Читать книгу Bone and Soft Tissue Augmentation in Implantology - Группа авторов - Страница 52

The use of periapical radiographs is particularly recommended to obtain clearer detail of the teeth, bone, and implants. This kind of diagnostic technique is especially recommended for the determination of bone loss around implants or teeth and for the detection of caries (Fig 2-14a and b). In case of planning a bone augmentation, especially if using vertical bone augmentation techniques, periapical radiographs are recommended to detect bone structures covering the neighboring teeth. This information is very important, since vertical bone grafting is limited to the bone level of the neighboring teeth.

Fig 2-12a Measurement of mucosal thickness with a thin needle with an attached endo stopper.

Fig 2-12b Transmission of mucosal thickness measurement on a saw-cut model.

Fig 2-13 Important sclerosis close to the basal areas of the edentulous part of the mandible after failure and removal of all implants inserted in grafted bone from the iliac crest. The patient’s history reveals the extraction of several teeth after multiple apicoectomies due to long-term chronic infections.

Fig 2-14a Panoramic radiograph documenting an implant at the area of the central left incisor and some apical reactions on the second premolar and first maxillary left molar. A peri-implant pathology is difficult to detect here.

Fig 2-14b Periapical radiograph documenting a severe peri-implant bone loss and a deep caries on the neighboring lateral incisor. A thin bone layer is still covering the neighboring roots.

Fig 2-14c Determination of the vertical bone dimension with reference balls.

When using traditional periapical radiographs, the parallel technique is metrically more accurate than the half-angle technique.⁷³ The use of a holder system for the parallel technique allows for secure positioning, so that a true-to-size and precise image recording can be achieved. Nevertheless, this may lead to deviations or distortions. Therefore, length determination should be verified by an earlier (already created) panoramic radiograph or CBCT in order to achieve an accurate length determination for implant planning.

Use of the dental status for extensive planning has not proven to be successful because the spatial relationships can only be insufficiently detected and there is the risk of an incorrect assessment of the vertical dimension due to deviations in the projection technique. Limited information regarding bone quality can be determined by a periapical radiograph.

Implant therapy is long term and requires appropriate follow-up assessments to evaluate the individual risk of peri-implantitis. Therefore, in addition to the initial diagnosis for the planning of the surgical procedure, the documentation of findings for the completion of the prosthetic restoration is also important. It is essential that these are available later on in the course of treatment. Especially for the evaluation of the crestal bone level of the individual implants, periapical radiographs still show the highest information density today. Digital archiving allows for a comparison of several images on the screen to assess, for example, the development of the peri-implant bone level.