Endodontics · patient case with 2 questions
Third Trimester, Woken by Toothache
Patient: 29-year-old female, 33 weeks pregnant
Chief Complaint: “The tooth woke me up at two in the morning. It throbs.”
Background: First pregnancy, uncomplicated. Prenatal care up to date, taking a prenatal vitamin with folic acid and iron.
Medications: Prenatal multivitamin
Vital Signs: BP 116/70 mmHg · HR 88 bpm · RR 18 · T 98.4°F
Findings: Tooth #19 has a large MOD amalgam. Lingering pain to cold, spontaneous night pain, TENDER TO PALPATION in the buccal vestibule. No apical radiolucency, no swelling, no mobility.
Question 1
What is the most appropriate immediate management?
Show answer and explanation
Correct answer: A. Remove the MOD restoration, excavate the caries and place a sedative filling
- A. CORRECT. Removing the failing restoration, excavating caries and placing a SEDATIVE (zinc oxide-eugenol) dressing removes the source of pulpal irritation, relieves symptoms and is a short, well-tolerated procedure. Pain and infection are themselves risks in pregnancy — untreated dental pain drives stress hormones and poor nutrition — and the second trimester through early third trimester is a safe window for necessary care. Definitive treatment can follow once she is comfortable.
- B. Deferring treatment of ACTIVE pulpal pain until after delivery is not acceptable. There is broad professional consensus that necessary dental treatment should not be postponed because of pregnancy.
- C. Analgesics alone do not address the cause, and the analgesic options in the third trimester are restricted — which makes definitive source control more important, not less.
- D. A full pulpectomy is defensible if the pulp is diagnosed irreversibly inflamed, but it is a long appointment in a patient who cannot lie supine comfortably. The sedative dressing is the appropriate first step; supine hypotensive syndrome from caval compression means she should be positioned with a left-lateral tilt and appointments kept short.
Note: ⚑ Third-trimester positioning: place a wedge under the RIGHT hip to tilt her to the LEFT, displacing the gravid uterus off the inferior vena cava. If she becomes lightheaded and pale while reclined, roll her fully onto her left side.
Question 2
Which of the following would NOT increase the risk of an orofacial cleft in her baby?
Show answer and explanation
Correct answer: D. Iron deficiency
- A. Tobacco IS a recognised risk. Maternal smoking raises the risk of orofacial clefting roughly 1.3 to 1.5 fold in a dose-dependent way, and also causes low birth weight and preterm birth.
- B. Alcohol IS a recognised risk. Fetal alcohol spectrum disorder includes midface hypoplasia, a smooth philtrum, a thin upper lip, short palpebral fissures and an increased incidence of clefting. There is no established safe threshold.
- C. Folic acid deficiency IS a recognised risk. Periconceptional folate supplementation reduces both neural tube defects and orofacial clefts, which is why 400 µg daily is recommended before conception and through the first trimester.
- D. CORRECT — this is the EXCEPTION. IRON DEFICIENCY causes maternal anaemia, fatigue, low birth weight and preterm delivery, but it is NOT a recognised cause of cleft lip or palate. Iron is essential for oxygen transport, not for the fusion of the facial processes.
Note: Fusion of the lip is complete by about week 6 and of the palate by about week 12 — so cleft risk is determined in the FIRST trimester, often before pregnancy is recognised. That is the entire rationale for preconception folate.