Objectives: The main goal of this study was to compare the soft-tissue volume gain around dental implants with subepithelial connective tissue grafts (SCTG) originating from either palate or the tuberosity. The secondary goal was to compare changes in clinical parameters: plaque index (PI), bleeding on probing (BOP), probing depth (PD) and width of keratinised tissue (KT). Methods: Patients with single tooth implants already osseointegrated and in need of soft tissue augmentation were recruited (n = 12) and randomly received an SCTG from the palate (control group) or tuberosity (test group). Recipient sites were prepared by an intracrevicular incision at the buccal side extending to one adjacent tooth on each side, before raising a partial-thickness flap. Grafts of standarised dimensions were stabilised to the buccal flap and closure was achieved without tension. In order to examine volumetric tissue changes, an intraoral optical scanner was used to take two optical impressions at baseline and again 3 months after surgery. Digital software was used to superimpose the stereolithography (STL) files and calculate volume gain. Volumetric changes were calculated at three levels below the healing abutment on the buccal side of the implants (at 1.3mm and 5.0mm). The secondary outcomes
were evaluated at baseline and at 3 months. Differences between control and teset groups were calculated for the quantitative variables using the Student’s t-test or Mann–Whitney test (depending on the normality of the distribution) and Chi-squared test for the qualitative variables. A p value of Results: No significant differences in baseline defect size were observed between groups. At 1mm volume gain was 1.28 ± 0.89mm for palate grafts (controls) and 1.28 ± 0.83mm for tuberosity grafts(p=0.39); at 3mm it wasoriginal, 84 ± 1.21mm for palate and 1.1 ± 0.4mm for tuberosity (p=0.31); and at 5mm it was 0.66 ± 0.23mm for palate and 0.95 ± 0.48mm for tuberosity (p=0.39). No statistically significant differences were observed at any level. The tuberosity grafts had a higher volume gain with a mean gain of 1.12 ± 0.57mm (versus a mean gain of 0.88 ± 0.94mm for palate), but these results were not statistically significant (p=0.42). Similarly, there was a tendency for higher KT gain for the tuberosity group, with an increase of 1.16 ± 0.98mm, versus 0.66 ± 0.82mm (p=0.36). A statistically significant reduction in PI was observed for the controls, from 18.0 ±0.89% to 16.3 ±1.03% (p=0.01), but only a slight (non-statistically) significant increase was seen in the test group. Non-statistically significant differences were also observed for PB and BOP. Conclusion: The main goal of this study was to compare the soft-tissue volume gain around dental implants using SCTGs of the same dimensions from either palate or tuberosity. Although the present data is only preliminary, procedures were effective in increasing volume gain around the implants at 3 months. Differences were statistically non-significant, but there was a tendency for increased volume gain with SCTGs from the tuberosity (1.12±0.57mm) compared to palate (0.88±0.94mm). Furthermore, there was a tendency towards for greater KT gain in the tuberosity group (1.16±0.98mm versus 0.66±0.82mm in the palate group).

Chirurgie: Aufklappung und Lappenbildung, Festlegung der Implantatposition mittels Bohrschablone, Anlage der Implantatstollen, Gewindeschneiden, Knochenverdichtung, Insertion der Implantate, Abformung, Wundverschluss, spätere Eingliederung. Zahntechnik: Modellherstellung mit Laborimplantaten, Modellation des Steggerüstes, Adaption des lasergeschweißten Gerüstes auf dem Modell, Herstellung des Zahnersatzes, Einarbeiten der Stegreiter in den Zahnersatz, Fertigstellung.

The bone healing process in people can be affected by diseases such as Crohn’s disease, diabetes and colitis. It can also be affected by drugs such as bisphosphonates, which are used to treat weak bones in people with osteoporosis, Paget's disease and certain cancers. The role of animal models is enormous for investigating these disease conditions as well as other “risk factors” for compromised healing, such as radiotherapy, which is being increasingly used as early treatment of cancer in the community rises. Diabetes and intestinal disorders can be induced in rats, often using chemicals with toxic effects, but the diseases can take some time to develop. This chapter gives guidance on various timeframes for evaluating inflammatory processes, osseointegration and collagen cross-linking, and gives details on mechanical strength testing of dental implants and other candidate therapies. Different aspects of the compromised bone healing response can be observed using both the long bones (tibia and femur) and the maxilla of rats. This chapter also describes an adaptable study protocol for new investigators, with suitable endpoints such as bone to tissue ratio and bone to implant contact, to contribute to the body of knowledge on patients with compromised bone healing who are increasingly encountered in dental practice.