Talon cusp in Malaysia Rusmah, Meon, BDS(Malaya), MScD(Wales)*
Key words: Developmental anomalies, talon cusp. Abstract Five hundred and thirty-six patientswere examined for the presence of talon cusps. The anomaly was observed in 28 patients (5.2 per cent). There was no sex predilection in the occurrence. Only two patients had a bilateral occurrence, with the maxillary lateral incisors being the most commonly affected. Radiographic evidence of pulpal extension into the cusp was observed in five patients. Many of the affected teeth presented with deep developmental grooves some of which were carious andlor occlusal interference leading to malocclusion. (Received for publication February 1989. Revised January 1990.Accepted April 1990.)
Introduction The talon cusp is a cusp-like structure projecting from the cingulum of maxillary or mandibular incisors.'-4 Mader5 suggested that the term be used only to describe anomalous cusps of permanent incisor teeth that prominently project from the lingual surface of the tooth, are morphologically well delineated and extend at least half the distance from the cemento-enamel junction. Chawla et a1.6 defined the talon cusp as 'a demarcated projection ofone millimetre or more present on the lingual surface of anterior teeth'. A more critical definition was suggested by Davies and They suggested that the definition of talon cusp should be, 'an additional cusp that prominently projects from the lingual surface of primary or permanent anterior teeth, is morphologically well delineated,
*Lecturer in Children's Dentistry, University of Malaya. Australian Dental Journal 1991;36(1):11-14.
and extends at least half the distance from the cemento-enamel junction to the incisal edge'. The shape and length of the cusp varies, and it may extend past the incisal edge of the tooth. A deep developmental groove may be present where the cusp joins the sloping lingual surface of the incisor (Fig. 1). Histological studies have shown that this cusp consists of enamel and dentine with or without a slender extension of pulp from the pulp ~harnber.'.~ Radiographic examination may reveal the presence of this pulpal extension (Fig. 2). The most commonly affected teeth are the permanent maxillary incisors. Morin8 reviewed the literature and observed that 90 per cent of reported cases of talon cusp occurred in the permanent dentition and only 10 per cent in the primary dentition. It can occur in both sexes and may be unilateral or bilateral. These cusps can interfere with speech, occlusion and aesthetics, while the developmental grooves around them are often areas of plaque retention and foci of carious a t t a ~ k . ~ . ~ . ~ . ' O Talon cusp has been reported to occur among Europeans and A s i a n ~ . ' - ~ *However, ~.' there is a paucity of literature on its incidence. This study was undertaken to investigate the incidence of talon cusp among Malaysians.
Materials and ,,.,=hods Five hundred and thirty-six patients of the Department of Children's Dentistry, Faculty of Dentistry, University of Malaya were included in this study. Their ages ranged from seven to thirteen years. These patients had no missing maxillary or mandibular permanent incisors and had adequate radiographic surveys (pantomographs) that showed good dental definition. All erupted incisors were examined for talon cusps. The definition of talon cusp as suggested by Davies and Brook7 was used in assessing the teeth. 11
Fig. 1.-Talon cusp on a lateral maxillary incisor. Note the prominent grooves at the lateral aspects of the cusp. Fig. 2. -Periapical radiograph of a lateral incisor with talon cusp showing pulpal extension into the cusp.
Table 1. Prevalence of talon cusp according to sex Sex
Present"
Total
Male Female Total
12 (5.4) 16 (5.1) 28 (5.2)
222 314 536
When a talon cusp was present, the state of the tubercles were noted, and periapical radiographs were taken to detect the presence of pulpal extensions in to the cusps. T h e presence of other associated dental complications and anomalies in these subjects were also noted.
*Percentage in parenthesis. (x' =0.157, p = 0.5).
Table 2. cusp
Distribution of teeth with talon
Side
Maxillary lateral incisors
Maxillary central incisors
Total
Left Right Total
15 14 29
1 0 1
16 14
12
30
Results T h e prevalence of talon cusp according to sex is shown in Table 1. T h e anomaly was observed in 28 subjects, an overall prevalence of 5.2 per cent. Twelve males (5.4 per cent of males) and 16 females (5.1 per cent of females) had talon cusp. In this study, talon cusp was detected in the permanent maxillary incisors only (Table 2). In most of the patients, talon cusp occurred unilaterally. Of the 28 subjects, only two had a bilateral occurrence. All but one involved the permanent Australian Dental Journal 1991;36:1.
