Bone healing in critical-size defects treated with either bone graft, membrane, or a combination of both materials: a histological and histometric study in rat tibiae

Objectives: The aim of the present investigation was to histologically analyze the effect of using lyophilized bovine bone (GenOx (R) organic matrix) with (or without) guided tissue regeneration (using a decalcified cortical osseous membrane [GenDerm (R)]) on bone healing in surgically created critical-size defects created in rat tibia.Material and methods: Surgical critical-size bone defects were created in 64 animals that were randomly divided into four groups: group I (control); group II (defect filled with GenOx (R)); group III (defect covered by GenDerm (R)); group IV (defect filled with GenOx (R) and covered by GenDerm (R)). Animals were killed at 30 or 90 days post-surgery. The specimens were embedded in paraffin, serially cut, and stained with hematoxylin and eosin for analysis under light microscopy. The formation of new bone in the cortical area of the defect was histomorphometrically evaluated.Results: All experimental groups demonstrated superior bone healing compared with the control group. However, group IV samples showed evidence of more advanced healing at both 30 and 90 days post-surgery as compared with the other experimental groups.Conclusions: The bovine organic bone graft GenOx (R) associated with GenDerm (R) this produced the best treatment results in the case of critical-size defects in rat tibia.

Histologic evaluation of the use of membrane, bone graft, and MTA in apical surgery

The aim of this study was to evaluate the periapical healing after the use of membrane, bone graft, and mineral trioxide aggregate (MTA) in apical surgery of dogs' teeth. Apical lesions were induced in 48 roots of 6 dogs after coronal access and pulpal removal. Apical surgery consisted of osteotomy with trephine bur for the standardization of the critical surgical cavities, followed by apicoectomy, curettage, preparation of the root-end cavities with the aid of the ultrasonic device, and retrofilling with MTA. The surgical sites were divided into: group 1-filled with blood; group 2-filled with blood and recovered with membrane; group 3-filled with bone graft; and group 4-filled with bone graft and recovered with membrane. The results showed that the inflammatory infiltrate, the periapical healing process, and the behavior of MTA was the same in all groups, including the mineralization stimulation. It was concluded that the use of membranes and bone graft materials isolated or associated in apical surgery did not alter the periapical healing process after the root-end filling with MTA. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: 309-314)

VEGF and MVD expression in sinus augmentation with autologous bone and several graft materials

The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential.Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer (n = 5 patients) and control group - autogenous bone only (n = 13 patients).In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA (P < 0.001) and CP in relation to control (P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups (P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP (P < 0.001).Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized.

Evaluation of Patients' Perceptions of Alterations After Chin Bone Graft Harvesting

Objective: To evaluate patients' perceptions of alterations occurring after chin bone harvesting.Materials and Methods: Thirty patients were evaluated subjectively by visual analog scale-related sensitivity, facial aesthetics, eating, speaking, and lower lip movement, during 12 months. Objective analysis used the static light touch neurosensorial test. The statistical analysis was executed with Friedman test with P < 0.05 for both samples.Results: Subjective analysis revealed no alterations (1) to facial aesthetics, eating, speaking or lower lip movement but sensitivity of the mental region went from a lot of alteration initially (5) to little at the end of the study (3). Objective analysis results showed normal sensitivity (1) in the region after 12 months.Conclusion: The discrepancy between subjective and objective analyses may be indicative of the limited precision of clinical testing for subjective impressions assessment. (Implant Dent 2012;21:411-414)

Prospective study of soft tissue contour changes following chin bone graft harvesting

This study sought to evaluate changes in the soft tissue contour after chin bone graft harvesting. Thirty selected patients underwent chin bone graft harvesting and evaluations were made using lateral cephalograms preoperatively and postoperatively at 30 and 180 days. Fixed points and lines were established on cephalometric tracings and used to measure the selected vertical and sagittal parameters. Results showed statistically significant alterations to the vertical position values of the vermilion (V-VPV) which increased from 9.70 to 11.01 and the exposure of lower incisors (V-ELI) which increased from 1.85 to 3.5, showing an increase in their distance from the plane of reference and a lowering of their position, the clinical equivalent of a labial ptosis condition. None of the sagittal parameters analysed showed any statistically significant variation in the final evaluation. The study concluded that the alterations to patients' soft tissue contours resulted mainly from failure to ensure precise reattachment of the mentalis muscles and identified the need for further investigation of that aspect.

