Analysis of experimental tendinitis in rats treated with laser and platelet-rich plasma therapies by Raman spectroscopy and histometry

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of Cadmium on the Rat Salivary Glands, During Lactation

Cadmium (Cd) in air, drinking water and food has the potential to affect the health of people, mainly those who live in highly industrialized regions. Cd affects placental function, can cross the placental barrier and directly modify fetal development. Once the organism is particularly susceptible to the exposition to the Cd during the perinatal period, and that this metal can be excreted in the milk, the aim of the present work was to study the effects of the constant exposition to drinkable water containing low levels of Cd during the lactation, on the salivary glands of the rat. Female rats received ad libitum drinking water containing 300mg/l of CdCl2 throughout the whole lactation. Control animals received a similar volume of water without Cd. Lactant rats (21 day old) were killed by lethal dose of anesthetic. The salivary glands were separated, fixed in ""alfac"" solution for 24 h, and serially sectioned. The 6 mu m thick sections were stained with hematoxylin and eosin. Nuclear glandular parameters were estimated, as well as cytoplasm and cell volume, nucleus/cytoplasm ratio, number and surface density, diameters and cell thickness. Mean body weight was 34.86 g for the control group and 18.56 g for the Cd-treated group. Histologically, the glandular acini were significantly smaller, the gland ducts were similar in both groups studied. The connective tissue was more abundant. In conclusion, the salivary glands (submandibular, parotid and sublingual) showed retarded growth after Cd intoxication.

Análise histométrica do desenvolvimento testicular de cutias (Dasyprocta aguti) criadas em cativeiros

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Miniplate fixation for the repair of segmental mandibular defects filled with autogenous bone in cats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Miniplate 1.5 fixation for the repair of mandibular osteotomies in cats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Histometric analysis of ligature-induced periodontitis in rats: a comparison of histological section planes

The purpose of this study was to analyze the histometry of ligature-induced periodontitis in rats at different histological section depths. Sixteen male adult Wistar rats were randomly assigned to two groups: ligature and control. In the ligature group, rats received a sterile 4/0 silk ligature around the maxillary right 2nd molar. Thirty serial sections containing the 1st and 2nd molars, in which the coronal and root pulp, cementoenamel junction (CEJ) in the mesial side of the 2nd molar, interproximal alveolar bone and connective fiber attachment were clearly visible, were selected for histometric analysis. The histological sections were clustered in groups of 10 sections corresponding the buccal (B), central (C) and lingual (L) regions of the of periodontal tissue samples. The distance between the CEJ in the mesial side of the 2nd molar and the attached periodontal ligament fibers (CEJ-PL) as well as the distance between the CEJ and the alveolar bone crest (CEJ-BC) were determined. From CEJ-PL and CEJ-BC distances measured for each specimen, the measurements obtained in the B, L and C regions were recorded individually and together. Data were submitted to statistical analysis. Significant differences (p<0.001) were observed between the control and ligature groups regarding CEJ-PL (0.05 mm and 0.26 mm, respectively) and CEJ-BC (0.47 mm and 0.77 mm, respectively) measurements. Regarding the depth of the buccal, central and lingual planes, the means of CEJ-PL and CEJ-BC of both groups showed no statistically significant differences (p>0.05). In conclusion, the selection of 10 serial sections of the central region of periodontal tissue samples at any depth can be considered as representative for the evaluation of periodontal ligament fiber attachment and bone loss in ligature-induced periodontitis in rats.

Filling of extraction sockets with autogenous bone in cats

OBJETIVO: Avaliar a regeneração óssea de alvéolos dentais de gatos após enxertia. MÉTODOS: Dezoito gatos adultos, distribuídos em três grupos de 6 animais cada, foram submetidos a extração do canino mandibular direito ou esquerdo. No grupo 1, controle, o alvéolo foi deixado vazio. No grupo 2, o alvéolo foi preenchido com osso esponjoso autógeno do osso ilíaco e no grupo 3, com raspa de osso cortical do osso ilíaco. Os animais foram submetidos à eutanásia 6 semanas após a cirurgia. RESULTADOS: Nas radiografias realizadas no pós-operatório imediato na projeção ventrodorsal observou-se uma área de radiolucência correspondente ao local da alveolectomia e extração dentária. Diminuição da radiolucência foi verificada nas radiografias realizadas seis semanas após a cirurgia. Nos cortes histológicos verificou-se a presença de trabéculas ósseas. A porcentagem de tecido ósseo esponjoso presente nos alvéolos dentais foi quantificada por exames histométricos. Não houve diferença estatisticamente significante entre os grupos (Teste de Kruskal-Wallis p > 0.05) (grupo 1: 52,54 ± 15,4; grupo 2: 50,51 ± 5,01; grupo 3: 51,85 ± 9,52). CONCLUSÃO: Os alvéolos dentais de gatos preenchidos com osso esponjoso autógeno ou raspa de osso cortical autógeno apresentaram regeneração óssea similar àquela observada no grupo controle, após um período de observação de seis semanas.

