Evidencia clínica e histológica de regeneración de tejido blando a partir de una matriz colágena porcina. Reporte de Caso / Histological and clinical evidence of soft tissue regeneration from a porcine collagen matrix. Case Report

RESUMEN: La pérdida de un diente resulta en la pérdida de volumen de tejidos duros y blandos lo que dificulta lograr resultados estéticamente satisfactorios. Con el fin de disminuir la morbilidad que provoca un injerto autólogo en el sellado del alveolo se puede reemplazar por una matriz reabsorbible de colágeno. El presente reporte de caso evaluó clínica e histológicamente una matriz colágena de porcino, en la regeneración de tejido blando, durante la instalación de un implante inmediato a una extracción dentaria. A los 6 meses clínicamente se obtuvo un tejido con una apariencia estética final óptima e histológicamente se evidenció la formación de un tejido epitelial y conjuntivo compatible con la de una mucosa normal.

ABSTRACT: Tooth loss results in loss of hard and soft tissue volume, making it difficult to achieve aesthetically pleasing results. In order to decrease the morbidity caused by an autologous graft in the alveolus seal, it can be replaced by a resorbable matrix of collagen. The present case report evaluated clinically and histologically a porcine collagen matrix, in soft tissue regeneration, during the installation of an implant immediately after dental extraction. At 6 months, clinically, a tissue with an optimal final aesthetic appearance was obtained and histologically, the formation of an epithelial and connective tissue compatible with that of a normal mucosa was evidenced.

Volumetric soft tissue alterations in the early healing phase after peri- implant soft tissue contour augmentation with a porcine collagen matrix versus the autologous connective tissue graft: A controlled clinical trial.

AIM: This study evaluates the early volumetric changes after buccal soft tissue contour augmentation around implants with a porcine collagen matrix (CM) vs. the subepithelial connective tissue graft (SCTG) from the palate. MATERIALS AND METHODS: 14 patients were enrolled after early implant placement with simultaneous contour augmentation and persistent buccal tissue deficits. At implant exposure, buccal soft tissues were thickened with the CM (n = 7) or the SCTG (n = 7). Impressions were taken before and after surgery, after ten days, one, three and six months. Impressions were digitized and augmented regions 3D evaluated (soft tissue volume (mm3 , %)/thickness (mm)). RESULTS: Volume increase (mm3 ) after 6 months was 19.56 ± 8.95 mm3 (CM) and 61.75 ± 52.69 mm3 (SCTG) (insignificant, p = .058). In percentage, this was a volume loss of the initially augmented soft tissue volume (100%) of 81.76% in the CM group and 56.39% in the SCTG group (6 months). The mean soft tissue thickness increase (mm) in the buccal contour after 6 months was 0.30 ± 0.16 mm (CM) and 0.80 ± 0.61 mm (SCTG) (insignificant, p = .071). CONCLUSION: The early healing phase is associated with a significant volume loss of the soft tissues. The SCTG shows insignificant superiority compared to the CM.

Gingiva thickening with a porcine collagen matrix in a preclinical dog model: Histological outcomes.

AIM: To compare 10-month histological and immunohistological outcomes after soft tissue thickening around teeth with a porcine collagen matrix (CM) versus a subepithelial connective tissue graft (SCTG). MATERIAL AND METHODS: In eight beagle dogs, soft tissue thickening of the buccal gingiva of upper canines was performed with the SCTG or the CM. Connective tissue thickness (CTT) was histomorphometrically measured in the augmented regions. The augmented connective tissues were also histologically characterized and the collagen I and vascular endothelial growth factor (VEGF) expressions immunohistologically quantified. RESULTS: CTT significantly differed between groups (SCTG: 1.32 mm ± 0.44 mm; CM: 1.06 mm ± 0.27 mm; p = .008). Descriptive histological analyses revealed mature connective tissue that did not differ between groups. Immunohistological quantification of collagen I and VEGF expressions in the connective tissue also revealed no significant inter-group differences (collagen I: SCTG, 32.64% ± 7.09% vs. CM, 30.57% ± 7.83%; VEGF: SCTG, 39.06% ± 7.27% vs. CM, 37.15% ± 9.80%). CONCLUSION: SCTG is superior to CM with regard to CTT in this experimental model. The CM and the SCTG lead to comparable connective tissue quality ten months after connective tissue thickening.

