim of this study was to evaluate the cytotoxicity of the root canal sealers RoekoSeal Automix (RSA) and AH Plus in vitro on human cervical carcinoma (HeLa) cells and mouse skin fibroblasts (L929). The sealers were covered with a 3 x 10(4) cell suspension 1 h, 24 h, 48 h, 7 days and 1 month after mixing. Four samples and respective controls without sealer were prepared.

Odontogenic sinus tract to the neck skin: a case report.

We describe a 22-year-old woman with neck skin sinus tract that developed as a consequence of dental infection. The patient was treated twice in an inappropriate way with recurrence of the sinus tract. We opted for an extraction of the tooth.