Publications by authors named "Luiz Guilherme Brentegani"

20 Publications

  • Page 1 of 1

Vital Bone Formation After Grafting of Autogenous Bone and Biphasic Calcium Phosphate Bioceramic in Extraction Sockets of Rats: Histological, Histometric, and Immunohistochemical Evaluation.

Implant Dent 2018 Dec;27(6):615-622

Professor, Department of Stomatology, Public Health and Forensic Dentistry, School of Dentistry of Ribeirão Preto, USP-University of São Paulo, Ribeirão Preto, SP, Brazil.

Purpose: The study aimed to investigate through histology, histometry, and immunohistochemistry the vital bone formation after grafting of biphasic calcium phosphate bioceramic (BC) in combination with calvarial autogenous bone into the dental sockets of rats.

Materials And Methods: Forty-five male rats were submitted to upper right incisor extraction and divided according to the grafted material in: control, bioceramic (BC), and bioceramic + autogenous bone (BC + AB). The animals were killed 7, 21, and 42 days after surgery for histological, histometric, and immunohistochemistry analysis.

Results: Histomorphometric results demonstrated, for BC + AB group, formation of trabecular bone between the particles of BCs and autogenous bone, connecting them, as well as higher percentage of vital bone in comparison with BC. Immunohistochemical reactions showed intense labeling for Runx2-positive cells in the group BC + AB.

Conclusions: Autogenous bone was able to stimulate bone turnover enabling a larger amount of vital bone synthesis and can be recommended as a viable grafting material in combination with synthetic biphasic BC.
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http://dx.doi.org/10.1097/ID.0000000000000815DOI Listing
December 2018

Effects of coffee intake and intraperitoneal caffeine on bone repair process--a histologic and histometric study.

Braz Dent J 2015 Mar-Apr;26(2):175-80. Epub 2015 Apr 1.

Public Health and Forensic Dentistry;Department of Stomatology, School of Dentistry of Ribeirão Preto, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.

Studies have suggested that caffeine acts on bone promoting an increase of calcium excretion, inhibition of osteoblast proliferation and delay in tissue repair process, raising the risk of fractures, osteoporosis, periodontal disease and affecting the success of bone reconstructive procedures. The aim of this study was to analyze histomorphometrically the process of alveolar bone healing after tooth extraction in rats subjected to daily intake of boiled coffee or intraperitoneal administration of caffeine. Forty-five male rats were divided according to the treatment in Control group (C); Coffee group (CO) - treated with coffee since birth; and Caffeine (CAF) - intraperitoneal injection of aqueous solution of caffeine 1.5% (0.2 mL/100g body weight) for 30 days. When weighing between 250-300 g they were anesthetized, subjected to extraction of the maxillary right incisor, and euthanized 7, 21 and 42 days after surgery for histological assessments of bone volume and the quality of formed bone in the dental socket. The qualitative results demonstrated larger amounts of blood clot and immature bone in animals under treatment of pure caffeine compared to coffee and control. Histometric analysis revealed that coffee treatment led to a 40% drop in bone formation, and caffeine a 60% drop in comparison to control animals (ANOVA p≤0.01). It was concluded that both the daily ingestion of coffee and the intraperitoneal administration of caffeine in rats delayed the alveolar bone reparative process after tooth extraction, and this effect was more aggressive when pure caffeine was used.
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http://dx.doi.org/10.1590/0103-6440201300219DOI Listing
December 2016

Bone integration behavior of hydroxyapatite/β-tricalcium phosphate graft implanted in dental alveoli: a histomorphometric and scanning electron microscopy study.

