Intraoperative Cytology as a Diagnostic Tool for Pulpal Disease and Its Implications for Vital Pulp Therapy: An Exploratory Study

To characterise the cytological features of healthy and inflamed dental pulp and evaluate the feasibility of intraoperative brush cytology as a rapid diagnostic tool for pulpal disease.

This exploratory feasibility study included 40 pulp samples: 20 from healthy teeth extracted for non-pathological reasons and 20 from teeth diagnosed with pulpitis. Healthy samples were obtained from extracted teeth, whereas inflamed samples were collected intraoperatively during pulpotomy or root canal treatment. Cytological specimens were obtained using a sterile microbrush, stained with Diff-Quik and digitally evaluated by 2 blinded pathologists. Healthy samples were also examined histologically using haematoxylin and eosin staining. Cytomorphological findings were used to establish a 4-grade cytological classification. Interobserver reproducibility and exploratory associations between cytological score, treatment, spontaneous pain and sensibility-test response were evaluated.

Healthy pulp showed a consistent cytological pattern characterised by scattered nuclei on a slightly granular background without inflammatory infiltrates, consistent with histological findings. Inflamed specimens exhibited progressive cytomorphological changes ranging from predominantly haemorrhagic smears with few inflammatory cells to severe inflammatory infiltrates, degenerative changes, microorganisms and non-viable smears. Interobserver agreement for the proposed classification was excellent (95% exact agreement; weighted Cohen's κ = 0.962). Cytological scores were associated with treatment type, spontaneous pain (both P < .001) and sensibility-test response (Spearman's ρ = 0.820; P < .001), although these findings should be considered exploratory.

Intraoperative brush cytology provides reproducible cytomorphological information and is a feasible approach for chairside assessment of pulpal inflammation. The proposed classification may complement conventional clinical evaluation and support treatment decision-making in biologically based endodontics. Further studies are required to validate the classification and determine its diagnostic and prognostic value.