Archives of Medicine and Health Sciences

: 2019  |  Volume : 7  |  Issue : 2  |  Page : 240--242

Radicular lingual groove: A contributory factor in periodontal pathology

Gaurav Didhra1, Jagjit Singh2, Rajan Gupta3, Parveen Dahiya3,  
1 Dental Hospital and Implant Centre, Mehatpur, Himachal Pradesh, India
2 Dental Hospital and Implant Centre, Mohali, Punjab, India
3 Department of Periodontics, Himachal Institute of Dental Sciences, Paonta Sahib, Himachal Pradesh, India

Correspondence Address:
Dr. Gaurav Didhra
Dental Hospital and Implant Centre, Opp. UCO Bank Main Bazar, Mehatpur - 174 315, Himachal Pradesh


Radicular gingival groove is a developmental anomaly most commonly occurring in the maxillary anterior teeth that acts as a hidden trap in the tooth which accumulates plaque and periodontal pathogens, leading to the formation of periodontal pocket with or without pulpal involvement. The diagnosis of these grooves in terms of radiographic images is very difficult to predict and can only be appreciated as per patient's chief complaint along with clinical examination of periodontal pocket depth with probing and endodontic treatment of tooth if pulpal involvement is present.

How to cite this article:
Didhra G, Singh J, Gupta R, Dahiya P. Radicular lingual groove: A contributory factor in periodontal pathology.Arch Med Health Sci 2019;7:240-242

How to cite this URL:
Didhra G, Singh J, Gupta R, Dahiya P. Radicular lingual groove: A contributory factor in periodontal pathology. Arch Med Health Sci [serial online] 2019 [cited 2022 Dec 5 ];7:240-242
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Palatogingival groove or radicular lingual grooves are developmental malformations that were described by Everett and Kramer (1972) and Robison and Cooley (1988). They are usually found on the lingual surface of maxillary lateral incisors.[1] They have an incidence rate ranging from 2.8% to 18%.[2] They originate when the central fossa crosses the cingulum and extend toward root portion in apical direction.[3] They act as a shelter for bacterial plaque and calculus accumulation, which makes it difficult for both the patient and the professional to clean it, resulting in the development of inflammation in the periodontal tissues adjacent to the groove, leading to the detachment of junctional epithelium, periodontal destruction, pocket formation, and alveolar bone loss.[4] The prognosis of tooth in such cases depends on both periodontal and endodontic treatment approaches as in most cases, the microbial flora of plaque may extend toward the pulp, leading to necrosis of the pulp with periapical pathologies. Accessory canals are the main source of communication between pulp and periodontium of incisors with radicular lingual grooves.[5]

The present case report demonstrates the management of a maxillary lateral incisor with radicular groove in the midpalatal region involving both endodontic and periodontal approaches along with the use of MTAD BioPure™ as a newly introduced material in periodontics for root conditioning.

 Case Report

A 36-year-old male patient reported to the clinic with the complaint of pain in the maxillary right lateral incisor for the last 2 weeks. Dental history revealed no previous trauma or any relevant finding. On clinical examination, the tooth was intact with no mobility and was tender on percussion with periodontal pocket depth of around 10 mm in the midpalatal region measured by a UNC-15 Periodontal probe [Figure 1]. Electronic pulp testing revealed no response showing the presence of nonvital pulp that may have necrosis with time due to the extension of periodontal pathology. Intraoral periapical radiograph showed the presence of lateral and periapical radiolucency [Figure 1]. Based on these findings, the tooth was found to have a radicular lingual groove with localized periodontitis along with necrotic pulp.{Figure 1}

A combined endodontic and periodontal approach was planned. In the first phase of the treatment, root canal treatment of the tooth was performed using 5.2% sodium hypochlorite with subsequent calcium hydroxide (Ca(OH)2) dressings after 1 week for 2 times followed by obturation. Then, localized flap surgery was performed over the area using intrasulcular incision showing a large palatogingival groove with calculus deposits along with bony defect [Figure 2]. Thorough scaling and root planing of the area was done along with debridement by using Gracey curette number 1/2 (Hu-Friedy). After this, odontoplasty of the groove was done using a round diamond bur to make it a smooth polished surface [Figure 2].{Figure 2}