Tunnel technique with a surgical maneuver to increase the graft extension: Case report with a 3-year follow-up

Background: This article reports a clinical case with a 3-year follow-up in which a subepithelial connective tissue graft (SCTG) was used with the tunnel technique to treat multiple gingival recessions, and describes a technique used to enlarge the extension of the graft.Methods: A 41 -year-old female patient was referred for evaluation and treatment of maxillary multiple recessions. Following basic therapy, the plaque index was 23%, and the gingival index was 12%. Thus, SCTG with the tunnel technique was proposed to provide root coverage of Miller Class I recession on teeth #8 through #11 and a Miller Class III recession on tooth #12. After the donor area had been prepared, SCTG was removed and split cross-sectionally to lengthen it. The graft was placed through the tunnel and sutured.Results: Two weeks after the surgical procedure, the tissue color was nearly homogeneous with some reddish regions where the connective tissue was left uncovered, and there were no signs of incisions or suture marks. After 3 years of follow-up, the mean coverage of the recessions was 2.2 +/- 0.7 mm (74.2%), which corresponded to the gain of keratinized tissue. In addition, a gain in tissue thickness was observed.Conclusion: In a long-term evaluation, the tunnel technique with the elongated SCTG was used successfully for treatment of multiple gingival recessions with an increase of the soft tissue volume and gain of keratinized tissue.

Use of bovine bone graft and bone membrane in defects surgically created in the cranial vault of rabbits. Histologic comparative analysis

Purpose: This study was proposed to analyze histologically the process of repairing bone defects created surgically in the cranial vaults of rabbits. Materials and Methods: Thirty adult male rabbits (Oryctolagus cunilicus) received, under general anesthesia, bilateral parietal osteotomies by means of a 6mm-diameter trephine. The bony defects were divided into 4 groups. In group 1 the defect did not receive any treatment; in group 2 the defect was filled with lyophilized bovine bone (Biograft); in group 3 it was filled with bovine bone and covered with a bone matrix membrane (Bioplate); in group 4 it was covered with a bone matrix membrane. Animals were sacrificed in 3 equal groups at 15, 30, and 60 days. The specimens were subjected to routine laboratory procedures to evaluate the degree of bone repair. Results: After 60 days, new bone formation in group 2 was not satisfactory when compared to that of group 3. Large amounts of new bone formation in maturation were seen in group 3. In the defects covered with a membrane the results were similar to those of group 1 (ie, the cavity was filled with fibrous connective tissue). The implanted bone and membranes were totally resorbed. Discussion and Conclusions: the use of a membrane served as a barrier against the migration of cells from the adjacent tissue and the bone graft/membrane preserved the cavity space, resulting in an enhanced osteogenic effect.

Inside-out vein graft and inside-out artery graft in rat sciatic nerve repair

Although veins and arteries present similar wall structures, there are differences which may be relevant in peripheral nerve reconstruction. Inside-out vein grafts (IOVG) have been satisfactorily used to repair both motor and sensitive nerves. However, the inside-out artery graft (IOAG) is a new technique and not fully investigated. Our study presents comparative morphological data on nerve regeneration achieved with IOVG and IOAG in the repair of Wistar rat sciatic nerves. Jugular veins and aorta arteries were harvested from donor animals and used inside-out to bridge a 10-mm gap. Animals were sacrificed at 10 weeks to evaluate nerve regeneration. Both techniques presented great variability in nervous tissue, though some animals showed satisfactory results. Different intensities of scarring processes might have interfered with nerve regeneration. Although IOVG and IOAG techniques showed similar morphometric results, in general, IOVG presented a closer-to-normal nerve organization than IOAG.

Respiratory pressures and expiratory peak flow rate of patients undergoing coronary artery bypass graft surgery

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Maximum entropy, fractal dimension and lacunarity in quantification of cellular rejection in myocardial biopsy of patients submitted to heart transplantation

This paper presents a method for the quantification of cellular rejection in endomyocardial biopsies of patients submitted to heart transplant. The model is based on automatic multilevel thresholding, which employs histogram quantification techniques, histogram slope percentage analysis and the calculation of maximum entropy. The structures were quantified with the aid of the multi-scale fractal dimension and lacunarity for the identification of behavior patterns in myocardial cellular rejection in order to determine the most adequate treatment for each case.

Homomorphic self-incompatibility, with stylar rejection site, in Luehea grandiflora Mart. and Zucc. (Tiliaceae-Malvaceae s.l.)

