Dental status and respiratory risk: a critical issue in burn patients

Major burns trigger systemic immune dysregulation and a hypermetabolic state, exacerbating susceptibility to infectious complications. Postoperative pneumonia remains one of the most severe complications, prolonging mechanical ventilation and compromising the vital prognosis. As the oral cavity acts as a reservoir for opportunistic pathogens, bacterial translocation to the lower respiratory tract is facilitated by repeated intubations and the prolonged immobilization of these patients.

This retrospective study, involving a cohort of 894 adults admitted to intensive care between 2015 and 2024, evaluates the association between preoperative dental status and the occurrence of pneumonia at 30 days. The objective was to determine whether simple clinical criteria (missing, mobile, or fractured teeth), identifiable during standard anesthetic examination, allow for the stratification of perioperative infectious risk.

The authors tested the hypothesis that poor dental status is an independent predictor of postoperative pneumonia and negatively impacts overall recovery, measured by the number of days alive and out of hospital or intensive care at 90 days. Given the impracticality of complex dental indices (DMFT, OHAT) in the context of severe burns, this research explores the validity of a rapid visual assessment as a risk management tool.

Study methodology

This retrospective cohort study was conducted between 2015 and 2024 within a tertiary university hospital center. It included 894 adult patients (≥ 19 years) admitted to the intensive care unit (ICU) for major burns. Inclusion criteria included a deep burn surface area ≥ 20% (≥ 10% for patients aged 65 and over), high-voltage electrical burns, or inhalation injuries.

Preoperative dental status assessment was performed by anaesthetists during systematic airway examination prior to induction of general anaesthesia. Patients were classified into two distinct groups:

• Favourable dental status group.
• Unfavourable dental status group: defined by the presence of at least two missing teeth (including complete edentulism), mobile teeth or fractured teeth.

The primary endpoint was the occurrence of postoperative pneumonia within 30 days, diagnosed according to specific clinical criteria (radiographic infiltrates, sepsis, or changes in sputum). Secondary endpoints measured the number of days alive and out of the hospital and intensive care unit at 90 days. Statistical analysis was performed using a multivariate model to adjust for confounding variables (age, comorbidities, burn surface area, inhalation injury).

Incidence of postoperative pneumonia

Of the 894 adult patients admitted to intensive care units (ICU) for severe burns, 294 developed postoperative pneumonia within 30 days, representing an overall incidence of 32.9%. Preoperative dental status proved to be a major prognostic marker for this infectious complication.

• Unfavourable dental status: 47.7% incidence of pneumonia.
• Favourable dental status: 31.2% incidence of pneumonia.
• Statistical significance: p < 0.001.

Multivariate analysis identifies unfavorable dental status (defined by the presence of at least two missing, mobile, or fractured teeth) as an independent predictor of 30-day pneumonia risk, with an odds ratio (OR) of 1.681 (95% CI: 1.084–2.599; p = 0.018).

Impact on length of stay and recovery

Secondary results show that patients with poor oral health exhibit slower clinical recovery, with a significant reduction in the number of days alive and out of hospital and intensive care over a 90-day period.

The diagnosis of pneumonia was based on clinical criteria specific to burn patients, including the presence of new infiltrates, consolidation, or cavitation on chest radiography, associated with signs of sepsis or a change in sputum purulence.

Clinical analysis of results

This retrospective study conducted on 894 patients shows a clear correlation: an unfavorable preoperative dental status — defined by at least two missing, mobile, or fractured teeth — increases the risk of postoperative pneumonia in severely burned patients by 68% (OR 1.681). The 30-day pneumonia rate reaches 47.7% in patients with degraded dental status, compared to 31.2% for those with a favorable status. These results emphasize that the oral cavity constitutes a major reservoir of respiratory pathogens, whose translocation is facilitated by systemic immunosuppression induced by burns and repeated airway manipulations in intensive care.

Implications for recovery and limitations

The impact extends beyond simple pulmonary infection; patients with an unfavorable dental score benefit from significantly fewer hospital-free days (9 vs 22 days) and fewer days out of intensive care (65 vs 68 days) over a 90-day period. However, the study presents methodological limitations: its retrospective nature and the use of a simplified dental assessment by anesthesiologists, excluding an in-depth periodontology analysis or dental plaque measurement. Nevertheless, this simplification reinforces the clinical relevance of the criterion for rapid application in surgical emergency contexts.

Towards a systematic risk stratification

Although the link between oral health and pneumonia is documented in geriatrics and general intensive care, this study specifically confirms this risk in severely burned patients. It suggests that a rapid visual examination of the dentition during pre-anaesthetic assessment is a powerful and accessible tool for infectious risk stratification. For the practitioner, identifying these high-risk patients allows for the anticipation of increased respiratory monitoring and the consideration of reinforced oral hygiene protocols upon admission to critical care units.

In concrete terms, for the practitioner:

• Risk stratification: Use rapid visual inspection of the teeth (mobility, fractures) as a simple tool for predicting respiratory risk before any major surgery.
• Perioperative alert: A patient with significant tooth loss must benefit from enhanced pulmonary monitoring, as their risk of infectious complications is multiplied by 1.68.
• Hygiene in critical care: Raise awareness among your intensive care colleagues about the importance of oral sanitation to limit bacterial translocation to the respiratory tract during airway management.

Technical lexicon of the study

Unfavorable dental status: Evaluation criterion defined in this study by the presence of at least two missing teeth (including complete edentulism), mobile teeth, or fractured teeth during the preoperative examination.

Systemic immune dysregulation: Profound alteration of immune defense mechanisms following a major burn, increasing the patient's susceptibility to opportunistic infectious complications.

Postoperative pneumonia: Respiratory complication defined here by the association of at least two clinical criteria: new infiltrate or consolidation on chest X-ray, state of sepsis, or recent change in the abundance or purulence of sputum.

Bacterial translocation: Process of migration of opportunistic pathogens from the oral reservoir to the lower respiratory tract, a phenomenon facilitated by endotracheal intubation and prolonged immobilization in intensive care units.

Inhalation injury: Traumatic damage to the airways diagnosed by bronchoscopy and carboxyhemoglobin measurement, constituting a major risk factor for pulmonary complications in burn patients.

Hypermetabolic response: Intense systemic physiological reaction triggered by a severe burn, capable of exacerbating existing oral infections and compromising overall clinical outcomes by creating a persistent inflammatory environment.

Hospital-free/ICU-free days: Clinical recovery indicators measuring the number of days, over a 90-day postoperative period, during which the patient is alive and no longer hospitalized or admitted to an intensive care unit.

Information intended for healthcare professionals. This content may contain errors or truncated summaries. We recommend always verifying with the original source article. Delynov disclaims all responsibility regarding the use of this information. This document is not intended for patients or the general public.