Effect of mismatching abutments on implants with wider platforms - an experimental study in dogs

Aim: To evaluate the effect of mismatching abutments on implants with a wider platform on the peri-implant hard tissue remodeling and the soft tissue dimensions.Material and methods: Mandibular premolars and first molars of six Labrador dogs were extracted bilaterally. After 3 months of healing, one tapered implant was installed on each side of the mandibular molar region with the implant shoulder placed at the level of the buccal alveolar bony crest. on the right side of the mandible, an abutment of reduced diameter in relation to the platform of the implant was used, creating a mismatch of 0.85 mm (test), whereas an abutment of the same diameter of the implant platform was affixed in the left side of the mandible (control). The flaps were sutured to allow a non-submerged healing. After 4 months, the animals were sacrificed and ground sections were obtained for histometric assessment.Results: All implants were completely osseo-integrated. Bone levels were superior at the test than at the control sites. However, statistically significant differences were found only at the buccal and proximal aspects. The soft tissue vertical dimension was higher at the control compared with the test sites. However, statistically significant differences were demonstrated only at the buccal aspects.Conclusions: A mismatch of 0.85 mm between the implant and the abutment yielded more coronal levels of bone-to-implant contact and a reduced height of the peri-implant soft tissue (biologic width), especially at the buccal aspect, if the implant shoulder was placed flush with the level of the buccal alveolar bony crest.

Daily sperm production and testicular morphometry in goats according to external scrotal conformation

The present study aimed to compare testicular histology and the testicular cell population as well as spermatogenic efficiency in goats with different scrotal conformations. Eighteen goats were divided into 3 groups: Group I - goats without bipartition of the scrotum, Group II - animals with bipartition of the scrotum up to 50% of the testicular length, Group III - goats with scrotal bipartition more than 50% of the testicular length. In goats in Groups I, II and III, the values for the volume density of seminiferous epithelium were 68.9 +/- 0.6%, 71.5 +/- 2.8% and 73.4 +/- 4.7% (P < 0.05), the height of the seminiferous epithelium were 60.2 +/- 4.9 mu m, 61.0 +/- 5.0 mu m and 73.1 +/- 6.6 mu m (P < 0.05), total length of seminiferous tubules found for Groups I, II and III were 2091.9 +/- 27 m, 2172.5 +/- 24.1 m, and 2340.1 14 m (P < 0.05), number of Sertoli and Leydig cells were 1.8 +/- 0.4 x 10(9) and 1.4 +/- 0.1 x 10(9), 2.2 +/- 0.4 and 2.2 +/- 0.7 x 10(9), and 2.5 +/- 0.1 10(9) and 2.3 +/- 0.510(9)(P < 0.05)and daily sperm production observed were 2.1 0.3 x 109, 2.8 0.4 x 109, and 3.1 0.7 x 109 (P < 0.05). In conclusion, goats with greater scrotal bipartition have a greater capacity to produce reproductive cells that is reflected in a greater reproductive potential. (C) 2011 Elsevier B.V. All rights reserved.

Influence of various implant platform configurations on peri-implant tissue dimensions: an experimental study in dog

AimTo evaluate the influence (i) of various implant platform configurations and (ii) of implant surface characteristics on peri-implant tissue dimensions in a dog model.Material and methodsMandibular premolars and first molars were extracted bilaterally in six Labrador dogs. After 3 months of healing, two implants, one with a turned and a second with a moderately rough surface, were installed on each side of the mandible in the premolar region. on the right side of the mandible, implants with a tapered and enlarged platform were used, while standard cylindrical implants were installed in the left side of the mandible. Abutments with the diameter of the cylindrical implants were used resulting in a mismatch of 0.25 mm at the tapered implant sites. The flaps were sutured to allow a non-submerged healing. After 4 months, the animals were sacrificed and ground sections were obtained for histometric assessment.ResultsAll implants were completely osseointegrated. A minimal buccal bone resorption was observed for both implant configurations and surface topographies. Considering the animals as the statistical unit, no significant differences were found at the buccal aspect in relation to bone levels and soft tissue dimensions. The surface topographies did not influence the outcomes either.ConclusionsThe present study failed to show differences in peri-implant tissue dimensions when a mismatch of 0.25 mm from a tapered platform to an abutment was applied. The surface topographies influence a neither marginal bone resorption or peri-implant soft tissue dimension.To cite this article:Baffone GM, Botticelli D, Pantani F, Cardoso LC, Schweikert MT, Lang NP. Influence of various implant platform configurations on peri-implant tissue dimensions: an experimental study in dog.Clin. Oral Impl. Res. 22, 2011; 438-444.