The breeding system of Luehea grandiflora (Tiliaceae-Malvaceae s.l.) was investigated using hand pollinations and fluorescence microscopy studies of pollen tube growth. Although selfed flowers persisted for some 10 days, our study indicates that L. grandiflora is self-incompatible, with self pollen tube inhibition in the upper style, as occurs in many taxa with homomorphic, gametophytic self-incompatibility (GSI). L. grandiflora is only the second species reported within the Malvales with homomorphic stylar inhibition. This result is discussed within the context of a report for self-compatibility in this species, and we also consider the phylogenetic implications for the occurrence of GSI in the family Malvaceae s.l.

Fresh-frozen human bone graft for repair of defect after adenomatoid odontogenic tumour removal

The aim of this paper was report the clinical, radiographic, and histological case of adenomatoid odontogenic tumour (AOT) in adolescent woman as well as present the reconstructive treatment of AOT using fresh-frozen human bone graft with guided bone regeneration. AOT is a benign, noninvasive lesion with slow but progressive growth. Biopsy and microscopic examination confirmed the presence of an AOT. Treatment was conservative and the prognosis was excellent. The patient has been followed-up for without recurrence. The use of fresh-frozen human bone graft can be a safe choice for reconstruction of the bone defects to treat AOT.

Influence of Osteopenia in Autogenous Bone Graft Healing With or Without Expanded Polytetrafluoroethylene Membranes: Histologic and Histomorphometric Study in Rats

Purpose: The aim of this study was to quantitatively evaluate and qualitatively describe autogenous bone graft healing with or without an expanded polytetrafluoroethylene (e-PTFE) membrane in ovariectornized rats. Materials and Methods: Eighty Wistar rats, weighing approximately 300 g each, were used. A graft was obtained from the parietal bone and fixed to the sidewall of each animal's left mandibular ramus. The animals were randomly divided into four experimental groups (n = 20 in each group): group 1, sham operated and autogenous bone graft only- group 2, sham operated and autogenous bone graft covered by e-PTFE membrane; group 3, ovariectornized (OVX) and autogenous bone graft only- group 4, OVX and autogenous bone graft covered by e-PTFE membrane. The animals were sacrificed at five different time points: immediately after grafting or at 7, 21, 45, or 60 days after grafting. Histologic examination and morphometric measurement of the sections were performed, and values were submitted to statistical analyses. Results: Both groups (sham and OVX) experienced loss of the original graft volume when it was not covered by the membrane, whereas use of the membrane resulted in additional bone formation beyond the edges of the graft and under the membrane. Histologic analysis showed integration of the grafts in all animals, although a larger number of marrow spaces was found in OVX groups. Conclusions: Association of bone graft with an e-PTFE membrane resulted in maintenance of its original volume as well as formation of new bone that filled the space under the membrane. Osteopenia did not influence bone graft repair, regardless of whether or not it was associated with e-PTFE membrane, but descriptive histologic analysis showed larger numbers of marrow spaces in the bone graft and receptor bed and formation of new bone in the OVX animals. INT J ORAL MAXILLOFAC IMPLANTS 2009;24:1074-1082

Oroantral communication closure using a pedicled buccal fat pad graft

OBJETIVO: O objetivo desde artigo foi relatar um caso clínico de fechamento de fístula buco-sinusal tardia utilizando rotação de enxerto de tecido adiposo pediculado do corpo adiposo da bochecha. DESCRIÇÃO do CASO: Paciente do sexo masculino, 66 anos, leucoderma, em boas condições de saúde geral, foi encaminhado para fechamento de extensa comunicação buco-sinusal. Ao exame clínico, observou-se uma fístula de aproximadamente 10 mm de diâmetro comunicando a cavidade oral com o seio maxilar. A cirurgia foi realizada em nível ambulatorial, sob anestesia local, para fechar a fístula buco-sinusal com um enxerto de tecido adiposo pediculado do corpo adiposo da bochecha. A reparação da ferida e o fechamento do defeito foram observados no pós-operatório de 30 dias, com completa epitelização. CONCLUSÃO: O enxerto pediculado de tecido do corpo adiposo da bochecha mostrou-se uma alternativa simples, eficaz e segura no fechamento mediato da fístula buco-sinusal apresentada neste caso clínico.

Natural latex graft in lamellar and penetrating sclerectomies in rabbits

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