Reaction of rat pulp tissue to Carisolv ‘new gel’—-A histocytological evaluation

Evaluation and comparison of cytotoxicity and bioactivity of chemomechanical caries removal agents on stem cells from human exfoliated deciduous teeth

AIM

To investigate and compare the cytotoxicity and bioactivity of CMCR agents on stem cells derived from exfoliated deciduous teeth.

METHODOLOGY

MTT assay, flow cytometry, Alizarin Red staining and scratch assay were used to assess the cellular viability, apoptosis, calcium matrix deposits and cell migration, respectively. The gene expression of ALP and BMP-2 was measured with RT-PCR. One-way ANOVA and Bonferroni post-test was used for statistical analysis.

RESULTS

0.5% Carisolv showed highest cell proliferation and calcium matrix formation, whereas 0.5% Papacarie reported the highest% live cells and cell migration. The highest mRNA expression of ALP and BMP-2 was reported in SHEDs cultured in 0.5% Papacarie (after 72 h incubation) and 0.5% Carisolv (after 24 h incubation), respectively.

CONCLUSION

CMCR agents are biocompatible and bioactive when cultured in stem cells derived from exfoliated primary teeth.

Current update of chemomechanical caries removal methods

Chemomechanical caries removal is an excellent method for minimally invasive caries excavation, and the removal agents are either sodium hypochlorite (NaOCl)- or enzyme-based. The NaOCl-based agents include GK-101, GK-101E (Caridex) and Carisolv, and the enzyme-based agents include Papacarie and the experimental material, Biosolv. This review outlines the changes in chemomechanical caries removal methods and focuses on recently published laboratory and clinical studies. The historical development, mechanism of action, excavation time and biological effects on pulp and dental hard tissues are described. Based on existing evidence, the currently available chemomechanical caries removal methods are viable alternatives to conventional rotary instrument methods. Chemomechanical methods could be extremely useful in very anxious, disabled and paediatric patients. It does seem some of these agents would still benefit from quicker excavation times in order to achieve more universal acceptance. However, as a means of conserving the caries-affected dentine, chemomechanical caries removal is possibly much more successful than conventional rotary instrumentation.

Clinical evaluation of a chemomechanical method for caries removal in children and adolescents

OBJECTIVE

The purpose of this study was to make a clinical comparison of the chemomechanical method for caries removal and the conventional rotary instruments technique when used in children and adolescents.

MATERIAL AND METHODS

The study comprised 120 patients aged 3-17 years randomized into two groups: caries were removed chemomechanically in 60 patients and 60 patients received conventional treatment with rotary instruments. The outcome variables were: clinically complete caries removal, pain during caries removal, need for local anesthesia, treatment time, preferences of patients, and clinical success of the restorations during the 12-month evaluation period.

RESULTS

Complete caries removal was achieved in 92% of chemomechanically treated teeth and in all teeth treated with rotary instruments (p>0.05). The chemomechanical method significantly reduced the need for local anesthesia (p<0.001). Eighty-five percent of patients treated with Carisolv and 47% treated with rotary instruments were satisfied with the treatment (p<0.05). The mean time for chemomechanical caries removal was 11.2 ± 3.3 min and 5.2 ± 2.8 min for caries removal with rotary instruments (p<0.001). At the end of the 12-month evaluation period, there was no observed influence of the caries removal method on the survival of the restorations.

CONCLUSIONS

The chemomechanical caries removal technique is an adequate alternative to the conventional rotary instruments method and is advantageous in pediatric dentistry.

Rat molar teeth as a study model for direct pulp capping research in dentistry

The aim of this review is to evaluate the suitability of rat molar teeth in preclinical evaluation of medical devices for direct pulp capping. The ISO standard 7405 states clearly that only non-rodent mammals are suitable species for animal research in dentistry. Furthermore, without clear justification a considerable number of researchers previously rejected results of animal experiments concerning preclinical evaluation of the biocompatibility of dental materials undertaken in rat molar teeth. However, in the past 50 years about 70 studies have been published using rat molar teeth in order to evaluate direct pulp capping, pulpotomies and tissue reactions after pulp exposure. Numerous studies showed that the healing of rat molar pulp tissue after direct pulp capping is histologically comparable with humans and other animal species pulp tissue. Rat molar teeth, including pulp tissue, can be seen anatomically, histologically, biologically, and physiologically as miniature human molar teeth. Hence, the essential biological reactions of the pulp tissue and the interaction during the different stages of wound healing of rat molar teeth are comparable with that of other mammals. Rat molar teeth are a valid study model in order to provide valuable data concerning pulp tissue reaction after direct pulp capping and related questions in dentistry. Therefore, the use of rats may significantly reduce the number of currently used higher animals in research. Tests in higher developed animals should be limited to experiments which clarify inconsistent results. However, some technical difficulties, like the small size of rat molar teeth must be dealt with before undertaking any research.