C A S E R E P O RT
Diagnosis and management of a maxillary lateral incisor exhibiting dens invaginatus and dens evaginatus
Harry Francis Akers,BDSc,FRACDS,BA,FICD,FPFA,FADI,GCertDent,GDipClinDent,PhD,GCertHE;
Carolyn Mary Henderson,BDSc,MDSc; and Michael Anthony Foley,BDSc,FADI,PFPA,FICD,MPH,MEpi Brisbane Dental Hospital, Queensland Health, Brisbane, Queensland, Australia
Keywords
dens evaginatus, dens invaginatus, fusion.
Correspondence
Dr Harry Francis Akers, Unit 1, ‘Karinya Terraces’, 31 Foxton Street, Indooroopilly, Brisbane, Qld 4068, Australia. Email:
hak52691@bigpond.net.au
doi:10.1111/aej.12056
Declaration: In accordance with the principles enunciated in the Declaration of Helsinki (revised 2004), parental and patient approval for publishing this report was sought and achieved. The authors adhered to QH’s protocol for consent to treatment and release of records. The authors, employees of QH, applied to The Royal Brisbane and Women’s Hospital Human Ethics Committee for permission to publish the manuscript.
Approval was granted. The report attracted neither grant nor funding. The authors declare no financial interest.
Abstract
This case report, involving an indigenous Australian, presents the diagnosis and non-surgical endodontic management of a 22 with developmental abnor- malities. They include a dens evaginatus and a dens invaginatus that extends to an apical burst in a second truncated root. Cone-beam computed tomogra- phy and endodontic microscopy were not available to the clinician. This case report focuses on ambiguities appearing in the literature relating to classifica- tion and terminology associated with the abovementioned developmental anomalies. It also demonstrates the need to methodically collect and cautiously interpret available information before initiating endodontic intervention. Axial inclination, distance perception, internal demarcation and spatial awareness, together with an understanding of dental anatomy, embryology and histology and associated physiology and pathology, allowed the clinician to accurately predict the point, the angle and the depth of coronal access. Sensibility of the dentino-pulpal complex was maintained. Critical thinking, experience, inno- vation, problem-solving and established principles can compensate for inac- cessible technologies.
Introduction
This case report presents the diagnosis and non-surgical endodontic management of a 22 with multiple develop- mental abnormalities. They include a dens evaginatus (DE) and a dens invaginatus (DI) that extends to an apical burst in a second truncated root. To the authors’ knowl- edge, this is the first documented case of DI and DE in an indigenous Australian. The innovative aspect of treatment is that the clinician, a specialist endodontist, maintained sensibility in the seemingly autonomous dentino-pulpal system. This phenomenon has been reported only once in the Australian endodontic literature and rarely in the international equivalent (1). Successful treatment was achieved without the aid of cone-beam computed tomography (CBCT) and endodontic micros- copy. From the academic perspective, this case report exposes ambiguities appearing in the literature relating to classification systems and associated terminologies for the abovementioned developmental anomalies. From the
general practitioner’s view, it demonstrates the role of a specialist’s experience in the preamble to endodontic diagnosis and intervention.
Critical thinking requires careful observation, effective analysis and objective judgment. With regard to the diag- nosis, the clinician methodically collected and assessed evidence from the clinical examination, radiographs and special tests. This information, augmented by the clini- cian’s knowledge of dental anatomy, embryology and histology, together with an understanding of associated physiology and pathology, allowed a provisional diagno- sis. Paradoxically, a definitive diagnosis was elusive and largely irrelevant to treatment. With regard to the inter- vention, the clinician engaged difficult-to-learn concepts, namely, axial inclination, distance perception, internal demarcation and spatial awareness, to initiate the bio- mechanical phases of endodontic treatment. In unusual cases, clinical experience and the ability to think critically and analytically can often compensate for inaccessible technologies.
Aust Endod J 2014; 40: 32–38
The literature relating to anomalous development of tooth number, size, shape and structure has notable fea- tures. Having a genesis in the 1950s, an era when endodontics was a young discipline, debates regarding definitions and systems for classification have generated a consensus regarding terminologies. Some early terms and definitions, for example, DI ‘an infolding of the crown’;
DE ‘an anomalous outgrowth of tooth structure’ and;
fusion ‘a “double” tooth resulting from the union of two adjacent tooth germs’, appear in the American Associa- tion of Endodontists’ Glossary of Endodontic Terms (2).
