Endodontic Management of Radix Entomolaris in First and Third Mandibular Molars with Hybrid Rotary Systems A Case Series.

Transcription

1 Annals of Dental Research (2011) Vol 1 (1): Mind Reader Publications: All Rights Reserved Annals of Dental Research Case Series Endodontic Management of Radix Entomolaris in First and Third Mandibular Molars with Hybrid Rotary Systems A Case Series. Hora Baljeet S a, Garg Saurabh a, Bhardwaj Davinder a, Garg Rishu a a Department of Conservative Dentistry and Endodontics, Guru Nanak Dev Dental College, Sunam, Punjab, India Correspondence to Dr. Baljeet S Hora, Department of Conservative Dentistry and Endodontics, Guru Nanak Dev Dental College, Sunam, Punjab, India Phone: +91- Article Info Received: 20 July 2011 Revised: 14 September 2011 Accepted: 16 October 2011 Abstract Aberrations in root canal systems are a commonly occurring phenomenon. A thorough knowledge about the normal and abnormal variation of anatomy of the teeth and their detection is essential for clinical success. Mandibular molars show a considerable variation in root canal morphology. Mandibular molars can have an additional root located lingually (the radix entomolaris) or buccally (the radix paramolaris). Inspite of all procedural protocol if clinician misses an additional root or canals it could lead to failure of endodontic treatment. This case report discusses endodontic management of mandibular molars with a radix entomolaris. Annals of Dental Research (2011) 1(1), Keywords: Anatomical variations, radix entomolaris, endodontic treatment, mandibular molar Copyright: 2011 Hora et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited A DR- 05

2 Radix Entomolaris Hora et al Introduction The main objective of root canal treatment is thorough mechanical and chemical cleansing of the entire pulp cavity and its complete obturation with an inert filling material and a coronal filling preventing ingress of microorganisms 5. One of the main reasons for treatment failure is incomplete removal of pulp tissue and microorganisms from the root canal system. Therefore, the first step for successful treatment is an exact diagnosis of the root canal system and recognition of its variations. It is known that the mandibular molar can display several anatomic variations. This anatomic abnormality is an additional challenge, which influences all the stages of treatment including case assessment, access cavity design, canal orifice localization and cleaning and shaping of the root canal system 14. It is of utmost importance that the clinician be familiar with the root and root canal anatomy. The majority of mandibular molars are two rooted with two mesial and one distal canal 5. In most cases, the mesial root has two canals, ending in two distinct apical foramina or sometimes these merge together at the root tip to end in one foramen. The distal root typically has one kidney shaped root canal, although if the orifice is particularly narrow and round, a second distal canal may be present 13. Like the number of root canals, the number of roots may also vary. The major variant in this tooth type is the presence of an additional third root, a supernumerary root which can be found lingually. This macrostructure, which is first mentioned in the literature by Carabelli (1844), is called as Radix Entomolaris (RE). An additional root at the mesiobuccal side is called the Radix Paramolaris (RP). 2 The RE is located distolingually, with its coronal third completely or partially fixed to the distal root. The dimensions of the RE can vary from a short conical extension to a mature root with normal length and root canal. In most cases the pulpal extension is radiographically visible. In general, the RE is smaller than the distobuccal and mesial roots and can be separate from, or partially fused with, the other roots. Carlsen and Alexandersen describes four different types of RE according to the location of the cervical part of the RE: types A, B, C and AC. Types A and B refer to a distally located cervical part of the RE with two normal and one normal distal root components, respectively. Type C refers to a mesially located cervical part, while type AC refers to a central location, between the distal and mesial root components. This classification allows for the identification of separate and nonseparate RE. 2 De Moor et al classified RE into three types based on the curvature of the separate RE variants in bucco-lingual orientation. Type I refers to a straight root or root canal, while type II refers to an initially curved entrance which continues as a straight root or root canal. Type III refers to an initial curve in the coronal third of the root canal and a second curve beginning in the middle and continuing to the apical third. 2 The presence of a separate RE in the first mandibular molar is associated with certain ethnic groups. In African population a maximum frequency of 3% is found, while in Eurasian and Indian population the frequency 74 ADR, Vol 1, Issue 1, 2011

