One-Stage Vertical Ridge Augmentation and Dental Implantation With Allograft Bonerings: Results 1 Year After Surgery.

The aim of this study was to analyze the success rate of dental implants and the graft shrinkage rate after vertical ridge augmentation and simultaneous implantation with an allograft bonering. Fifty-one patients (81 augmentations and simultaneous implantations) were included. The bonering technique followed a standardized protocol. The alveolar ridge was prepared using a congruent trephine, and depending on the defect size, an allograft bonering with an outer diameter of 6-7 mm was placed. The height of the bonering was trimmed with a diamond disc to the required length. The average height of vertical augmentation was 5.5 mm. Implants were inserted through the bonering into the native bone of alveolar ridge. After 6 months, dental implants were exposed, and dental prosthetics were placed. Of 81 implants placed with the bonering technique, two failed during a 12-month follow-up, corresponding to a success rate of 97.5%. One year after surgery, the allograft bonering exhibited an average vertical graft shrinkage rate of 8.6%. In conclusion, the allograft bonering technique was associated with a favorable outcome, and in cases with large vertical defects, both treatment time and donor site morbidity could be reduced.

Image analysis of immediate full-arch prosthetic rehabilitations guided by a digital workflow: assessment of the discrepancy between planning and execution.

BACKGROUND: A dentition with adequate function and esthetics is essential for the well-being and quality of life. A full implant-retained fixed prosthetics is an ideal solution for fully edentulous arch, however requires complex planning, surgical, and prosthetic procedure. With the help of digital workflow, it becomes a predictable and fast solution for the dentists and the patients. This retrospective study analyzed the most advanced surgical approach in full-arch rehabilitation with dental implants and immediate loading using digital workflow. METHODS: Patient records of fully edentulous jaws treated in four clinical centers in Warsaw, Poland, were evaluated. Computer-assisted planning and surgical template fabrication were done using the planning software coDiagnostiX™, based on a pre-op cone beam computed tomography (CBCT) and scanned data of a plaster model. A post-op CBCT was acquired after the placement of four to six implants by the guided system. The influence of different surgical variables on the discrepancy between planning and execution was analyzed, together with the biomechanical indices. RESULTS: A total of nine patient records were selected of 12 edentulous jaws treated with 62 implants. The overall mean three-dimensional (3D) offset at the implant base was 1.60 mm, at the tip 1.86 mm. The mean angle of deviation was 4.89°, the mean implant stability quotient (ISQ) 70.42, and the insertion torque 35.58 Ncm. The 3D offsets were influenced by the gender of the patient, treated jaw, the diameter, and length of the implant. The angle of deviation was affected only by the treated jaw. Insertion torque was influenced by the treated jaw, the age of the patient, the length of the implant, tooth type, and the side of the jaw. DISCUSSION: Bone quality of the patient and implant preparation procedure influenced the discrepancy between the planning and the execution of the digitally guided implant placement. Dense bone-mandible, posterior area, young age, and man-and multiple preparations of the implant bed-wider and longer implant-could be suggested as risk factors. CONCLUSION: Digital workflow successfully enabled the immediate full-arch rehabilitation with a predictable outcome by different surgeons in multiple centers.

Comparison of autogenous and allograft bone rings in surgically created vertical bone defects around implants in a sheep model.

OBJECTIVES: The aim of this study was to compare autogenous and allograft bone rings in surgically created vertical bone defects. MATERIAL AND METHODS: Four male, 1-year-old sheep were used in this study. In each sheep, eight vertical bone defects 7 mm in diameter were created using trephine drill in the iliac wing. Autogenous and allograft bone rings 5 mm in height and 7 mm in diameter were used for vertical augmentation around implants. The study consisted of four groups according to the bone ring type and amount of vertical augmentation, autogenous 2 mm, allograft 2 mm, autogenous 4 mm, and allograft 4 mm. Two of the animals were sacrificed after 4 months, and the remaining two animals were sacrificed after 8 months. Undecalcified sections were prepared from harvested samples. Histological assessment and histomorphometric analysis were performed. RESULTS: Autogenous 2 mm group showed higher values than allograft 2 mm group, and autogenous 4 mm group showed higher values than allograft 4 mm group in terms of bone area and bone-to-implant contact (BIC) after 4 months. However, allograft 2 mm group showed higher bone area and BIC values than autogenous 2 mm group after 8 months. Also, autogenous 4 mm and allograft 4 mm groups showed comparable results after 8 months. Allograft 2 mm and allograft 4 mm groups showed higher bone area and BIC values at 8 months compared with 4 months. CONCLUSIONS: Allograft bone ring looks promising in augmentation of surgically created vertical bone defects around implants after 8 months of healing.