Table 3. Radiographic appearance and associated dental complications and anomalies observed in patients with talon cusp Case
Affected tooth
Radiographic evidence of pulp tissue in cusp
1
11 22 12, 22 22 12,22 12 22 12 12 12 12 22 22 12 12 12 22 12 22 22 22 12 22 22 12 22 12 12
Absent Present Absent Absent Absent Absent Present Absent Absent Present Absent Absent Absent Absent Absent Absent Absent Absent Absent Absent Absent Present Absent Absent Absent Absent Present Absent
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
maxillary lateral incisor. Only one involved the permanent central incisor. Table 3 shows the teeth affected with talon cusp, those with radiographic evidence of pulp tissue in the cusp, and other associated dental complications and anomalies observed in patients with talon cusp. Only five of the talon cusps showed radiographic evidence of pulpal extension into the tubercle. Four of the affected teeth were carious and required restorations while another three had very deep developmental grooves and required prophylactic treatment to prevent the development of caries. Occlusal interference leading to attrition of the cusp with or without lingual displacement of the opposing teeth was observed in seven patients. Few patients had associated dental anomalies. One patient had a dens evaginatus on the second right mandibular premolar while another had a palatal invagination on the contralateral incisor. Discussion T h e exact aetiology of talon cusp is ~ n k n o w n . ' ~Developmentally, ~~~~~' it is a result of an outfolding of the enamel organ during the development of the t o ~ t h . ~ The incidence of talon cusp in this study was Australian Dental Journal 1991;36:1
Associated dental anomalies and complications None Palatal pit on 12 Occlusal interference Carious grooves None Occlusal interference None None Carious grooves None Dens evaginatus on 45 None Carious grooves Occlusal interference None None Deep grooves, occlusal interference None Carious grooves None Deep grooves, occlusal interference Occlusal interference None Occlusal interference Deep grooves None None None
observed to be 5.2 per cent. This appeared to be slightly lower than the incidence previously reported among Indians by Chawla et a1.6 However, this difference should not be interpreted as a disparity due to different samples. The wider criteria used by them and not the differences in samples could be the contributing factor for the disparity in prevalences between the two studies. Another factor to consider is that this study was based on observations made on persons attending for dental treatment in the Dental Faculty. Thus, they might not be a true representation of the occurrence in the general community. Nevertheless, with a prevalence of 5.2 per cent, there is a possibility of the talon cusp which had been considered a rarityL.2is, in reality, a common occurrence among Malaysians. It is even more common than the dens e~aginatus.'~-'~ No significant differences in prevalence of talon cusp on the basis of sex were observed in this study (X2= 0.157, p = 0.5). The anomaly was equally distributed in both sexes. This is in contrast to the finding of Davies and Brook' who reported a sexlinked association in the occurrence of talon cusp based on a review of the literature. The possibility of numerous unreported cases could be the reason for the observed sex-linked association. 13
T h e trait was observed to occur in maxillary incisors only with the lateral incisors more commonly affected than the centrals which is in agreement with previous ~ t u d i e s . ~ . ~No . ' .involve~ ment of the permanent mandibular incisors was observed even though involvement of these teeth has been reported." There are many case reports of patients with talon cusp associated with complications and dental abnorrnalitie~.'.~.~ The principal problem is usually due to its large size and the prominent developmental grooves between the tooth and cusp. The grooves become carious easily and thus require restoration. T h e presence of pulpal extension into the cusp seldom causes pulpal pathosis for, unlike the dens evaginatus, it is seldom fractured or subject to gross attrition which exposes the pulp to infection. Pulpal exposures and the need for endodontic treatment are normally the result of the inevitable significant reduction of the cusps to relieve occlusal interference. Although the talon cusp usually occurs as an isolated finding, review of the literature and reported cases suggest its possible association with other abnormal somatic and dental finding^.^.'^ Two of the 28 patients with talon cusp in this study were observed to exhibit co-existing dental anomalies; one had a dens evaginatus on the second right mandibular premolar, while another had a palatal invagination on the contralateral tooth. This finding is possibly related to the fact that all three are developmental abnormalities. Talon cusp and dens evaginatus are the result of an outfolding of the enamel organ while the palatal invagination is the result of the infolding of the enamel organ during development of the tooth. T h e exact mechanism that leads to this phenomenon is still unknown. Conclusion The prevalence of talon cusp among this group of Malaysians was found to be 5.2 per cent with no significant difference between males and females. The anomaly mostly occurred unilaterally and only
14
maxillary incisors were affected. Radiographically it is not always possible to identify the pulpal extension into the cusp. Its presence may or may not cause dental problems or be associated with other dental abnormalities.
