Autologous Transplantation Tooth Guide Design Based on Deep Learning.

BACKGROUND: Autologous tooth transplantation requires precise surgical guide design, involving manual tracing of donor tooth contours based on patient cone-beam computed tomography (CBCT) scans. While manual corrections are time-consuming and prone to human errors, deep learning-based approaches show promise in reducing labor and time costs while minimizing errors. However, the application of deep learning techniques in this particular field is yet to be investigated. PURPOSE: We aimed to assess the feasibility of replacing the traditional design pipeline with a deep learning-enabled autologous tooth transplantation guide design pipeline. STUDY DESIGN, SETTING, SAMPLE: This retrospective cross-sectional study used 79 CBCT images collected at the Guangzhou Medical University Hospital between October 2022 and March 2023. Following preprocessing, a total of 5,070 region of interest images were extracted from 79 CBCT images. PREDICTOR VARIABLE: Autologous tooth transplantation guide design pipelines, either based on traditional manual design or deep learning-based design. MAIN OUTCOME VARIABLE: The main outcome variable was the error between the reconstructed model and the gold standard benchmark. We used the third molar extracted clinically as the gold standard and leveraged it as the benchmark for evaluating our reconstructed models from different design pipelines. Both trueness and accuracy were used to evaluate this error. Trueness was assessed using the root mean square (RMS), and accuracy was measured using the standard deviation. The secondary outcome variable was the pipeline efficiency, assessed based on the time cost. Time cost refers to the amount of time required to acquire the third molar model using the pipeline. ANALYSES: Data were analyzed using the Kruskal-Wallis test. Statistical significance was set at P < .05. RESULTS: In the surface matching comparison for different reconstructed models, the deep learning group achieved the lowest RMS value (0.335 ± 0.066 mm). There were no significant differences in RMS values between manual design by a senior doctor and deep learning-based design (P = .688), and the standard deviation values did not differ among the 3 groups (P = .103). The deep learning-based design pipeline (0.017 ± 0.001 minutes) provided a faster assessment compared to the manual design pipeline by both senior (19.676 ± 2.386 minutes) and junior doctors (30.613 ± 6.571 minutes) (P < .001). CONCLUSIONS AND RELEVANCE: The deep learning-based automatic pipeline exhibited similar performance in surgical guide design for autogenous tooth transplantation compared to manual design by senior doctors, and it minimized time costs.

Cellulose-based polypropoxy ether carboxylates as highly compatible, effective, and migration-resistant plasticizers for poly (lactic acid).

The utilization of cellulose for enhancing the strength, the PLA has received significant attention, however, poor interfacial compatibility of solid cellulose with PLA matrix still hinders their broader application. Herein, highly compatible cellulose-based polypropoxy ether carboxylates (CPPEC) were firstly manufactured via propoxylation of cellulose and following esterification with acetic acid, butyric acid, as well as oleic acid, respectively. Liquid CPPEC delivered excellent performances to PLA, especially, the values of elongation at break and low-temperature resistance of PLA blended with cellulose-based polypropoxy ether acetate (PLA/CPPEA) were respectively increased by 630.9 % and 146.3 % compared with those of neat PLA due to the synergistic effect of propyl and methyl groups in CPPEC with PLA matrix. Additionally, migration resistance of PLA/CPPEA increased 14.3 and 11.2 times, respectively, compared with those of PLA specimens blended with epoxidized soybean oil and dioctyl phthalate. All findings suggest that the CPPEC is suitable for large-scale application in the PLA industry.