Guide bone substitute materials
Bone substitutes are nowadays a reliable and safe alternative to autologous bone grafts for many indications and are also available in unlimited quantities. Depending on the clinical situation, factors such as indication, age, hygiene, biotype, bone height and treatment plan require a sophisticated approach with coordinated products. Each type of bone substitute features different properties that can be used as an advantage to optimally meet the clinical situation as well as the clinician’s and patient’s requirements. For instance, xenografts, such as cerabone® and cerabone® plus, offer the advantage of long-term volume stability, whereby allografts (e.g. maxgraft®) promote fast natural remodeling into patients’ own bone. Vice versa, synthetic bone substitutes (e.g. maxresorb®) offer a similar success rate and are suitable alternative for patients who refuse the use of allografts or xenografts, e.g. due to religious beliefs or dietary habits.
Xenografts (e.g. cerabone® and cerabone® plus) offer a long-term volume stability compared to allografts and synthetic bone grafts, due to their osseous integration with only superficial resorption. Thus, when the point of implantation is unknown or if a conventional restoration is planned, the use of slow resorbable grafting material is recommended. Additionally, in the anterior region where the bony support of the soft tissue is essential to achieve optimal aesthetic results, the long-term stability of xenografts is advantageous to achieve long-term aesthetic outcomes.
For those who prefer to work with synthetic materials, the biphasic calcium phosphate maxresorb® offers a valid alternative, promoting fast formation of new vital bone, and ensures a controlled resorption without volume loss of the augmented site.
Allografts such as maxgraft® granules, offer the possibility of a faster regeneration, allowing a re-entry after 3-4 months (e.g. socket preservation) and exert high biological regenerative capacity and complete remodeling into vital bone.
Generally, small granules give better surface contouring, especially in the aesthetic region. Those are also particularly favorable when used to fill remaining gaps when working with bone blocks. Furthermore, small particles are preferred for the regeneration of smaller defects and intraosseous defects. On the contrary, large particles are especially useful when more extended defects (i.e. sinus lift) are treated. In addition to the higher volume, the increased space between the particles enables a better revascularization and improves the regeneration process.
Except for cerabone® plus, which requires hydration due to the contained hyaluronate, the botiss bone substitute materials can be applied both dry or wet, therefore rehydration prior application is not mandatory. However, following hydration the particles stick together facilitating their application to the defect site.
Regardless of the type of bone substitute material used, the application of a membrane and the complete coverage of it is important in order to immobilize the particles, minimize micromovements and prevent soft tissue ingrowth into the bone defect. When treating defects outside the ridge contour, a fixation of the membrane by pins or screws can be advantageous. Tension-free wound closure is of utmost importance for the success of the treatment, as it helps to significantly reduce the risk of complications such as dehiscence. Overlapping mobilization of the soft tissue before suturing should be possible.
Each type of bone substitute exerts different features which can be used as an advantage to match the clinical situation, as well the requirements of both the clinician and the patient. Mixing of the botiss bone substitute materials with autologous bone chips is not required but possible. For instance, mixing cerabone® with autologous bone adds a biological activity (osteoinductive and osteogenetic properties of autologous bone) and supports faster regeneration. If harvesting of autologous chips is not possible or desired, the biological potential of maxgraft® and the long-term stability of cerabone® may be combined. The various combinations have been proven successful in different surgical approaches, such as the Sandwich technique and Khoury technique.
Generally, after procedures performed with cerabone® and cerabone® plus a healing time of at least 6 months is recommended before re-entry to ensure stable integration of the particles. Although clinical results demonstrate a somewhat faster regeneration of defects treated with the synthetic maxresorb®, it is recommended to follow the same treatment protocol as for bovine materials. Depending on the defect morphology, the healing time of maxgraft® granules is 3-4 months (e.g. socket preservation, smaller bone defects, periodontal defects). In these cases re-entry with implant placement should be performed promptly to prevent bone resorption. On the other hand, if the time point of implantation is unclear, a bridge restoration is planned or long-term volume support is needed a non-resorbable material such as cerabone® or cerabone® plus should be used.