Hot glue gun turned surgical tool can rebuild broken bones

When a bone is shattered or a tumor leaves a sizable void, surgeons have two broad choices: pack the space with graft (bone taken from the patient or a donor) or plug it with a synthetic scaffold that encourages new bone to grow. 

Custom 3D-printed implants have been a big advance, but they take time. Scanning, design, fabrication, and sterilization often take a week or more. That’s fine for planned procedures. It’s a problem when seconds count, like in trauma surgery.

A team led by Jung Seung Lee at Sungkyunkwan University, South Korea, asked a disarmingly simple question: what if the scaffold could be made on the spot, shaped by the surgeon in minutes, and still meet the biological requirements for bone regeneration? 

The answer looks a lot like something you’d find in a craft drawer: a hot glue gun – reengineered for the operating room – and a bioactive “glue” designed to become new bone.

Bone mineral meets glue gun

The cartridge inside their gun isn’t glue. It’s a blend of hydroxyapatite (HA) – the calcium-phosphate mineral that makes up about half of real bone by volume – and polycaprolactone (PCL), a biodegradable thermoplastic widely studied for medical use. 

HA brings osteoconductivity, meaning it’s the right mineral for bone cells to grow on. PCL brings melt-and-set workability and a gentle degradation profile over months to years, giving the body time to swap the scaffold for living bone.

Standard hot glue guns run well above 100 °C – too hot for tissue. The team modified the gun so the melt temperature sits near 60 °C, around the melting point of PCL.

That’s still warm, but brief, localized contact at that temperature is routinely managed in surgery (think electrocautery), and the material cools and hardens quickly once extruded. 

How it’s used in surgery

In their proof-of-concept, surgeons would debride and clean the defect, then “draw” with the gun, layering the HA–PCL filament directly into the void. 

Because the material extrudes as a thin bead and sets within seconds, the surgeon can sculpt to fit the irregular geometry of real fractures – no waiting for a lab to print, ship, and sterilize a custom implant. 

If needed, the filament can be pre-loaded with drugs. The group demonstrated vancomycin and gentamicin embedded in the material, releasing slowly over weeks to bathe the surgical site and help suppress infection.

What happened in living bone

To test whether the on-demand scaffold actually supports regeneration, the team created centimeter-long defects in rabbits’ femurs – a challenging gap size that doesn’t reliably heal on its own. 

After 12 weeks, the animals treated with the “glue gun” showed no separation at the bone-implant interface and no obvious adverse reactions. Quantitatively, bone volume within the defect was more than twice that of controls filled with traditional bone cement. 

That’s an important point: standard cements (like PMMA) are structural fillers but biologically inert; they don’t invite bone to grow in and replace them. The HA–PCL composite, by contrast, is designed to be colonized by bone cells and resorbed over time.

Repairing bones with a glue gun

Orthopedic infections can turn a routine repair into a months-long ordeal. Because the scaffold is heat-molded at the point of care, the team could simply mix antibiotics into the filament beforehand. 

In their tests, vancomycin and gentamicin loaded into the composite leached out gradually and directly into the defect bed. This delivery path avoids high systemic drug levels and targets the microbes where they live – on hardware and within the healing bone.

Speed and fit are the headline advantages. In trauma, tumor surgery, or revision cases with irregular voids, being able to fill and contour in minutes is a big deal.

The material choice is sensible: HA for bioactivity, PCL for processability and a degradation timetable that lines up with bone remodeling.

Remaining challenges and questions

There are open questions before a craft-gun-turned-medical-tool goes mainstream. Heat exposure must be managed carefully near delicate structures.

Mechanical strength is likely adequate for non- or partial-load-bearing zones, but long-bone defects under high stress may still require plates, rods, or staged reconstructions. 

Surgeons will want more data on long-term remodeling: does the scaffold resorb at a rate that matches new bone formation, and what happens in larger animals and humans? 

And then there’s regulation – turning commodity hardware into a sterile medical device, with validated temperatures, flow rates, cartridges, and cleaning protocols, is its own development path.

It’s a fair challenge: imaging and printing are getting faster, and customized implants will keep improving. The right answer may be to use printing for planned, complex reconstructions, and keep a bone-safe “glue gun” on the back table for the cases that can’t wait.

A simple tool for surgery

What makes this approach intriguing is less the gadget itself and more the workflow it enables.

In one trip to the OR, a surgeon could clear debris, rebuild a defect to fit, deliver local antibiotics, and leave behind a scaffold the body recognizes – all without couriering scans or scheduling a second procedure.

The materials are inexpensive and familiar, and the technique builds on skills orthopedic and maxillofacial surgeons already have.

There’s also room to grow. The same platform could accept filaments tuned for different jobs – stiffer or more porous, faster or slower to resorb, with growth factors, even with living cells for future applications. 

The future of surgical glue guns

As faster point-of-care imaging and planning tools enter the OR, “draw-to-fit” reconstruction could be guided by intraoperative scans, blending the best of custom design with the immediacy of a handheld device.

For now, the takeaway is straightforward. By lowering the melt temperature and swapping craft glue for a bone-friendly composite, researchers turned a ubiquitous tool into a surgical instrument that can fill irregular defects, support bone growth, and deliver local antibiotics – all in minutes.

In emergencies and hard-to-plan repairs, that kind of speed could be the difference between patching a void and truly regenerating bone.

The study is published in the journal Device.

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