Implant Dent 2014 Dec;23(6):710-5

*PhD Student in Oral Rehabilitation, Department of Morphology, Stomatology and Physiology, Ribeirão Preto School of Dentistry, University of São Paulo, São Paulo, Brazil. †Associate Professor, Department of Morphology, Stomatology and Physiology, Ribeirão Preto School of Dentistry, University of São Paulo, São Paulo, Brazil. ‡Associate Professor, Department of Surgery and Anatomy, Ribeirão Preto School of Medicine, University of São Paulo, São Paulo, Brazil. §Professor, Department of Morphology, Stomatology and Physiology, Ribeirão Preto School of Dentistry, University of São Paulo, São Paulo, Brazil.

Purpose: This study investigated the bone integration ability of a biphasic calcium phosphate bioceramic implanted in dental alveolus of rats.

Materials And Methods: A total of 21 male rats were submitted to upper right incisor extraction and implanted with a synthetic bioceramic (Straumann Bone Ceramic). The animals were killed on 7th, 21st, and 42nd day after surgery for light and scanning electron microscopy (SEM) analysis of bone, bioceramic, and soft tissue volume as well as the quality of graft in its interface.

Results: Light histology results showed no persistent inflammatory and foreign body reactions, a newly formed bone adhered on the ceramic surface without interposition of soft tissue, which was confirmed by SEM analysis. Histometrically, reduction/resorption, between 7 and 42 days, in the percentage of bioceramic implanted (α = 1%) left gaps for a gradual increase in vital bone formation (α = 1%) around the particles.

Conclusions: The bioceramic in question is biocompatible, has good bone integration, being gradually resorbed and replaced by it, featuring a viable bone substitute for grafting procedures.
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http://dx.doi.org/10.1097/ID.0000000000000172DOI Listing
December 2014

Mucocele and fibroma: treatment and clinical features for differential diagnosis.

Braz Dent J 2013 Sep-Oct;24(5):537-41

Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão PretoSP, Brazil.

Mucocele is a benign lesion occurring in the buccal mucosa as a result of the rupture of a salivary gland duct and consequent outpouring of mucin into soft tissue. It is usually caused by a local trauma, although in many cases the etiology is uncertain. Mucocele is more commonly found in children and young adults, and the most frequent site is the lower inner portion of the lips. Fibroma, on the other hand, is a benign tumor of fibrous connective tissue that can be considered a reactionary connective tissue hyperplasia in response to trauma and irritation. They usually present hard consistency, are nodular and asymptomatic, with a similar color to the mucosa, sessile base, smooth surface, located in the buccal mucosa along the line of occlusion, tongue and lip mucosa. Conventional treatment for both lesions is conservative surgical excision. Recurrence rate is low for fibroma and high for oral mucoceles. This report presents a series of cases of mucocele and fibroma treated by surgical excision or enucleation and the respective follow-up routine in the dental clinic and discusses the features to be considered in order to distinguish these lesions from each other.
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http://dx.doi.org/10.1590/0103-6440201301838DOI Listing
November 2015

Dental Findings and Management in a Mucopolysaccharidosis Type IIIB Patient.

J Dent Child (Chic) 2012 Sep-Dec;79(3):176-80

School of Dentistry, University of São Paulo at Ribeirão Preto, Brazil.

Mucopolysaccharidosis type IIIB (MPS IIIB) is an autosomal recessive disorder caused by deficiency of the lysosomal enzyme a-N-acetylglucosaminidase. Affected subjects present developmental delay, attention deficit disorder, uncontrollable hyperactivity, and aggressive behavior, followed by progressive dementia and death in late adolescence. The purpose of this paper is to report the dental findings and treatment in a child with MPS IIIB. His primary molars and permanent mandibular incisors presented obliterated pulp chambers and root canals, which may be a clinical manifestation of this disorder.
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August 2013

Eruption sequestrum--case report and histopathological findings.

Braz Dent J 2012 ;23(6):764-7

Department of Pediatric Clinic, Ribeirão Preto Dental School, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.

