Hematomas Caused By Dental Injections and How to Avoid Them
Getting an injection at the dentist’s office is often necessary for numbing during procedures. But injections come with certain risks, including hematomas. A hematoma is a pooling of blood under the skin that causes bruising and swelling.
Hematomas from dental injections are usually minor and resolve on their own. But they can alarm patients if the cause is unclear. Understanding what causes injection-related hematomas and how to prevent them can help put patients at ease.
Causes of Injection Hematomas
There are a few ways that dental injections can lead to hematoma formation:
Striking a Blood Vessel
If the needle pierces a small blood vessel during injection, bleeding can occur under the skin at the site. This blood pooling forms the hematoma. Small vessels may not be visible and are easily struck, especially around the mouth where there is dense vasculature.
Exiting a Vein
The needle may properly enter a muscle without hitting a vessel. But upon injection or withdrawal, it could slip out and puncture a nearby vein. Again, bleeding results in a bruise if blood leaks under the skin.
Applying Excessive Pressure
Heavy-handed injection technique can puncture tiny capillaries. This causes minor blood leakage. Plus, excess pressure tends to damage tissue and spread injected fluid over a wider area under the skin. A larger bleed exacerbates bruising.
Injecting Too Much Solution
Overfilling the target area with anesthetic widens tissue spaces. More space allows more blood to accumulate after vessel damage. Using more solution than necessary increases hematoma risk.
Pulling the Plunger Mid-Injection
Suction effect from pulling back the plunger during injection can draw blood into the syringe. Then when the plunger is pushed again, blood exits into surrounding tissues. This deposits blood where it can pool and cause a bruise.
Risk Factors
Certain patient health factors may increase risk of developing a hematoma from dental injections:
Advanced Age
Elderly patients have more fragile veins and thinner skin. Their circulation is also slower, allowing blood to accumulate under the skin after even minor vessel injury.
Medications or Herbs
Blood thinners, anticoagulants, NSAIDs, garlic, ginkgo, and vitamin E all reduce blood clotting. This makes patients more prone to bleeding complications from injections.
Genetic Clotting Disorders
Disorders like hemophilia and von Willebrand disease impair the blood clotting process. Patients with these conditions are at very high risk of hematomas from any needle puncture.
Previous Botox Injections
Dermal fillers like Botox weaken tissues and blood vessels where injected. The same sites can then bleed more easily when punctured again for dental anesthesia delivery.
Location Matters
Where the injection is given also influences hematoma likelihood. The mouth area's dense vascular network raises risk compared to most areas of the body. Specific sites also tend to bleed more readily:
Palate
Injecting the palate is complicated by many delicate surface blood vessels and thin oral mucosal tissues. Patients commonly develop hematomas in the palate from dental anesthesia.
Tongue
The tongue contains interlacing blood vessels throughout its muscle structure. Poking just a short distance into the tongue often nicks a vessel, resulting in tongue hematomas.
Floor of Mouth
A large vein runs through the floor of mouth bilaterally. Injecting the left or right side risks piercing this sublingual vein or associated branches.
Under Tongue
The underside of tongue is filled with a fine vascular network known as the plexus of ranine veins. Injecting this area has an elevated risk of bleeding complications.
Treating Injection Hematomas
Most dental injection hematomas need no special treatment and resolve on their own within a week or two. But patients can aid healing with a few simple steps:
Cold Compress
Applying a cold pack or cooled spoon to the area minimizes swelling. Cold causes local vasoconstriction to slow bleeding under the skin.
Gentle Massage
Light massage helps dissipate pooled blood by moving it back into circulation. But vigorous rubbing could worsen tissue inflammation.
Pain Medication
Over-the-counter analgesics like acetaminophen relieve discomfort associated with the bruise. Avoid blood thinners like aspirin and ibuprofen.
Soft Diet
Sticking to cool, smooth foods for a few days prevents trauma to a healing hematoma. Hard, crunchy foods may aggravate the area.
Oral Hygiene
Continue gently brushing the affected part of the mouth. Proper hygiene promotes healing and prevents secondary infection.
If home care doesn’t resolve symptoms in 1-2 weeks, oral surgery may be needed to drain collected blood. But this is rarely necessary with injection site hematomas.
Preventing Dental Injection Hematomas
While some hematomas are inevitable, certain injection techniques help reduce their frequency and severity:
Proper Patient Screening
Review medical history to identify patients on blood thinners or with clotting disorders. Adjust treatment approach in these high-risk cases.
Sharp Needle Bevel
Using a sharp needle allows smooth, clean entry into tissues without excessive tearing. Dull needles crush tissues and damage more vessels.
Fine Needle Gauge
Thinner needles, like 30 gauge, separate tissues neatly rather than forcibly pushing them aside. This better avoids vascular injury.
Slow Injection Speed
Inject solution gradually over 15-30 seconds. Rapid bolus delivery maximizes tissue pressures, increasing hematoma risk.
Aspirating Before Injecting
Pulling back on the plunger checks for blood drawback in the syringe. Blood indicates the needle tip lies within a vessel and should be repositioned.
Minimum Effective Dose
Inject only enough anesthetic for the planned procedure. More solution distends tissues and allows larger hematomas to develop.
Pulling Needle Straight Out
Withdrawing the needle along its insertion path prevents angling into adjacent vessels. This maintains clean entry and exit wounds.
Applying Pressure After
Have the patient gently bite on gauze post-injection. Applying pressure for 2-5 minutes seals the puncture site to prevent ongoing bleeding.
When to Worry About a Hematoma
Though typically harmless, dental injection hematomas warrant medical referral in certain scenarios:
Persistent Bleeding
If bleeding at the site continues beyond 20 minutes of applied pressure, further treatment is needed to clot the disrupted vessel.
Severe Swelling
Quickly enlarging hematomas that involve extensive bruising and edema suggest a major vessel injury requiring repair.
Impaired Breathing
Large lingual hematomas can obstruct breathing by blocking the airway. This constitutes a medical emergency requiring urgent care.
Numbness Beyond Anesthetized Area
Expanding numbness implies
FAQs
What causes a hematoma after a dental injection?
Striking a blood vessel, exiting a vein, applying excessive pressure, injecting too much anesthetic, or pulling the plunger mid-injection can all cause bleeding and bruising under the skin.
Where are hematomas most common after dental injections?
The palate, tongue, floor of the mouth, and under the tongue are high-risk injection sites prone to developing hematomas due to the dense vasculature.
How can dental injection hematomas be prevented?
Careful injection technique using sharp, fine needles; proper patient screening; aspiration before injecting; and applying pressure after can all help prevent hematomas.
How are hematomas treated after dental injections?
Most resolve on their own using cold compresses, gentle massage, pain medication, soft foods, and good oral hygiene. Severe cases may require surgical drainage.
When should you seek medical care for an injection hematoma?
See a doctor for persistent bleeding, rapidly expanding swelling, breathing impairment, or numbness beyond the injection site, which could indicate serious vessel injury.
Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.
Add Comment