3 Hora et al Radix Entomolaris is less than 5%. In population with Mongloid traits the RE occurs with a frequency that ranges from 5% to more than 30%. 2 This case report describes the diagnosis and endodontic management of two mandibular molars with three roots (one mesial, two distal that is distobuccal and an additional distolingual) and four canals. CASE REPORT 1 A 35 year old female patient reported to the Department of Conservative Dentistry and Endodontics, with a chief complaint of severe pain in right lower back tooth region for three days. Medical history was noncontributory. On clinical examination the mandibular right third molar #48 was carious and tender on palpation and percussion. Periodontal probing and mobility was within normal limits. The tooth was very sensitive to cold and hot. Tooth showed positive response on vitality testing. Intraoral periapical radiograph revealed a deep carious lesion in close proximity to the pulp with periodontal ligament widening. This radiograph also showed that the tooth had an additional distolingual root (Fig 1). Based on the subjective and objective findings, a diagnosis of acute irreversible pulpitis with apical periodontitis was made. Endodontic treatment of the involved tooth was planned. The procedure was explained to the patient with possible outcomes and complications. The consent was taken from the patient before the procedure. Local anesthesia was administrated. The tooth was isolated under rubber dam and access cavity was prepared with distolingual extension to provide proper access to distolingual canal. The canal orifices were located using an endodontic explorer (DG-16 endodontic explorer, Dentsply, United Kingdom). The root canals were explored with a K- file ISO 15 (Mani, prime dental, Mumbai) and working length determination was performed with Root ZX II apex locator (J Morita) and confirmed radiographically (Fig 2). The distal, mesiobuccal and mesiolingual root canals were shaped with ProTaper universal rotary instruments (Dentsply Malliefer) in crown down manner. Apical preparation was done till size F2 Protaper file. RE was prepared with K3 system (Sybron Endo). Apical preparation was done with 4% of 25 no. K3 NiTi file. During canal preparation Glyde (Dentsply Malliefer) was used as a lubricant. The canals were irrigated with 5.25% sodium hypochlorite, 0.2% chlorhexidine gluconate alternatively during instrumentation and finally with normal saline. The canals were then dried with absorbent paper points (Dentsply Malliefer). Master cone selection radiograph was taken (Fig 3). Obturation was performed with corresponding gutta percha points (Dentsply Malliefer and K3 Sybron Endo) and AH plus sealer (Dentsply Malliefer). The access cavity was sealed with Glass ionomer cement and then with temporary restorative material Coltosol F (Coltene Whaledent) (Fig 4). The patient was recalled for the permanent restoration. ADR, Vol 1, Issue 1,

4 Radix Entomolaris Hora et al Figure 1: Preoperative diagnostic radiograph Figure 2: Determination of working length Figure 3: Master cone selection Figure 4: Postoperative radiograph CASE REPORT 2 A 16 year old male patient reported to the department of Conservative Dentistry and Endodontics, Guru Nanak Dev Dental College and Hospital, Sunam with a chief complaint of pain and swelling in right lower back tooth region for ten days. Medical history was noncontributory. Clinical evaluation revealed gross decay in mandibular right first permanent molar #46. Intraoral sinus tract was present in buccal vestibule at the marginal gingiva in relation with tooth 46. Tooth showed negative response on vitality testing. Tooth was tender on palpation and percussion. Intraoral periapical radiograph revealed a deep carious lesion progressing towards pulp chamber. This radiograph also showed that the tooth had an additional distolingual root and widening of lamina dura (Fig 5). Based on the clinical and radiographic findings, diagnosis of pulpal necrosis with chronic periapical periodontitis was made. A comprehensive treatment plan was devised to restore the tooth which consisted of endodontic treatment followed by full crown restoration. The procedure was explained to patient with possible outcomes and complications. Patient consent was taken before the procedure. The tooth was isolated under rubber dam and access was made to the pulp chamber without local anaesthesia. The conventional triangular access cavity was modified into a more trapezoidal cavity in order to locate and open the orifice of the distolingually located radix entmolaris. The canal orifices were located with DG-16 endodontic explorer and root canals were explored using K-file ISO 15 (Mani, prime dental, Mumbai). Working length was calculated using an apex locator (Root ZX II, J Morita) and confirmed radiographically (Fig 6). The distal root canal was prepared in a crown down method using rotary Protaper universal instruments 76 ADR, Vol 1, Issue 1, 2011

5 Hora et al Radix Entomolaris (Dentsply Malliefer). The mesiobuccal, mesiolingual root canals and RE were prepared with K3 system. During canal preparation Glyde was used as a lubricant and the root canals were irrigated alternatively with sodium hypochlorite and saline. An interappointment calcium hydroxide and iodoform dressing (Calciplus) was placed in the canals and temporized. After two weeks, access was regained and calcium hydroxide was removed by irrigation with normal saline. Master cone selection radiograph was taken (Fig 7). The canals were then dried with absorbent paper points. Obturation was performed with corresponding gutta percha points (Dentsply Malliefer and K3 Sybron Endo) and AH plus sealer (Dentsply Malliefer). The access cavity was sealed with Glass ionomer cement and then with temporary filling material Coltosol F (Coltene Whaledent) (Fig 8). The patient was recalled for the permanent restoration followed by full crown restoration. Figure 5: Preoperative diagnostic radiograph Figure 7: Master cone selection Figure 8: Postoperative radiograph Discussion Missed canals or inadequate cleaning and shaping of the canals leads to failure of root canal treatment. If it is possible to detect the extra canal during the diagnosis stage, it helps the dentist plan the treatment beforehand 5. Endodontic therapy requires a thorough knowledge of root canal morphology to adequately shape and clean the canal system. The internal anatomy of tooth is not always similar. One of the variations that occur in mandibular molars is radix entomolaris, a supernumerary distolingual root. A radix entomolaris was found on the first, second and third mandibular molars, occurring least frequently on the second molar 11. The etiology behind the formation of radix entomolaris is still unclear. In dysmorphic supernumerary roots, its formation could be related to external Figure 6: Working length determination ADR, Vol 1, Issue 1,