References 1. Mellor JK, Ripa LW. Talon cusp: a clinically significant
anomaly. Oral Surg Oral Med Oral Path 1970;29:225-8. 2. Shafer WG, Hine MK, Levy BM. A textbook of oral pathology. 4th edn. Philadelphia: WB Saunders, 1983:40. 3. Shey Z, Eytel R. Clinical management of an unusual case of dens evaginatus in a maxillary central incisor. J Am Dent ASSOC1983; 106~346-8. 4. Gardner DG, Girgis SS. Talon cusp, a dental anomaly in the Rubinstein-Taybi Syndrome. Oral Surg Oral Med Oral Path 1979;47:519-21. 5. Mader CL. Talon cusp. J Am Dent Assoc 1981;103:244-6. 6. Chawla HS, Tewari A, Gopalakrishnan NS. Talon cusp a prevalence study. J Ind SOCPedod Prev Dent 1983; 1:28-34. 7. Davies PJ, Brook AH. The presentation of talon cusp: diagnosis, clinical features, associations and possible aetiology. Br Dent J 1986;160:84-8. 8. Morin CK. Talon cusp affecting the primary maxillary central incisors: report of case. J Dent Child 1987;54:283-5. 9. Pitts DL, Hall SH. Talon cusp management: orthodonticendodontic considerations. J Dent Child 1983;50:364-8. 10. Natkins E, Pitts DL, Worthington PA. A case of talon cusp associated with other odontogenic abnormalities. J Endod 1983;9:49 1-5. 11. Mader CL. Mandibular talon cusp. J Am Dent Assoc 1982;105:651-3. 12. Yip WK. The prevalence of dens evaginatus. Oral Surg Oral Med Oral Path 1974;38:80-7. 13. Lau T C . Odontomes of the axial core type. Br Dent J 1955;99:219-25. 14. Reichart P, Tantiniran D. Dens evaginatus in the Thai. Oral Surg Oral Med Oral Path 1975;39:615-21. 15. Goldstein E, Medina JL. Mohr Syndrome or oral-facialdigital 11; report of 2 cases. J Am Dent Assoc 1974;89:377-82.
Address for correspondenceheprints: Department of Children's Dentistry, Faculty of Dentistry, University of Malaya, 59100 Kuala Lumpur, Malaysia.
Australian Dental Journal 1991;36:1,
Key words: Developmental anomalies, talon cusp. Abstract Five hundred and thirty-six patientswere examined for the presence of talon cusps. The anomaly was observed in 28 patients (5.2 per cent). There was no sex predilection in the occurrence. Only two patients had a bilateral occurrence, with the maxillary lateral incisors being the most commonly affected. Radiographic evidence of pulpal extension into the cusp was observed in five patients. Many of the affected teeth presented with deep developmental grooves some of which were carious andlor occlusal interference leading to malocclusion. (Received for publication February 1989. Revised January 1990.Accepted April 1990.)
Introduction The talon cusp is a cusp-like structure projecting from the cingulum of maxillary or mandibular incisors.'-4 Mader5 suggested that the term be used only to describe anomalous cusps of permanent incisor teeth that prominently project from the lingual surface of the tooth, are morphologically well delineated and extend at least half the distance from the cemento-enamel junction. Chawla et a1.6 defined the talon cusp as 'a demarcated projection ofone millimetre or more present on the lingual surface of anterior teeth'. A more critical definition was suggested by Davies and They suggested that the definition of talon cusp should be, 'an additional cusp that prominently projects from the lingual surface of primary or permanent anterior teeth, is morphologically well delineated,
*Lecturer in Children's Dentistry, University of Malaya. Australian Dental Journal 1991;36(1):11-14.
and extends at least half the distance from the cemento-enamel junction to the incisal edge'. The shape and length of the cusp varies, and it may extend past the incisal edge of the tooth. A deep developmental groove may be present where the cusp joins the sloping lingual surface of the incisor (Fig. 1). Histological studies have shown that this cusp consists of enamel and dentine with or without a slender extension of pulp from the pulp ~harnber.'.~ Radiographic examination may reveal the presence of this pulpal extension (Fig. 2). The most commonly affected teeth are the permanent maxillary incisors. Morin8 reviewed the literature and observed that 90 per cent of reported cases of talon cusp occurred in the permanent dentition and only 10 per cent in the primary dentition. It can occur in both sexes and may be unilateral or bilateral. These cusps can interfere with speech, occlusion and aesthetics, while the developmental grooves around them are often areas of plaque retention and foci of carious a t t a ~ k . ~ . ~ . ~ . ' O Talon cusp has been reported to occur among Europeans and A s i a n ~ . ' - ~ *However, ~.' there is a paucity of literature on its incidence. This study was undertaken to investigate the incidence of talon cusp among Malaysians.
