Abstract: Hybrid orthodontic archwire designs are disclosed. Hybrid archwires may have bracket-archwire sections and interproximal archwire sections in which each section can vary in cross-section shape, size, and/or material properties. Bracket-archwire sections may be configured to promote torque control and may have rectangular cross-sections. Interproximal archwire sections may be configured to be bent into force-promoting loops and may have round cross sections. Each archwire section may be straight or bent into any shape. Hybrid archwires may have sliding sections and non-sliding sections. Non-sliding sections may have male connectors configured to prevent the archwire from sliding relative to the orthodontic brackets and/or may have cross-sectional shapes, sizes, or coatings that resist sliding relative to sliding sections. Sliding sections may have linear archwire segments. Hybrid archwires may have distal or posterior non-sliding sections and an intermediate anterior or medial sliding section.

Abstract: Systems and methods for fabricating indirect bonding trays are disclosed. Physical models of a patient's teeth can be created with non-functional placeholder brackets, impressions of which can be transferred to indirect bonding trays. This can create wells in which functional brackets can be placed into, reducing errors created from transferring functional brackets from the physical model onto the indirect bonding trays.

Abstract: A cracking furnace for cracking a hydrocarbon feed, the furnace including a firebox having a single radiant zone including, a first plurality of cracking coils each having a first shape arranged within the firebox. The radiant zone includes a second plurality of cracking coils each having a second shape arranged within the radiant zone. A burner section positioned below the first plurality cracking coils and below the second plurality of cracking coils. A convection section is positioned on top of the firebox configured to recover residual heat from the firebox.