Eruption sequestrum is an uncommon disturbance in eruption and consists of small fragments of calcified tissue overlying the crowns of erupting permanent molar teeth, especially at the time of eruption of the mandibular first molars. This paper reports a case of unilateral eruption sequestrum in a 7-year-old Brazilian boy and describes its histopathological findings. A white small fragment, 0.5 cm in diameter, with hard consistency, irregular shape and located on the occlusal surface of the erupting mandibular left first molar was excised. Microscopic examination revealed large trabeculae with empty lacunae and a minimal amount of existing spongy bone consisting of acute inflammatory cells (neutrophils). Signs of necrosis were found on the periphery. The histological analysis was consistent with non-vital bone and the diagnosis of eruption sequestrum was established. Clinical and radiographic follow-up visits scheduled at short intervals and then every 6 months revealed normal postoperative conditions.
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http://dx.doi.org/10.1590/s0103-64402012000600023DOI Listing
January 2014

A retrospective study of oral manifestations in patients with paracoccidioidomycosis.

Braz Dent J 2012 ;23(6):753-7

Department of Stomatology, Ribeirão Preto Dental School, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.

South American blastomycosis, paracoccidioidomycosis (Pb mycosis) or Lutz disease is an endemically fungal infection in Latin America. It is caused by the dimorphic fungus Paracoccidioides brasiliensis and may cause oral mucosal lesions. The incidence of Pb mycosis oral lesions was evaluated in patients assisted at a Brazilian Dental School's Specialized Oral Diagnosis Service with special focus on the different clinical forms of these lesions, its location, patients' occupation, deleterious habits, and diagnosis methodology. Students' and professionals' initial diagnoses were compared with the definitive diagnosis. Lesions were detected 31 cases (18 patients). The results show that 88.8% of the patients were male with a mean age of 50 years and 39% work(ed) with activities related to agriculture. As much as 88.9% were smokers and 72.2% were alcohol users. Exfoliative cytology was performed in 66.6% of the patients. Oral mucosa (30%), gingiva (16.6%) and lips 16.6% were the most common sites of Pb mycosis oral lesions. Comparing the initial with the definitive diagnosis made by the professionals their accuracy was 33% (6 out of 18 patients). Students' diagnosis was more accurate demonstrating 72.5% of initial correct diagnosis (13 out of 18). Statistical analysis by ANOVA (α=0.05, SPSS WIN) demonstrated a significant difference between the diagnosis of Pb mycosis made by students and professionals when considering initial diagnosis and final diagnosis (after histopathological analysis) (p=0.25). Incisional biopsy and exfoliate cytology are efficient for an early diagnosis of this disease in mouth. Students' training in diagnosis of oral pathologies to recognize lesions is urgent to improve public health.
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http://dx.doi.org/10.1590/s0103-64402012000600021DOI Listing
January 2014

Osteointegration of autogenous bone graft associated with osteoblastic cells under treatment with caffeine.

Implant Dent 2011 Oct;20(5):369-73

Department of Morphology, Stomatology and Physiology, Dentistry School, University of São Paulo-USP, Ribeirão Preto, São Paulo, Brazil.

Purpose: The present study investigated osteointegration of autogenous bone (AB) from calvaria graft associated with osteoblastic cells (OC) in bone defects in rats subjected to daily administration of caffeine.

Materials And Methods: Male rats received daily intraperitoneal injection of 1.5% caffeine (0.2 mL/100 g body weight) or saline solution for 30 days. Then they were anesthetized, submitted to the extraction of the upper right incisor, and implanted with AB only and AB + OC. The animals were killed on 7th, 21st, and 42nd days after surgery, and their maxilla were processed for obtaining semiserial sections (5 μm) stained with hematoxylin and eosin. Through image analysis system, the bone volume and the quality of graft in adjacent areas were estimated.

Results: The results showed that in caffeine treatment, the AB + OC graft showed no foreign body and acute inflammatory reactions inside the defect when compared to AB. The histometric results revealed that the association AB + OC produced significant increase (10%-15%) in bone volume in later experimental period (42 days) when compared with saline solution group (P ≤ 0.01).

