ABSTRACT
@#After tooth extraction, significant absorption occurs in the soft and hard tissues of the alveolar ridge. The goal of alveolar ridge preservation is to maintain the volume and shape of the alveolar ridge's soft and hard tissues as much as possible so as to provide suitable conditions for implant placement. Currently, there are challenges in classifying the socket for alveolar ridge preservation, such as the difficulty in directly guiding the selection of graft materials and clinical procedures and the insufficient space for particle xenograft maintenance, resulting in poor bone regeneration. Plasmatrix is an autologous blood derivative that effectively enhances tissue regeneration. This article introduced the characteristics of soft and hard tissue defects after tooth extraction and the primary applications of plasmatrix for alveolar ridge preservation (liquid plasmatrix, solid plasmatrix membrane/plug, and plasmatrix bone blocks) as well as the proposed methods for the reclassification of sockets for alveolar ridge preservation based on soft and hard tissue defects at the extraction site to facilitate the creation of clinical recommendations. The proposed classifications are as follows: Class I, extraction socket without bone defect, with or without soft tissue defect; Class Ⅱ, extraction socket with bone defect, both sides with bone wall defect less than 50%, with or without soft tissue defect; Class Ⅲ, extraction socket with bone tissue defect, at least one side with bone wall defect greater than 50%, with or without soft tissue defect. For the Class I socket, a solid plasmatrix membrane or plug is inserted, followed by injection of liquid plasmatrix, using a double-layer solid plasmatrix membrane for socket closure; for the ClassⅡ socket, plasmatrix bone blocks are inserted, followed by injection of liquid plasmatrix and secondary solidification, using absorbable collagen membrane and double-layer solid plasmatrix membrane for socket closure; for the ClassⅢ socket, tenting screws are used to maintain height, followed by implantation of plasmatrix bone blocks, injection of liquid plasmatrix and secondary solidification, using absorbable collagen membrane and double-layer solid plasmatrix membrane for socket closure. The aim of this article is to provide comprehensive knowledge of plasmatrix for oral clinicians to serve as a reference to simplify the clinical decision-making process and procedures for alveolar ridge preservation.
ABSTRACT
@#Vertical bone augmentation surgery still faces considerable challenges in clinical practice due to various problems, such as difficulty in restoring the ideal alveolar bone height and biological complications, and because it is highly technically sensitive. Plasmatrix is derived from patients’ own blood, and it can effectively promote the vascularization of the regenerated area, recruit stem cells, and reduce inflammation when used in vertical bone augmentation. Based on studies published worldwide, this article first divides vertical bone augmentation into 3 categories according to the height of the expected alveolar ridge, namely, type Ⅰ, the required vertical bone gain is less than 4 mm; type Ⅱ, the required vertical bone gain is between 4-8 mm; and type Ⅲ, the required vertical bone gain is greater than 8 mm. In the type Ⅰ vertical bone augmentation, the plasmatrix bone block is directly placed in the defect area and covered with the plasmatrix membrane before tension-free suturing; in the type Ⅱ vertical bone augmentation, the plasmatrix bone block should be placed in the defect area and fixed with titanium nails and then covered with an absorbable collagen membrane and plasmatrix membrane with a tension-free suture; in the type Ⅲ vertical bone augmentation, additional active ingredients (such as bone morphogenetic protein, autologous bone, etc.) should be added to the plasmatrix bone block and strong fixation (such as titanium nails) should be used. Absorbable collagen and plasmatrix membranes should be used to cover the surface of the bone block, and the flap should be sutured. According to different types of vertical bone augmentation categories, the above methods optimize the vertical bone augmentation effect. This article aims to provide a reference and guidelines for oral clinicians to fully understand plasmatrix and simplify the classification and operation of vertical bone augmentation.
ABSTRACT
@#Tooth loss is accompanied by alveolar bone absorption or defect, resulting in insufficient bone and soft tissue. In addition to restoring the masticatory function of missing teeth, implant treatment should also needs to restore the contour and shape of the dental arch. Guided bone regeneration is a common means of bone increase. Xenogeneic granular bone substitute materials are widely used in the field of clinical bone augmentation due to their advantages of long degradation time and low immunogenicity, but other problems, such as inconvenient operation and low osteogenic activity, remain. Plasmatrix can effectively improve the effect of oral tissue regeneration and reduce the occurrence of postoperative complications, and its application in oral tissue regeneration is gradually increasing. This article first introduces the main application forms of plasmatrix in horizontal bone augmentation (mainly solid plasmatrix membrane and plasmatrix bone block), and reclassifies horizontal bone defects according to commonly used decision-making schemes in clinical bone augmentation, in other words, whether the implant can be placed in the ideal position and whether there is bone dehiscence after implantation. Type Ⅰ defects refers to the situation where the bone at the implant site can allow the insertion of an implant with ideal size, and there is no bone dehiscence around the implant, but the alveolar bone contour is not ideal; type Ⅱ defects refers to the situation that when an ideal size implant is placed at the implant site determined by the future prosthesis position, there will be bones on three sides of the implant, but there is bone dehiscence in the buccal bone wall (the length of bone dehiscence is less than 50% of the implant length); type Ⅲ defects refers to the situation where the bone volume at the implant site is not enough to for the placement of the ideal size implant at the ideal position, and bone grafting is required to restore the bone volume before the implant placement. The application of plasmatrix in different types of bone defects is then described. In type Ⅰ bone defects, the solid plasmatrix membrane is used instead of the collagen membrane; in type Ⅱ bone defects, the bone defect around the implant is filled by plasmatrix bone block and then covered with collagen membrane and solid plasmatrix membrane; and in type Ⅲ bone defects, plasmatrix bone block is used to replace autogenous bone block to fill the defect area, and titanium screws are used for fixation. The defect is then covered with a collagen membrane and a solid plasmatrix membrane. This article aims to provide oral clinicians with a comprehensive understanding of plasmatrix and simplify the guidelines for bone regeneration operations.
ABSTRACT
Objective@#To study the osteogenic potential of recombinant human bone morphogenetic protein 2 (rhBMP-2) combined with Bio-oss bone substitute in the implant restoration of bone defects in the anterior esthetic region. @*Methods@# Twelve patients who underwent the immediate placement of 20 implants with a bone augmentation procedure using rhBMP-2 and Bio-oss were included in this study. Changes in the height and thickness of the buccal bone over 6 months were measured, and the soft tissue was evaluated using the pink esthetic score (PES) after crown placement. @*Results@# All 20 implants were successfully osseointegrated, and the average increase in bone height was 1.9 mm; different degrees of bone height growth were observed for 17 (85%) implants sites. In one case, there was a severe bone fracture on the buccal side before the operation, resulting in bone plate resorption and decreased alveolar bone height. The bone height did not change significantly in 2 cases. The thickness of the buccal bone plate for all implants was greater than 1 mm. The average thickness was 1.9 mm, and the average PES was 9.8 points. @*Conclusion@# rhBMP-2 combined with Bio-oss bone substitute has a preferable effect on the restoration of bone defects in the anterior esthetic area, and can achieve good aesthetic effect.