An implant-supported dental restoration improves quality of life and has a long service life. More and more patients wish to have their dentition restored in this way. Patients who have been treated conventionally also want changes toward better and as aesthetic as possible restorations that resemble the originals down to the smallest detail. The demand for restorations that correspond to the condition before tooth loss, including the shape and position of the soft red tissue, is most often the main cause of complications in the patient–therapist relationship, because those paying for treatment are in fact not interested in how, when and why bone mass was lost in the area where the teeth were extracted. This problem has also led to solutions requiring pre-implant preparation of hard and soft tissues, with the aim of achieving the most optimal possible reconstruction of the dentition.
Atrophy of the alveolar process occurs in areas where it has been without loading. Methods for reconstructing bone ridges were described long before the advent of dental implants. Numerous bone substitutes are known, but autologous grafts still represent the gold standard in reconstruction of the jaws.
Because of high aesthetic demands, reconstruction of the upper alveolar ridge in the visible region is a particular challenge. Loss of the incisors relatively quickly leads to loss of both bone and soft tissue. Reconstruction aims to restore the shape of the vestibular part of the alveolar process together with formation of the jugae alveolariae. Proper reconstruction is also important for adequate support of the upper lip, which is part of a good aesthetic rehabilitation. For decades, clinicians performing reconstructions have regarded the crista zygomaticoalveolaris, because of its convex shape, as an ideal donor site for a graft. In addition to allowing an almost ideal vestibular contour of the reconstructed alveolar ridge, this graft can also achieve a good relationship between hard and soft tissue that does not require additional connective-tissue grafts or additional bone substitutes of non-autologous origin.
In the posterior region, the primary objective is to restore masticatory function with teeth supported by dental implants. In the mandible, favourable implant placement is most often prevented by a reduced vertical bone component above the mandibular nerve, which may also be accompanied by reduced jaw width in the transverse direction. In the maxilla, difficult implant placement is caused by bone loss in the transverse and vertical directions, with relative lowering of the sinus floor also contributing to the problem.
A transverse bone deficiency can be compensated for by bone apposition. The most suitable donor area for this method is the retromolar region. A 3D radiographic image can be of great help in identifying the site of the bone deficiency, facilitating subsequent rehabilitation. So-called sandwich osteoplasty is a method of simultaneously increasing the alveolar ridge vertically and transversely when an increase of no more than approximately 6 mm is required. When more extensive augmentation of the maxillary alveolar ridge is needed in both directions and the vertical bone component to the sinus is reduced below 6 mm, elevation of the sinus floor is required. Authors most often describe a technique involving creation of a window into the sinus. With a bone scraper, the bone thickness should be reduced to a minimum, thereby reducing the possibility of membrane injury when opening the “window”; at the same time, a considerable amount of bone is collected in a prepared cup together with blood, physiological saline and added bone substitute, which increases the volume of the mass to the amount required to fill the space between the sinus floor and the “new floor”, represented by the elevated sinus membrane supported by one of the artificial membranes.
Atrophy of the alveolar process occurs in areas where it has been without loading. Methods for reconstructing bone ridges were described long before the advent of dental implants. Numerous bone substitutes are known, but autologous grafts still represent the gold standard in reconstruction of the jaws.
Because of high aesthetic demands, reconstruction of the upper alveolar ridge in the visible region is a particular challenge. Loss of the incisors relatively quickly leads to loss of both bone and soft tissue. Reconstruction aims to restore the shape of the vestibular part of the alveolar process together with formation of the jugae alveolariae. Proper reconstruction is also important for adequate support of the upper lip, which is part of a good aesthetic rehabilitation. For decades, clinicians performing reconstructions have regarded the crista zygomaticoalveolaris, because of its convex shape, as an ideal donor site for a graft. In addition to allowing an almost ideal vestibular contour of the reconstructed alveolar ridge, this graft can also achieve a good relationship between hard and soft tissue that does not require additional connective-tissue grafts or additional bone substitutes of non-autologous origin.
In the posterior region, the primary objective is to restore masticatory function with teeth supported by dental implants. In the mandible, favourable implant placement is most often prevented by a reduced vertical bone component above the mandibular nerve, which may also be accompanied by reduced jaw width in the transverse direction. In the maxilla, difficult implant placement is caused by bone loss in the transverse and vertical directions, with relative lowering of the sinus floor also contributing to the problem.
A transverse bone deficiency can be compensated for by bone apposition. The most suitable donor area for this method is the retromolar region. A 3D radiographic image can be of great help in identifying the site of the bone deficiency, facilitating subsequent rehabilitation. So-called sandwich osteoplasty is a method of simultaneously increasing the alveolar ridge vertically and transversely when an increase of no more than approximately 6 mm is required. When more extensive augmentation of the maxillary alveolar ridge is needed in both directions and the vertical bone component to the sinus is reduced below 6 mm, elevation of the sinus floor is required. Authors most often describe a technique involving creation of a window into the sinus. With a bone scraper, the bone thickness should be reduced to a minimum, thereby reducing the possibility of membrane injury when opening the “window”; at the same time, a considerable amount of bone is collected in a prepared cup together with blood, physiological saline and added bone substitute, which increases the volume of the mass to the amount required to fill the space between the sinus floor and the “new floor”, represented by the elevated sinus membrane supported by one of the artificial membranes.