Conclusions: It was concluded that the association of AB from calvaria + OC demonstrated progressive osteointegration and accelerated the repair of bone defects in animals treated with daily caffeine.
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http://dx.doi.org/10.1097/ID.0b013e31822b9b53DOI Listing
October 2011

Bone quality associated with daily intake of coffee: a biochemical, radiographic and histometric study.

Braz Dent J 2010 ;21(3):199-204

Department of Morphology, Stomatology and Physiology, University of São Paulo, Ribeirão Preto, SP, Brazil.

Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-µm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg%) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 %) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.
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http://dx.doi.org/10.1590/s0103-64402010000300004DOI Listing
June 2011

Osteogenic potential of autogenous bone associated with bone marrow osteoblastic cells in bony defects: a histomorphometric study.

Implant Dent 2009 Dec;18(6):521-9

Department of Morphology, Stomatology and Physiology, Dentistry School, University of São Paulo-USP, 14040-904, Ribeirão Preto, São Paulo, Brazil.

Purpose: Because of limitations of autogenous grafts, allografts, xenografts, alloplasts, and hydroxyapatite as graft materials, researchers have been using bone tissue engineering as a strategy for bone regeneration. The aim of this work was to study the effect of bone tissue engineering, associating bone marrow osteoblastic cells, and autogenous bone in defects created by dental extraction in rats.

Materials And Methods: Eighty male rats from 250 to 300 g were anesthetized, submitted to the extraction of the superior incisor, and divided in control group (C), implanted with osteoblastic cells (OC), autogenous bone (AB), and osteoblastic cells + autogenous bone (OC + AB). The animals were killed on 10th and 20th days after surgery and their maxilla were processed for obtaining fine semiserial sections (5 mum), and then stained with hematoxylin-eosin. Through image analysis system, bone volume in areas adjacent to the implants was estimated.

Results: The histometric results revealed that the association OC + AB produced significant increase (10%-15%) of bone in both experimental periods when compared with the control group (P < or = 0.01).

Conclusions: Osteoblastic cells associated with autogenous bone accelerated the repair of bone defect, and the action of the osteoblastic cells was more effective until the 10th day and of the autogenous bone after this period.
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http://dx.doi.org/10.1097/ID.0b013e3181b8e53cDOI Listing
December 2009

Clinical, microscopic and imaging findings associated to McCune-Albright syndrome: report of two cases.

Braz Dent J 2008 ;19(2):165-70

Department of Oral and Maxillofacial Surgery and Traumatology and Periodontics, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.

McCune-Albright syndrome is characterized by the triad café-au-lait cutaneous spots, polyostotic fibrous dysplasia and endocrinopathies. This article presents two cases of McCune-Albright syndrome in a middle-aged woman and a young girl. Both patients presented café-au-lait spots on the face and other parts of the body and expansion of the mandible with radiopaque-radiolucent areas with ground-glass radiographic appearance, and were diagnosed as having fibrous dysplasia and endocrine disorders. The patient of Case 1 had fibrous dysplasia on the upper and lower limbs, thorax, face and cranium, early puberty, hyperglycemia, hyperthyroidism and high serum alkaline phosphatase levels. The patient of Case 2 presented lesions on the upper limbs and evident endocrine disorders. In both cases presented in this article, the initial exam was made because of the mandibular lesion. However, a diagnosis of fibrous dysplasia must lead to investigation of the involvement of other bones, characterizing polyostotic fibrous dysplasia, which is manifested in a number of diseases. An accurate differential diagnosis is mandatory to determine the best treatment approach for each case.
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http://dx.doi.org/10.1590/s0103-64402008000200014DOI Listing
March 2009

Trigeminal nitric oxide synthase expression correlates with new bone formation during distraction osteogenesis.

Calcif Tissue Int 2008 Apr 12;82(4):309-15. Epub 2008 Mar 12.

