| Abstract|| |
The dental literature contains a small number of reports of primary multi-rooted anomalies. Among these reports the majority are regarding three-rooted primary mandibular second molar anomalies. The presence of bilateral three-rooted primary mandibular first and second molars is uncommon. There have been no reports of three-rooted primary molars from India. Here, we present a case of an 8-year-old boy with bilateral three-rooted primary mandibular first and second molars.
Keywords: Three-rooted mandibular molar, dental anomalies, primary first molars, primary second molars
|How to cite this article:|
Ramamurthy N, Srinivasan I. Bilateral three-rooted primary lower molars. Indian J Dent Res 2012;23:700
The prevalence of dental anomalies is lower in the primary dentition than in the permanent dentition. , Specifically, there are fewer reports of primary radicular anomalies than of permanent radicular anomalies. The dental literature reveals several cases of three-rooted mandibular molars in permanent dentition  . Tratman  found that three-rooted mandibular molars were rarer in the primary dentition than in the permanent dentition. There are overall seven studies reported. There have been no reports of three-rooted primary molars from India. This paper presents a case of bilateral three-rooted primary mandibular molars in an 8-year-old boy.
| Case History|| |
An 8-year-old male patient reported to the department of Pedodontics and Preventive Dentistry, M.R Ambedkar Dental College, Bangalore, India, with the chief complaint of pain in the lower left quadrant. His medical and dental history was not significant. An intraoral examination revealed extensive caries in relation to the mandibular left first molar. An intraoral periapical radiograph (IOPA) was advised, which revealed three roots for both the first and second molars [Figure 1]. Similar finding was suspected on the opposite side and an IOPA was again advised, which confirmed the suspicion [Figure 2]. The additional third root was in a midlingual position in the mandibular left first molar and in a distolingual position in the mandibular left second molar and right first and second molars. The mandibular left first molar was extracted [Figure 3]. A fixed band-and-loop space maintainer was planned following the extraction.
|Figure 1: Intraoral periapical radiograph showing primary mandibular left first and second molars with additional root (arrow)|
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|Figure 2: Intraoral periapical radiograph showing primary mandibular right first and second molars with additional root (arrow)|
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|Figure 3: Photographs of extracted primary mandibular left first molar with additional root (arrow) taken from different angles|
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| Discussion|| |
The rarity of reports of anomalous root patterns in primary teeth may not reflect the real situation. This is because there is only a limited time between formation and resorption when radiography can reveal their presence. In many cases, when primary teeth are extracted, root resorption has already removed the evidence. 
Accessory roots form in a similar fashion to normal roots, i.e., as a result of the ingrowth of processes from the root sheath of Hertwig.  Three-rooted lower molars result either from a bifurcated distal root or an accessory distolingual root. Tratman  suggested that the additional root is not simply a division of the distal root but, rather, is a true extra root with a separate orifice and apex.
There have been several reports on the occurrence of three-rooted primary mandibular second molar anomalies but the presence of bilateral three-rooted primary first and second molars is unusual. There have been no reports of three-rooted primary molars from India.
Mann et al. reported a 5-year-old 15 th century American Indian child who presented with a three-rooted primary mandibular second molar. Mayhall  reported a case of a three-rooted permanent mandibular first molar along with a three-rooted primary mandibular second molar in an 8-year-old Chinese child born in Hong Kong. Winkler and Ahmad  have described multi-rooted anomalies in the primary dentition of Native Americans. Jorgensen  reported 7 cases of an additional root in 1041 primary mandibular second molars extracted from Danish patients. Tu et al. reported that 5% of Taiwanese subjects had three-rooted mandibular primary first molars, and that 80% of such teeth occurred unilaterally. Liu et al. described the prevalence of three-rooted anomalies in the primary lower second molars in Chinese patients. Tratman found no additional root in samples collected from Europe and India, but found an additional root in 3 of 42 second primary molars from Japanese subjects. A Japanese radiographic study revealed that 5.6% of 1408 samples of mandibular first primary molars had an additional distolingual root. 
In this patient, we extracted the left primary first molar due to extensive caries extending to the furcation area. During exodontic procedures, the clinician should make sure that the crown of the premolar is not trapped in the interradicular area of the primary tooth as this could cause accidental removal of the developing permanent tooth. The clinician also should inspect extracted anomalous primary teeth to ensure that all roots have been retrieved.
| Conclusion|| |
The knowledge of the anatomy of human teeth and its variations is very important. Failure of therapy may result if the presence of a three-rooted anomaly is not recognized, whatever the treatment being performed - an exodontic or an endodontic procedure.
| References|| |
|1.||Barker BC. Dental anthropology: Some variations and anomalies in human tooth form. Aust Dent J 1973;18:132-40. |
|2.||Curzon MEJ, Curzon JA. Three-rooted mandibular molars in the Keewatin Eskimo: Its relationship to the prevention and treatment of caries. J Can Dent Assoc 1972;38:152-4. |
|3.||Winkler MP, Ahmad R. Multirooted anomalies in the primary Dentition of Native Americans. J Am Dent Assoc 1997;128:1009-11. |
|4.||Tratman EK. Three-rooted lower molars in man and their racial distribution.Br Dent J 1938;64:264-74. |
|5.||Kavanagh C, O'Sullivan VR. A four-rooted primary upper second molar.Int J Paediatr Dent1998;8:279-82. |
|6.||Kovacs I. Contribution to the ontogenetic morphology of roots of human teeth. J Dent Res1967;46:865-74. |
|7.||Mann RW, Dahlberg AA, Stewart TD. Anomalous morphologic formation of deciduous and permanent teeth in a 5-year-old 15 th century child: A variant of the Ekman- Westborg-Julinsyndrome. Oral SurgOral Med Oral Pathol 1990;70:90-4. |
|8.||Mayhall JT.Three-rooted deciduous mandibular second molars.J Can Dent Assoc 1981;47:319-21. |
|9.||Jorgensen KD. The deciduous dentition: A descriptive and comparative anatomical study. ActaOdontolScand 1956;14:201-2. |
|10.||Tu MG, Liu JF, Dai PW,Chen SY, Hsu JT, Huang HL. Prevalence of three-rooted primary mandibular first molars in Taiwan. J Formos Med Assoc 2010;109:69-74. |
|11.||Liu JF, Dai PW, Chen SY, Huang HL, Hsu JT, Chen WL, et al. Prevalence of 3-RootedPrimaryMandibular Second Molars among Chinese Patients. Pediatr Dent 2010;32:123-6. |
|12.||Song JS,Kim SO, Choi BJ,Choi HJ, Son HK, Lee JH. Incidence and relationship of an additional root in the mandibular first permanent molar and primary molars. Oral Surg Oral Med Oral Pathol Oral RadiolEndod 2009;10:e56-60. |
Department of Pedodontics, M.R. Ambedkar Dental College, Bangalore, Karnataka
Source of Support: None, Conflict of Interest: None
[Figure 1], [Figure 2], [Figure 3]