[Soft laser and its application areas in oral surgery and stomatology]. / Der Low-Level-Laser in der Oralchirurgie und Stomatologie.

Low-level lasers (LLL) are used in the stomatology and oral surgery field of dentistry. Due to the biostimulation or biomodulation and photodynamic effect, the healing process of soft-tissue and bone wounds can be accelerated. The indication in oral surgery is to achieve a faster bone healing after tooth extraction, but also to improve the osseointegration in implants. The advantage in stomatology is pain alleviation and improved healing in aphthae and cold sores as well as symptom relief in mucositis. Due to the use free of side effects and low time effort, the LLL offers high patients' comfort.

Guided biopsy of osseous pathologies in the jaw bone using a 3D-printed, tooth-supported drilling template.

Suspicious radiological findings in the jaw bone require histopathological examination for the confirmation of a diagnosis. As pathologies in this region are difficult to reach or are in close proximity to relevant anatomical structures, e.g. tooth roots or nerves, they often represent a challenge. Such factors may adversely affect the predictability of the surgical outcome of a biopsy of the osseous tissues. This technical note introduces a novel method for performing a digitally planned, guided biopsy. For this purpose, a cone beam computed tomography scan and an intraoral scan are superimposed using specific planning software. The resulting three-dimensionally printed, tooth-supported drilling template is designed for a trephine biopsy. It allows a precise, minimally invasive approach, with an exact three-dimensional determination of the biopsy location prior to surgery. The risk of devitalization of the neighbouring teeth or possible damage to the nerve structures can be minimized. Furthermore, a small access flap can be sufficient. In summary, the method of bone biopsy presented here allows high precision and greater predictability for biopsy sampling and is minimally invasive for the patient.

Influence of root canal disinfectants on growth factor release from dentin.

INTRODUCTION: During dentinogenesis, growth factors become entrapped in the dentin matrix that can later be released by demineralization. Their effect on pulpal stem cell migration, proliferation, and differentiation could be beneficial for regenerative endodontic therapies. However, precondition for success, as for conventional root canal treatment, will be sufficient disinfection of the root canal system. Various irrigation solutions and intracanal dressings are available for clinical use. The aim of this study was 2-fold: to identify a demineralizing solution suitable for growth factor release directly from dentin and to evaluate whether commonly used disinfectants for endodontic treatment will compromise this effect. METHODS: Dentin disks were prepared from extracted human teeth and treated with EDTA or citric acid at different concentrations or pH for different exposure periods. The amount of transforming growth factor-ß1 (TGF-ß1), fibroblast growth factor 2, and vascular endothelial growth factor were quantified via enzyme-linked immunosorbent assay and visualized by gold labeling. Subsequently, different irrigation solutions (5.25% sodium hypochloride, 0.12% chlorhexidine digluconate) and intracanal dressings (corticoid-antibiotic paste, calcium hydroxide: water-based and oil-based, triple antibiotic paste, chlorhexidine gel) were tested, and the release of TGF-ß1 was measured after a subsequent conditioning step with EDTA. RESULTS: Conditioning with 10% EDTA at pH 7 rendered the highest amounts of TGF-ß1 among all test solutions. Fibroblast growth factor 2 and vascular endothelial growth factor were detected after EDTA conditioning at minute concentrations. Irrigation with chlorhexidine before EDTA conditioning increased TGF-ß1 release; sodium hypochloride had the opposite effect. All tested intracanal dressings interfered with TGF-ß1 release except water-based calcium hydroxide. CONCLUSIONS: Growth factors can be released directly from dentin via EDTA conditioning. The use of disinfecting solutions or medicaments can amplify or attenuate this effect.