# Pulpitis as a microbial disease: single-cell insights into host responses and diagnostic biomarkers for vital pulp therapy

## TL;DR

This paper explores how microbes and host cells interact in pulpitis, identifying potential biomarkers for better diagnosis and treatment of dental pulp inflammation.

## Contribution

The paper integrates single-cell transcriptomic evidence to reveal infection-specific responses of dental pulp stem cells and identifies microbial and host-derived biomarkers for pulpitis.

## Key findings

- Distinct microorganisms in pulpitis induce diverse inflammatory processes in dental pulp.
- Dental pulp stem cells show infection-specific transcriptional responses linked to inflammation severity.
- Microbial and host biomarkers consistently appear across studies and are validated by single-cell analyses.

## Abstract

Pulpitis is a common dental disease driven by complex microbial infections, yet its microbial origins, diversity, and pathogenic mechanisms remain incompletely understood. A major clinical challenge is the absence of objective biological criteria to assess the severity and reversibility of pulpal inflammation, which is essential for decision-making in vital pulp therapy (VPT).

This review aims to synthesize current evidence on the microbial landscape of pulpitis and to explore microbial- and host-derived biomarkers that may enable objective assessment of inflammation severity and support precision VPT.

We comprehensively reviewed microorganisms implicated in pulpitis and their distinct virulence mechanisms underlying inflammatory responses and tissue damage. Particular emphasis was placed on host responses of dental pulp stem cells (DPSCs) to different microbial infections. Biomarker candidates reported across multiple studies were summarized, and single-cell transcriptomic evidence was integrated to validate microbe-specific DPSC responses.

Distinct microorganisms associated with pulpitis exhibit heterogeneous virulence strategies, inducing diverse inflammatory and degenerative processes within the dental pulp. DPSCs display infection-specific transcriptional responses, revealing molecular signatures linked to inflammation severity and tissue repair potential. Emerging biomarkers derived from both microbial factors and host responses show consistency across studies, with single-cell analyses providing high-resolution validation of these microbe-specific patterns.

Microbial- and host-derived biomarkers hold significant translational potential for stratifying pulpitis severity, informing VPT decision-making, and predicting treatment prognosis. Integrating microbial characterization with host response profiling may advance objective diagnosis and personalized management of pulpitis.

The histopathology of pulpitis is fundamentally driven by the interaction between pathogens and host cells, particularly dental pulp stem cells (DPSCs), which respond by releasing a spectrum of enzymes and cytokines.Single-cell transcriptomic analyses further reveal that this interaction induces both homogeneous and heterogeneous responses across distinct DPSC subclusters.Our findings deepen our understanding of pulpitis pathogenesis and pave the way for improved therapeutic strategies for primary periodontal disease with secondary endodontic involvement.

The histopathology of pulpitis is fundamentally driven by the interaction between pathogens and host cells, particularly dental pulp stem cells (DPSCs), which respond by releasing a spectrum of enzymes and cytokines.

Single-cell transcriptomic analyses further reveal that this interaction induces both homogeneous and heterogeneous responses across distinct DPSC subclusters.

Our findings deepen our understanding of pulpitis pathogenesis and pave the way for improved therapeutic strategies for primary periodontal disease with secondary endodontic involvement.