6 Radix Entomolaris Hora et al factors during odontogenesis or penetrance of an atavistic gene or polygenetic system 13. Accurate evaluation of diagnostic radiographic views is essential for confirming the number of tooth roots and canals. As radix entomolaris is mostly situated in the same buccolingual plane as the distobuccal root, a superimposition of both roots can appear on the radiograph resulting in an inaccurate diagnosis 2. Taking pre-operative radiograph from two different horizontal angles but the same vertical angle (tube-shift technique), can help in identifying extra canals. To reveal the RE, a second radiograph should be taken from a more mesial or distal angle (30 degrees). 2 An extra canal can be suspected whenever there is an abrupt straightening or loss of radiolucent canal in the pulp cavity. An extra cusp or more prominent occlusal distal or distolingual lobe, in combination with a cervical prominence or convexity, can indicate the presence of an additional root. If an RE or RP is diagnosed before endodontic treatment, one knows what to expect or where to look once the pulp chamber has been opened. 2 The location of the orifice of the root canal of a radix entmolaris has implications for the opening cavity. An extension of the triangular opening cavity to the distolingual results in a more rectangular or trapezoidal outline form. If the radix entmolaris canal entrance is not clearly visible after removal of the pulp chamber roof, a more thorough inspection of the pulp chamber and wall, especially in the distolingual region is necessary 2. Conclusion Knowledge about the basic root canal anatomy and its variations is essential in achieving a higher percentage of success in endodontics. Careful examination of the floor of the pulp chamber reveals clues for locating any extra canals. References 1. Al Nazhan S: Incidence of fourth canal in root canal treated mandibular first molars in a Saudi Arabian sub-population. Int Endod J 1999; 32: Calberson FL, De Moor RJ, Deroose CA: The radix entmolaris and paramolaris: clinical approach in endodontics. J Endod 2007; 33(1): Carlsen O, Alexandersen V: Radix entmolaris: identification and morphology. Scand J Dent Res 1990; 98: Cohen 8 th edition: Tooth morphology and access cavity preparation; De Moor RJG, Deroose CAJG, Calberson FLG: The radix entmolaris in mandibular first molars: an endodontic challenge. Int Endod J 2004; 37: Fabra-Campos H: Three canals in the mesial root of mandibular first permanent molars: a clinical study. Int Endod J 1989; 22: Farooq R, Mushtaq M, Ibrahim M, Rashid A, Khateeb S: Radix entmolaris with a bilateral occurrence; a case series. Internet J Dent Sci 2010; 9 (2): Franklinn S Weine: Initiating endodontic treatment; Gulabivala K, Aung TH, Alavi A, Ng YL: Root and canal morphology of Burmese mandibular molars. Int Endod J 2001; 34: John I Ingle fifth edition endodontics: endodontic cavity preparation; Parolia A, Kundabala M, Thomas MS, Mohan M, Joshi N: Three rooted, four canalled 78 ADR, Vol 1, Issue 1, 2011

7 Hora et al Radix Entomolaris mandibular first molar. Kathmandu Univ Med J 2009; 7(3): Rashid AM, Suliman AA: Incidence of third root in mandibular permanent first molar: an endodontic challenge. Al-Rafidain Dent J 2006; 6(2): Reddy J: The radix entmolaris- an endodontic challenge: case reports. 14. Sert S, Aslanalp V, Tanalp J: Investigation of the root canal configuarations of mandibular permanent teeth in the Turkish population. Int Endod J 2004; 37: Sperber GH, Moreau JL: Study of number of roots and canals in Senegalese first permanent mandibular molars. Int Endod J1998; 31: Vimala N, Firake N: Know your mandibular first molar - A case report. Scientific J 2009; 3 Citation : Hora BS, Garg S, Bhardwaj D, Garg R. Endodontic Management of Radix Entomolaris in First and Third Mandibular Molars with Hybrid Rotary Systems A Case Series. Annals of Dental Research 2011; 1 (1): ADR, Vol 1, Issue 1,