However, anomalous dental development is an umbrella term that embraces many entities with an extensive range of morphologies. Classification systems and associ- ated terminologies describe the developmental origins and ignore the endodontic landscape. Yet endodontists are heavily involved in treatment. Hence, confusing use of terminologies for anomalous dental developments appears in the endodontic literature.
Another attribute of the published research relating to these anomalies is multidisciplinary authorship. Sur- geons, paediatricians, orthodontists, endodontists, radi- ologists and periodontists often focus on the management of a specific clinical circumstance and its environs. The high prevalence of some anomalies in ethnic groups has generated national streams of investigation. For instance, in Turkey, the reported prevalence of anatomical varia- tions in endodontic morphology of maxillary lateral inci- sors ranges can be as high as 22% (3). Case reports frequently feature individuals of Turkish and Chinese descent. Moreover, access to dental services, which also affects research direction, varies internationally and regionally. These influences, together with associated lan- guage barriers to communication, have historically created isolated silos of ethnic-based inquiry. Accordingly, systematic reviews of anomalous dental development are often limited in scope and contain diverse opinions regarding optimal management and, to a lesser extent, terminology.
Hallett provided the first classification of ‘palatal invagi- nation of maxillary incisor teeth’ (4). Based on ‘degree of affection’ from ‘normal’, it embraces fourteen subdivi- sions of aberrancy. Hallett acknowledged an obvious problem: ‘deciding exactly what is a normal incisor, so wide were the variations discovered’. Three years later, Oehlers categorised DI according to apparent radio- graphic extension of the invagination (5). In simple terms, Group I are limited to the crown. Group II pen- etrate the crown and root. Group III penetrate the crown and root and communicate with the periodontal liga- ment. The pseudo-foramen, which Oehlers termed a burst, can be located either laterally or apically. Munir et al. have summarised alternative proposals and modifi-
cations to Oehlers’ classification (6). However, its simplic- ity and clinical relevance have ensured its widespread acceptance in contemporary dental literature.
A brief mention of closely aligned Australian literature is worthwhile. Variations in dental anatomy, including tooth fusions, have captured Australian dentists’ interest from the early 1950s (7). Barker reported dual roots in a central incisor in the Australian Dental Journal (8). Barker et al. published two of many manuscripts that related to dental anthropology, anatomy and aberrant tooth form, including DI (9,10). Mupparapu and Singer, Mupparapu et al., Lee et al., O’Reilly, Ozden et al. and Turker and Karaca published reports relating to anterior teeth in the same journal (11–16). Likewise, Collins, John, Low and Chan, McClelland, Pahl and George et al. are notable con- tributors to either the Australian Endodontic Journal or its precursor the Australian Endodontic Newsletter (1,17–21).
Several features are worthy of comment. First, many of the reports in the Australian literature were either based overseas or involved ethnic populations resident in Aus- tralia. Second, John, who enjoyed the diagnostic benefits of CBCT, is the only author who provided endodontic management that parallels this case. However, the affected tooth in John’s investigation lacked both a palatal evagination and a second root. Moreover, John did not specify the ethnic background of the patient. To the authors’ knowledge, this case report is the first to docu- ment DI and DE in an indigenous Australian. Hence, this report adds to a scant stream of literature.
Case report
Located in the Brisbane central business precinct, the Brisbane Dental Hospital provides both general and spe- cialist dental services to eligible patients. The patient, hereafter P, was a 15-year-old female with no relevant medical history. Prior dental records are sparse. A district dental officer ordered an orthopantomogram to assess periodontal bone height (Fig. 1). A radiologist coinciden- tally discovered and reported ‘The morphology of the 22 is unusual and this is consistent with a developmental anomaly. The appearance of the 22 is most suggestive of a dens invaginatus. There is a reasonably well defined lucency lying between the 22 and 23 roots and this has resulted in some separation of the roots of these teeth.
Lucency in the 22/23 region is most suggestive of longstanding inflammatory disease associated with a nonvital 22.’ The dental officer’s referral advised that the 22 was asymptomatic and requested ‘Treatment for non- vital (distal canal) 22 – dens invaginatus evident on PA.’
