Results of a new study, which assessed pain following root canal surgery, suggested females with and without anemia had similar levels of pain 24 hours after surgery, but those without anemia experienced a greater pain reduction after 48 and 72 hours.

Anemia is a risk factor of post-endodontic pain, and so the investigators of the study stressed that diagnosing and treating anemia can improve a patient’s quality of care. Previous research had examined the association of and anemia and pain post-treatment—for example, an earlier study found that patients with sickle cell anemia experience severe pain during vascular obstruction.2

The new descriptive cross-sectional study wanted to explore the association between iron deficiency anemia and the level of pain severity following root canal treatment. Specifically, the team wanted to examine the pain levels of women with and without iron deficiency anemia.1

Led by Maryam Kazemipoor, MSc, DDs, of the department of endodontics at Shahid Sadoughi University of Medical Sciences, Yazd, Iran, the investigators gathered their participant sample (n = 60), aged 18 – 54 years. Participants had previously received treatment at a specialized clinic in Yazard and were diagnosed with either reversible pulpitis with or without acute periapical periodontitis, pulp necrosis with acute periapical periodontitis, and pulp necrosis with acute periapical abscess in their lower posterior teeth.

“Surprisingly, the incidence of postendodontic pain in relation to iron deficiency anemia has not been studied until now,” wrote the investigators. “The primary objective of this study was to evaluate both the incidence and intensity of pain in patients with and without iron deficiency anemia undergoing root canal treatment.”

Half of the women had hemoglobin levels above 13 (indicating no iron deficiency anemia) and the other half had hemoglobin levels below 11 (indicating iron deficiency anemia). The mean hemoglobin level for the entire study group was between 7.70 and 14.90.

The investigators also examined tooth type and 16.9% had mandibular first premolars, 27.1% had mandibular second premolars, 35.6% had mandibular first molars, and 20.3% had mandibular second molars. As for pupal status, 36.7% had necrotic teeth and 63.3% had irreversible pulpitis. For the periapical status, 41.7% patients had acute periapical periodontitis, 1.7% had acute periapical abscess, and 56.7% had normal periapical status.

All patients had a root canal procedure. Afterward, patients had 400 mg of ibuprofen every 8 hours. The investigators recorded the level of pain after 24, 48, and 72 hours. They then analyzed the data using SPSS software, a 2-way analysis of variance, a paired t-test, and Pearson correlation coefficient.

The investigators found the incidence of pain in both the anemia and non-anemia group was 80%. For just the people with iron deficiency anemia, this number was 71.66%, and for people without iron deficiency anemia, it was 61.12%.

Patients with anemia had an incidence of pain of 100% at 24 hours, 96.67% at 48 hours, and 50% at 72 hours. Meanwhile patients without anemia had an incidence of pain of 100% at 24 hours, 53.34% at 48 hours, and 40% at 72 hours. Thus, patients with anemia had more severe pain 2 – 3 days later than the patients without anemia.

“The results revealed that the prevalence of pretreatment endodontic pain was high (28%) but dropped moderately within 1 day (24%) and reached the minimal level in 7 days (14%),” the team wrote. “Also, the severity of posttreatment endodontic pain was moderate but decreased within 1 day following treatment and reached a minimal level in 7 days.”

After the t-test, there was no significant differences in preoperative pain (P = .643) and postoperative pain at 24 hours (P = .093).

Though, when comparing anemic and non-anemic patients, the team noted a significant difference in postoperative pain at 48 hours (P = .004) and 72 hours (P = .034).

For patients without anemia, the mean difference (-0.73) between increasing pain before treatment and 24 hours post-treatment was not statistically significant (P = .118). Though it was statistically significant difference for the iron deficiency anemia group (P = .007).

The investigators found there was a statistically significant mean difference in pain reduction before treatment and after 48 hours (P = .003). For the anemia group, there was no significant difference between the pain before treatment and after 48 hours (P = .163).

Finally, for 72 hours, there was a statistical mean difference in pain reduction before treatment and after 3 days for the non-anemic group (P = .000). For the anemic group, there was a significant mean difference between the pain before the treatment and after 72 hours (P = .000).

Age ultimately had no effect on mean pain, and neither did the type of teeth as there was no significant difference found.

The investigators found the condition of the pulp (vitality and necrosis) in the mandibular premolars and molars had a significant effect on pain mean difference before and after treatment.

Patients reported greater pain in necrotic teeth after 24 hours than people with irreversible pulpitis. When assessing pain 48 hours and 72 hours after the procedure, patients reported less pain in both necrotic and irreversible pulpitis teeth, but pain in the irreversible pulpitis had lowered more.

“In this study, it was observed that the mean pain intensity before and after treatment was higher in anemic women compared to non‐anemic ones, with significant differences noted after 48 and 72 [hours]” the team wrote. “However, while the mean pain score after 72 [hours] may show statistical significance between anemic and non‐anemic patients, it may not hold clinical significance.”

References

1. ^{Kazemipoor, M., Moradi, H.,Mokhtari, F., & Kheirollahi, K. (2023). Assessing the occurrence and severity of pre‐ and postendodontic pain in anemic and healthy female patients. Clinical and Experimental Dental Research, 1–7. https://doi.org/10.1002/cre2.799}
2. ^{Kawar, N., Alrayyes, S., & Aljewari, H. (2018). Sickle cell disease: An overview of orofacial and dental manifestations. Disease‐a‐Month, 64(6), 290–295.}