1,721,035 research outputs found
A new histological method to study oral soft tissue penetrability to iodine and optimize oral use of iodine solutions
No full textThe aim of this work is to establish a histological method to fix iodine inside slides of treated oral mucosa more permanently in order to allow section counterstaining and facilitate improved clinical and experimental studies on iodine penetration. Transforming iodine into a stable histological formation inside tissues is particularly useful for histological analysis of clinical and experimental iodine treatments. In the field of oncology, this method can be applied to povidone-iodine-treated (human or animal) mucosa or skin, to organs treated with iodine tincture or Lugol’s solution, to oral lesion detection and to mucogingival junction identification
Histomorphometric study of bone reactions during orthodontic tooth movement in rats
No full textThe biological response to orthodontic tooth movement has generally focused on reactions within the periodontal ligament (PDL), whereas less attention has been paid to the behavior of neighboring bone. The purpose of the study was to describe the influence of orthodontic force on bone surrounding the displaced tooth and the adjacent, untreated teeth. Bone changes in relation to treatment time and different sites were investigated. A mesial tipping of the left maxillary first molar was obtained from 54 adult male Wistar rats. Oxytetracycline was injected subcutaneously 48 h before killing, which took place after 4, 7, or 14 days. The maxilla was fixed in paraformaldehyde and embedded undecalcified in methylmethacrylate. A set of thick horizontal sections was taken from the cervical, intermediate, and apical levels of the roots. The sections were microradiographed and analyzed microscopically under bright-field and fluorescent illumination. Bone fraction and PDL width was measured using a Zeiss Videoplan device equipped with an overlay system. New bone formation was detected by oxytetracycline labels. The analysis showed a consistent, significant decrease of the alveolar bone fraction around both displaced and adjacent teeth at all treatment times. Apposition, indicated by the tetracycline uptake, was found on the periosteal side of the treated hemimaxilla and, after 14 days, also on the surface toward which the tooth was moving and around the adjacent teeth. These results suggest that a time rather than a space relationship exists between bone resorption and formation and that the whole hemimaxilla reacts to the mechanical challenge, resembling the regional acceleratory phenomenon (RAP) observed in other circumstances. Copyright (C) 1999 Elsevier Science Inc
Morphological, histochemical and immunocytochemical study of CO2 and Er:YAG laser effect on oral soft tissues
No full textThe purpose of this study was to investigate the morphological, histochemical, and immunocytochemical
changes of the oral mucosa after CO2 or Er:YAG laser irradiation. Background Data: There have
been no comparative reports on CO2 and Er:YAG laser effects on human oral soft tissues. Materials and
Methods: Tissue preservation was studied in 40 oral biopsies of young patients obtained by CO2 and Er:YAG
laser surgery. Hematoxylin-eosin and Giemsa stains, PAS/diastase treatment, AE1 and AE2 cytokeratins,
MiB1/Ki67, and bcl-2 immunoreactions were performed on the laser cut edges on formalin fixed, paraffin embedded
biopsies. Results: CO2 laser biopsies show blisters, clefts and erosions of the epithelium. Intracellular
edema and lengthened nuclei were also seen. The glycogen content results decreased in CO2 laser biopsies.
Good expression for cytokeratins and cell-cycle proliferation markers were found in Er:YAG biopsies, on the
contrary the apoptosis marker was better expressed in CO2 laser biopsies. Conclusion: The results suggest
that Er:YAG laser may be routinely used in surgery, because of its minimal damage of the epithelial tissue, its
low inflammatory reaction, its quicker healing process and its lower risk of scarring
Morphology of peri-implant regenerated bone, in sheep's tibia, by means of guided tissue regeneration.
No full textBACKGROUND: No data on the resistance to functional loads of bone regenerated by means of guided tissue regeneration, can be found. In this paper the new-formed bone is analyzed, in cases that see the surgical creation of defects in testing animals. The morphological aspects of perimplant bone, regenerated by means of bone substitutes or not, were evaluated.
METHODS: A coronal defect was created by means of a counter-sink bur. The following step provided for osseointegrated fixtures, with a machined or blasted (TiOblast) surface, to be installed. Some bone defects were filled with Bio-Oss, and covered with resorbable membrane (Vycril), others were left unfilled. The animals were sacrificed after different periods of time (24 and 45 days). Some thick sections (200 microns) underwent then microradiography and were examined with a microscope, under transmitted and polarized light. Other sections, thin (5 microns), were coloured with toluidine blue, Gomori's Stain and Solochrome Cyanine/Congo red.
RESULTS: Data confirm the excellent behaviour of bovine bone and of TiO blasted fixtures. The experimental results bring into evidence that, in cases of Guided Bone Regeneration (GBR) by means of membrane, the use of fixtures with a blasted surface (TiOblast), and of Bio-Oss as bone substitute, made osseointegration easier.
CONCLUSIONS: Results, moreover, suggest that in case of implant surgery with GBR, in order to allow the maturation of regenerated bone, it's healing time must be prolonged
Clinical analysis on efficacy of root-surface conditioning by ethylenediaminetetraacetic acid on surgical treatment of gingival recessions with coronally advanced flap and enamel matrix derivative peptide: A retrospective study
No full textLow-frequency pulsed electromagnetic fields interfere on histochemical markers of bone remodelling during the healing process of bone defects.
No full textlnununohistochernical detection of cel1-cycle associated markers on paraffin ernbedded and formalin fixed needle biopsies of prostate cancer: correlation of p120 protein expression with AgNOR, PCNA/Cyclin, Ki-67/MIB1 proliferation-scores and Gleason gradings.
No full textParaffin embedded and formalin fixed needle biopsies of prostate cancer (PC) were used to immunocytochemically detect the p120 nucleolar protein in relation to the Gleason histological gradings (GHG), the labelling indices of proliferating nuclear immunocytochemical markers (PCNA/Cyclin, Ki-67/MIB1) and the argyrophilic nucleolar region (AgNOR) rate. The twenty-six cases of PC (6 from large histological samples and 20 from needle biopsies) were equally distributed into low ( or = 7) GHG groups. The p120 nucleolar protein immunocytochemical reaction was randomly expressed in large histological sections but uniformly distributed without gaps in needle biopsy sections. Only on the latter were quantitative values of PCNA/Cyclin (23.2 in low and 45.3 in high GHG), Ki-67/MIB1 (13.8 in low and 43.3 in high GHG) and AgNOR (5.0 in low and 7.5 in high GHG) related to those of p120 nucleolar protein (0.8 in low and 3.8 in high GHG). The values of all these cell cycle markers increased from low to high GHG of PC, all four reaching high statistical significance between the two groups (ANOVA-two tailed p < 0.0001). The PCNA/Cyclin index showed a higher positivity than the Ki-67/MIB1 index in PC with low GHG but not in PC with high GHG. In conclusion, paraffin embedded and formalin fixed PC needle biopsies exhibit a higher diagnostic PCNA/Cyclin than Ki-67/MIB1 index for cases presenting differentiated features, whereas p120 nucleolar protein detection seems to be a suitable marker of poorer outcome of PC
Effects of push-in test on rabbit bone surrounding fixture
No full textThis study highlights that the bone·fixture interfaces resisted to \be axial rolCeS proving Ihat the
OBR with bone grafting allows the fixtures to achieve a high degree ofosscoinlegration
- …
