|dc.description.abstracteng||Today, periodontal diseases affect a large segment of the population and they are – together with caries – one of the major reasons for tooth loss. The diagnosis of periodontal diseases comprises a clinical and radiological diagnosis. In 2002, the German Society of Periodontology introduced the Periodontal Screening Index (PSI). This index serves the early detection of periodontal diseases. Consequently, the present thesis aims at comparing the two diagnostic methods, i.e. the PSI and the panoramic tomographic image, in order to draw conclusions as to their effectiveness and reliability in the evaluation of the given periodontal situation and in the derivation of the corresponding need for periodontal treatment. This question was worked on based on the analysis of existing data of recall patients with periodontal disease from the Department for Preventive Dentistry, Periodontology and Cariology of the University Medical Center of Göttingen.
Now, in order to be included in the study, X-ray and PSI results of the patients had to be taken within 12 months. Thus, we got 251 medical files that could be used for analysis. The radiological proof of bone loss was measured on the X-ray viewer by means of a millimetre-scaled periodontal probe. In accordance with the magnification factor of the panoramic tomographic image, this parameter was then subtracted from the measurement results in order to use the same scale for the X-ray that has also been used for the PSI test. Following the PSI categorisation, the radiologically detected bone loss was divided into three groups (Group 1: ≤ 3 mm, Group 2: 4-6 mm, Group 3: ≥ 7 mm).
When working with the PSI, we observed periodontitis in 93.2 % of the patients, which means that there was a need for treatment. These PSI scores were further subdivided as follows: score 0: 0 %, score 1: 0.8 %, score 2: 6 %, score 3: 36.6 % and score 4: 56.6 %. Within the sextants, however, the respective results changed. So with 46,3 %, PSI score 3 was on average the most frequent degree among the sextants. Besides, it turned out that the posterior region was more often affected by periodontal disease than the anterior region. The x-rays, in turn, indicated that 70.5 % of the analysed patients suffered from periodontitis and, within the sextants, also the majority of the patients had more measurement results indicating periodontal health when applying this technique.
Subsequently, the X-ray and PSI results were compared as to their “overall performance”, their “performance within the sextants” and – in case of 60 medical files – a “direct comparison between measuring points” was conducted. When comparing the overall performance, we could observe coincident diagnoses in 77.3% of the cases. Within the sextants, we had to subdivide the cases with no coincidence into the group of “X-ray indicating no periodontitis/PSI indicating periodontitis (33-55 %)“ and, viceversa, the group of „X-ray indicating periodontitis/PSI indicating no periodontitis“. The by far smallest subgroup, with a maximum of 4.5 %, was here formed by the number of cases where only the X-ray gave rise to the diagnosis of periodontitis. This means that the panoramic tomographic image and the PSI lead to different diagnoses, with the PSI detecting periodontal disease more often. Besides, in clinical practice this index has an accurate definition and is more easily reproducible. As, therefore, the PSI seems to identify periodontal diseases more critically and at an earlier stage, it should be the method of choice for the initial diagnosis. Just working with X-ray is not sufficient to detect the need for periodontal treatment especially during early stages of disease development because this method does not show in particular initial lesions. Thus, this method plays an ancillary role in the process of finding a diagnosis but is of major importance for the subsequent diagnoses.||de