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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.

Sinus floor elevation is the most commonly used method for vertical bone augmentation in the maxillary posterior area. This clinical report describes a modified transalveolar approach to elevate the Schneiderian membrane when placing implants on a severely resorbed maxillary posterior ridge with a buccal-palatal width of more than 8.0 mm. In this approach, the osteotomy prepared on the crestal is bilaterally enlarged to 8.0–10.0 mm. The enlarged osteotomies provide better access, allowing instruments to be in direct contact with the bone of the sinus floor and thus elevate the Schneiderian membrane with a reduced risk of perforation. [ABSTRACT FROM AUTHOR]

This clinical report describes a combined lateral-crestal approach to elevate the sinus floor when placing implants on a wide maxillary posterior ridge. The buccally enlarged osteotomy broadens the vision of practitioners and facilitates access of instruments in the sinus. Compared with the traditional lateral approach of sinus lift, the proposed technique offers a more conservative treatment modality. A clinical study with sufficient subjects and long-term follow-up is needed to validate the potential and limitations of the proposed technique. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of alteration on speech articulation of adult patients between Hawley retainers and vacuum-formed retainers by an objective acoustic analysis of vowels and voiceless fricatives. Materials and Methods: Twenty adults, aged 19.0-29.0 years, who had just finished active orthodontic treatment were included in this study. They were divided into a Hawley retainer group and a vacuum-formed retainer group by sortation randomization method. The assessment of speech sounds was performed objectively using acoustic analysis before and after retainer application at the following time points: before wearing (T0), immediately after wearing (T1), and at 24 hours (T2), 1 week (T3), 1 month (T4), and 3 months (T5). Results: The production of /з:/, /i:/, /f/, /θ/, /s/, and /∫/ sounds for the Hawley retainer group and /i:/, /θ/, /s/, and /∫/ sounds for the vacuum-formed retainer group showed severe speech impairment according to acoustic analysis ( P < .05). A comparison of the Hawley retainer group with the vacuum-formed retainer group revealed that the performance of /i:/, /f/, and /s/ sounds were significantly different ( P < .05). Conclusion: Although sound distortion could be found in both the Hawley retainer group and the vacuum-formed retainer group, changes in articulation were more obvious in the Hawley retainer group. [ABSTRACT FROM AUTHOR]

Intratissue topical medication is important for the treatment of cutaneous, mucosal or splanchnic diseases. However, penetrating surface barriers to providing adequate and controllable drug delivery while guaranteeing adhesion in bodily fluids remains challenging. Here, the predatory behavior of the blue-ringed octopus inspired us with a strategy to improve topical medication. For effective intratissue drug delivery, the active injection microneedles were prepared in a manner inspired by the teeth and venom secretion of blue-ringed octopus. With on demand release function guided by temperature-sensitive hydrophobic and shrinkage variations, these microneedles can supply adequate drug delivery at an early stage and then achieve the long-term release stage. Meanwhile, the bionic suction cups were developed to facilitate microneedles to stay firmly in place (>10 kilopascal) when wet. With wet bonding ability and multiple delivery mode, this microneedle patch achieved satisfactory efficacy, such as accelerating the ulcers' healing speed or halting early tumor progression.