Materials and ,,.,=hods Five hundred and thirty-six patients of the Department of Children's Dentistry, Faculty of Dentistry, University of Malaya were included in this study. Their ages ranged from seven to thirteen years. These patients had no missing maxillary or mandibular permanent incisors and had adequate radiographic surveys (pantomographs) that showed good dental definition. All erupted incisors were examined for talon cusps. The definition of talon cusp as suggested by Davies and Brook7 was used in assessing the teeth. 11
Fig. 1.-Talon cusp on a lateral maxillary incisor. Note the prominent grooves at the lateral aspects of the cusp. Fig. 2. -Periapical radiograph of a lateral incisor with talon cusp showing pulpal extension into the cusp.
Table 1. Prevalence of talon cusp according to sex Sex
Present"
Total
Male Female Total
12 (5.4) 16 (5.1) 28 (5.2)
222 314 536
When a talon cusp was present, the state of the tubercles were noted, and periapical radiographs were taken to detect the presence of pulpal extensions in to the cusps. T h e presence of other associated dental complications and anomalies in these subjects were also noted.
*Percentage in parenthesis. (x' =0.157, p = 0.5).
Table 2. cusp
Distribution of teeth with talon
Side
Maxillary lateral incisors
Maxillary central incisors
Total
Left Right Total
15 14 29
1 0 1
16 14
12
30
Results T h e prevalence of talon cusp according to sex is shown in Table 1. T h e anomaly was observed in 28 subjects, an overall prevalence of 5.2 per cent. Twelve males (5.4 per cent of males) and 16 females (5.1 per cent of females) had talon cusp. In this study, talon cusp was detected in the permanent maxillary incisors only (Table 2). In most of the patients, talon cusp occurred unilaterally. Of the 28 subjects, only two had a bilateral occurrence. All but one involved the permanent Australian Dental Journal 1991;36:1.
Table 3. Radiographic appearance and associated dental complications and anomalies observed in patients with talon cusp Case
Affected tooth
Radiographic evidence of pulp tissue in cusp
1
11 22 12, 22 22 12,22 12 22 12 12 12 12 22 22 12 12 12 22 12 22 22 22 12 22 22 12 22 12 12
Absent Present Absent Absent Absent Absent Present Absent Absent Present Absent Absent Absent Absent Absent Absent Absent Absent Absent Absent Absent Present Absent Absent Absent Absent Present Absent
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
maxillary lateral incisor. Only one involved the permanent central incisor. Table 3 shows the teeth affected with talon cusp, those with radiographic evidence of pulp tissue in the cusp, and other associated dental complications and anomalies observed in patients with talon cusp. Only five of the talon cusps showed radiographic evidence of pulpal extension into the tubercle. Four of the affected teeth were carious and required restorations while another three had very deep developmental grooves and required prophylactic treatment to prevent the development of caries. Occlusal interference leading to attrition of the cusp with or without lingual displacement of the opposing teeth was observed in seven patients. Few patients had associated dental anomalies. One patient had a dens evaginatus on the second right mandibular premolar while another had a palatal invagination on the contralateral incisor. Discussion T h e exact aetiology of talon cusp is ~ n k n o w n . ' ~Developmentally, ~~~~~' it is a result of an outfolding of the enamel organ during the development of the t o ~ t h . ~ The incidence of talon cusp in this study was Australian Dental Journal 1991;36:1
Associated dental anomalies and complications None Palatal pit on 12 Occlusal interference Carious grooves None Occlusal interference None None Carious grooves None Dens evaginatus on 45 None Carious grooves Occlusal interference None None Deep grooves, occlusal interference None Carious grooves None Deep grooves, occlusal interference Occlusal interference None Occlusal interference Deep grooves None None None
observed to be 5.2 per cent. This appeared to be slightly lower than the incidence previously reported among Indians by Chawla et a1.6 However, this difference should not be interpreted as a disparity due to different samples. The wider criteria used by them and not the differences in samples could be the contributing factor for the disparity in prevalences between the two studies. Another factor to consider is that this study was based on observations made on persons attending for dental treatment in the Dental Faculty. Thus, they might not be a true representation of the occurrence in the general community. Nevertheless, with a prevalence of 5.2 per cent, there is a possibility of the talon cusp which had been considered a rarityL.2is, in reality, a common occurrence among Malaysians. It is even more common than the dens e~aginatus.'~-'~ No significant differences in prevalence of talon cusp on the basis of sex were observed in this study (X2= 0.157, p = 0.5). The anomaly was equally distributed in both sexes. This is in contrast to the finding of Davies and Brook' who reported a sexlinked association in the occurrence of talon cusp based on a review of the literature. The possibility of numerous unreported cases could be the reason for the observed sex-linked association. 13
