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Concept: Maxillary lateral incisor


The aim of the study was to test the hypothesis that the gene defect causing congenital absence of maxillary lateral incisors also causes narrowing of the dentition. A total of 81 patients with one or two congenitally missing lateral incisors were retrieved; 52 (64.2 per cent) patients presented bilateral agenesis, whereas 29 (35.8 per cent) had unilateral agenesis. The control group consisted of 90 consecutively treated patients. The largest mesiodistal crown dimension for all teeth, except for the maxillary second and third molars, was measured on plaster casts using a digital caliper to the nearest 10th of a millimetre. Statistical testing was performed using the analysis of variance model (P < 0.05) to test for differences in the mesiodistal dimension between the sample and the control group. Significance has been assessed using a P-value threshold level of 5 per cent. Agenesis of maxillary lateral incisors was found to be a significant predictor of tooth size. Patients who were missing maxillary lateral incisors had smaller teeth compared to control subjects, except for the maxillary right and left first molars. This finding was true for both unilateral and bilateral lateral incisor agenesis. Interaction between maxillary lateral incisor agenesis and gender was not significant. Patients with congenitally missing lateral incisors have narrower teeth than patients without any dental anomalies, except for maxillary first molars. A higher prevalence of microdontic contralateral incisors was found in patients with unilateral agenesis with respect to the control group.

Concepts: Teeth, Analysis of variance, Molar, Incisor, Maxillary central incisor, Canine tooth, Maxillary lateral incisor, Mandibular lateral incisor


Skulls (n = 1,205) of southern sea otters were examined macroscopically according to defined criteria. The museum specimens, acquired from strandings, varied in age from juvenile to adult, with an equal sex distribution. The results from all young adult and adult specimens were pooled according to tooth type. Ninety-two percent of teeth were available for examination, with 6.5% artifactually absent, 0.6% deemed absent due to acquired tooth loss and 0.03% deemed congenitally absent. All teeth were normal in morphology, except for three pairs of fused teeth, including two instances of fused maxillary first incisor teeth. Supernumerary teeth were associated with 97 normal teeth (most commonly maxillary canine teeth) in 68 specimens. At least one persistent deciduous tooth was present in six skulls, two of which were from adults. The majority (94.6%) of alveoli, either with or without teeth, were not associated with bony changes consistent with periodontitis; however, the majority (74.4%) of specimens did have at least one tooth associated with mild periodontitis. The mesial root of the mandibular third premolar tooth was the most common location at which periodontal hard tissue lesions were observed (56.6%). Ten sea otters had lesions consistent with focal enamel hypoplasia. Approximately half of the teeth (52.0%) were abraded; almost all adult specimens (98.1%) contained at least one abraded tooth, while fewer young adults were affected (76.4%). Tooth fractures were uncommon, affecting 1,343 teeth (4.5%). Periapical lesions were associated with 409 teeth (1.3%) in a total of 176 specimens, and these would likely have caused considerable morbidity while the animals were alive.

Concepts: Teeth, Tooth development, Incisor, Canine tooth, Maxillary lateral incisor, Premolar, Sea otter, Deciduous teeth


External cervical resorption is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. This case report demonstrates an external cervical resorption in a maxillary central incisor of a 24-year-old male patient. After surgical intervention and root canal treatment, the resorption was subsequently sealed with mineral trioxide aggregate. The 18 months follow-up demonstrates no pathological changes on clinical and radiographic examination. This case report presents a treatment strategy that might improve the healing outcomes for patients with external cervical resorption.

Concepts: Hospital, Mammal, Teeth, Endodontic therapy, Endodontics, Incisor, Maxillary central incisor, Maxillary lateral incisor


- Primary tooth impaction is a rare phenomenon when compared to permanent teeth impaction. The purpose of this report is to present a 5-year-old Chinese girl who exhibited impaction of tooth 51, its unusual consequence on the permanent successor tooth and its comprehensive management. Her parents revealed that at 6 months of age, the patient had fallen from her bed and struck her face on the floor; however, there were no teeth present in the oral cavity. The intraoral examinations identified a bony-like projection on the buccal aspect of the alveolus in the 51 region. Radiographic examination revealed that tooth 51 exhibited an unfavourable orientation, with the crown directed towards the palate. Therefore, the impacted tooth 51 was surgically removed, and two years later tooth 11 erupted into the oral cavity with an indentation on its incisal aspect, which resembled the crown of the primary teeth, thus giving the appearance of a tooth within a tooth or ‘dens in dente’. Subsequently, enameloplasty and composite resin build-up was performed on tooth 11 for aesthetic reasons. It is very unusual to have the clinical crowns of both primary and permanent teeth in such close proximity within the alveolar bone, and the present case is a good example to emphasize that trauma to the primary teeth is of considerable importance due to the close proximity of the primary teeth to permanent tooth germs.

Concepts: Teeth, Incisor, Maxillary central incisor, Canine tooth, Maxillary lateral incisor, Deciduous teeth, Permanent teeth


To analyze and compare external apical root resorption (EARR) of maxillary incisors treated by intrusion arch or continuous archwire mechanics.

Concepts: Maxillary central incisor, Maxillary lateral incisor



Several factors, including anomalies of shape, color, or size, or positioning of the teeth, may interfere with smile esthetics. A 26-year-old woman was dissatisfied with the esthetics of her maxillary lateral incisors, which had defective composite resin restorations with alterations of color and shape. The aim of this article is to present a step-by-step description of the technique used to fabricate esthetic restorations for the conoid maxillary lateral incisors with a minimum of dental preparation. The successful outcome demonstrates the importance of correct planning for successful restorations.

Concepts: Factor analysis, Composite material, Teeth, The Technique, Maxillary lateral incisor, Aesthetics, Dental composite


Orthodontic treatment of a complex case that involves retained deciduous mandibular second molars with missing permanent successors is challenging. Usually, congenitally missing teeth are manifested with other dental anomalies that further complicate orthodontic treatment, such as retained deciduous teeth, impactions, transpositions and peg-shaped lateral incisors. Even though the long term prognosis of the retained deciduous tooth is not fully predictable, if the teeth are in good condition, the patient and clinician may incline towards a decision to preserve the deciduous teeth as long as possible. This case report demonstrates that deciduous teeth, in this case the mandibular second molars and maxillary canine, can be incorporated into final occlusion with clinically stable long-term results.

Concepts: Teeth, Canine tooth, Maxillary lateral incisor, Premolar, Deciduous teeth


The aim of this study is to determine whether variation in size, morphology, and color of a unilateral substituted maxillary canine has influence on the dentogingival attractiveness perceived by dental professionals and laypeople.

Concepts: Teeth, Incisor, Maxillary central incisor, Canine tooth, Maxillary lateral incisor, Maxillary canine


The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs), modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction.

Concepts: Incisor, Maxillary central incisor, Maxillary lateral incisor