Faculty of Dentistry of Ribeirão Preto, University of São Paulo, Av. Café S/N, CEP 14040-904, Ribeirão Preto, São Paulo, Brazil.

Nitric oxide synthase (NOS) has been reported to be involved with both bone healing and bone metabolism. The aim of this study was to test the null hypothesis that there is no correlation between new bone formation during mandibular distraction osteogenesis and NOS expression in the trigeminal ganglion of rats. Newly formed tissue during distraction osteogenesis and trigeminal NOS expression measured by the NADPH-diaphorase (NADPH-d) reaction were evaluated in 72 male Wistar rats by histomorphometric and histochemical methods. In animals submitted to 0.5 mm/day distraction osteogenesis, the percentage of bone tissue was higher in the basal area of the mandibles compared with the center and significantly increased through the experimental periods (P < 0.05). At the sixth postoperative week, the difference in bone formation between the continuous and acute distraction osteogenesis groups was the highest. Significant correlation between new bone formation by distraction osteogenesis and NADPH-d-reactive neurons was found, varying according to neuronal cell size (r = -0.6, P = 0.005, small cells strongly stained; r = 0.5, P = 0.018, large cells moderately stained). The results suggest that NOS may play a role in the bone healing process via neurogenic pathways, and the phenomenon seems to be neuronal cell morphotype-dependent. Further studies are now warranted to investigate the mechanistic link between the expression of trigeminal NOS and mandibular new bone formation by distraction osteogenesis.
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http://dx.doi.org/10.1007/s00223-008-9107-8DOI Listing
April 2008

Autogenous bone graft associated with enamel matrix proteins in bone repair.

Implant Dent 2007 Dec;16(4):413-20

Department of Morphology, Stomatology and Physiology, Dentistry School, University of São Paulo-USP, Ribeirão Preto, Sao Paulo, Brazil.

Purpose: Autogenous bone has been used with success as implants in intrabony defects, because of its biological advantages and osteogenic potential. The objective of this study was to evaluate histological and histometrically the bony repair in intrabony defects after dental extractions in rats with graft of a combination of the enamel matrix protein (EMP) (Emdogain, Strauman USA, LLC, Andover, MA. Headquarters in Basel, Switzerland) and autogenous bone.

Materials And Methods: Male rats (Rattus norvegicus, Wistar variety) weighing from 250 to 300 g were anesthetized and submitted to the extraction of the superior incisive and divided in (a) group with autogenous bone (fragment of bone of the alveolar ridge was grafted inside the alveolus) and (b) group with autogenous bone associated with EMP. The animals were killed on the 7th, 21st, and 42nd day after the extraction. The maxillae were processed to obtain fine sections (5 microm) stained with hematoxylin-eosin. The percentual volume of bone tissue in contiguous areas of the graft was calculated through a counting point system of image.

Results: The results showed that the bone fragments grafted in the cervical third of the alveolus developed a progressive osseointegration without foreign-body reaction. The quantification of the bony repair in the areas adjacent to the graft showed that the autogenous bone associated with EMP produced a greater amount of bone (10%-15% by analysis of variance, P = 0.05) in all the studied periods.

Conclusions: It was concluded that the autogenous bone associated with EMP grafted in bony defects, immediately after the dental extraction in rats, demonstrated biocompatibility and accelerated the repair of bone defect.
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http://dx.doi.org/10.1097/ID.0b013e31815705a5DOI Listing
December 2007

Grafting of tooth extraction socket with inorganic bovine bone or bioactive glass particles: comparative histometric study in rats.

Implant Dent 2007 Sep;16(3):260-9

Post-Graduate in Oral Rehabilitation, Dental School of Ribeirão Preto-USP, Brazil.

Purpose: To compare histometrically, in rats, the bone healing after grafting the incisor extraction sockets with inorganic bovine bone or bioactive glass particles.