T h e trait was observed to occur in maxillary incisors only with the lateral incisors more commonly affected than the centrals which is in agreement with previous ~ t u d i e s . ~ . ~No . ' .involve~ ment of the permanent mandibular incisors was observed even though involvement of these teeth has been reported." There are many case reports of patients with talon cusp associated with complications and dental abnorrnalitie~.'.~.~ The principal problem is usually due to its large size and the prominent developmental grooves between the tooth and cusp. The grooves become carious easily and thus require restoration. T h e presence of pulpal extension into the cusp seldom causes pulpal pathosis for, unlike the dens evaginatus, it is seldom fractured or subject to gross attrition which exposes the pulp to infection. Pulpal exposures and the need for endodontic treatment are normally the result of the inevitable significant reduction of the cusps to relieve occlusal interference. Although the talon cusp usually occurs as an isolated finding, review of the literature and reported cases suggest its possible association with other abnormal somatic and dental finding^.^.'^ Two of the 28 patients with talon cusp in this study were observed to exhibit co-existing dental anomalies; one had a dens evaginatus on the second right mandibular premolar, while another had a palatal invagination on the contralateral tooth. This finding is possibly related to the fact that all three are developmental abnormalities. Talon cusp and dens evaginatus are the result of an outfolding of the enamel organ while the palatal invagination is the result of the infolding of the enamel organ during development of the tooth. T h e exact mechanism that leads to this phenomenon is still unknown. Conclusion The prevalence of talon cusp among this group of Malaysians was found to be 5.2 per cent with no significant difference between males and females. The anomaly mostly occurred unilaterally and only
14
maxillary incisors were affected. Radiographically it is not always possible to identify the pulpal extension into the cusp. Its presence may or may not cause dental problems or be associated with other dental abnormalities.
References 1. Mellor JK, Ripa LW. Talon cusp: a clinically significant
anomaly. Oral Surg Oral Med Oral Path 1970;29:225-8. 2. Shafer WG, Hine MK, Levy BM. A textbook of oral pathology. 4th edn. Philadelphia: WB Saunders, 1983:40. 3. Shey Z, Eytel R. Clinical management of an unusual case of dens evaginatus in a maxillary central incisor. J Am Dent ASSOC1983; 106~346-8. 4. Gardner DG, Girgis SS. Talon cusp, a dental anomaly in the Rubinstein-Taybi Syndrome. Oral Surg Oral Med Oral Path 1979;47:519-21. 5. Mader CL. Talon cusp. J Am Dent Assoc 1981;103:244-6. 6. Chawla HS, Tewari A, Gopalakrishnan NS. Talon cusp a prevalence study. J Ind SOCPedod Prev Dent 1983; 1:28-34. 7. Davies PJ, Brook AH. The presentation of talon cusp: diagnosis, clinical features, associations and possible aetiology. Br Dent J 1986;160:84-8. 8. Morin CK. Talon cusp affecting the primary maxillary central incisors: report of case. J Dent Child 1987;54:283-5. 9. Pitts DL, Hall SH. Talon cusp management: orthodonticendodontic considerations. J Dent Child 1983;50:364-8. 10. Natkins E, Pitts DL, Worthington PA. A case of talon cusp associated with other odontogenic abnormalities. J Endod 1983;9:49 1-5. 11. Mader CL. Mandibular talon cusp. J Am Dent Assoc 1982;105:651-3. 12. Yip WK. The prevalence of dens evaginatus. Oral Surg Oral Med Oral Path 1974;38:80-7. 13. Lau T C . Odontomes of the axial core type. Br Dent J 1955;99:219-25. 14. Reichart P, Tantiniran D. Dens evaginatus in the Thai. Oral Surg Oral Med Oral Path 1975;39:615-21. 15. Goldstein E, Medina JL. Mohr Syndrome or oral-facialdigital 11; report of 2 cases. J Am Dent Assoc 1974;89:377-82.
Address for correspondenceheprints: Department of Children's Dentistry, Faculty of Dentistry, University of Malaya, 59100 Kuala Lumpur, Malaysia.
Australian Dental Journal 1991;36:1,