It also cautioned ‘22 responded positively to cold.’
At interview, a parent expressed two concerns. The first related to ‘the future of the tooth’. The second related to
inconvenience. Travel to Brisbane was onerous for family members. P is one of many siblings. The parent requested a minimum number of visits. There is no familial history regarding dental anomalies and no personal history of either dental or facial trauma. The deciduous dentition had allegedly developed, erupted and exfoliated without concern. Indigenous ancestry was acknowledged. P con- firmed that the 22 was asymptomatic.
The clinician used enhanced lighting (headlamp), mag- nification (loupes), transillumination and dental (straight and sickle) and periodontal probes to evaluate the coronal colours, contours and accessible root anatomy.
The clinically visible dentition showed neither crowding nor displacement. From the labial view, the appearance of the 22 crown was normal: the vertical-to-horizontal crown ratio was harmonious. There was no aesthetic concern with balance, proportion, surface texture, shape and size of the clinical crown.
The palatal enamel generally appeared of normal texture and colour. However, a 6 mm-long clinically non- cavitated (to sharp sickle probe), inverted, U-shaped, stained fissure was present on the palatal surface. The fissure was limited to the coronal enamel. A significant evagination without occlusal interference was present (Fig. 2a). The fissure captured a brownish discoloured block of enamel. Moreover, in comparison to the 12, the 22 had subtle (maximum 2 mm) broader labio-palatal contours. A cingulum was present but the normal 22 palatal concavity was largely obliterated by the base of a 3 mm-high evagination with an apparent invagination at its peak. No swelling of either the gingiva or mucosa was detected. Pigmentation in the attached gingiva was noted.
The results of the special tests, given the radiolucency on the 22, were confusing. The 21, 22 and 23 responded
positively to cold sensibility testing. The following tests were either negative or of little diagnostic value: controlled multidirectional percussion; firm palpation from labial and palatal; and mobility tests. Clinical analysis and study models identified no occlusal interferences. No para- functional habits were acknowledged. Multidirectional and sequential periodontal probing suggested no aberran- cies in the accessible root contour. No enamel-cemental fissuring either on or through the gingival margin, char- acteristic of a palatal groove defect, was detected.
A preoperative periapical radiograph was taken (Fig. 2b). The clinician used a commercial film holder and a modified paralleling technique in an attempt to standardise film angulation and to maximise accurate reproduction and visualisation of the apex. The radio- graph confirms aberrancies in root anatomy: one major but delicate and curved root, ostensibly with an intact lamina dura and endodontic patency; and a second trun- cated root with a delineated outline and a diffuse and open apex. A circumscribed, periapical radiolucency appears to be associated with the 22. The curved and spindly dominant root suggests atypical crown-root angulation and dimensions. A fragile root form is present.
The radiograph also suggests abnormal coronal histol- ogy and morphology. At the palatal opening of the invagi- nation, an ascending radio-opacity resembling that of enamel, appears to extend apically well above the level of the cemento-enamel margin. The radio-opacity, possibly surrounding either a canal or a fissure, seems fine but demarcated. The ill-defined radio-opacity across the crown suggests diffuse calcification of the dentine and minimal, if any, pulpal horns. This radiographic appear- ance is inconsistent with that of most 15-year-olds.
The radiographic peculiarity of the 22, in conjunction with the positive sensibility response, together with the absence of subgingival palatal grooving and the presence of localised coronal discolouration, a palatal aperture and two roots, suggested to the clinician that the dentino- pulpal complex in the main root was both autonomous and healthy. If these assessments were correct, non- surgical management of the invagination had to be con- sidered as a serious option. Given the paucity of reports regarding these phenomena and their non-surgical man- agement, these judgments confirm the clinician’s experi- ence and ability to think both critically and laterally.
