|Year : 2012 | Volume
| Issue : 2 | Page : 83-85
Rare occurrence of bilaterally impacted mandibular supernumerary teeth
Vinay Kumar Bhardwaj1, Jai Ram Kaundal2, Anil Chug3, Sanjeev Vaid2, Abhishek Soni3, Mohinder Chandel3
1 Department of Public Health Dentistry, H.P. Government Dental College and Hospital, Shimla, Himachal Pradesh, India
2 Department of Orthodontics and Dentofacial Orthopaedics, H.P. Government Dental College and Hospital, Shimla, Himachal Pradesh, India
3 Department of Oral and Maxillofacial Surgery, H.P. Government Dental College and Hospital, Shimla, Himachal Pradesh, India
|Date of Web Publication||3-Sep-2012|
Vinay Kumar Bhardwaj
Department of Public Health Dentistry, H.P. Government Dental College and Hospital, Shimla, Himachal Pradesh- 171 001
Source of Support: None, Conflict of Interest: None
Introduction: Supernumerary teeth are present in addition to the normal complement of teeth in permanent or deciduous dentitions. Incidence is high in permanent dentition, affects both the gender. They are more common in males, with the male to female ratio of 2:1. When the supernumerary teeth are causing problems such as, extensive resorption of adjacent teeth, hindering the eruption or malposition of permanent teeth, early surgical intervention is recommended. Case Report: A case of bilaterally impacted supernumerary premolars was reported when an orthopentomograph view was taken which revealed the presence of additional teeth impacted in relation to 35-36 and 45-46. Surgical removal was done as they were resorbing the roots of teeth in their vicinity. Discussion: Literature reports increased occurrence of the supernumeraries in the maxilla but supernumerary premolars are more likely to develop in the mandible. Etiology of supernumerary teeth is ambiguous and is due to following conditions:atavism or reversion, heredity, aberrations during embryologic formation, progress zone, and unified etiologic explanation.
Keywords: Bilaterally impacted, mandibular arch, premolars, supernumerary, supplemental
|How to cite this article:|
Bhardwaj VK, Kaundal JR, Chug A, Vaid S, Soni A, Chandel M. Rare occurrence of bilaterally impacted mandibular supernumerary teeth. Dent Hypotheses 2012;3:83-5
| Introduction|| |
Supernumerary teeth are present in addition to the normal complement of teeth in permanent/deciduous dentitions.  Their incidence is high in permanent dentition, affecting both the gender, but is more common in males, with a male to female ratio of 2:1.  These occur in 0.3-3.8% of the population, of which 90-98% are seen in the maxilla. These may be present singly or in multiples, unilaterally or bilaterally in the maxilla, the mandible or both and are commonly seen in the incisor region of the maxillary arch.  Supernumerary premolars represent between 8%  and 9.1%  of all supernumerary teeth. They are more likely to develop in the mandible than in the maxilla. Supernumerary premolars occur three times more frequently in males than in females, indicating a sex-linked inheritance, with the highest frequency of occurrence in the mandibular premolar region (74%). They are also the most common supernumerary teeth in the mandibular arch.  Seventy-five per-cent of these teeth are impacted, unerupted and generally asymptomatic, and the majority are of the supplemental type.  Bodin, Julin and Thomsson  reported that only 2% of the supernumerary premolars exhibited any pathological changes, and indicated that these teeth should be left untreated rather than risk surgical damage. Removal of unerupted supernumeraries involves the risk of damage to the adjacent structures, and a decision should be made whether to remove or monitor them.  Early surgical intervention is recommended when the supernumerary is causing problems such as, extensive resorption of adjacent teeth, hindering the eruption or malposition of permanent teeth. This article reports a case of bilaterally impacted supernumerary premolars where their surgical removal had to be carried out as they were resorbing the roots of the second premolars and first molars in their vicinity.
| Case Report|| |
A 22-year-old female patient reported to the comprehensive oral care clinic, Department of Public Health Dentistry, with a chief complaint of a hard and painless protuberance since the last 2 months on the tongue side of both sides of the back lower teeth. Family, medical and dental histories were non-contributory. Extra-oral examination was normal. On palpation, a hard, immobile, painless swelling was observed on the lingual aspect of the mandible between 35-36 and 45-46. An orthopentomomograph view was taken, which revealed the presence of an additional tooth impacted in relation to 35-36 and 45-46 [Figure 1]. After the clinical and radiographic evaluations, the condition was diagnosed as an impacted supernumerary tooth. The supernumerary teeth were extracted under local anesthesia because they were causing the resorption of the root of 35, 45 and the mesial root of 36 and 46. Both the extracted teeth resembled a fully formed mandibular premolar [Figure 2].
|Figure 1: Orthopentomogram showing bilaterally impacted supernumerary teeth|
Click here to view
| Discussion|| |
Cases of bilateral supplemental premolar teeth developing later than their counterparts have been reported in the literature. Reports have demonstrated that supernumerary premolar teeth develop approximately 7-11 years after normal development, and it appears likely that this case may be a similar example. Scanlan  et al, reported a similar case in which the supernumerary premolar had led to the resorption of an adjacent tooth. Although the literature reports an increased occurrence of the supernumeraries in the maxilla,  supernumerary premolars are more likely to develop in the mandible.  The etiology of supernumerary teeth is ambiguous, with different factors giving rise to different types of supernumeraries and combined etiological factors responsible for same. Various theories have been suggested to explain this phenomenon,  which are as follows:
(A) Atavism or reversion (B) Heredity (C) Aberrations during embryologic formation(D) Progress zone (E) Unified etiologic explanation.
