Thermal properties of polymethyl methacrylate vary depending on brand and type

Abstract

Polymethyl methacrylate (PMMA) is commonly used in orthopedic surgery and has several applications, most often for fixation of arthroplasty components. While its overall safety and tolerance are well described, less is known regarding the thermal properties of PMMA as it sets from a liquid to solid state, as well as the potential for osseous thermal necrosis. This study addresses potential variations in the setting time and maximum temperature of PMMA formulations in common use and explores the potential clinical implications of this variability. Seven commercially available formulations of PMMA that varied by brand and/or viscosity were obtained and prepared according to manufacturer's instructions. Peak temperature and duration were measured in controlled settings for each type and compared to previously described thresholds for thermal bone necrosis. Depuy SmartSet (HV), Zimmer Palacos R (HV), and Zimmer Palacos (LV) exceeded the 56°C threshold reported to potentially induce immediate osseous thermal necrosis. Additionally, Biomet Cobalt (MV) and Stryker Simplex P (MV) had lower peak temperatures but exceeded thermal necrosis thresholds due to curing duration. The lowest peak temperature was observed for Smith & Nephew Versabond (MV), which was significantly lower than all types except Depuy SmartSet (MV). Setting time was not significantly different among groups. There are significant differences in the thermal properties of PMMA formulations in current use. Selection of specific PMMA formulations represents an additional route of procedural optimization depending on the needs of the treating surgeon.

Tunable backbone-degradable robust tissue adhesives via in situ radical ring-opening polymerization

“…4 ). The tested temperatures lower than 45 °C were observed for the BDRA (MDO-HEMA) family, which were lower than that of Vetbond (~54 °C) and the thresholds for bone necrosis (56 °C) 41 . The tested temperatures of the BDRA (MDO-HEA) family ranging from 39 °C to 59 °C, were much lower than that of the acrylate homopolymer system (~100 °C), suggesting a lower damage probability of skin 42 .…”

Bone Cements Used in Vertebral Augmentation: A State-of-the-art Narrative Review

“… 17 A common complication associated with both Palacos R and Simplex P is tissue necrosis due to high exothermic releases. 18 The price of one Palacos R high viscosity cement is $60 per 40 g, whereas Simplex P costs $70 per 40 g. 19…”

“…Compared to acrylic PMMA cements, CPCs have a lower stiffness, less compressive strength and require significantly longer duration for complete curing to occur. 18 , 29 All of these factors have resulted in a limited amount of use of CPCs in vertebral augmentation.…”

“…They have unique attributes that are capable of self-hardening but are less commonly utilized than ABCs (Tables 4 and 5). [16][17][18][19] The setting reaction mechanisms of CPCs can be manipulated by changing the solubility of compounds and the entanglement of precipitated crystals causing the hardening. 5,20 These cement compounds have been shown to cure within 20 min but do not fully set for 12-48 h (Table 4).…”

Advances in materials used for minimally invasive treatment of vertebral compression fractures

“…Severe damage to neuromuscular structures have been reported; these can lead to serious complications including paralysis, bleeding, and even death. Bone necrosis and the resultant fiber healing caused by thermal injuries may weaken the interface between the implant and host bone; this may lead to aseptic loosening of the implant (Stoops et al, 2022). Appropriate temperature reduction can be achieved by decreasing the amount of PMMA powder; however, this tends to prolong setting times and reduce the viscosity of bone cement, thereby increasing intraoperative manipulation times and the risk of postoperative cement leakage.…”