Discussion
Diagnosis without CBCT, which option P’s parent refused, was vexatious. Many characteristics of an Oehlers type III DI are present: a normal labial appearance, a palatal enamel-lined invagination with root involvement that ends at an apical burst and an exaggerated lingual Figure 1 The orthopantomogram (OPG) accompanying the referral. Note
the presence of the radiolucency near the 22, the major root and the vertical radio-opacity ascending to an apparent apical burst in a truncated root.
cingulum. Additional supportive evidence for DI is a periapical radiolucency apparently associated with the truncated root, a positive sensibility test to cold and no overt pathological radiolucency on the main root. More- over, given the depth of the invagination into the root, it is reasonable to suggest that inner enamel epithelial pro- liferation within the enamel organ and into the dental papilla during the morpho-differentiation phase of tooth development was pronounced. An aggressive in-folding of inner enamel epithelial cells could not only extend the invagination through the dental papilla to lay the foundations for the accessory root but also create a simultaneous reverse-pressure out-folding to produce the evagination carrying an aperture. Furthermore, the interface between the internal enamel epithelium and the dental papilla would be the only boundary to carry a basement membrane, which is critical to both amelogenesis and dentinogenesis. If correct, these propo- sitions carried consequences for treatment planning. The enamel-lined aspect of the crown and truncated root did not contain a dentino-pulpal complex. The provisional diagnosis had to include Oehlers type III DI. Most impor- tantly, the dentino-pulpal complex in the main root did not require endodontic intervention.
A diagnosis of Oehlers type III DI assumes that the anomalous dental development is derived from a single tooth bud. Some evidence suggests that a supernumerary tooth bud may have been fused onto the 22 at an early stage of tooth development. The subtle (maximum 2 mm) broader labio-palatal contours and the presence of correct tooth count are two potential indicators of fusion (22). Location is another: the maxillary lateral incisor region is a common site for a supernumerary tooth.
Moreover, tooth fusion is ‘an ill-defined term’ and has been implicated in the aetiology of DI (6,14). Further- more, the presence of the second root is inconsistent with Oehlers’ portrayal of a type III DI, which unlike Hallett’s classification, does not provide for fused combinations
with a supernumerary element. These considerations were considered in a provisional diagnosis, which focused on DI and DE but did not rule out fusion.
A myriad of confounding factors affected prospects for a definitive diagnosis. The morphology of the maxillary lateral incisor is the most variable in the human denti- tion. For instance, Kottoor et al. reported ‘a maxillary lateral incisor with four root canals’ (23). Croll and Killian, Killian and Croll and Schuurs and van Loveren report shortfalls with assigning a single diagnostic term to a anomalously developed tooth (24–26). Bhargava et al.
and Killian and Croll suggest that a diagnosis of fusion, in the potential presence of supernumerary tooth, is difficult (25,27). Bockow et al. concurred but resolved the issues with CBCT (28). With regard to this 22, there are major objections to a fused supernumerary hypothesis: the presence of the tubular enamel-lined invagination and the apparent absence of adjoining enamel interfaces and associated dentino-pulpal complexes. Nonetheless, without CBCT, the potential presence of a fused super- numerary lingered in the clinician’s mind.
The presence of the evagination on the 22 is also intriguing. Oehlers, who used the term DI but not DE, recorded ‘exaggerated lingual cingula’ as an integral com- ponent of type III DI (5). A plethora of alternative terms, for instance DE, ‘accessory cusp’, ‘supernumerary cusp’
and ‘talon cusp’, emerge in later literature (29). The American Association of Endodontists’ glossary not only stipulates the presence of ‘enamel, dentin and pulpal tissue’ in DE but also ignores the aforementioned alter- native terms (2). Dankner et al. reviewed the literature regarding DE from 1970 to 1995 and stipulated that enamel, dentine and pulpal tissue have to be present in a DE (30). Seow stated that DE ‘usually contains pulp tissue which communicates with the main pulp chamber’ (31).
Gehlot et al. assert that a DE ‘may or may not contain pulpal tissue’ (32). Hence, the use of the term DE across the literature is inconsistent.
(a) (b) (c)
Figure 2 (a) Note the abovementioned features on the palatal of the 22. (b) The preoperative periapical radiograph confirms the presence of the radiolucency near the 22, the major root with an apparently intact lamina dura and a vertical radio-opacity with a seemingly patent and enamel-lined invagination ascending to an apical burst in a truncated root. (c) A post-access periapical radiograph showing an exploratory gutta-percha point.