Atavism or reversion
This hypothesis proposes a reversion to an ancestral human dentition that contained a larger number of teeth.  It has been proposed that a supernumerary premolar may be an atavistic reappearance of the extra premolar of the primitive dentition.
Supernumerary teeth are theorised to result from mutant genes. This is supported by the observation of a greater frequency of supernumerary teeth in patients with maxillofacial anomalies such as  cleidocranial dysostosis, cleft lip or cleft palate and Gardner's syndrome. It has also been proposed that autosomal inheritance with lack of penetration might also give rise to supernumerary teeth. 
There are several theories that are based on aberrations during embryologic formation. They include theory of epithelial remnants, theory of supernumerary dental germs and theory of duplication by dichotomy of tooth germs, theory of additional proliferation of the dental lamina and theory of histochemical disruption. 
This theory proposed that supernumerary teeth result from the progress zone of the dental lamina in the end of every tooth series. 
Unified etiologic explanation
This theory suggests a unified etiology for anomalies of tooth number and size. It is based on a multifactorial model that has a continuous scale, with thresholds related to a spectrum of tooth number and size. Oehlers suggested that supplemental premolars were formed from an extension of the dental lamina in the region.  He cited that the accessory buds may possibly represent members of post-permanent dentition. Supernumerary teeth usually cause dental abnormalities except in cases of deeply buried asymptomatic teeth. These teeth should be reviewed periodically.
Supernumerary teeth may be classified according to:
- Morphology: Rudimentary and supplemental. Rudimentary teeth are smaller and tuberculate in shape,  whereas the supplemental teeth usually resemble the teeth of a group with which they are associated, i.e. incisors, canines, premolars and molars.
- Number: Single or multiple.
- Location: Mesiodens, paramolar, distomolar.
Supernumeraries generally cause problems of malocclusion of a local nature, like tipping of adjacent teeth, rotation, bodily displacement, delayed eruption or prevent eruption of tooth of normal series. Also, they may lead to aesthetic disharmony and functional distortion.
The treatment options include:
- Maintain in situ with regular follow-up.
- Extraction if accompanied by pathologic changes.
- Orthodontic treatment.
In this case, the supernumerary teeth had resorbed the roots of 35, 45 and mesial root of 36, 46; hence, they were extracted. These supernumerary teeth were categorized as supplemental as the morphology of the extracted supernumerary teeth resembled the mandibular premolar with which they were associated, i.e. 35 and 45, and were of a normal size and shape with fully formed crown and root. 
| Acknowledgments|| |
The authors would like to thank the administration of the Dental College and Hospital Shimla and Librarian, Smt. Anita Dhiman, for their timely support.
| References|| |
|1.||Shafer WG. Developmental disturbance in shape of teeth. In: Shafer WG, Hine MK, Levy BM, editors. A textbook of oral pathology. 4 th ed. Tokyo: W. B. Sunders; 1983. p. 42-4. |
|2.||Alvarez I, Creath CJ. Radiographic considerations for supernumerary tooth extractions: report of case. ASDC J Dent Child 1995;62:141-4. |
|3.||Zhu JF, Marcushamer M, King DL, Henry RJ. Supernumerary and congenitally absent teeth: a literature review. J Clin Pediatr Dent 1996;20:87-95. |
|4.||Nazif MM, Ruffalo RC, Zulo T. Impacted supernumerary Teeth: A survey of 50 cases. J Am Dent Assoc 1983;106:201-4. |
|5.||Grahnen J, Lindahl BC. Supernumerary teeth in the permanent dentition: A frequency study. Odontol Revy 1961;12:290-4. |
|6.||Solares R, Romero MI. Supernumerary premolars: a literature review. Pediatr Dent 2004;26:450-8. |
|7.||Bodin I, Julin P, Thomsson M. Hyperdontia I. Frequency and distribution of supernumerary teeth among 21,609 patients. Dentomaxillofac Radiol 1978;7:15-7. |
|8.||Bowden DE. Post-permanent dentition in the premolar region. Br Dent J 1971;131:113-6. |
|9.||Scanlan PJ, Hodges SJ. Supernumerary premolar teeth in siblings. Br J Orthod 1997;24:297-300. |
|10.||Dash JK, Sahoo PK, Das S, Mohanty UK. Prevalence of supernumerary teeth in deciduous and mixed dentition. J Indian Soc Pedod Prev Dent 2003;21:37-41. |
|11.||Stafne EC. Supernumerary Teeth. Dental Cosmos 1932;74:653-9. |
|12.||Grimanis GA, Kyriakides AT, Spyropoulus ND. A survey on supernumerary molars. Quintessence Int 1991;22:989-95. |
|13.||Gardiner JH. Supernumerary teeth. Dent Pract 1961;12:63-73. |
|14.||Angelopoulos AP. In: Textbook of Oral Pathology (in Greek). Athens: Medical Publications Litsas; 1976. p. 163. |
|15.||Zvolanek JW, Spotts TM. Supernumerary mandibular premolars, report of cases. J Am Dent Assoc 1985;110:721-3. |
|16.||Fisher SE. Maxillary sixth molars. Br Dent J 1982;152:356. |
|17.||Schwartz JH. Supernumerary teeth in anthropoid primates and models of tooth development. Arch Oral Biol 1984;29:833-42. |
|18.||Oehlers FA. Postpermanent premolars. Br Dent J 1952;93:157-8. |
|19.||Bhaskar SN. Synopsis of oral pathology. St. Louis: CV. Mosby; 1991. p. 17. |
|20.||Braham LR, Morris ME. Text Book of pediatric dentistry. 2 nd ed. CBS Publishers: New Delhi; 1990. p. 99-415. |
[Figure 1], [Figure 2]