AvueCal - Premixed Calcium Hydroxide
Avue Cal is a ready-to-use paste with a calcium hydroxide formulation. It is a radiopaque, extremely alkaline water-soluble paste that can be readily cleansed and removed from the canal. Highly indicative in weeping canals, temporary root canal filling material.
Calcium hydroxide (Ca(OH)2) has been widely used in endodontics as an intracanal medicamentĀ to eliminate the remaining microorganisms after chemomechanical preparation.Ā
Dentists have used calcium hydroxide in clinical practice for over a century.Ā InĀ 1920, HermanĀ introduced calcium hydroxide to dentistry as a pulp-capping material but today it is used widely in endodontics.
Avuecal is widely used due to itsĀ advantagesĀ such as:
ā¢ Initially bactericidal effect then bacteriostatic.
ā¢ Promotes healing and repair.
ā¢ High pH stimulates fibroblasts.
ā¢ Stops internal resorption.
ā¢ Neutralizes low pH of acids.
ā¢ Inexpensive and easy to used
Antimicrobial Effect of AvueCal
TheĀ release ofĀ hydroxyl ionsĀ in an aqueous environment is essential for the activation ofĀ calcium hydroxideĀ against microbes.Ā These ions reacted intensively withĀ several biomolecules due to their highly oxidant free radicals.
As this reactivity is unspecified, the free radicals most likely gathered at the sites of generation. Hydroxyl ions have fatal effects on bacterial cells. They may damage the cytoplasmic membrane of bacteria, denature their proteins, or damage the DNA.
Used as disinfecting dressing
The appl
ication of calcium hydroxide paste
Ā atĀ intervals of at least 7 daysĀ is able to eliminateĀ and/or reduce the total number of bacteria surviving even
Ā after biomechanical preparation.
The Effect of calcium hydroxide onĀ pro-Inflammatory cytokines was studiedĀ and concludedĀ that itĀ leads toĀ denaturation ofĀ these pro-inflammatory mediatorsĀ such as interleukin-1Ā Ī±Ā (IL-1Ī±), tumor necrosis factor Ī±(TNFĀ Ī±) and calcitonin gene-related peptide (CGRP) that is a potential mechanism by which calcium hydroxide contributes to the resolution of periradicular periodontitis.
Intracanal medicament inĀ WeepingĀ Canal
Weeping canalĀ is a canal from whichĀ constant clear or reddish exudation is appeared.
This exudate isĀ associatedĀ with a largeĀ apical radiolucency. TheĀ tooth is difficult to treatĀ as when opened, exudate stops but it again reappears in next appointment.
Signs andĀ symptoms varies from symptomlessĀ to tenderness to percussion and palpation.Ā ObturationĀ of canals with exudates is contraindicated.
For such teeth, application of calcium hydroxide in the canalĀ after drying with sterile
absorbent paper points is helpful. This is because of itsĀ high alkalinity, which changes
the acidic pH of periapical tissues to a more basic environment.
Two other mechanisms have also been proposed:
1)Ā Build up bone in the lesionĀ due to the calcifyingĀ potential ofĀ calcium hydroxideĀ and
2) The residual chronicallyĀ inflamed tissue is cauterizedĀ by the caustic action ofĀ calcium hydroxide.
PerforationĀ Management
It hasĀ many advantages in this treatment modalityĀ such as stimulation ofĀ hard tissue formation, easy preparation, rapid resorptionĀ whenĀ extruded into the periodontium andĀ healing enhancement of damaged periodontal tissues,Ā we can use Avuecal or Avuepex or MTA/Bioceramics for the perforation management
Role inĀ RootĀ Resorption
Root resorption can be classified into internal, external or root-endedĀ resorption based.
on the site of origin, andĀ can affect the cementum and/or dentine of the root.Ā Since calcium hydroxide hasĀ alkaline pH,Ā it actively influences the local environment around aĀ resorptive area by reducing osteoclast activity and stimulating repair.
The alkaline calcium hydroxide neutralizes the acidic environment which exists in the regionĀ of resorption, reversing the reaction and thus stimulatingĀ hard tissue formation.Ā The diffusion of hydroxyl ions released by calcium hydroxide through the dentinal tubules that directly communicate withĀ periodontal space would increase the pH of periodontal spaceĀ from 6.0 to 7.4Ā -Ā 9.6.Ā To treatĀ an internal resorption, the canalĀ and resorption lacuna areĀ filled withĀ calcium hydroxideĀ paste.
TheĀ resorptive defect should be filled withĀ calcium hydroxideĀ at 3-month intervalsĀ until it revealsĀ hard tissue formation, confirmed by both directĀ examination through the access cavity and radiograph.Ā AfterĀ establishment of physical barrier, the defect can be compacted with Gutta-percha.
