Calcium hydroxide: study based on scientific evidences

Abstract

he characteristics of calcium hydroxide come from its dissociation into calcium and hydroxyl ions. The action of these ions on tissues and bacteria explains the biological and antimicrobial properties of this substance. Under the conditions of this retrospective of literature, based on scientific evidences, it is possible to state that: 1. Dentin is considered the best pulpal protective, and calcium hydroxide has proved, through numerous studies, its capability of inducing the formation of a mineralized bridge over pulpal tissue. 2. It is necessary, whenever possible, to provide time for calcium hydroxide paste to manifest its potential of action on the microorganisms present in endodontic infections. The maintenance of a high concentration of hydroxyl ions can change bacteria enzymatic activity and promote its inactivation. 3. The site of action of hydroxyl ions of calcium hydroxide includes the enzymes in the cytoplasmic membrane. This medication has a large scope of action, and therefore is effective on a wide range of microorganisms, regardless their metabolic capability. In microbial world, cytoplasmic membranes are similar, irrespective from microorganisms morphological, tinctorial and respiratory characteristics, which means that this medication has a similar effect on aerobic, anaerobic, Gram-positive and Gram-negative bacteria. 4. Calcium hydroxide as temporary dressing used between appointments promotes better results on the periapical healing process than the treatment in one appointment.

In vitro antimicrobial activity of endodontic pastes with propolis extracts and calcium hydroxide: a preliminary study

“…By testing a mixture of propolis and calcium hydroxide against a polymicrobial culture extracted from primary tooth root canals, better results were observed than those obtained with calcium hydroxide plus propylene glycol. Calcium hydroxide was chosen because it is well established as an endodontic dressing (10), but its use is still controversial in primary teeth (11). A recent systematic review with meta-analysis, however, reported that calcium hydroxide has limited effectiveness in eliminating bacteria from human root canals when assessed by culture techniques (20).…”

“…This material has been extensively used in dentistry because of its ability to stimulate mineralization and its excellent antimicrobial action (10).…”

Antimicrobial potential of medicaments used in healing process in dogs' teeth with apical periodontitis

“…It is necessary, whenever possible, to give enough time for the CHP to manifest its potential action against the microorganisms present in endodontic infections. The maintenance of a high concentration of hydroxyl ions can change the enzymatic activity and promote the microbial inactivation (8).…”

“…The effectiveness of intracanal dressings on the success rate in teeth with apical periodontitis has been discussed (1)(2)(3)(4)(5)(6)(7)(8). Byström et al (2) recovered bacteria from one of 35 root canals treated by calcium hydroxide paste (CHP) after 30 days and suggested that the endodontic treatment of infected root canals can be completed in two sessions when CHP is used as an intracanal dressing.…”

Estudo longitudinal do sucesso clínico-radiográfico de dentes tratados com medicação intracanal de hidróxido de cálcio

“…As principais características do hidróxido de cálcio se desenvolvem a partir da sua dissociação em íons cálcio e hidroxila. A ação desses íons explica as características biológicas e antimicrobianas desta substância, que se manifestam a partir de ações enzimáticas tanto sobre as bactérias quanto sobre os tecidos 3,8,9 . Portanto, o emprego do hidróxido de cálcio na Endodontia se deve ao seu caráter antimicrobiano, potencializando a desinfecção do SCR, e também pela sua participação no processo de reparo periapical.…”