One group of researchers has claimed prominence from this ambiguity in both definition and terminology. In the Australian Dental Journal, Mupparapu et al. stated that ‘the concurrence of DE and DI within the same tooth is a rarity and has never been reported’ (12). However, when compared with photographs displayed in Oehlers type III DI nearly 50 years previously, one has to question if Mupparapu et al.’s assertion is as distinctive as they claim (5). Agrawal et al., Anthonappa et al., Gehlot et al., Kiswani and Marya et al. have subsequently recorded the presence of DE and DI in the same tooth (32–36). Hence, if one accepts this trend in recent literature, this case report adds to a scant pool of evidence. Moreover, to the authors’ knowledge, the location of the invagination at the peak of the tubercle has rarely, if ever, been reported.
Regarding endodontic intervention, the clinician made further pivotal decisions, namely, the origins and diagno- sis of the problems were irrelevant to the scheme of treatment. Attention focused on problems relating to management. Did the positive sensibility result imply an autonomous and healthy dentino-pulpal complex in the main root? Did the enamel-lined DI and dentino-pulpal complex connect? Assuming the sole source of infection was the invagination throughout the truncated root, what were the consequences for obturation regarding the immature and open root apex, enamel-lined and thin apical walls and the absence of an apical stop? Was the osseous lesion either cystic or granulomatous? Did the size of the lesion warrant surgery? Should the surgical amputation and sealing of the extraneous root be seri- ously considered? Like the diagnosis, treatment presented challenges.
A primary approach involving apical surgery was ruled out for the following reasons. The enamel-lined invagi- nation possibly communicated with the dentino-pulpal complex. The potential for periodontal defects, for instance surgically induced fenestration and dehiscence, was another concern. The preservation of radicular integ- rity of the remaining spindly and curved root, especially in the event of either occlusal overload or prosthodontic intervention, was a further priority. A high lip line, intra- coronal breakdown products from necrotic pulpal tissue, apparently hyper-calcified coronal dentine, adolescent fixation with aesthetics, eventual coronal discolouration and potential effects of internally placed bleaching agents and later challenges for either a veneer or a post-retained crown: all featured in treatment planning. Hence, the resolution of endodontic issues was only one priority.
The preservation of coronal and radicular dentine and the potential for long-term aesthetic concerns were others.
Understanding the nature and extent of the anomaly is a prelude to both informed consent and competent endodontic intervention. Moreover, the doctrine of
autonomy, namely, the patient voluntarily decides treat- ment direction, is fundamental to informed consent. At this juncture, the parent for logistical reasons based on inconvenience to other family members, rejected a rec- ommendation for a CBCT image. Accordingly, P and the parent were advised that the clinical scenario was unusual; there was some doubt about the diagnosis;
endodontic intervention was recommended; conservative options would be attempted first; preliminary assess- ments of success for conservative modalities would require at least 6 months of observation; surgical inter- vention was a last resort; the 22 may be aesthetically compromised throughout teenage years; either a crown or a veneer in later life could be problematic; the 22 may have to be extracted either during or after treatment; and failure to treat 22 would probably lead to its eventual loss.
Based on this advice and associated discussions, treat- ment proceeded.
An experienced clinician can visualise both the canal morphology and optimal end-shape of an endodontic preparation. These skills are elusive and involve distance perception (length), spatial awareness (length, width and height), internal demarcation (insight as to outline of dentino-pulpal complex and DI) and, of course, angular discernment (differentiation between long axis of tooth and long axis of entry). The incisal edge of 22 provided a fixed, constant, reproducible reference point for endodontic measurements with minimal parallax error.
With a half round bur, access was made via the tip of the evagination and then followed an overt invagination.
Experience and forethought are obvious in the clini- cian’s determination of the axial inclination of the access cavity: down the long axis of the tooth, parallel and palatal to the expected location of the dentino-pulpal complex. As suspected from assessments of the PA radio- graph and to the clinician’s relief, the coronal access cavity and all visible (to a depth of approximately 5 mm) radicular preparation, appeared to be surrounded by enamel. Scouting of the invagination with a gutta-percha point and an exploratory endodontic file suggested that the enamel extended almost to the apex of the second root (Fig. 2c). There was exudate but no haemorrhage. A smooth, continuous, parallel preparation provided both centrality and a glide path that facilitated straight-line access into the apical aspect of the invagination. There was a paradox. Throughout all the visits for endodontic treatment, the 22 responded to cold.