O uso da matriz colágena porcina na reconstrução tecidual em Periodontia / The use of the porcin collagen matrix in the periodontal tissue reconstruction

A doença periodontal causa uma perda na estrutura de suporte dos elementos dentários. Como consequência, ocorre o aparecimento de sequelas provenientes dessa doença. Por conta disso foram desenvolvidos materiais com a fi nalidade de regeneração tecidual na estrutura de suporte, para que houvesse maior sobrevida desses elementos, aumento na quantidade de gengiva inserida e melhor otimização estética para os pacientes. Dentre os inúmeros materiais, temos a Matriz Colágena Porcina, que simplesmente é uma membrana obtida a partir de suínos, sendo que esta passa por uma cadeia de procedimentos, com a fi nalidade de minimizar e/ou eliminar qualquer tipo de interação alergênica no ser humano. A sua utilização é dada principalmente no aumento de tecidos moles ao redor de dentes afetados com a doença periodontal e em implantes osseointegrados, trazendo como principal vantagem a redução de morbidade do paciente, evitando, assim, a necessidade de um segundo sítio cirúrgico.

Periodontal disease results in the loss of structural support on dental elements. As such, sequels can be seen in the mouth. For this, materials were develop for tissue regeneration in order to increase the amount of attached gingiva and to optimize patient esthetics. The porcine collagen matrix is a product were the collagen undergoes a series of several treatments to minimize any type of allergic reaction to the human body. For example, it can be used for soft tissue augmentation around affected teeth and dental implants. Also, the porcine collagen matrix can reduce patient morbidity because it avoids autologous soft tissue harvesting.

FTIR and SEM analysis applied in tissue engineering for root recovering surgery.

Gingival recession is defined by the displacement of the gingival margin in the apical direction, which overcomes the cementum enamel junction. The etiology of gingival retraction is related to tissue inflammation caused by the accumulation of biofilm, by trauma from brushing action. Aesthetic periodontal surgery aims to return the root coverage to aesthetic harmony, and reduce the risk of periodontal disease and caries. To assist in the root coverage process, the porcine collagen matrix (PCM) has been widely studied. The objectives of this study are to identify the types of collagen that make up the PCM and analyze their morphology. For this, five PCM fragments, 2 mm (thickness) × 2.6 mm (width), were analyzed with the aid of scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The analysis by SEM showed that the PCM consists of two layers; the surface layer is compact, low porosity, and smooth surface, and a foamed underlying layer has high porosity. Through FTIR we identified that the surface and underlying layers are composed of collagen types I and III, respectively. This biomaterial is conducive to root coverage; it allows adsorption and cell proliferation following the matrix resorption and periodontal tissue neoformation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1326-1329, 2017.

Efeitos positivos preliminares de estratégias cirúrgicas e peri-implantares, combinadas para redução dos defeitos alveolares na zona estética provocados após trauma de avulsão, reimplantação dentária e reabsorção radicular / Positive preliminary effects of combined surgical and peri-implant strategies to reduce the alveolar defects at the esthetic zone after avulsion trauma, tooth replantation, and root resorption ­ a case report

Este relato de caso demonstra uma combinação de estratégias de RTG para alívio do defeito residual na zona estética. Um paciente do sexo masculino havia sofrido um acidente traumático no dente 11 durante a infância, com tratamento endodôntico e reimplantação imediata. Dez anos depois, o desnível entre as margens gengivais era de 10 mm, e uma reabsorção radicular estava presente. Para tentar diminuir a recessão de tecido mole e o contorno ósseo deficiente, uma matriz colágena suína (MucoGraft) foi montada no sentido vertical substituindo a parede vestibular, e o alvéolo de extração foi preenchido com osso bovino inorgânico (Bio-Oss). A coroa dentária natural foi usada como pôntico no aparelho ortodôntico de contenção. Três meses depois, e após um exame por tomografia computadorizada feixe cônico para determinação dos níveis ósseos resultantes, o conjunto implante dentário (3,4 mm x 10 mm)/pilar (platformswitching) e osso bovino foi colocado no alvéolo cicatrizado, e a coroa natural foi trocada por uma coroa provisória cimentada. Seis meses depois, um enxerto gengival livre foi aplicado. Após o condicionamento do tecido mole, o desnivelamento gengival entre as margens reduziu-se para 2 mm. A restauração definitiva recebeu infraestrutura em zircônia CAD/CAM recoberta por porcelana feldspática. Mesmo que a estratégia combinada tenha se mostrado útil no alívio da situação clínica, estudos longitudinais com amostras maiores são necessários para comprovar sua eficácia.

