Objective To assess the clinical and laboratory time efficiency and quality of outcomes for posterior single implant crowns by means of a model‐free digital workflow using digital impressions immediately after implant placement. Methods Forty patients missing a single posterior tooth received implant therapy. For within‐subject comparison, digital impressions were taken immediately after implant placement and conventional impressions after implant healing. Two monolithic zirconia crowns were fabricated using a laboratory‐based CAD‐CAM system. One crown was produced from the immediate digital impression and a model‐free digital workflow (test group), and the second crown was produced from the conventional impression and a hybrid workflow (control group). Clinical and laboratory time was recorded. Quality of outcomes was evaluated double‐blinded. A paired‐sample t test was applied for statistical analysis. Results The total mean chairside time (impression and delivery) was 23.2 min (95%CI 22.2, 24.3) in the test group and 25.7 min (95%CI 24.4, 26.9) in the control group (p = 0.013). Significantly less laboratory time was needed in the model‐free digital workflow (13.6 min, 95%CI 11.5, 15.6) as compared to the model‐based hybrid workflow (29.9 min, 95%CI 25.7, 34.2) (p < 0.05). At crown delivery, 4/40 (test) and 12/40 (control) had no need of chairside adjustments, and 6/40 (test) and 5/40 (control) implant crowns were in need of additional laboratory interventions. Conclusion The fabrication of posterior single implant crowns using digital impressions taken immediately after implant placement and a model‐free, laboratory‐based digital workflow was more time efficient and resulted in similar quality of outcomes as a hybrid workflow using conventional impressions.

Objectives To quantify the neighboring and antagonist teeth migration of a single posterior tooth‐missing site within 3 months using digital scanning and measuring techniques. Materials and Methods Intraoral scans (IOS) were made in 40 patients presenting a single posterior tooth‐missing gap and receiving implant therapy. IOS were obtained at the day of and three months after implant surgery rendering a digital baseline model (BM) and a digital follow‐up model (FM). Digital models were superimposed using the implant scan body as reference. Antagonist models were processed by the best fit alignment. Dimensional change between anatomical landmarks on neighboring teeth and that of featuring points on antagonistic teeth were measured using a three‐dimensional analysis software. The Mann–Whitney U test was applied to compare the tooth‐moving distance between the mesial and distal neighboring teeth. The Kruskal–Wallis one‐way ANOVA was used to test the difference in dimensional change in tooth‐missing site among age subgroups. Results The mean dimensional change in the tooth‐missing site was −37.62 ± 106.36 μm (median: −28.33 μm, Q25 −72.65/Q75 38.97) mesial‐distally and −67.91 ± 42.37 μm (median: −61.50 μm, Q25 −88.25/Q75 −36.75) occlusal‐gingivally. Eighteen out of 40 mesial neighboring teeth and 24 out of 40 distal neighboring teeth showed migration towards the implants. When patients were grouped according to age, the mesial‐distal reduction in the tooth‐missing site was significantly larger in patients younger than 30 years compared with those older than 50 years (p < .05). Conclusions The dimensions of posterior tooth‐missing sites decreased over an observation period of 3 months.

Aim To describe a comprehensive digital therapy oriented towards the final restoration for treating an oral maxillofacial defect caused by maxillary chondrosarcoma. Summary The prosthetically-driven multidisciplinary approach was applied to achieve perfectly functional-aesthetic reconstruction for a male patient with maxillary chondrosarcoma. The complete tumor resection was ensured by the design of virtual osteotomy and surgical guide plate. A reverse engineering technique was used to reconstruct the bone defect in the maxillary aesthetic area, which offered reference for a three-dimensional printing guide plate to shape and fix the free vascularized iliac bone flap. On the solid basis of previous treatment, the implant placement was performed under the guidance of the prosthetic-driven implant plate. Vestibular extension and tissue graft were performed to increase keratinized gingiva width to improve implant-supported fixed prosthesis effect. Key learning points 1. A multidisciplinary approach including maxillofacial surgery, prosthodontic and periodontal treatment can provide better esthetic and functional results for complex rehabilitation of a patient with oral maxillofacial defect. 2. Predictability of maxillary reconstruction and implant restoration can be increased with prosthetic-driven treatment plan. 3. Applying preoperative virtual design and personalized guide plate is beneficial to achieve an ideal outline of reconstructed upper jaw. 4. Obtaining comprehensive aesthetic parameters of the expected restoration is one of the key principles of upper anterior teeth rehabilitation. 5. Digital technology provides an opportunity for consistency between the primary treatment design and the final restoration outcome.