Transient neonatal exposure to hyperoxia, an experimental model of preterm birth, leads to skeletal muscle atrophy and fiber type switching.

Individuals born preterm show reduced exercise capacity and increased risk for pulmonary and cardiovascular diseases, but the impact of preterm birth on skeletal muscle, an inherently critical part of cardiorespiratory fitness, remains unknown. We evaluated the impacts of preterm birth-related conditions on the development, growth, and function of skeletal muscle using a recognized preclinical rodent model in which newborn rats are exposed to 80% oxygen from days 3 to 10 of life. We analyzed different hindlimb muscles of male and female rats at 10 days (neonatal), 4 weeks (juvenile), and 16 weeks (young adults). Neonatal high oxygen exposure increased the generation of reactive oxygen species (ROS) and the signs of inflammation in skeletal muscles, which was associated with muscle fiber atrophy, fiber type shifting (reduced proportion of type I slow fibers and increased proportion of type IIb fast-fatigable fibers), and impairment in muscle function. These effects were maintained until adulthood. Fast-twitch muscles were more vulnerable to the effects of hyperoxia than slow-twitch muscles. Male rats, which expressed lower antioxidant defenses, were more susceptible than females to oxygen-induced myopathy. Overall, preterm birth-related conditions have long-lasting effects on the composition, morphology, and function of skeletal muscles; and these effects are sex-specific. Oxygen-induced changes in skeletal muscles could contribute to the reduced exercise capacity and to increased risk of diseases of preterm born individuals.

Medication-related osteonecrosis of the jaw: An institution's experience.

OBJECTIVES: This study aimed to evaluate and report the outcomes associated with the management of patients who were treated surgically for medication-related osteonecrosis of the jaw (MRONJ).Methods: Demographic and medical profiles of patients with a diagnosis of MRONJ were created. The type of surgical treatment, complications, and treatment outcomes were identified.Results: Twenty-one patients with an average age of 68.42 years (range 40-90 years) were included. Nineteen patients had only mandible involvement, one patient had only maxilla involvement, and one patient had both mandible and maxilla involvement. Thirteen patients underwent marginal resections. Eight patients underwent segmental resection of the mandible with immediate reconstruction. Nineteen patients healed without any complications. Two patients who had undergone segmental resection of the mandible experienced postoperative complications and needed a second surgery to achieve primary closure.Discussion: Advanced MRONJ can effectively be treated with resective surgery in combination with medical treatment.

The Effect of Coded Healing Abutments on Treatment Duration and Clinical Outcome: A Randomized Controlled Clinical Trial Comparing Encode and Conventional Impression Protocols.

PURPOSE: To compare the Encode impression protocol (Biomet 3i) with the conventional impression protocol in terms of treatment duration, clinical accuracy, and outcome up to the first postplacement review of single-implant crowns. MATERIALS AND METHODS: A total of 45 implants were included in this study. The implants were randomly allocated to the Encode group (23 implants) or the conventional group (22 implants). At the time of surgery, all implants received two-piece Encode healing abutments. The implants were restored 3 months after insertion. In the conventional protocol, open-tray implant-level impressions were taken and the implants were restored with prefabricated abutments and porcelain-fused-to-metal (PFM) crowns. For the implants in the Encode group, closed-tray impressions of the healing abutments were taken. The generated casts were sent to the Biomet 3i scanning/milling center for custom abutment manufacturing on which PFM crowns were fabricated. Treatment duration (laboratory and clinical), clinical accuracy of occlusal and proximal contacts, and outcome (esthetics, patient satisfaction, and crown contour) were evaluated with the aid of a series of questionnaires. RESULTS: The Encode protocol required significantly less laboratory time (18 minutes) than the conventional protocol for adjustment of the abutments. The impression pour time, time for the laboratory to return the crown, time for crown insertion at the final appointment, and total clinical time for crown insertion did not differ significantly between the two protocols. Likewise, clinical accuracy, esthetics, and patient satisfaction were similar for the two protocols. CONCLUSION: The two protocols were clinically comparable. The Encode protocol is advantageous in reducing the laboratory time before crown fabrication.