The Influence of Local Pamidronate Application on Alveolar Dimensional Preservation after Tooth Extraction-An Animal Experimental Study.

The aim of this randomized, controlled animal exploratory trial was to investigate the influence of local application of aminobisphosphonate pamidronate during the socket preservation procedure. Mandibular premolars were extracted in five Göttingen minipigs. Two animals underwent socket preservation using BEGO OSS (n = 8 sockets) and three animals using BEGO OSS + Pamifos (15 mg) (n = 12 sockets). After jaw impression, cast models (baseline, eight weeks postoperative) were digitized using an inLab X5 scanner (Dentsply Sirona) and the generated STL data were superimposed and analyzed with GOM Inspect 2018 (GOM, Braunschweig). After 16 weeks, the lower jaws were prepared and examined using standard histological methods. In the test group (BEGO OSS + pamidronate), buccooral dimensional loss was significantly lower, both vestibulary (0.80 ± 0.57 mm vs. 1.92 ± 0.63 mm; p = 0.00298) and lingually (1.36 ± 0.58 mm vs. 2.56 ± 0.65 mm; p = 0.00104) compared with the control group (BEGO OSS). The test group showed a significant difference between vestibular and lingual dimensional loss (p = 0.04036). Histology showed cortical and cancellous bone in the alveolar sockets without signs of local inflammation. Adjuvant application of pamidronate during socket preservation reduces alveolar dimensional loss significantly. Further investigations with regard to dose-response relationships, volume effects, side effects, and a verification of the suitability in combination with other bone substitute materials (BSMs) are necessary.

Evaluation of Periodontal Space Widening in Patients with Antiresorptive Drug-related Osteonecrosis of the Jaws (ARONJ) on Panoramic Radiographs.

BACKGROUND/AIM: The purpose of this study was to evaluate a potential widening of the periodontal space as an initial measurable imaging criterium on panoramic radiographs in patients with the diagnosis of antiresorptive drug related osteonecrosis of the jaw (ARONJ). PATIENTS AND METHODS: A retrospective analysis of panoramic radiographs of 16 patients (12 females and 4 males; mean age is 70.5 years, standard deviation is 14 years) was performed, over a period of 12 months with the diagnosis of ARONJ. Panoramic radiographs of 16 healthy patients (12 females and 4 males; mean age was 70.6 years, standard deviation was 13.8 years) without diagnosis of ARONJ served as controls. All images were taken with the same device and were evaluated by two experienced maxillofacial surgeons and one dentist. RESULTS: Compared to the control group, a mean widening of the periodontal space of 0.06 mm (confidence interval (CI)=0.05-0.17 mm) was found in the study group. However, this difference was not statistically significant. CONCLUSION: Although a very extensive and sophisticated interindividual comparison was performed to evaluate for slight changes of the periodontal space in patients with antiresorptive drug therapy, our results demonstrate that PDS widening is not a predictive parameter for ARONJ. Therefore, our results indicate that panoramic radiographs are not sufficient enough to allow assessment of stages and disease progress in ARONJ patients regarding to periodontal space widening.

Accuracy of Bone Measurements in the Vicinity of Titanium Implants in CBCT Data Sets: A Comparison of Radiological and Histological Findings in Minipigs.

PURPOSE: The aim of this animal study was the determination of accuracy of bone measurements in CBCT (cone-beam computed tomography) in close proximity to titanium implants. MATERIAL AND METHODS: Titanium implants were inserted in eight Göttingen minipigs. 60 implants were evaluated histologically in ground section specimen and radiologically in CBCT in regard to thickness of the buccal bone. With random intercept models, the difference of histologic measurements and CBCT measurements of bone thickness was calculated. RESULTS: The mean histological thickness of the buccal bone was 5.09 mm (CI 4.11-6.08 mm). The four raters measured slightly less bone in CBCT than it was found in histology. The random effect was not significant (p value 1.000). Therefore, the Intraclass Correlation Coefficient (ICC) was 98.65% (CI 100.00-96.99%). CONCLUSION: CBCT is an accurate technique to measure even thin bone structures in the vicinity of titanium implants.

Artefacts in multimodal imaging of titanium, zirconium and binary titanium-zirconium alloy dental implants: an in vitro study.

OBJECTIVES: To analyze and evaluate imaging artefacts induced by zirconium, titanium and titanium-zirconium alloy dental implants. METHODS: Zirconium, titanium and titanium-zirconium alloy implants were embedded in gelatin and MRI, CT and CBCT were performed. Standard protocols were used for each modality. For MRI, line-distance profiles were plotted to quantify the accuracy of size determination. For CT and CBCT, six shells surrounding the implant were defined every 0.5 cm from the implant surface and histogram parameters were determined for each shell. RESULTS: While titanium and titanium-zirconium alloy induced extensive signal voids in MRI owing to strong susceptibility, zirconium implants were clearly definable with only minor distortion artefacts. For titanium and titanium-zirconium alloy, the MR signal was attenuated up to 14.1 mm from the implant. In CT, titanium and titanium-zirconium alloy resulted in less streak artefacts in comparison with zirconium. In CBCT, titanium-zirconium alloy induced more severe artefacts than zirconium and titanium. CONCLUSIONS: MRI allows for an excellent image contrast and limited artefacts in patients with zirconium implants. CT and CBCT examinations are less affected by artefacts from titanium and titanium-zirconium alloy implants compared with MRI. The knowledge about differences of artefacts through different implant materials and image modalities might help support clinical decisions for the choice of implant material or imaging device in the clinical setting.

Postoperative bleeding risk for oral surgery under continued clopidogrel antiplatelet therapy.

OBJECT: To determine the incidence of postoperative bleeding for oral osteotomy carried out under continued monoantiplatelet therapy with clopidogrel and dual therapy with clopidogrel/aspirin. Design. Retrospective single center observatory study of two study groups and a control group. METHODS: A total of 64 and 60 oral osteotomy procedures carried out under continued monoclopidogrel therapy and dual clopidogrel/aspirin therapy, respectively, were followed for two weeks for postoperative bleeding. Another 281 similar procedures were also followed as a control group. All oral osteotomy procedures were carried out on an outpatient basis. RESULTS: We observed postoperative bleeding in 2/281 (0.7%) cases in the control group, in 1/64 (1.6%) cases in the clopidogrel group, and in 2/60 (3.3%) cases in the dual clopidogrel/aspirin group. The corresponding 95% confidence intervals are 0-1.7%, 0-4.7%, and 0-7.8%, respectively, and the incidences did not differ significantly among the three groups (P > 0.09). Postoperative hemorrhage was treated successfully in all cases with local measures. No changes of antiplatelet medication, transfusion, nor hospitalisation were necessary. No major cardiovascular events were recorded. CONCLUSIONS: Our results indicate that minor oral surgery can be performed safely under continued monoantiplatelet medication with clopidogrel or dual antiplatelet medication with clopidogrel/aspirin.