Electrosurgery and wound healing: a review of the literature

Gingival Fibroblasts Are Sensitive to Oral Cell Lysates Indicated by Their IL11 Expression

Damaged cells that appear as a consequence of invasive dental procedures or in response to dental materials are supposed to release damage-associated signals. These damage-associated signals not only support tissue regeneration but might also contribute to unwanted fibrosis. The aim of this study was to identify a molecular target that reflects how fibroblasts respond to necrotic oral tissue cells. To simulate the cell damage, we prepared necrotic cell lysates by sonication of the osteocytic cell line IDG-SW3 and exposed them to gingival fibroblasts. RNAseq revealed a moderate increase in IL11 expression in the gingival fibroblasts, a pleiotropic cytokine involved in fibrosis and inflammation, and also in regeneration following trauma. Necrotic lysates of the human squamous carcinoma cell lines HSC2 and TR146, as well as of gingival fibroblasts, however, caused a robust increase in IL11 expression in the gingival fibroblasts. Consistently, immunoassay revealed significantly increased IL11 levels in the gingival fibroblasts when exposed to the respective lysates. Considering that IL11 is a TGF-β target gene, IL11 expression was partially blocked by SB431542, a TGF-β receptor type I kinase inhibitor. Moreover, lysates from the HSC2, TR146, and gingival fibroblasts caused a moderate smad2/3 nuclear translocation in the gingival fibroblasts. Taken together and based on IL11 expression, our findings show that fibroblasts are sensitive to damaged oral tissue cells.

Oral Cell Lysates Reduce the Inflammatory Response of Activated Macrophages

Necrotic cell damage occurs as a consequence of invasive dental procedures. Loss of membrane integrity being the hallmark of necrotic cells leads to the release of cytoplasmic and membranous components. Macrophages are predestined to respond to lysates originating from necrotic cells. Here, we implement necrotic lysates from human gingival fibroblasts, HSC2, and TR146 oral epithelial cell lines, and RAW264.7 macrophage cell lines to be tested for their potential to modulate the inflammatory response of macrophages. To this aim, necrotic cell lysates were prepared by sonication or freezing/thawing of the respective cell suspension. Necrotic cell lysates were tested for their potential to modulate the lipopolysaccharide (LPS)-induced expression of inflammatory cytokines using RAW264.7 macrophages as a bioassay. We show here that all necrotic cell lysates, independent of the origin and the preparation way, reduced the expression of IL1 and IL6 in LPS-induced RAW264.7 macrophages, most obviously shown for TR146 cells. This finding was supported in a bioassay when macrophages were exposed to poly (I:C) HMW, an agonist of TLR-3. Consistently, all necrotic lysates from gingival fibroblasts, HSC2, TR146, and RAW264.7 cells reduced the nuclear translocation of p65 in LPS-exposed macrophages. This screening approach supports the overall concept that necrotic cell lysates can modulate the inflammatory capacity of macrophages.

Laser-Assisted Depigmentation-An Introspection of the Science, Techniques, and Perceptions

BACKGROUND

Gingival hyperpigmentation is a major concern for a significant number of patients, as a relevant aesthetic or cosmetic need. Oral melanin pigmentation is considered to be multifactorial and could be related to physiological or even pathological reasons and can be the consequence of a variety of local or systemic factors. This pigmentation varies individually across races or age groups and is without any gender predilection. Evidence gleaned from literature is presented from case-control studies and from the authors' own research work in prospective, split-mouth, double-blinded, clinical trials comparing treatment modalities in effecting depigmentation.

METHODS

A systematic review of published articles, using suitable assay criteria, was carried out to formulate a consensus on laser-assisted modalities. A total of 295 published sources were subject to critical analysis and resulted in six papers that were subject to data scrutiny. Additionally, evidence is presented on clinical protocols and treatment outcomes.

RESULTS

Analysis of randomized clinical studies identified the use of two laser wavelength groups-near infrared diode and erbium group of mid-infrared lasers. Several areas of analysis were examined, and inconsistent degrees of significance were obtained to establish which laser group was optimal and if they were any better than scalpel depigmentation.

CONCLUSION

A definitive conclusion is wanting as studies with scientific and standardized protocols of evaluation are yet to provide a take on comparative assessments between different techniques of depigmentation.

Improved wound healing with a modified electrosurgical electrode

Previous studies comparing standard electrosurgical (ES) electrode and steel scalpel (SS) wound healing have reported poor initial tensile strength, a delay in reaching maximum tensile strength and an increased inflammatory response in the ES wounds. The hypothesis that a smaller needle (modified) electrode would give better wound healing than a standard electrode was tested. Using histology as a parameter of wound healing, incisions created by a modified electrode, a standard electrode and a steel scalpel were compared. Sixty Sha Sha mice were divided into 10 groups. Standardised dorsal skin incisions were made using steel scalpel, standard and modified electrosurgical cutting electrodes. Mice were sacrificed on days 0, 1, 2, 3, 5, 7, 9, 14, 28 and 42. The incised skin was processed for standard and immunohistochemical staining. The standard ES wound had significantly higher numbers of polymorphonuclear leukocytes in comparison to the SS and modified ES wounds (p less than or equal to 0.01). However, macrophage numbers were found to be significantly lower in the ES wounds when compared to the SS wounds on days two and five (p less than or equal to 0.05). The fibroblast response was delayed by up to two days in the ES wounds when compared to the SS wounds. Epithelialisation was completed by day two in the SS and modified ES groups but was only complete by day three in the standard ES group (p less than or equal to 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Tissue displacement methods in fixed prosthodontics

The various methods to accomplish gingival displacement have been described. The techniques have been noted and their relative advantages and disadvantages summarized. The practicing dentist can use this review to make better informed decisions regarding the method he or she chooses for the treatment of a particular patient.