Morphological evaluation of combined effects of cyclosporin and nifedipine on gingival overgrowth in rats

It has previously been shown that, while cyclosporin A (CsA) and nifedipine both cause gingival overgrowth in the rat. the combined use of these drugs increases the severity of overgrowth. The aim of this study was to describe the histometry and densities of fibroblasts, collagen fibers and vessels in the gingival tissue of rats that were treated with CsA and nifedipine, either alone or in combination. Rats were treated for 60 days with a daily subcutaneous injection of 10 mg/kg body weight of CsA and/or with 50 mg/kg body weight of nifedipine added to the chow. The results confirmed that CsA causes a more severe overgrowth than nifedipine, and that the combined use of these drugs increases the overgrowth severity. All the rat groups that were studied showed that, as the severity of overgrowth increased, there was a parallel increase in fibroblasts and collagen, and a decrease in vessel content. Therefore, independently of whether the gingival overgrowth was caused by CsA alone, nifedipine alone, or both treatments in combination, the fibroblast and collagen density increased in parallel with the severity of the overgrowth. © Blackwell Munksgaard, 2002.

Cyclosporin but not tacrolimus significantly increases salivary cytokine contents in rats

Background: Cyclosporin (CsA) and tacrolimus (FK-506) are immunosuppressive drugs that specifically inhibit T-cell activation via calcineurin inhibition. Gingival overgrowth is a common side effect following the administration of CsA. The severity of gingival overgrowth seen in patients taking FK-506 is less than that observed with CsA. Little is known about the involvement of saliva in drug-induced gingival overgrowth. The purpose of this study was to investigate the salivary contents of tumor growth factor β1 (TGF-β1), epidermal growth factor (EGF), and interleukin-6 (IL-6) as well as the hystometry of gingival tissue obtained from rats treated with either FK-506 or CsA. Methods: For 30 or 60 days rats received daily subcutaneous injection doses of either CsA or FK-506 (10 mg/kg). The concentrations of TGF-β1, EGF, and IL-6 in saliva were determined by enzyme-linked immunosorbent assay, and after histological processing, the oral epithelium and connective tissue were assessed at the region of the lower first molars. Results: The levels of TGF-β1, EGF, and IL-6 in saliva were not significantly altered by any of the treatments after 30 days. After 60 days of treatment with CsA, gingival overgrowth and significant increase in salivary TGF-β1, EGF, and IL-6 concentrations were observed; no statistically significant changes were induced by FK-506. Conclusion: Within the limits of this experimental study, it can be concluded that CsA, but not FK-506, induced gingival overgrowth associated with an increase of the salivary levels of the cytokines TGF-β1, EGF, and IL-6.

Autogenous bone graft with or without a calcium sulfate barrier in the treatment of class II furcation defects: A histologic and histometric study in dogs

Background: The purpose of this study was to histologically evaluate the healing of surgically created Class II furcation defects treated using an autogenous bone (AB) graft with or without a calcium sulfate (CS) barrier. Methods: The second, third, and fourth mandibular premolars (P2, P3, and P4) of six mongrel dogs were used in this study. Class II furcation defects (5 mm in height × 2 mm in depth) were surgically created and immediately treated. Teeth were randomly divided into three groups: group C (control), in which the defect was filled with blood clot; group AB, in which the defect was filled with AB graft; and group AB/CS, in which the defect was filled with AB graft and covered by a CS barrier. Elaps were repositioned to cover all defects. The animals were euthanized 90 days post-surgery. Mesio-distal serial sections were obtained and stained with either hematoxylin and eosin or Masson's trichrome. Histometric, using image-analysis software, and histologic analyses were performed. Linear and area measurements of periodontal healing were evaluated and calculated as a percentage of the original defect. Percentage data were transformed into arccosine for statistical analysis (analysis of variance; P<0.05). Results: Periodontal regeneration in the three groups was similar. Regeneration of bone and connective tissue in the furcation defects was incomplete in most of the specimens. Statistically significant differences were not found in any of the evaluated parameters among the groups. Conclusion: Periodontal healing was similar using surgical debridement alone, AB graft, or AB graft with a CS barrier in the treatment of Class II furcation defects.