Material: The volume fraction of grafted materials and alveolar healing components was estimated in histologic images at the end of the second and ninth weeks postoperatively by a differential point-counting method.

Results: Both materials were histologically observed partially filling the cervical alveolar third and, although evoking neither a foreign body reaction nor a persisting inflammatory response, delayed new bone formation in trial areas around their particles. By the second week, the delay in bone healing was more pronounced in the animals grafted with inorganic than in those grafted with bioactive glass, and an opposing result was observed during a 9-week period.

Conclusion: Both inorganic bovine bone and bioactive glass particles grafted in the incisor extraction sockets of rats delayed new bone formation, and the degree of impairment resulted from a combination of factors such as type of material and phase of the reparation process.
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http://dx.doi.org/10.1097/ID.0b013e3180500b95DOI Listing
September 2007

Alveolar wound healing after implantation with a pool of commercially available bovine bone morphogenetic proteins (BMPs): a histometric study in rats.

Braz Dent J 2007 ;18(1):29-33

Department of Morphology, Stomatology and Physiology, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.

The capacity of a commercially available pool of bovine bone morphogenetic proteins (BMPs) to stimulate osteogenesis in the rat alveolar healing was investigated by histometric analysis. Male rats were anesthetized and had their upper incisor extracted. A pool of purified bovine BMPs adsorbed to microgranular resorbable hydroxyapatite was agglutinated with bovine collagen and saline before implantation into the alveolar socket. The implanted and control rats (n=30 per group) were sacrificed 1 to 9 weeks postoperatively, the hemi-maxillae were decalcified, processed for paraffin embedding and semi-serial longitudinal sections were obtained and stained with hematoxylin and eosin. The volume fraction of alveolar healing components was estimated by a differential point-counting method in histologic images. The results showed that in both, control and implanted rats, the alveolar healing followed the histologic pattern usually described in the literature. Quantitative data confirmed that the BMPs mixture did not stimulate new bone formation in the alveolar socket of implanted rats. These results suggest that the pool of BMPs adsorbed to hydroxyapatite and agglutinated with bovine collagen did not warrant incorporation of the osteoinductive proteins to a slow-absorption system that would allow a BMPs release rate compatible to that of new bone formation, and thus more adequate to osteoinduction.
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http://dx.doi.org/10.1590/s0103-64402007000100007DOI Listing
October 2007

Intraosseous schwannoma of mandibular symphysis: case report.

Braz Dent J 2006 ;17(3):255-8

Department of Morphology, Stomatology and Physiology, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.

Schwannoma (neurilemmoma) is a benign neoplasm originated from the neural sheath and occurring most frequently in the head and neck. Intraosseous schwannomas are rare. The mandible is the most common site of occurrence for these lesions. This article reports the case of an intraosseous schwannoma located in the mandibular symphysis of an 11-year-old boy. The lesion was surgically removed and no radiographic evidence of recurrence was observed after 5 years.
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http://dx.doi.org/10.1590/s0103-64402006000300015DOI Listing
March 2007

Use of enamel matrix protein derivative before dental reimplantation: a histometric analysis.

Implant Dent 2005 Sep;14(3):267-73

University of São Paulo-School of Dentistry of Ribeirão Preto-USP, Av. do Café, s/n 14040-904 Ribeirão Preto, São Paulo, Brazil.

