Primosch RE. Anterior supernumerary teeth--assessment and surgical intervention in children. Pediatr Dent. 1981; 3:204-215
Subasioglu A, Savas S, Kucukyilmaz E Genetic background of supernumerary teeth. Eur J Dent. 2015; 9:153-158
Açikgöz A, Açikgöz G, Tunga U, Otan F. Characteristics and prevalence of non-syndrome multiple supernumerary teeth: a retrospective study. Dentomaxillofac. 2006; 35:185-190
Jawad Z, Carmichael F, Houghton N, Bates C. A review of cone beam computed tomography for the diagnosis of root resorption associated with impacted canines, introducing an innovative root resorption scale. Oral Surg Oral Med Oral Pathol. 2016; 122:765-771
Shark teeth: a case of multiple supernumerary teeth Dental Update 2024 14:3, 707-709.
Abstract
A 44-year-old male was referred to the Department of Orthodontics at Manchester Dental Hospital. He presented with pain from his heavily restored, lower right second premolar, which had an apical supplemental tooth, visible radiographically. The dentist queried whether the second premolar tooth could be extracted and the supplemental tooth aligned in its place. Clinical examination revealed no relevant abnormalities. The family and medical history were non-contributory. Panoramic tomography revealed multiple supplemental supernumerary teeth in the canine and premolar regions. Cone beam computed tomography and multidisciplinary team input were required to plan the treatment for this unusual case.
CPD/Clinical Relevance: These findings highlight the management and treatment options for a case of non-syndromic, multiple supernumerary teeth. Consideration must be given to the risk of damage to adjacent structures if surgically removing supernumerary teeth, and the risk that supernumerary teeth may be ankylosed and not amenable to alignment within the arch.
Article
Supernumerary teeth can be single or multiple, unilateral or bilateral in distribution and can occur in one or both jaws. In the permanent dentition, there is a reported prevalence of 0.1–3.8%.1,2,3 Supernumeraries are classified by their morphology (conical, tuberculate, supplemental, odontome) or by their location (mesiodens, paramolar, distomolar). Supplemental supernumerary teeth are defined as those teeth additional to the normal series. They resemble teeth of the normal series and appear at the end of the series.1 The most common supplemental tooth is the permanent maxillary lateral incisor.1
Cases of one or two supernumerary teeth are known to most commonly affect the anterior maxilla. Presentations of multiple supernumerary teeth with no associated systemic conditions or syndromes are uncommon.2 In these cases, supernumerary teeth occur predominantly in the premolar areas, followed by the molar and anterior regions, respectively.2 They are most commonly found in mandibular premolar region.2
The aetiology of supernumerary teeth is not yet fully understood. Several theories have been suggested to explain their existence, but the most common is the ‘hyperactive dental lamina’ theory. This describes a supplemental supernumerary forming from the lingual extension of an accessory tooth bud, and a rudimentary supernumerary develops from epithelial remnants of the lamina dura.4 Genetic factors have also been considered as familial tendenancy has been demonstrated and a sex-linked pattern of inheritance, with males affected twice as often as females.4 Multiple supernumerary teeth are frequently linked to Gardner's syndrome, cleidocranial dysplasia or cleft lip/palate.5
Case report
A 44-year-old male was referred into the Orthodontic Department of the University Dental Hospital of Manchester, complaining of pain from his heavily restored lower right second premolar (LR5). His dentist had noted a supplemental supernumerary on the peri-apical radiograph and queried whether this could be aligned in place of LR5. Medically, the patient was fit and well. He was a regular attender at his general dentist.
Clinical examination revealed a heavily restored dentition, poor oral hygiene and evidence of periodontal disease. The following teeth were present with no evidence of caries or peri-apical pathology: UR8–UL8, LR8, LR7, LR4–LL8.
Orthodontic assessment showed a Class III incisor relationship on a Class I skeletal base with increased vertical proportions. This was complicated by moderate upper and lower labial segment crowding and crossbites localized to UR1, LR1 and UL2, LL3 (Figure 1).
Figure 1.
(a–e) Baseline photos taken with written consent. (Courtesy of the Manchester Dental Hospital Orthodontic Department.)
A panoramic tomograph revealed the following (Figure 2):
Generalized 15–25% horizontal bone loss;
One diminutive supplemental tooth between UR3, 4 and another between UL3, 4;
Supplemental LL3–5 and supplemental LR4, 5;
Possible supernumerary teeth associated with upper central incisors;
A heavily restored LR5 with a post-core crown and defective distal margin;
Heavily restored LR6 with a poorly condensed, short root canal obturation and signs of peri-apical inflammation (unsure whether this was static/healing or active);
Heavily restored LL6.
Figure 2. Panoramic tomograph radiograph showing supernumeraries between UR3, 4 and UL3, 4, supplemental LL3–5 and supplemental LR4, 5, poor prognosis LR5, 6 and LL6 and mild horizontal periodontal bone loss.
