The Overt and Hidden Use of Animal-Derived Products in Alternative Methods for Skin Sensitisation: A Systematic Review.

In vitro methods that can replace animal testing in the identification of skin sensitisers are now a reality. However, as cell culture and related techniques usually rely on animal-derived products, these methods may be failing to address the complete replacement of animals in safety assessment. The objective of this study was to identify the animal-derived products that are used as part of in vitro methods for skin sensitisation testing. Thus, a systematic review of 156 articles featuring 83 different in vitro methods was carried out and, from this review, the use of several animal-derived products from different species was identified, with the use of fetal bovine serum being cited in most of the methods (78%). The use of sera from other animals, monoclonal antibodies and animal proteins were also variously mentioned. While non-animal alternatives are available and methods free of animal-derived products are emerging, most of the current methods reported used at least one animal-derived product, which raises ethical and technical concerns. Therefore, to deliver technically and ethically better in vitro methods for the safety assessment of chemicals, more effort should be made to replace products of animal origin in existing methods and to avoid their use in the development of new method protocols.

Maxillary sinus grafting with fresh frozen allograft versus bovine bone mineral: A tomographic and histological study.

We evaluated histologically and tomographically the effects of fresh frozen bone allograft (FFB) or bovine bone mineral (BBM) in maxillary sinus floor augmentations. In total, 30 maxillary sinuses from 30 patients (mean age = 51.17 ± 10.86 years) underwent sinus augmentation. Patients were divided in two test groups (15 sinuses each). The first group was grafted with allograft bone, and the second group received bovine bone mineral. After 6 months, bone samples from each group were collected for histological examination. Implant survival rates were 97.78% (FFB group) and 100% (BBM group) 6 months after functional loading. Median volumetric reductions of 31.2% (11.33-40.56) and 12.22% (9.91-20.59) were observed in the FFB and BBM groups, respectively. Comparisons between the groups for differences in initial and final volumes of bone (p = 0.015) and the rate of resorption (p = 0.009) showed statistically significant differences. The FFB group showed osteoblastic cells in close contact with osteoid matrix, connected through bridges between allograft bone particles and new bone formation. The BBM group showed BBM particles in close contact with new bone, with visible osteoid matrix bridges and osteoblastic cells surrounding it. None showed signs of acute or chronic inflammatory infiltrate. Despite better results with BBM, both FFB and BBM in maxillary sinus augmentation resulted in high percentages of new bone formation, and allowed implant placement with a low rate of failure of osseointegration at a 6-month follow-up.

Evaluation of inorganic bovine bone graft in periodontal defects after third molar surgery.

AIM: This study evaluated the e cacy of inorganic bovine bone graft (IBB) in periodontal defect after mandibular third molar (3M) surgery. METHODS: The authors conducted a split-mouth, prospective, randomized, blinded, placebo-controlled clinical trial involving 20 participants with a mean age of 21.60 ± 6.5 years who had symmetrical bilateral lower 3M randomly assigned to receive IBB or left empty (blooding clot). The clinical variables studied were probing depth and clinical attachment level (CAL) at preoperative and postoperative periods of 10, 30, and 60 days. Radiographic measures included the distance from the alveolar bone crest to the cementoenamel junction and the bone density at 30 and 60 days postsurgical procedure. For statistical analysis, we used the paired t-test at a level of signi cance of 5%. RESULTS: It was observed a reduction in pocket depth and CAL in both groups, but IBB did not provide better results than blooding clot (P > 0.05). On the other hand, IBB group showed an increased in the bone density, and a decrease in the periodontal defect on the distal surface of second molar (2M) after 30 and 60 days of surgery compared to the control group (P < 0.05). CONCLUSION: The use of inorganic bone graft (GenOx) did not enhance the probing depth after 3M removal. Although the radiographic ndings have showed an increase in bone density and a decrease in the periodontal defect on the distal surface of the 2M, we cannot recommend the use of IBB as a treatment for periodontal defect prevention after 3M removal.

Fresh-frozen allografts combined with bovine bone mineral enhance bone formation in sinus augmentation.

We evaluated histologically, histomorphometrically, and tomographically the effects of the association of fresh-frozen bone allograft (FFB) with bovine bone mineral (BBM) in maxillary sinus floor augmentation. In total, 34 maxillary sinuses from 29 patients, with a mean age of 51.32 (±6.44) years, underwent sinus augmentation. Patients were divided into control and test groups (17 sinuses each). The controls were grafted with allograft bone, and the test group received a combination of FFB and BBM at a 2:1 ratio. After 6 months, bone samples were collected for histological and histomorphometric examinations. The implant survival rates were 93.02% (control group) and 100% (test group) at 6 months after functional loading. Median volumetric reductions of 28.32% (17.05-44.05) and 12.62% (5.65-16.87) were observed for the control and test groups, respectively. Statistically significant histomorphometric differences were found between the control and test groups regarding newly formed bone 12.54% (10.50-13.33) vs. 24.42% (17.62-35.92), p < 0.001, total bone 48.34% (39.03-54.42) vs. 61.32% (50.61-64.96), p = 0.007, and connective tissue 51.66% (45.57-60.97) vs. 39.30% (35.03-49.37), p = 0.007. The addition of BBM to allograft bone in maxillary sinus augmentation resulted in higher percentages of new bone formation and total bone, and permitted implant placement with a low rate of osseointegration failure at the 6-month follow-up.