The final step involved the root conditioning of the tooth surface with MTAD BioPure™ (mixture of tetracycline, citric acid, and detergent) [Figure 3]. After this, the flap was sutured back and covered with periodontal dressing (COE-PAK™ by GC) [Figure 3].{Figure 3}

The patient was recalled after 1 week, and his clinical condition was assessed with removal of periodontal dressing and sutures and was kept under observation. After 1 month, the periodontal condition of the tooth was assessed clinically by probing and much improvement was seen in terms of probing depth which was reduced to 4 mm with a clinical attachment gain of 6 mm (earlier, the probing depth was 10 mm) [Figure 4].{Figure 4}


Radicular lingual groove is one of the developmental anomalies of maxillary incisors that occurs as a result of infolding of the inner enamel epithelium and Hertwig's epithelial root sheath that creates a groove passing from the cingulum of the incisors toward apical direction onto the root; as a result, later on, this anomaly creates a niche for plaque and bacterial accumulation, leading to both pulpal and periodontal problems.[6] Recognizing palatogingival groove is not easy always as it may involve symptoms of true periodontal lesion or true endodontic lesion or a combination of both; the final diagnosis is made based on clinical examination and detecting a notch in the lingual surface of crown. More than 50% of the palatogingival grooves are seen to extend beyond the cemento-enamel junction onto the root surface. Among these grooves traversing the root, 43% have shown to extend apically <5 mm in distance, 47% between 6 and 10 mm, and 10% have shown extension beyond 10 mm.[1] Based on the invagination of the groove toward the pulp cavity, these have been termed as shallow/flat (<1 mm), deep (>1 mm), and a closed tube.[7]

Radicular lingual grooves are classified as simple and complicated. Simple grooves are less likely to communicate with pulp as they are shallow and represent only minute folding of Hertwig's epithelial root sheath, whereas complicated grooves are deep and more likely to communicate with the pulp, causing combined endodontic and periodontal lesion.[8] The final diagnosis of such combined lesions is aided by detecting notch in the tooth crown and periodontal probing.[9]

In the present case, the exploration of the lingual fossa of the tooth revealed fissure-shaped defect that was covered by plaque and calculus, and periodontal examination revealed a deep pocket depth of 10 mm in the midpalatal region. The pulp was also nonvital, with radiographs showing periapical and lateral radiolucency. First, endodontic therapy was completed; later on, periodontal therapy was initiated involving open flap debridement involving scaling and root planing with odontoplastly of the groove. After root planing, a smear layer is formed that serves as a physical barrier between the periodontal tissue and the root surface and may inhibit the formation of new connective tissue attachment to the root surface.[10] For this purpose, MTAD BioPure™ was used as a root-conditioning agent which showed excellent results in terms of clinical pocket depth reduction with gain in periodontal attachment levels. The patient was kept under observation and follow-up visits and showed excellent improvements in pocket depth reduction from 10 mm early to around 4 mm.

BioPure MTAD (Dentsply Tulsa Dental, USA) is a material originally developed as a final irrigant for endodontics. It is a mixture of doxycycline (a tetracycline isomer), citric acid, and polysorbate-80 (a detergent). MTAD has been reported to remove the smear layer effectively, eliminate microbes that are resistant to conventional endodontic irrigants and dressings, and provide sustained antimicrobial activity. Studies have shown better smear layer removal and enhanced fibroblastic attachment to the tooth surface of MTAD as compared to other root conditioners. This is in accordance with the study done by Zia et al., 2014,[11] and Tandon et al., 2015.[12]


It is, therefore, concluded that an interdisciplinary approach is required in such type of cases following both endodontic therapy and periodontal treatment. Here, we tried using MTAD which is a newly introduced product in the branch of periodontics as a root-conditioning agent that showed excellent results clinically.

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Conflicts of interest

There are no conflicts of interest.


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