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The problems caused by proximal contact loss (PCL) of dental implants have been a mainstream research topic in recent years, and scholars are unanimously committed to analyzing their causes and related factors, aiming to identify solutions to the problems related to PCL. The effects of the anterior component of force (ACF), the lifelong remolding of the adult craniofacial jaw and alveolar socket, and the osseointegration characteristics of dental implants are the main causes of PCL. On the one hand, the closing movement of the mandible causes the ACF of the tooth to move through the posterior molar cusp. Moreover, drifting between the upper and lower posterior teeth and mandibular anterior teeth can cause the anterior teeth of the upper and lower jaws to be displaced labially. On the other hand, reconstruction of the jaw, alveolar socket and tooth root, the forward horizontal force of the masticatory muscles, the dynamic component of the jaw and the forward force generated by the oblique plane of the tooth cusp can cause the natural tooth to experience near-middle drift. Additionally, natural teeth can shift horizontally and vertically and rotate to accommodate remodeling of the stomatognathic system and maintain oral function. Nevertheless, the lack of a natural periodontal membrane during implant osseointegration, the lack of a physiological basis for near-medium drift, the small average degree of vertical motion and the integrated silence of dental implants without the overall drift characteristics of natural teeth increases the probability of PCL. The high incidence of PCL is clearly associated with the duration of prosthesis delivery and the mesial position; but it is also affected by the magnitude of the bite force, occlusion, the adjacent teeth, restoration design, implant location, jaw, and patient age and sex. PCL has shown a significant correlation with food impaction, but not a one-to-one correspondence, and did not meet the necessary and sufficient conditions. PCL is also associated with peri-implant lesions as well as dental caries. PCL prevention included informed consent, regular examinations, selection of retention options, point of contact enhancement, occlusal splints, and the application of multipurpose digital crowns. Management of the PCL includes adjacent contact point additions, orthodontic traction, and occlusal adjustment. Existing methods can solve the problem of food impaction in the short term with comprehensive intervention to seek stable, long-term effects. Symmetric and balanced considerations will expand the treatment of issues caused by PCL.

Objectives: To analyze the three‐dimensional stability and morphologic changes of tent space after the osteotome sinus floor elevation (OSFE) procedures without bone grafts. Materials and Methods: Forty‐six implants placed using the OSFE technique with simultaneous implant placement without bone grafts were included in this retrospective study. Cone‐beam computed tomography (CBCT) scans of the augmented sinuses were obtained pre‐ and postoperatively up to 48 months of follow‐up. The maxillary sinus cavity profiles were outlined using three‐dimensional virtual reconstruction and superimposition of CBCT scans. The three‐dimensional changes in the tent space were measured. A generalized estimating equation (GEE) was used to explore potential factors. Results: The implant survival rate was 97.8%. The mean volume of remaining tent space immediately after surgery was 96.8 ± 70.5 mm3, shrinking to 31.0 ± 24.9 mm3 after 48 months, while the mean percentage of remaining tent space volume decreased to 29.1 ± 20.7%. The tent space volume and the percentage of residual tent space volume only decreased significantly within 12 months after surgery (p =.008,.013). GEE results indicated positive correlations between the percentage of remaining tent space volume and implant protrusion length (p =.000) and apical height (p =.000), with a negative correlation between the sinus floor area immediately after surgery (p =.002) and the healing time (p =.022). Conclusions: The volume of the tent space rapidly shrank after OSFE without bone grafts. Several factors might influence the tent space stability. Long‐term clinical trials with larger sample sizes are necessary to further validate the results. [ABSTRACT FROM AUTHOR]

This paper studies 10 Asian economies' experiences during two episodes of financial crises in 1997–08 and 2007–09. Our analysis of five crisis‐hit Asian countries shows that overinvestment via credit expansion and foreign financing has an adverse effect on banking sectors while income inequality contributes significantly to financial distress. With five no‐crisis emerging markets included in our Asia analysis, we find that export‐oriented growth backed up by domestic savings is financially less risky than investment‐led growth facilitated by capital inflows. Since such different strategies of output growth to deal with falling demand are related ultimately to the same factor–rising inequality, this distributional problem must be overcome effectively to enhance financial stability and ensure growth sustainability. [ABSTRACT FROM AUTHOR]

Rehabilitation and reconstruction of atrophic edentulous predicament represents significant challenges for implant dentists due to the anatomical conditions of the edentulous jaw. Implant-supported fixed complete dental prostheses represent a scientifically and clinically validated treatment for recovering patients, masticatory function and esthetic effect. However, the highly demanding implant surgical techniques and complex rehabilitation procedures for immediate functional reconstruction make it difficult to achieve the desired treatment outcomes. The application of digital and CAD/CAM technology in various stages of the treatment process is logical for patients and dentists. This article summarizes the workflow of digital-assisted implantation with immediate functional reconstruction of atrophic edentulous combined with a clinical case. Digital-assisted diagnosis, design, implantation, immediate reconstruction and final rehabilitation can optimize the implant surgery and immediate rehabilitation workflow, improve the accuracy of implant-supported immediate functional reconstruction, reduce the demand for a large amount of bone graft, and achieve higher patient satisfaction. The “prosthetic-oriented, begin with the end in mind” concept of edentulous jaw implant prosthetics can accurately and efficiently restore the patient,s beauty and chewing function in a minimally invasive manner, and is worthy of clinical promotion.

This article extends Fama and French (FF) models of observed factors by introducing latent factors (LFs) to further extract information from FF residual returns. A diagonally dominant (DD) rather than a diagonal or sparse matrix structure is adopted in this study to estimate remaining covariance between disturbance terms. Such an enhanced factor (EF) model provides a more comprehensive analysis for portfolio selection in high dimensions and also has certain advantages of estimation stability and computational efficiency. It is shown that the proposed EF–DD approach achieves overall better performance than competing models in terms of portfolio variance and the net Sharpe ratio. [ABSTRACT FROM AUTHOR]