The use of enamel matrix protein in the treatment of periodontal defects has shown a favorable action on the proliferation of periodontal ligament cells, as well as on collagen formation and mineralization. The goal was to evaluate, histologically and histometrically, periodontal tissue regeneration after dental reimplantation using enamel matrix protein derivative (Emdogain, Biora AB, Malmö, Sweden). Male rats (Albinus, Wistar), weighing between 180 and 200 g, were divided in 3 groups. Animals in group I (control) had the upper right incisors extracted, the root canal was sealed with calcium hydroxide, and teeth were reimplanted in their alveoli. Group II underwent the same procedure, but the remaining periodontal ligament was removed from the root surfaces by root planing before reimplantation. In group III,following removal of the periodontal ligament, Emdogain was applied to the root surfaces. Animals were sacrificed 7, 20, and 60 days after reimplantation, and the alveoli were fixed, processed, and stained with hematoxylin and eosin. Formation of periodontal ligament, resorption areas, and ankylosis were analyzed. The results showed that group I (control) was better than groups II and III, with statistically significant differences on days 7 and 20 after reimplantation for formation of periodontal ligament. It may be concluded that with the methodology used, Emdogain was unable to stimulate tissue repair in reimplanted teeth.
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http://dx.doi.org/10.1097/01.id.0000173635.94877.35DOI Listing
September 2005

Alcohol intake and osseointegration around implants: a histometric and scanning electron microscopy study.

Implant Dent 2004 Sep;13(3):238-44

Histology Department, Dentistry School of University of São Paulo-USP, Brazil.

Alveolar wound healing can be modified by local and systemic factors. The aim of this study was to evaluate the possible effect of alcoholic beverage administration (sugarcane brandy) on reparative bone formation around hydroxyapatite/tricalcium phosphate implants inside the alveolar socket. Male Wistar rats had their upper right incisors extracted and the bioceramic granules implanted in the alveoli. The animals received increasing concentrations of brandy until 30 degrees Gay-Lussac was achieved starting 30 days before dental extraction and maintained for periods varying from 1 hour to 6 weeks, until sacrifice. Blood alcohol concentration analysis was performed as well as histological and histometric analysis through light and scanning electron microscopy to examine the relation between alveolar healing components, including new bone trabeculae, and the implants. Blood alcohol concentration was significantly higher in treated animals compared with controls. A significant delay in reparative bone formation was detected in the alveolus of alcoholic rats by a histometric differential point counting method, whereas the presence of the bioceramic in the alveolar socket improved alveolar wound healing in alcohol-treated rats. It is suggested that the osteoconductive properties of this bioceramic accelerated alveolar wound healing in alcoholic rats.
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http://dx.doi.org/10.1097/01.id.0000136918.05763.78DOI Listing
September 2004

Bone healing in osteoporotic female rats following intra-alveolar grafting of bioactive glass.

Arch Oral Biol 2004 Sep;49(9):755-62

Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirão Preto-USP, Av. do Café s/n, SP, CEP 14090-904, Brazil.

We have investigated the effect of ovariectomy combined with a low Ca diet on bone healing following the implantation of bioactive glass into extraction sockets, in rats. Ovariectomized rats received a low Ca diet from the day of surgery until sacrifice while sham-operated animals were fed a standard laboratory chow. Two weeks after surgery the upper incisors were extracted and the alveolar sockets in both groups were partially filled with a particulate bioglass (PerioGlas). The animals were killed 1, 2, 3 and 9 weeks after tooth extraction and the relative volume fraction of the healing components (bone trabeculae, connective tissue and coagulum remnants) was estimated in histological paraffin sections by a histometric differential point-counting method. The bioglass particles persisted inside the socket for all the experimental periods and, as bone repair proceeded, they were progressively enclosed in newly formed bone trabeculae which in some cases established a close contact with their surface. The volume fraction of neoformed bone trabeculae relative to the volume fraction of connective tissue and coagulum remnants was greater in the sockets of ovariectomized animals implanted with bioglass than in those of the overiectomized non-implanted groups.
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http://dx.doi.org/10.1016/j.archoralbio.2004.02.013DOI Listing
September 2004

Histometric study of socket healing after tooth extraction in rats treated with diclofenac.

Braz Dent J 2002 ;13(2):92-6

Department of Morphology, Stomatology and Physiology, Faculty of Dentistry of Ribeirão Preto, University of São Paulo, Brazil.

The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.
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http://dx.doi.org/10.1590/s0103-64402002000200003DOI Listing
January 2003