Читать книгу Bone and Soft Tissue Augmentation in Implantology - Группа авторов - Страница 44

Current development in the field of human genetics is providing an increasing amount of information about genetic developmental disorders. For the development of teeth and the periodontal ligament, ectodermal disorders are mainly relevant.¹⁷ In ectodermal dysplasia, disorders occur on multiple structures that develop from the outer cotyledon. In addition to the hair, nails, and skin, the teeth are also affected. Only very few teeth are present (oligodontia or hypodontia) in the first and the second dentition (mostly canines), in combination with some rudimentary teeth (Fig 2-7a to c). In oligodontia, the existing teeth are often microdontic, so that the prosthetic value is limited. Due to the development-related lack of teeth, the alveolar ridge is also underdeveloped in volume (Fig 2-7d), but the existing structures compensate for the missing bone supply with a dense bone quality. When planning a restoration, special attention must be paid to the existing available space and the growth pattern, so that pretreatment often requires many years of cooperation with the attending orthodontist (Fig 2-7e to n).⁶⁴

Fig 2-7a Panoramic view of a 28-year-old female patient with a mild form of ectodermal dysplasia.

Fig 2-7b Clinical situation 12 years after bone grafting and implant restoration in the mandible.

Fig 2-7c Radiologic control 12 years postoperatively.

Fig 2-7d Severe bone atrophy with hypodontia.

Fig 2-7e Typical appearance of a patient with moderate ectodermal dysplasia.

Fig 2-7f Panoramic radiograph revealing the absence of many teeth.

Fig 2-7g Clinical situation of the mandible with hypodontia and severe bone atrophy.

Fig 2-7h Clinical aspect of the maxilla.

Fig 2-7i Absence of a physiologic VDO due to missing occlusal support.

Fig 2-7j The remaining teeth are prepared to support a fixed temporary restoration. In addition, a temporary implant is inserted in the right mandible.

Fig 2-7k A fixed temporary restoration for the correction of the VDO.

Fig 2-7l The temporary restoration offers good lip support, improving the esthetics.

In the very rare autosomal recessive inherited Papillon-Lefèvre syndrome, the periodontal findings show severe periodontitis, leading to early loss of primary teeth usually up to the 4th year of life, and permanent teeth up to the 14th year. This exceptional periodontal disease presents a pronounced atrophy of the alveolar processes, which requires augmentative pretreatment.⁸⁶

Fig 2-7m Multiple bone block augmentation to reconstruct the missing bone.

Fig 2-7n Radiograph control after insertion of the remaining implants in the grafted bone.