A CBCT scan was requested to confirm the three-dimensional location of the supernumerary teeth and whether there was resorption of neighbouring teeth. The CBCT report revealed the following:
In the maxilla, no associated resorption was found on the UL3, UL4. Shallow resorption was suspected on the UR3 (Figure 3). No additional supernumerary teeth were found to be present.
On the right side of the mandible, the distal supernumerary tooth was lying obliquely across the dental arch with the crown lying lingually and the root buccally. It was causing resorption of the lingual aspect of the apical half of the LR5 root (Figure 4). No resorption was noted on LR3, 4.
On the left side of the mandible, three unerupted supplemental teeth were confirmed. Their crowns were lingual to the roots of the erupted teeth. Some root resorption was noted on the lingual aspect of the apical half of the lower left first molar mesial root. The ID canal was found to be 1.5 mm from the root apex of the most distal supernumerary tooth.
Figure 3. Shallow resorption suspected distally on UR3.Figure 4. LR5: resorption on lingual side of apical half of LR5 root, which may also have a root fracture.
The radiologist reported that there was evidence of resorption of the lingual side of the LL6 mesial root (Figure 5), the lingual side of LR5 root and suspected shallow resorption of the UR3 root. However, it was noted that due to the age of the patient, the resorptions were likely to be historical and non-progressive.
Figure 5. Some root resorption on lingual aspect of apical half of the LL6 mesial root.
The following diagnoses were made:
Generalized periodontitis (stage 2 grade B), currently unstable;
Multiple supernumerary teeth;
Suboptimal root canal treatment LR6;
Suspected root fracture LR5.
On further questioning, the patient revealed that he had undergone extensive genetic testing some years earlier, due to a suspicion that the multiple supernumerary teeth were perhaps associated with an undiagnosed syndrome. However, all genetic tests were negative.
The patient attended the multidisciplinary hypodontia clinic at the University Dental Hospital of Manchester for consultation and treatment planning. After careful discussion of the findings, treatment options, risks and benefits with the patient, the following plan was decided:
Extensive oral hygiene instruction;
Non-surgical root surface debridement and 3-monthly dental visits to stabilize his periodontal condition;
Re-root canal treatment for LR6;
Investigation of LR5 if symptoms did not resolve after the LR6 re-root canal treatment;
Monitor supernumerary teeth for cystic changes or signs of progressive resorption.
The patient decided not to undergo orthodontic or surgical treatment, and opted for conservative management as detailed above.
Discussion
If the patient had been keen to pursue more extensive treatment, a suggested orthodontic plan included extraction of UL supplemental, UR supplemental, LR4 supplemental, LR5, +/- LR6 and exposure and bonding of LR5 supplemental tooth to attempt alignment under general anaesthesia. The LL3–5 supplemental crowns were lingual to the erupted teeth and, therefore, buccal torqueing of the LL3–5 erupted teeth could have moved the roots into contact with the supplemental teeth, resulting in resorption. Therefore, consideration of the removal of these supplemental teeth was also justified.
This treatment plan had surgical risks, which included damage to adjacent teeth and nerves, and osseous defects. This had to be weighed against the risk of leaving and monitoring the supernumerary teeth. Monitoring carries the risk of displacement and migration of supernumerary teeth, resorption of neighbouring teeth roots and cystic changes. However, histological evidence of cystic formation occurs in only 4–9% of unerupted supernumerary teeth.4 It has been reported that approximately 75% of supernumerary teeth are asymptomatically impacted and are chance findings on radiographs.6 Given the close proximity of these supernumerary teeth to the mental and inferior dental nerves, and the patient's lack of aesthetic concern regarding his dentition, he decided against surgery.
CBCT is a useful tool to provide additional information regarding the position of supernumerary teeth and evidence of resorption of neighbouring roots. Jawad et al have shown that CBCT can improve the detection rate of resorption related to impacted maxillary canines by 63%.7 CBCTs should, however, only be considered where conventional radiographs fail to provide enough information. These should be considered in cases where impacted teeth are close to important structures and their removal could lead to complications.8 In this case, CBCT was justified, and aided greatly in the decision-making process.
Conclusion
This is an interesting case of a male presenting with multiple supplemental supernumerary teeth, and a previous history of pain from LR5. The pain was likely to be originating from apical pathology associated with a suboptimal root filling in LR6. There was evidence of mild root resorption affecting UR3, LR5, LL6 which, given the patient's age, was likely to be non-progressive. Unusually, the supernumerary teeth were not associated with any syndromes. CBCT imaging for orthodontic and surgical treatment planning can be of benefit in cases of impacted supernumerary teeth. If these teeth are asymptomatic and a patient declines orthodontic treatment, reviewing these patients to monitor for pathological changes may be the treatment plan of choice.
