A protostylid is a relatively rare dental developmental aberration characterized as an extra cusp located on the mesial half of the buccal surface of the molars. A protostylid is rarely to be reported due to its low rate of occurrence. This case report describes a patient referred for endodontic treatment due to the presence of a protostylid on the buccal surface of the maxillary first molar that induced apical periodontitis.
A 53-year-old female reported a 3-month history of pain of chewing with her upper left posterior teeth over 3 months. In the clinical examination, an abraded anomalous cusp-like structure was found on the buccal surface of tooth 26, Cone beam computed tomography (CBCT) revealed a supernumerary cusp with an intact root canal inside, which was fused with the mesiobuccal (MB) root canal in the middle of the root. In addition, extensive periapical radiolucency was observed around tooth 26. The tooth was diagnosed as apical periodontitis, and endodontic treatment was performed. The initial lesion in tooth 26 gradually healed over 1 year of observation.
To our knowledge, this case is the first to describe the endodontic management of a maxillary first molar with a protostylid and advances our understanding of supernumerary cusps. This case provides a reference for the treatment of protostylid.

Teeth arise by complex and progressive interactions between the ectoderm, oral epithelium and underlying mesenchyme. However, it may show variations and changes in morphological structure. A 6-year-old female child patient came for the treatment of her carious tooth. Intraoral examination revealed supernumerary cusp on occlusal surface of the maxillary right second primary molar. Incidence of supernumerary cusp is a rare condition formed by abnormal proliferation and folding of inner enamel epithelium during morphodifferentiation stage of the tooth development. Conservative cavity preparation and restorative treatment protocol were carried out to treat this case. Early diagnosis, management and timely recall of these rare anomalies will help to avoid potential complications, resulting from faster carious progression in these teeth due to the presence of many fissures and early pulpal extensions into the cuspal area.

Teeth with dens evaginatus (DE) are more commonly observed in Western countries than previously. This is due to the increase in populations of patients of Asian origin, in whom DE is more common than in people of European origin. The interest in DE has also increased with the introduction of a procedure called regenerative endodontics.
A narrative review of treatment options for teeth with DE is presented, based on pulpal conditions and maturity of the teeth.
Early recognition of teeth with DE allows for treatment choices that generally lead to good outcomes and can aid in preserving developing teeth in young patients.

Developmental malformations of the teeth might result in alterations of their size, shape, and structure. An accessory cusp is a developmental alteration to the shape of the teeth and is more commonly found in anterior teeth, and its occurrence in permanent molars is quite rare. Accessory cusps occurring in permanent mandibular molars are termed as protostylids. Although they do not pose any significant problem with respect to the function and occlusion, it is of tremendous importance in forensic odontology. This case report presents a rare finding of protostylid on the permanent mandibular molar, and its clinical implications are illustrated.

OBJECTIVE: Based on a case of supernumerary cusp on the bucca of left maxillary second molar diagnosed by cone beam computed tomography (CBCT), its genesis, diagnosis and antidiastole are to be analysed. The clinic implication of CBCT is correspondingly discussed.
METHODS: The supernumerary cusp was diagnosed by oral general examination, intra-oral radiograph and CBCT. The features of supernumerary cusp, fused tooth, geminated tooth and concrescence tooth, especially differentiate points among them were discussed.
RESULTS: The case of supernumerary cusp on the bucca of left maxillary second molar was diagnosed definitely by the combined application of oral general examination, periapical radiograph and CBCT.
CONCLUSIONS: Supernumerary cusp on the bucca of left maxillary second molar is a rare phenomenon, which is difficult to be differentiated from other tooth deformities. CBCT can improve accuracy of diagnosis.

Anatomic variations may be observed in the crown or in the roots of maxillary molars. In rare instances, crown and root morphology, both show variations. Occurrence of paramolar cusp on the occlusal surface as central cusp or on the buccal surface as parastyle has been frequently reported in maxillary molars. However, presence of paramolar cusp on the palatal surface has not been reported. \'Formation supradentalis\' is a condition in which supernumerary cusp is associated with a supernumerary root in a molar. The occurrence of such concomitant corono-radicular morphology is multifactorial, that is primary polygenic with secondary environmental influences. This case reports the diagnosis and endodontic management of Formation-supradentalis that had six cusps and four roots in the maxillary first molar. The tooth exhibited a prominent paramolar palatal cusp and cusp of Carabelli along with a supernumerary palatal root. To the best of author\'s knowledge, this is the first documentation of endodontic management of Formation supradentalis.