Regenerative endodontic treatment of immature permanent teeth after mechanical instrumentation with XP-Endo Finisher.

INTRODUCTION: The traditional treatment of immature permanent teeth with necrotic pulp involves creating an apical barrier by using calcium hydroxide or an MTA plug for an extended period of time. A novel therapeutic approach called regenerative endodontic procedures (REP) is used to allow root development to continue.

Application of Contemporary Magnifying Methods in the Diagnostics of Occlusal Carious Lesions on First Permanent Molars in Children.

INTRODUCTION: Dental operating microscopes (DOM) enable dentists to examine, with the aid of magnification and photodocumentation in clinical conditions, the occlusal anatomy of newly erupted permanent molars and to detect any early carious lesions more precisely. AIM: To determine the advantages of magnifying technology in detecting early occlusal carious lesions in newly erupted permanent first molars. MATERIALS AND METHODS: We examined 176 first molars of 44 children divided into two age groups: 7-8 and 9-10 years. The surfaces of each of the teeth were examined after they were cleaned with a brush without paste. The diagnoses were first made using only illumination and a clinical examination. These were followed by a visual examination of the occlusal surface using a DOM at ×8 magnification. A photo of the occlusal surface was then taken with a camera at the respective magnification for the purposes of photodocumentation. RESULTS: This study demonstrated that dental operating microscopes increased by 7% the rate of successful detection of early caries lesions on the occlusal surfaces. There was also a significant increase of the number of diagnosed cavitated caries in the dentine in comparison with those detected with naked eye. Using DOMs in pediatric dentistry facilitates the more detailed and precise diagnosing of early stage carious lesions and/or cavitations in the fissures. CONCLUSION: The use of a DOM facilitates differential diagnosing between deep fissures and early carious lesions, which is a key point in the assessment of occlusal surfaces of newly erupted permanent molars, necessary for their preventative sealing and micro-invasive treatment.

Comparative Analysis of Root Dentin Loss when Using Modern Mechanical Cleaning Instruments in Immature Permanent Teeth.

INTRODUCTION: The full decontamination and disinfection of the root canal system is essential for the success of regenerative endodontic procedures. The current literature does not have information regarding mechanical cleaning of immature teeth with contemporary endodontic instuments. AIM: To compare the thickness and volume of the dentin removed from the roots of immature teeth after endodontic preparation using XP-endo Finisher, GentleFile Brush and a standard H-file scraping technique through micro-computed tomography. METHODS: The study included 51 immature permanent molars. Endodontic access was prepared and without performing preliminary extirpation of the pulp, the teeth were divided into three groups. The first group of teeth were instrumented for two minutes with XP-endo Finisher, the second - two minutes with Gentlefile Brush, in the third group the root canals walls were scraped with a No. 40 H-file. The thickness and the volume of the removed dentin was assessed using micro-CT imaging before and after the use of the instruments. RESULTS: There is no statistically significant difference in the mean values of thickness of dentin removed between the teeth, prepared with XP-endo finisher and Gentlefile Brush. When comparing the mean values of volume of dentin removed between the separate groups, a statistically significant difference was discovered for every compared pair with the highest volume of removed dentin in the group prepared with a hand instrument. CONCLUSION: The endodontic systems tested when used in immature permanent teeth remove significantly less quantity of hard dental structures compared to a hand file for scraping the root canal.

Role of PDGF-BB in proliferation, differentiation and maintaining stem cell properties of PDL cells in vitro.

OBJECTIVE: Platelet-derived growth factor-BB (PDGF-BB) is one of the most abundant growth factors in platelet derived products and has been shown to stimulate regeneration after tissue injury. There is a population of mesenchymal stem cells (MSC) in human periodontal ligament (PDL) which can contribute to tissue regeneration under appropriate conditions. DESIGN: PDL cells were isolated and characterized using stem cell and differentiation markers via immunofluorescence and flow cytometry and then cultured in vitro and treated with different concentrations of PDGF-BB. The effect of PDGF-BB on cell proliferation, stem cell and differentiation markers expression, soluble collagen production, lysyl oxidase (LOX) activity, alkaline phosphatase (ALP) activity and calcium nodules formation was assessed. RESULTS: PDGF-BB stimulated the proliferation of cells with the maximum effect at 50ng/mL. The growth factor increased the expression of stem cell markers and SPARC; Col1a2 expression was decreased, whereas the expression of Col3a1 remain unchanged. Soluble collagen production, ALP activity and calcium nodules formation were also significantly decreased by PDGF-BB; LOX activity was significantly increased. CONCLUSIONS: PDGF-BB is a powerful promoter of cell proliferation and increases the expression of stem cell markers; inhibites collagen production and mineraliration but accelerates the maturation of collagen chains through increased LOX activity and SPARC expression.

Use of platelet concentrates in oral and maxillofacial surgery: an overview.

OBJECTIVE: To describe and provide a comprehensive overview on the development, use and efficacy of autologous platelet concentrates in different in vitro and in vivo studies focusing on oral and maxillofacial pathologies. MATERIALS AND METHODS: Present work employs an extensive critical overview of the literature on the development and application of platelet concentrates. RESULTS: Platelet concentrates are innovative endogenous therapeutic agents which gained a lot of interest in different medical and dental disciplines due to their potential ability to stimulate and increase regeneration of soft and hard tissues. The effect of platelet-derived products is considered to be a result of the high number of platelets which contain a wide range of growth factors. They are not just therapeutic products but autologous blood concentrates containing active molecules. The quality of platelet concentrates may vary according to the individual physical state of donors making it difficult to to compare the outcomes of their application. Although, there are many studies analyzing the properties of these biomaterials both in vivo and in vitro, a consensus regarding their efficacy still has to be reached. CONCLUSION: Evidences described in the literature on the efficacy of platelet concentrates in procedures in oral and maxillofacial region are controversial and limited. In order to clarify the real advantages and priorities for the patients, when the blood-derived products are applied, further in vitro and in vivo research about the activity of PRP and PRF on the dental cells biology should be conducted.