Talk:Space medicine

Bone Healing Related to Bisphosphonates in Space

Background

Bisphosphonates are often prescribed for patients with low bone density such as for older females with osteoporosis. By impeding osteoclast function, bisphosphonates disrupt the process of bone remodeling, which impairs bone healing, particularly following invasive dental surgeries.

  • Patients on bisphosphonates are at risk for developing bisphosphonate-related osteonecrosis of the jaw (BRONJ)
  • The risk is more significant and common with IV bisphosphonates compared to oral bisphosphonates due to the increased dosage
  • BRONJ is more common in the posterior mandible, which is also more susceptible to bone resorption, so that area would be an efficient area to routinely assess during spaceflight (see ISS dental toolkit article for dental equipment details)
  • The posterior mandible has limited blood supply which is a reason for this area being more susceptible

Clinical Features

  • Bone exposure and necrosis, which is most commonly seen in the posterior mandible
  • Halitosis and inflammation of the necrotic area
  • Teeth may lose PDL (periodontal ligament) stability and become loose

Diagnosis

  • Diagnosis of MRONJ (medication-related necrosis) occurs when ecposed bone is evident for 8 weeks or more, and the patient in question has a medical history that includes bisphosphonates.


Treatment

  • Oral antibiotics, debridement, rinses
  • Patients on bisphosphonates should avoid dental extractions- DDS should request a medical consult with physician, especially for patients interested in spaceflight

Dental Fractures/Injury in Space

The ISS has technology and appliances that make it easy for an astronaut to accidentally bump into or injure their head or teeth.

  • Proclined incisors, especially maxillary incisors, have a more significant chance of injury which may be evident with a tooth fracture
  • Because spaceflight alters physiology and bone mass, fracture healing could possibly also be impacted.
  • A consequence of severe BMD loss is fracture risk

Treatment

  • Orthodontics to correct severely-proclined maxillary incisors
  • Padding over hard equipment in high-traffic areas on ISS to avoid potential injury
  • Mouthguards may be fabricated as a conservative approach to injury prevention


References: Moussa MS, Goldsmith M, Komarova SV. Craniofacial Bones and Teeth in Spacefarers: Systematic Review and Meta-analysis. JDR Clin Trans Res. 2023 Apr;8(2):113-122. doi: 10.1177/23800844221084985. Epub 2022 Mar 20. PMID: 35311413; PMCID: PMC10026165.