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Ambiguity of lateral canals
*Corresponding author: Sangham Dinkar Madakwade, Department of Conservative Dentistry and Endodontics, VSPM’s Dental College and Research Center, Nagpur, Maharashtra, India. sangham358@gmail.com
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Received: ,
Accepted: ,
How to cite this article: Madakwade SD, Makade CS, Shenoi PR. Ambiguity of lateral canals. J Adv Dental Pract Res 2022;1:24-6.
Abstract
For successful endodontic therapy, clinicians must have a thorough understanding of the complexities present in the root canal system such as accessory canals, lateral canals, furcal canals, and apical ramifications. It has been reported in the literature that lateral canals and/or apical canals are likely to be associated with pulp disease and canal reinfection. As a result, this emphasizes the importance of infection control not only in the main canal but also throughout the root canal system and its variations. The current article presents with an insight into the clinical aspects of lateral canals.
Keywords
Accessory canals
Apical ramifications
Lateral canals
Root canal variations
INTRODUCTION
An adequate understanding of the intricacies of the root canal system is required for successful root canal treatment.[1] Accessory canals, lateral canals, furcal canals, and apical ramifications are all anatomical variations of the root canal system.[2,3]
“An accessory canal is a branch of the main pulp canal or chamber that communicates with the external root surface,” according to the American Association of Endodontists (AAE) Glossary of Endodontic Terms (AAE 2016).[4] A lateral canal, as per this definition, is a type of accessory canal that is located in the coronal or middle third of the root and usually extends horizontally from the main canal space.[1]
It has been reported in the literature that the lateral canals and the apical canals may be attributed to pulp disease, reinfection of root canals, and post-treatment disease.[3] As a result, this shows the importance of infection control not only in the main canal but also throughout the root canal system. According to the literature, pervasiveness of lateral and accessory canals is mentioned in the following [Table 1].[5-8]
| Investigators | Tooth studied | Total no of teeth | Method of study | Incidence |
|---|---|---|---|---|
| Dammaschke et al.[6] (2004) | Maxillary and mandibular molar | 100 | Scanning electron microscope | 79% |
| Ricucci et al.[5] (2010) | All teeth | 493 | Light microscope | 75% |
| Xu et al.[7] (2016) | Apical 3 mm of all teeth | 204 | Micro-computed tomography | 52% |
CLASSIFICATIONS OF LATERAL CANALS
Various authors proposed various classifications of lateral canal such as,
Yoshiuchi et al. (1972)[9] according to their location along the root length
De-Deus (1975)[10] categorized lateral canal, according to their location
Vertucci (1984)[11] lateral canals were classified based on their location
Weine (1989)[12] reported on three types of lateral lesions that can be seen on radiographs.
Type I: There is a lateral lesion but no apical lesion [Figure 1a]
Type II: Clearly differentiate between lateral and apical lesions [Figure 1b]
Type III: Lateral and apical lesions coincide (“Wrap around” lesion) [Figure 1c].
Recently, Ahmed et al. (2018)[4] introduced a different morphology classification system for accessory canals that can be used in research, clinical practice, and training [Table 2].
- (a) There is a lateral lesion but no apical lesion. (b) Clearly differentiate between lateral and apical lesions. (c) Lateral and apical lesions coincide.
| Configuration | Code |
|---|---|
| Accessory canal (s) located in one of the three-thirds of the root one of the three-thirds of the root | (CaO-C-aF) OR (Ma0-C-aF) OR (Aa0-C-aF) |
| An accessory canal starts with an a0 in one-third, and aF in another third of the root | (C, Ma0-C-aF) OR (M, Aa0-C-aF) |
| Accessory canals located in two of the three-thirds of the root | (CaO-C-aF, Ma0-C-aF) OR (CaO-C-aF, Aa0-C-aF) OR (Ma0-C-aF, Aa0-C-aF) |
| Accessory canals located in all thirds of the root | (CaO-C-aF, Ma0-C-aF, Aa0-C-aF) |
CLINICAL IMPLICATIONS, PRACTICABILITY, AND APPLICATION
Lateral canals can be suspected routinely on radiographic examination that is intraoral periapical radiograph depicting local periodontal ligament thickening on the root’s lateral surface. This can be suggestive of lateral periodontitis lesion.[5]
When detected, lateral canals are difficult to negotiate and instrumentation. Therefore, the irrigating solution like 2.5–5.25% sodium hypochlorite with 17% EDTA is used continuous with intermittent ultrasonic activation by an oscillating needle which is the most effective methods for irrigant penetration and cleaning of lateral canal.[8]
CONTROVERSY OF LATERAL CANALS TO FILL OR NOT TO FILL?
As one can assume from this discussion, although the significance of filling lateral canals on treatment outcome has been subject of debate.[5] There are no conclusive scientific data in this regard. However, the controversy related to its filling or not to filling is summarized in this [Table 3].[13-18]
| To fill | Not to fill |
|---|---|
| Bacteria do not concern if they are in the main canal or one of the lateral canals. They must be destroyed, and the “lateral orifice” must be sealed in the same way as the central apical foramen.[13] Versiani et al. (2019)[13] |
Although lateral canals have been shown to occur often, they may not always be visible radiographically following root canal filling. Even so, in the large majority of cases, failure to fill lateral canals does not result in endodontic treatment failure, which is defined by a post-treatment lateral lesion.[14] Weine (1984)[14] |
| A lateral canal that is not sealed can lead to negative consequences and responsible for failure and subsequently may require nonsurgical or surgical retreatment[13] Versiani et al. (2019)[13] |
The histologic condition of tissue in lateral canals and apical ramifications reflects the pulp’s condition in the main canal.[16] Campus (1991)[16] |
| Detection of a lateral canal and disinfection of these avenues becomes, much more important, when there is an obvious lateral lesion.[15] Teja and Ramesh (2020)[15] |
For a successful root canal therapy, lateral canal filling is not usually required.[17] Camps and Lambruschini (1887)[17] |
| In vital cases, when the filling material was not visible within the lateral canals, the tissue there remained viable, and the outcome was unaffected.[5] Dmenico Ricuui (2010)[5] |
CONCLUSION
With the advances in technology related to visualization help in diagnosis and it also assisted in treatment. When the pulp is vital, then not treating these canals would be more practical for practitioner. If there is an evident lateral lesion, finding a lateral canal and disinfecting and filling it is crucial to the final outcome of endodontic therapy.
Declaration of patient consent
Patient’s consent not required as there are no patients in this study.
Financial support and sponsorship
Nil.
Conflicts of interest
Author Dr Pratima Shenoi is on the Editorial Board of the journal.
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