This case report demonstrates a combination of RTG strategies to alleviate a residual defect in the esthetic zone. A male patient had suffered a traumatic accident at the tooth 11 during childhood, with endodontic treatment and immediate replantation. Ten years later, the unbalance between the gingival margins was 10 mm, and a root resorption was detected. In an attempt to reduce the soft tissue recession and poor bone contour, a porcine collagen matrix (MucoGraft) was mounted vertically replacing the labial wall, and the alveolar extraction socket fi lled with xenogeneic bovine bone (Bio-Oss). The natural dental crown was used as the pontic in the orthodontic device. Three months later and after a cone beam computerized tomography to determine the resulting bone levels, the dental implant (3.4 mm x 10 mm)/abutment (platform-switching) assembly and bovine bone were placed in the healed socket, and the natural crown was replaced by a cemented temporary crown. Six months later, a free gingival graft was applied. After soft tissue conditioning, the unbalance between gingival margins between was reduced to 2 mm. The final restoration received a CAD/CAM zirconia infrastructure veneered with feldspathic porcelain. Even that the combined strategy has proven useful in this clinical situation. Longitudinal studies with larger samples are needed to confi rm its effectiveness.

Soft tissue volume alterations after connective tissue grafting at teeth: the subepithelial autologous connective tissue graft versus a porcine collagen matrix - a pre-clinical volumetric analysis.

AIM: This study evaluates a porcine collagen matrix (CM) for soft tissue thickening in comparison to the subepithelial connective tissue graft (SCTG). MATERIAL AND METHODS: In eight beagle dogs, soft tissue thickening was performed at the buccal aspects of the upper canines (SCTG and CM). Impressions were taken before augmentation (i1), after surgery (i2), after one (i3), three (i4) and ten month (i5). Casts were optically scanned with a 3D scanner and each augmented region (unit of analysis) evaluated (primary outcome variable: volume increase in mm(3) ; secondary outcome variables: volume increase in percent, mean and maximum thickness increases in mm). RESULTS: 3D tissue measurements after surgery revealed a significant higher volume increase in the CM (86.37 mm(3)  ± 35.16 mm(3) ) than in the SCTG group (47.65 mm(3)  ± 17.90 mm(3) ). After 10 months, volume increase was non-significant between groups (SCTG:11.36 mm(3)  ± 9.26 mm(3) ; CM: 8.67 mm(3)  ± 13.67 mm(3) ). Maximum soft tissue thickness increase (i1-i5) was 0.66 mm ± 0.29 mm (SCTG) and 0.79 mm ± 0.37 mm (CM) with no significant difference. CONCLUSIONS: Ten months after soft tissue thickening, the CM is statistically non-inferior to the SCTG in terms of soft tissue volume and thickness increase. Further 3D studies are needed to confirm the data.

Long-term outcomes after vestibuloplasty with a porcine collagen matrix (Mucograft® ) versus the free gingival graft: a comparative prospective clinical trial.

OBJECTIVES: Porcine collagen matrices are proclaimed being a sufficient alternative to autologous free gingival grafts (FGG) in terms of augmenting the keratinized mucosa. The collagen matrix Mucograft® (CM) already showed a comparable clinical performance in the early healing phase, similar histological appearance, and even a more natural appearance of augmented regions. Predictability for long-term stability does not yet exist due to missing studies reporting of a follow-up >6 months. MATERIAL AND METHODS: The study included 48 patients with atrophic edentulous or partially edentulous lower jaw situations that had undergone an implant treatment. In the context of implant exposure, a vestibuloplasty was either performed with two FGGs from the palate (n = 21 patients) or with the CM (n = 27 patients). Surgery time was recorded from the first incision to the last suture. Follow-up examinations were performed at the following time points: 10, 30, 90, and 180 days and 1, 2, 3, 4, and 5 years after surgery. The width of keratinized mucosa was measured at the buccal aspect of each implant, and augmented sites were evaluated in terms of their clinical appearances (texture and color). RESULTS: The groups showed similar healing with increased peri-implant keratinized mucosa after surgery (FGG: 13.06 mm ± 2.26 mm and CM: 12.96 mm ± 2.86 mm). The maximum follow-up was 5 years (5 patients per group). After 180 days, the width of keratinized mucosa had decreased to 67.08 ± 13.85% in the FGG group and 58.88 ± 14.62% in the CM group with no statistically significant difference. The total loss of the width of keratinized mucosa after 5 years was significant between the FGG (40.65%) and the CM group (52.89%). The CM group had significantly shorter operation times than the FGG group. Augmented soft tissues had a comparable clinical appearance to adjacent native gingiva in the CM group. FGGs could still be defined after 5 years. CONCLUSIONS: The FGG and the CM are both suitable for the regeneration of the peri-implant keratinized mucosa with a sufficient long-term stability. With the CM, tissue harvesting procedures are invalid, surgery time can be reduced, and regenerated tissues have a more esthetic appearance.