Objectives: The use of digital devices is strongly influencing the dental rehabilitation workflow both for single-crown rehabilitation and for full-arch prosthetic treatments. Methods: In this study, trueness was analyzed by overlapping the scan dataset made with Medit I-500 (by using two different tips and two different scan strategies) with the scan dataset made with lab scanning, and the values of the (90°–10°)/2 method were reported. Precision was evaluated by using the same values of trueness coming from the intra-group overlapping (scan dataset made with an IOS overlapped and compared to each other). Moreover, two different software programs of overlapping were used to calculate accuracy values. Results: The mean difference of trueness was 26.61 ± 5.07 µm with the suggested strategy of intraoral scanning and using a new design of the tip, 37.99 ± 4.94 µm with the suggested strategy of intraoral scanning and using the old design of the tip, and 51.22 ± 6.57 µm with a new strategy of intraoral scanning and using the old design of the tip. The mean difference of precision was 23.57 ± 5.77 µm with the suggested strategy of intraoral scanning and using a new design of the tip, 38.34 ± 11.39 µm with the suggested strategy of intraoral scanning and using the old design of the tip, and 46.93 ± 7.15 µm with a new strategy of intraoral scanning and using the old design of the tip. No difference was found in the trueness and precision data extracted using the two different programs of superimposition Geomagic Control X and Medit Compare. Conclusions: The outcomes of this study showed that the latest version of I-Medit 500 with the use of a new tip seems to be promising in terms of accuracy when a full arch needs to be scanned. Moreover, Medit Compare, which is an application of Medit IOS software, can be used to calculate IOS accuracy.
Zygomatic implant rehabilitation is a challenging procedure that requires an accurate prosthetic and implant plan. The aim of this study was to evaluate the malar bone available for three-dimensional zygomatic implant placement on the possible trajectories exhibiting optimal occlusal emergence. After a preliminary analysis on 30 computed tomography (CT) scans of dentate patients to identify the ideal implant emergencies, we used 80 CT scans of edentulous patients to create two sagittal planes representing the possible trajectories of the anterior and posterior zygomatic implants. These planes were rotated clockwise on the ideal emergence points and three different hypothetical implant trajectories per zygoma were drawn for each slice. Then, the engageable malar bone and intra- and extra-sinus paths were measured. It was possible to identify the ideal implant emergences via anatomical landmarks with a high predictability. Significant differences were evident between males and females, between implants featuring anterior and those featuring posterior emergences, and between the different trajectories. The use of internal trajectories provided better bone engagement but required a higher intra-sinus path. A significant association was found between higher intra-sinus paths and lower crestal bone heights.
The aim of this study was to evaluate the survival and clinical success rate, complications, and patients’ quality of life after computer-aided rehabilitation supported by zygomatic implants in cases of severe maxillary atrophy (ten patients) and in bone defects in oncologic patients (ten patients). All patients underwent computer-aided planning and surgery. Seventy-three zygomatic implants were placed. The mean follow-up period was 39.9 months. Implant survival and clinical success rate, the effectiveness of planning the implant length, biological and prosthetic complications, and the quality of life were evaluated. The five-year implant survival rate for patients with maxillary atrophy and oncologic patients was 97.4% and 96.7%, respectively. The prosthetic survival rate was 100%. Two implant failures occurred in the first year. One implant failure was observed in each group. Minor biological and prosthetic complications occurred in both groups without significant differences. All complications were managed without affecting the treatment. The quality of life increased by 71.3% in the atrophic group and by 82.9% in the oncologic group. Zygomatic implant rehabilitation seems to be a reliable technique for patients with maxillary atrophy and for oncologic patients. The three-dimensional computer-aided approach allows the surgeon to plan the surgery and increase its predictability. Early prosthesis loading certainly allows for better functional outcomes.
1 September 2021 in Journal of Stomatology Oral and Maxillofacial Surgery
Dynamic navigation (DN) is a computer-guided technique employed in different surgical fields and recently adopted in dental implantology to improve the accuracy of dental implant insertion. Medication-related osteonecrosis of the jaws (MRONJ) often requires the surgical removal of the impaired, hard tissue, trying at the same time to spare the healthy tissue and the noble anatomical structures. A case of extensive bilateral medication-related osteonecrosis, with the symptomatic involvement of the right mandibular canal, was successfully resolved with the use of ultrasonic surgery associated with a dynamic navigation, in order to limit the invasiveness of the surgical approach improving its reliability and accuracy. The usefulness of this technology in the management of MRONJ can be considered in future clinical trials to confirm the advantages and standardize the technique.