Conventional biomechanical shaping and cleaning were tailored to the circumstance. An apex locator gave inconsistent readings. Sustained tactile exploration with larger hand files again implied that most, if not all, of the radicular aspect of the preparation was lined with enamel. The clinician noted that caution was warranted
because the walls of the preparation were so hard that files could inadvertently bind. This observation was a dual-edged sword. The shortcomings were token use of nickel titanium rotary instrumentation and minimal mechanical preparation. The benefit was that, in all prob- ability, the enamel-lined invagination formed a discrete entity. Connection to the dentino-pulpal complex was unlikely. Irrigation involved 4% sodium hypochlorite (NaOCl). A calcium hydroxide dressing was sealed in place using a temporary restorative material covered with self-cure glass ionomer cement.
After 2 months, no symptoms had developed. The 22 continued to respond to cold. Treatment of the endo- dontic preparation then involved irrigation with NaOCl, followed at the end of biomechanical preparation by ethylenediaminetetraacetic acid and a final rinse of NaOCl.
White mineral trioxide aggregate was sealed into the radicular aspect and overlaid with a self-cured temporary restorative material and a chemical-set glass ionomer res- toration. A 6 month review radiograph (Fig. 3a) and pho- tograph (Fig. 3b) confirm osseous healing and minimal coronal discolouration. These observations lend further support to evidence suggesting the presence of an autono- mous pulpal system and DI in the 22. P did not present for a 12 month review radiograph.
Conclusion
This case report demonstrates the importance of many themes in endodontic practice. The diagnosis confirms the roles of history taking, visual and tactile examinations, sensibility testing, transillumination and radiology as essential preambles to intervention. Of course, interpret- ing the findings, for instance, accurate assessment of dental anatomy, authoritative diagnosis of pulpal mor- phology and status and careful planning of intervention, require knowledge, skill and experience. The last was obvious not only in assessments of the locations and the morphologies of the pulpal system and the enamel-
lined invagination but also in executing the site, outline, angulation and depth of access. The elusive skills of angular discernment, distance perception, internal demar- cation and spatial awareness underpinned appropriate access to the coronal and radicular dimensions of the invagination. While there could be debate concerning the nature and classification of the anomalies, the clinician understood the clinical implications and fashioned con- ventional chemo-mechanical principles to the circum- stance. The definitive diagnosis, probably DE and DI, is irrelevant to treatment outcome.
References
1. John V. Non-surgical management of infected type III dens invaginatus with vital surrounding pulp using con- temporary endodontic techniques. Aust Endod J 2008;
34: 4–11.
2. American Association of Endodontists. Glossary of endodontic terms. 8th ed. Chicago, IL: American Asso- ciation of Endodontists; 2012.
3. Cantatore G, Berutti E, Castellucci A. Missed anatomy:
frequency and clinical impact. Endod Top 2009; 15: 3–31.
4. Hallett GEM. The incidence, nature and clinical signifi- cance of palatal invagination in the maxillary incisor teeth. Proc R Soc Med 1953; 46: 491–9.
5. Oehlers FAC. Dens invaginatus (dilated composite odontome) I. Variations of the invagination process and associated anterior crown forms. Oral Surg Oral Med Oral Pathol 1957; 10: 1204–18.
6. Munir B, Tirmazi SM, Majeed HA, Khan AM, Iqbalbangash N. Dens invaginatus: aetiology, classifica- tion, prevalence, diagnosis and treatment considerations.
Pak Oral Dent J 2011; 31: 192–3.
7. Gabriel AC. Human teeth of unusual form. Dent J Aust 1953; 25: 43–9.
8. Barker BCW. A two rooted permanent maxillary median incisor. Aust Dent J 1964; 9: 501.
9. Barker BCW. Dental anthropology. Some variations and anomalies in human tooth form. Aust Dent J 1973; 18:
132–40.
10. Barker BCW, Lockett BC. Dens invaginatus. Case report.
Aust Dent J 1978; 23: 156–8.
11. Mupparapu M, Singer SR. A rare presentation of dens invaginatus in a mandibular lateral incisor occurring concurrently with bilateral maxillary dens invaginatus:
case report and review of literature. Aust Dent J 2004;
49: 90–3.
12. Mupparapu M, Singer SR, Goodchild JH. Dens evaginatus and dens invaginatus in a maxillary lateral incisor: report of a rare occurrence and review of litera- ture. Aust Dent J 2004; 49: 201–3.
