Dental Hypotheses

: 2014  |  Volume : 5  |  Issue : 1  |  Page : 11--13

Possible use of calcifying nanoparticles in immature root apex treatment

Mohammed S Alenazy1, Hezekiah A Mosadomi2,  
1 Ministry of Health, Endodontic Postgraduate Student, Riyadh Colleges of Dentistry and Pharmacy, Riyadh, Saudi Arabia
2 Oral and Maxillofacial Pathology, Research Center, Riyadh Colleges of Dentistry and Pharmacy, Riyadh, Saudi Arabia

Correspondence Address:
Mohammed S Alenazy
Riyadh Colleges of Dentistry and Pharmacy, P.O. Box 21437, Riyadh - 11475
Saudi Arabia


Introduction: There are reports in the literature, which describe different techniques and materials in the challenging management of thin dentin walls and immature root apex. It has been suggested that calcifying nanoparticles (CNPs) could be used in the management of these conditions. The Hypothesis: Compositionally modified CNPs made into a paste could become efficacious in managing thin dentin walls and immature root apex. Calcium and phosphate ions when mixed with CNPs could form a synthetic nanopaste that clinicians could use to manage thin dentin walls and to get a biological seal for immature root apex. Evaluation of the Hypothesis: CNPs can replicate and could facilitate the aggregations of calcium hydroxyapatite to produce a self-surrounding shell. These characteristics of CNPs could be used through their biomineralization process as initial nidus of calcification for further calcification progression to achieve total biological apical seal. If the hypothesis could be supported by biomineralization behavior of the paste (CNPs, Ca2 + , and PO4 ), a new therapeutic agent would have been added to the armamentarium of endodontists. There is need for more in vivo and in vitro investigations of modified nanopaste to manage these conditions.

How to cite this article:
Alenazy MS, Mosadomi HA. Possible use of calcifying nanoparticles in immature root apex treatment.Dent Hypotheses 2014;5:11-13

How to cite this URL:
Alenazy MS, Mosadomi HA. Possible use of calcifying nanoparticles in immature root apex treatment. Dent Hypotheses [serial online] 2014 [cited 2021 Mar 5 ];5:11-13
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Immature apex and thin dentin walls are challenging cases to manage in nonvital endodontic practice especially in young permanent tooth. Previously the lines of treatment of nonvital teeth with immature apex and/or thin dentin are restricted to filling paste, customized fitted gutta-percha, and apical surgery. [1] Limited success of these procedures has led to enhanced interests in "apexogenesis", completing apical development phenomenon, or "apexification" forming a hard apical barrier. [2]

The use of various materials had been recommended for producing hard apical root barrier. In both situations, calcium hydroxide was the most common material used in apexification treatment for immature nonvital teeth and/or thin wall dentin. Although calcium hydroxide has many disadvantages, several studies reported the success of this traditional method of using this material. [3],[4],[5]

The alternative method of the calcium hydroxide apexification is the one-visit method of forming an artificial apical barrier. Parirokh and Torabinejad revealed that mineral trioxide aggregate (MTA) has been recommended for various endodontic procedures. [6] This approach has been described as the nonsurgical filling of a biocompatible material condensed into the apical third of the root canal. Therefore, creating an immediate apical barrier facilitates the root canal filling in one visit. [7] The superiority of this method is less treatment time, and the formation of a satisfactory apical seal barrier. [8]

Several materials used in apexification technique include tricalcium phosphate, [9] calcium hydroxide, [10] freeze-dried bone, [11] freeze-dried dentin, [12] and calcium phosphate. [13] Ham et al., explained that blood clot formation through a controlled overinstrumentation in the periapical area is the initiator of an apical development that close the root apex "revascularization". Consequently the use of a nanotechnology material could improve the management of nonvital immature apex and thin wall dentin, than the methods presently available and then leads to closure of root apex. [14]

 The Hypothesis

Jing et al., hypothesized the therapeutic use of calcifying nanoparticles (CNPs) in enamel tooth repair in vitro. Other researchers proposed a gelatinous synthetic agent to be applied on cracked tooth surface. The action of this material is to limit further propagation of the crack deeper into the dentin. [15] The hypothesis could be made that the synthesis of a nanopaste containing modified CNPs compacted at the root end of immature apex and/or thin wall dentin will produce a biological seal and repair the root apex end. The procedure appears more preferable than an artificial barrier because the result is more biological.

 Evaluation of the Hypothesis

CNPs or nanobacteria have been found in different parts and fluids of human saliva, tooth surface, plaque, calculus, and pulp stones. They have several morphological shapes and their diameter sizes range from 80 to 500 nm. [16],[17] CNPs have the ability to replicate as well as to facilitate aggregation of calcium hydroxyapatite as shell surrounding the CNPs. [18] These characteristics of CNPs could be used through their biomineralization process potential as initial core of calcification for further calcification progression. [19] It is documented that essential components of biomineralization are calcium and phosphate ions. [20] There is evidence that CNPs initiates their mineralization mechanism when calcium concentration and phosphorus concentration reach 2.5 and 1.0 mM, respectively. [21]

The theoretical treatment modality is controlled overinstrumentation to the apical part to create a bleeding area which will allow the formation of blood clot that will serve as a temporary blockage of the canal which prevents escape of the applied nanopaste. This means that a nanopaste of CNPs, Ca2 + and PO4− will be applied after the formation of blood clot inside the canal. At the same time the clot will also serve as a matrix and provide growth factors and nutrition sources for CNPs. The possible drawbacks of nanopaste and the theoretical treatment modality are the ability to control the mineralization degree and CNPs activity.

In conclusion, if this hypothesis supports the behavior of the paste (CNPs, Ca2 + and PO4− ), then a new biomaterial would have been added to the therapeutic choices of endodontic management of nonvital immature apex and or thin wall dentin. However, more in vivo and in vitro investigation of modified nanopaste are needed.


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