Background: With the rise of new 3D printers, assessing accuracy is crucial for obtaining the best results in patient care. Previous studies have shown that the highest accuracy is achieved with SLS printing technology; however, SLA printing technology has made significant improvements in recent years. Methods: In this study, a realistic anatomical model of a mandible and skull, a cutting guide for mandibular osteotomy, and a splint for orthognathic surgery were replicated five times each using two different 3D printing technologies: SLA and SLS. Results: The SLA group had a median trueness RMS value of 0.148 mm and a precision RMS value of 0.117 mm. The SLS group had a median trueness RMS value of 0.144 mm and a precision RMS value of 0.096 mm. There was no statistically significant difference in RMS values between SLS and SLA technologies regarding trueness. Regarding precision, however, the RMS values for SLS technology were significantly lower in the splint and cutting guide applications than those printed with SLA technology. Conclusions: Both 3D printing technologies produce modern models and applications with equally high dimensional accuracy. Considering current cost pressures experienced by hospitals, the lower-cost SLA 3D printer is a reliable choice for point-of-care 3D printing.

Nilius M, et al. J Dent Anesth Pain Med. 2020 Dec;20(6):367-375. https://doi.org/10.17245/jdapm.2020.20.6.367

The mandible plays an essential part in human life and, thus, defects in this structure can dramatically impair the quality of life in patients. Axolotls, unlike humans, are capable of regenerating their lower jaws; however, the underlying mechanisms and their similarities to those in limb regeneration are unknown. In this work, we used morphological, histological and transcriptomic approaches to analyze the regeneration of lateral resection defects in the axolotl mandible. We found that this structure can regenerate all missing tissues in 90 days through gap minimization, blastema formation and, finally, tissue growth, differentiation and integration. Moreover, transcriptomic comparisons of regenerating mandibles and limbs showed that they share molecular phases of regeneration, that these similarities peak during blastema stages and that mandible regeneration occurs at a slower pace. Altogether, our study demonstrates the existence of a shared regenerative program used in two different regenerating body structures with different embryonic origins in the axolotl and contributes to our understanding of the minimum requirements for a successful regeneration in vertebrates, bringing us closer to understand similar lesions in human mandibles.

This multi-center retrospective study evaluated the survival and success of extra-short and short locking-taper dental implants placed in both maxillary and mandibular fibula grafts. A total of 37 patients were treated across five study sites and received 146 implants in fibula grafted sites. Out of those patients, 23 received prostheses, and they received 25 prostheses in total. Kaplan-Meier survival analysis was used to assess the survival and success rates of both implants and prostheses. Multivariate Cox regression and manifold learning were used to correlate study covariates to implant survival outcomes. Marginal bone levels surrounding implants supporting full arch prostheses were measured and correlated with the lengths of distal extensions. The overall thirteen-year implant survival rate was 86.9 % (95 % confidence interval: 75.5-93.2 %), while the implant success rate was 80.2 % (95 % confidence interval: 66.8-88.7 %.) The prosthesis survival rate at 13 years after prosthesis insertion was 90.0 % (95 % confidence interval: 65.6-97.4 %); while the prosthetic success rate was 78.9 % (95 % confidence interval: 56.2-90.7 %.) Hypertension, implant placement in the mandible, tooth loss from tumor, patient age, and lateral augmentation were correlated with reduced implant survival; while maxillary implant placement, osteoporosis and antiresorptive drug use, chemotherapy before implant surgery, and tooth loss from trauma were correlated with improved survival. Marginal bone levels around implant immediately adjacent to distal extensions were positively correlated with the lengths of distal extensions (R² = 0.74). Extra short and short locking-taper dental implants presented high survival and success rates when used to restore the dentition of patients receiving fibula grafts for maxillary or mandibular reconstruction.

Purpose . In cases of severe atrophic maxilla or maxillary involution, augmentation is necessary for implant‐supported prosthetics. Using bone grafts is a standard procedure, and using customized allogeneic bone blocks may be a predictable alternative before dental implantation. Clinical Findings . This case study shows the digital workflow, including a preimplantological augmentation by a customized allogeneic block, followed by soft tissue optimization and template‐based dental implantation, after six months of healing. It is part of a three‐year follow‐up study on the resorption rate of allogeneic bone blocks. Outcomes . Allogeneic bone augmentation is an alternative treatment option to autologous bone grafts. It allows predictable advanced backward planning (ABP) even in the maxillary esthetic zone. Diameter‐reduced implants show long‐term stability of a minimum of three years after loading and excellent results of prosthetic fixtures. Conclusion . Prefabricated customized allogeneic blocks for augmentation may increase the fitting accuracy of the graft, decrease morbidity, and reduce the operation time in esthetic maxillary rehabilitation.

The mandible plays an essential part in human life and, thus, defects in this structure can dramatically impair the quality of life in patients. Axolotls, unlike humans, are capable of regenerating their lower jaws; however, the underlying mechanisms and their similarity to those in limb regeneration are unknown. In this work, we used morphological, histological, and transcriptomic approaches to analyze the regeneration of lateral resection defects in the axolotl mandible. We found that this structure can regenerate all missing tissues in 90 days through gap minimization, blastema formation, and finally tissue growth, differentiation, and integration. Moreover, transcriptomic comparisons of regenerating mandibles and limbs showed that they share molecular phases of regeneration, that these similarities peak during blastema stages, and that mandible regeneration occurs at a slower pacing. Altogether, our study demonstrates the existence of a shared regenerative program used in two different regenerating body structures with different embryonic origins in the axolotl, and contributes to our understanding of the minimum requirements for a successful regeneration in vertebrates, bringing us closer to understand similar lesions in human mandibles.