Should we do a PSA or Infiltration?

Check out Jessica Atkinson in this video case study where she has to decide whether or not to do a PSA or Local Infiltration.  

When performing periodontal therapy, particularly in the maxillary molar region, the choice between using an infiltration injection or a posterior superior alveolar (PSA) injection can have significant implications for patient comfort and treatment effectiveness. An infiltration injection, where the anesthetic is deposited near the apex of the tooth, is often preferred for its precision and lower risk of complications. The anesthetic is delivered in close proximity to the targeted area, which allows for more focused pain management without affecting larger regions of the oral cavity. This technique is especially useful when treating a single tooth or a localized area, minimizing the risk of hematoma formation, which is more commonly associated with PSA injections.

On the other hand, a PSA injection is used to anesthetize the maxillary molars, targeting the posterior superior alveolar nerve. This approach allows for more comprehensive anesthesia, typically covering multiple teeth simultaneously. However, this method has an increased risk of complications, such as hematoma due to the proximity of the pterygoid plexus of veins and the maxillary artery. While PSA injections can be more efficient for treating multiple molars or performing extensive periodontal procedures, they require careful technique and an experienced hand to avoid complications. Additionally, PSA anesthesia may lead to a more pronounced loss of sensation in larger areas of the cheek and upper jaw, which some patients find uncomfortable during and after treatment.

Research comparing the effectiveness of these two injection techniques in periodontal therapy has shown that infiltration injections provide adequate anesthesia for most periodontal procedures involving maxillary teeth, especially when only one or two teeth are being treated. According to Meechan (2005), infiltration injections using articaine have been shown to have superior efficacy in anesthetizing maxillary molars compared to traditional lidocaine solutions used in PSA blocks, making them a preferred choice for many clinicians depending on the patient’s needs and the scope of the treatment plan (Meechan, J. G. (2005). 

Meechan JG. The use of the mandibular infiltration anesthetic technique in adults. J Am Dent Assoc. 2011 Sep;142 Suppl 3:19S-24S. doi: 10.14219/jada.archive.2011.0343. PMID: 21881058.