Effects of mechanical instrumentation and chemical irrigation on the root canal dentin and surrounding tissues

Abstract

Preparation and disinfection of the root canal aims to remove organic and inorganic tissue from within the root canal, reduce the number of microorganisms, neutralize endotoxins inside the dentin, and prepare the root canal for proper obturation. These aims can be achieved in many cases to a degree that promises a high chance of success through a combination of mechanical preparation and chemical disinfection—in other words, irrigation and medication. Preparation and disinfection both physically and chemically act on the lumen of the root canal itself, trying to remove as much infected material as possible, but also act on the surrounding dentin and all of its components including the dentinal tubules. The chemomechanical process attempts to remove the adhering biofilm as well as microorganisms and their by‐products. It is important to investigate the effect of various treatment options on root canal dentin, the periodontal ligament, and the surrounding alveolar bone. When mechanical processes and chemical agents are applied to a substrate such as dentin, this implies that the dentin will be altered or modified in structure, composition, and/or physical properties. This review aims to summarize the present knowledge on the effects of mechanical instrumentation and chemical irrigation on the root canal dentin and surrounding tissues.

Effects of two combinations of triple antibiotic paste used in endodontic regeneration on root microhardness and chemical structure of radicular dentine

“…However, these chemical agents may negatively affect the chemical, physical, and mechanical properties of radicular dentine (19). Clinical studies have found that the increase in root wall thickness of immature teeth after endodontic regeneration is limited to the mid-and/or apical root rather than the cervical region (3,20), which is the area prone to fracture in treated immature teeth (21).…”

Intracanal Irrigating Solutions Prior to Calcium Hydroxide Medication and Its Effects on Root Dentin Strength

“…However, adverse effects of NaOCl irrigation on dentin's mechanical properties (3,10,11,13,19) have been reported, including decrease of microhardness (10), flexural strength (11) and elastic modulus (3). Sodium hypochlorite promoted loss of dentinal organic components (19) because this solution is a non-specific proteolytic agent. Organic phase depletion may change mechanical properties (9), due to the fact that dentin has 22% organic material, especially type I collagen.…”

“…Collagen plays an important role during dentin structural formation and it is responsible for sustaining dentinal mineral content (19). By losing this organic content, dentinal elastic module and flexural strength decline (3,10).…”

“…The use of EDTA for longer periods (20 to 40 min) attempted to simulate its use in atresic canals. In these situations, EDTA is used along all root canal preparation, improving the file actions by lubrication and decalcification of dentin structure (2,19).…”

Regenerative Endodontics: An Evidence Based Review

“…Regenerative endodontic procedures in adults There are numerous reports which state that the failure of root canal treatment is the result of improper cleaning and shaping and not improper obturation [62] . Conventional root canal therapy leads to the loss of reparative capacity, increased loss of tooth structure, brittleness [63] and the loss of a protective mechanism against noxious stimuli. A search for better methods to treat pulp diseases is being researched.…”