Preclinical Evaluation and Clinical Trial of Chlorhexidine Polymer Scaffold for Vital Pulp Therapy

Objective: To evaluate the preclinical effectiveness and clinical efficacy of chlorhexidine polymer scaffold for vital pulp therapy. Study design: Polymer scaffolds loaded with chlorhexidine were prepared by electrospinning. The scaffolds were evaluated using four different tests: i) The release of chlorhexidine from the polymer scaffold was evaluated by Fourier-transform infrared spectroscopy (FTIR); ii) Biocompatibility of chlorhexidine scaffold was tested by subcutaneous implantation in rabbits; iii) The scaffolds were implanted into human molars for further ex vivo histological evaluation; and iv) The clinical efficacy of the scaffold was evaluated as a pulp dressing following vital pulp therapy, in comparison with MTA (control) in a clinical trial of forty primary molar teeth in 34 children aged 6 to 8 years. Results: The scaffold was antimicrobial to Streptococcus mutans, Lactobacilli and other facultative anaerobes. Fourier-transform infrared spectroscopy confirmed the presence of chlorhexidine and polyvinyl alcohol in the scaffold. The histological evaluation of the subcutaneous tissue of rabbits and ex vivo human molars provided an acceptable biocompatibility response to scaffold. The clinical trial showed that the efficacy of chlorhexidine loaded scaffold was 90% and comparable to MTA. Conclusion: The scaffold met acceptable standards in all the four tests that were performed, including the clinical trial. A larger clinical trial with chlorhexidine scaffold in adult teeth may be necessary to prove its efficacy. The preliminary clinical trial results demonstrated that the scaffold was beneficial in saving primary teeth that required pulpotomy as a vital pulp therapy.

Vital pulp therapy; Polyvinyl alcohol; Mineral trioxide aggregate; Chlorhexidine

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