13. Lee AMP, Bedi R, O’Donnell D. Bilateral double dens invaginatus of maxillary incisors in a young Chinese girl.
Aust Dent J 1988; 33: 310–2.
(a) (b)
Figure 3 (a) Note the osseous healing. (b) The buccal view with minimal, if any, discolouration.
14. O’Reilly PMR. Structural and radiographic evaluation of four cases of tooth fusion. Aust Dent J 1990; 35:
226–9.
15. Ozden B, Gunduz K, Ozer S, Otan Ozden F. The multi- disciplinary management of a fused maxillary central incisor with a talon cusp. Aust Dent J 2012; 57:
98–102.
16. Turker M, Karaca I. Early pulpal involvement in an unusual case of dens in dente. Case report. Aust Dent J 1993; 38: 439–41.
17. Collins IJ. Maxillary lateral incisor with two roots. Aust Endod J 2001; 27: 37–8.
18. Low D, Chan AWK. Unusual maxillary lateral incisors:
case reports. Aust Endod J 2004; 30: 15–9.
19. McClelland T. Dens invaginatus; dens evaginatus; talon cusp? Genghis Khan’s trilogy of dental abnormalities?
Aust Endod News 1997; 23: 17–20.
20. Pahl J. Endodontic/periodontic management of aberrant morphology of a maxillary central incisor. Aust Endod News 1994; 20: 28–30.
21. George R, Moule AJ, Walsh LJ. A rare case of dens invaginatus in a mandibular canine. Aust Endod J 2010;
36: 83–6.
22. Mader CL. Fusion of teeth. J Am Dent Assoc 1979; 98:
62–4.
23. Kottoor K, Murugesan R, Albuquerque DV. A maxillary lateral incisor with four root canals. Int Endod J 2012;
45: 393–7.
24. Croll TP, Killian CM. Double Dental Twinning in two Chil- dren. Inside Dentistry 2012; 8: np. [PDF on Internet].
Newtown PA: AEGIS Publications, published May 2012, [Cited 26 November 2012.] Available from URL: http://
www.dentalaegis.com/id/2012/05/double-dental- twinning-in-two-children
25. Killian CM, Croll TP. Dental twinning anomalies: the nomenclature enigma. Quintessence Int 1990; 21: 571–6.
26. Schuurs AH, van Loveren S. Double teeth: review of the literature. J Dent Child 2000; 67: 313–25.
27. Bhargava M, Chaudhary D, Aggarwal S. Fusion present- ing as gemination – a rare case report. Oral Maxillofac Pathol J 2012; 3: 211–4.
28. Bockow R, Evans M, Chung C. Diagnosis of anomalous teeth with cone-beam computed tomography. J Clin Orthod 2012; XLVI: 157–8.
29. Oredugba FA. Mandibular facial talon cusp: case report.
BMC Oral Health 2005; 5: 9.
30. Danker E, Harari D, Rotsein I. Dens evaginatus of ante- rior teeth literature review and radiographic survey of 15 000 teeth. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998; 81: 472–5.
31. Seow WK. Diagnosis and management of unusual dental abscesses in children. Aust Dent J 2003; 48: 156–8.
32. Gehlot PM, Manjunath V, Manjunath MK. Concurrent occurrence of developmental anomalies – dens evaginatus and dens invaginatus in maxillary lateral incisor: report of two cases. J Orofacial Res 2012; 2:
178–81.
33. Agrawal J, Shenai PK, Chatra LK, Prabhu R. Concurrent occurrence of dens evaginatus and dens invaginatus in maxillary incisors: a case report and review. Oral Radiol 2011; 27: 121–4.
34. Anthonappa RP, Yiu CKY, King NM. A novel combina- tion of dens evaginatus and dens invaginatus in a single tooth – review of the literature and a case report. J Clin Pediatr Dent 2008; 32: 239–42.
35. Kiswani K. Concomitant dens evaginatus & dens invaginatus in a maxillary lateral incisor: a case report.
Oral Maxillofac Pathol J 2013; 4: 399–402.
36. Marya CM, Parashar V, Grover S, Dahiya V. A rare case of dens evaginatus and dens invaginatus in the same tooth, with a review of treatment options. Gen Dent 2011; 59: 182–4.
