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Background: Large antroliths and those located adjacent to the sinus floor can affect clinical interventions and increase the difficulty of implant placement performed simultaneously with osteotome sinus floor elevation surgery. Purpose: This retrospective study investigated the clinical outcomes of implants placed simultaneously with osteotome sinus floor elevation subjacent to maxillary antroliths. Material and methods: Twenty implants inserted subjacent to or intruding into the antrolith after sinus floor elevation were evaluated in 18 patients. Cone‐beam computed tomography (CBCT) was used to measure antrolith size and membrane thickness at sites of osteotome sinus floor elevation. Periapical radiographs were used to assess the height of grafted bone. Generalized estimating equation (GEE) analysis was performed to correlate the occurrence of antroliths with patient background characteristics and dental outcomes, based on a sample population of 239, among whom 33 presented antroliths. Results: The 20 implants remained clinically stable over a mean follow‐up period of 42.4 months. The mean thickness of the sinus membrane at osteotome sites was 5.4 ± 3.3 mm. None of the cases presented sinus membrane perforation or sinus symptoms following osteotome intervention. The mean gain in the height of grafted sinus bone was 4.0 ± 1.4 mm at the last follow‐up. The occurrence of antroliths was higher among females and the elderly (>49 years old). The multivariable GEE analysis showed that the adjusted odds ratio for the occurrence of antroliths with root canal fillings was significantly lower than those without root canal fillings (odds ratio = 0.33; 95% confidence interval = 0.11–0.96). Conclusion: Our findings indicate that osteotome sinus floor elevation is a surgical procedure with a risk <17%. Thorough planning based on CBCT and careful management during surgery can eliminate the negative effects of antroliths on implant performance. [ABSTRACT FROM AUTHOR]

This paper proposes a scaffolded concept mapping strategy, which considers a student's (high or low) prior knowledge, and provides flexible learning aids (scaffolding and fading) for reading and drawing a concept map. The goal is that the whole class should progress in synchronized fashion through this strategy, with each student achieving meaningful learning. The scaffolding is tailored to the student's needs, with various levels of support. The increasing demand for scaffolding, and its constant evolution, means that software aids are needed. The authors adopted a systematic instructional design, with associated software, to create a learning environment that supports the execution of the strategy. The paper also investigates whether this strategy improved student learning for 54 undergraduates in a database management system course. The results indicate that the students who used the strategy had better learning achievements than those who only experienced traditional lectures. Moreover, the implementation of the strategy received positive student feedback. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess the risk of less than 2 mm keratinized mucosa (KM) width occurrence after free epithelialized graft (FEG) and keratinized mucosa shifting (KMS) procedures using survival analysis. In addition, KM dimensional changes were evaluated. Materials and Methods: This study included 76 implants in 36 patients with insufficient KM (<2 mm). The implants underwent either FEG or KMS procedures. The mid‐buccal KM width was measured from surgery to the end of a one 13‐year follow‐up period. Results: Mean follow‐up durations were 9.2 ± 3.9 years for FEG and 6.3 ± 4.2 years for KMS. Two implants in FEG and nine implants in KMS exhibited a KM width of less than 2 mm during follow‐up. The hazard ratios for KMS compared to FEG were 6.48 (crude) and 6.54 (adjusted), both statistically significant (p <.05). The incidence rate of KMS (4.06%) was higher than that of FEG (0.63%), with an average incidence time of 3.38 years for KMS and 8.82 years for FEG post‐surgery. FEG showed a significant shrinkage within 6 months (33% ± 22%), whereas KMS demonstrated a gradual decrease over 13 years (34% ± 25%). FEG exhibited significantly greater width change than KMS during a 5‐year follow‐up (p <.05). Conclusions: FEG and KMS enhanced PIKM but exhibited different long‐term reduction patterns. FEG demonstrated rapid shrinkage, while KMS displayed gradual and continuous reduction. Moreover, KMS presented a higher risk and incidence of KM width less than 2 mm compared to FEG. [ABSTRACT FROM AUTHOR]

It is essential that airlines efficiently perform aircraft maintenance in order to ensure aviation safety and schedule punctuality. Traditionally, the arrangement of the maintenance manpower supply has been based on staff experience, and has been performed manually following simple rules. This is not only time-consuming but often ineffective. In this research we consider technicians with multiple types of aircraft maintenance certificates incorporated with three flexible management strategies and the related operating constraints to develop a mathematical programming model. With suitable modifications, eight different flexible strategic models, associated with different strategy combinations, can be generated to help an airline effectively manage its maintenance manpower supply. The models are formulated as mixed integer programs. Because the problem sizes of the proposed models are expected to be huge in real applications, we have developed a solution algorithm to efficiently solve the problems. We employed the mathematical programming solver, CPLEX, to reach a solution for all the problems. Finally, to evaluate the models and solution algorithm developed in the research, we performed a case study using the operating data from a leading Taiwan airline. The preliminary results indicate that the proposed models, and the solution algorithm, are both efficient and effective. [Copyright &y& Elsevier]