Dens invaginatus is a rare developmental anomaly of the teeth that is caused by the infolding of enamel organs or the penetration of their proliferations into dental papillae before calcification has occurred. The presence of double dens invaginatus is extremely rare. This paper describes the use of cone beam computed tomography in the evaluation of a maxillary lateral incisor with double dens invaginatus and periapical periodontitis. The tooth was treated through microscopic root canal therapy. The tooth was free of clinical symptoms, and the periradicular lesion narrowed during the follow-up period of 1 year.
Humans ; Dental Pulp Cavity/abnormalities* ; Dens in Dente/pathology* ; Incisor/pathology* ; Root Canal Therapy ; Periapical Periodontitis/pathology*

A three-year-old female beaver (Castor canadensis) was referred to the Veterinary Teaching Hospital of Chungbuk National University. It had been raised in the Cheong-ju zoo and had a history of malocclusion caused by improper feeding. General anesthesia was induced, and preoperative intraoral dental radiographs of the rostal maxillary and mandibular dentition were taken and lateral and ventrodorsal extraoral radiographs of the cheek teeth were also taken. The radiographs were negative for apical pathology and revealed a normal appearance of the cheek teeth. The lesion was likely to be related to the excessive length of the maxillary and mandibular incisors. Odontoplasty was performed to reduce overgrowth of the crowns of the incisors. Sequential transverse sections were removed until the crown was reduced by approximately its original length. The pulp chamber was not approached during the operation, as confirmed by postoperative intraoral radiographic evaluation of the incisors. Recovery from anesthesia was uneventful and the beaver returned to normal masticatory activities immediately after the operation.
Animals ; Animals, Zoo ; Female ; Incisor/pathology/*surgery ; Malocclusion/pathology/surgery/*veterinary ; Rodentia/*surgery

OBJECTIVETo study the TC index location on a reform LONGA' s animal model of regional experimental cerebral ischemia and reperfusion.

METHODSA total of 300 SD male rats were randomly divided into the pre-test group (n = 30), the original method group (n = 120, Longa' s method) and the reform method group [ n = 150, TC index location is defined by the length of rat incisor teeth root (T point) to the common carotid artery bifurcation (C point) ,the blood flow of a unilateral middle cerebral artery in the rats was reversibly blocked by the TC index location). The morphologic changes and the successful rate of the two methods to establish the rat model were compared.

RESULTSThe successful rate of TC index location modified model method was superior to that of original LONGA' s method,with significant difference in linear correlation analysis.

CONCLUSIONThe reform LONGA' s animal model of regional experimental cerebral ischemia and reperfusion by the TC index location is a good method, and is worth applying in experimental study.

Animals ; Brain Ischemia ; pathology ; Carotid Arteries ; pathology ; Disease Models, Animal ; Incisor ; pathology ; Male ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; pathology

OBJECTIVETo investigate the dentoalveolar characteristics in skeletal class I patients with excessive overjet.

METHODSTen cephalometric measurements of 60 skeletal class I patients with excessive overjet were analyzed.

RESULTSCompared with patients with normal overjet, 1-SN, 1-NA and MxAAH were significantly increased in excessive overjet group I (overjet: 3 - 5 mm) and 1-SN, 1-NA and MxAAH were significantly increased in excessive overjet group II (overjet: 5 - 7 mm).

CONCLUSIONSThe protrusion and tipping of maxillary incisor, and absence of compensatory proclination of mandibular incisor may be the factors, caused skeletal class I excessive overjet. Increased height of anterior maxillary anterior alveolar process was the compensatory change in skeletal class I patients with excessive overjet.

Adolescent ; Alveolar Process ; diagnostic imaging ; pathology ; Cephalometry ; Child ; Female ; Humans ; Incisor ; diagnostic imaging ; pathology ; Male ; Malocclusion, Angle Class I ; diagnostic imaging ; pathology ; Radiography

Basaloid-squamous cell carcinoma, a biologically high-grade variant of squamous cell carcinoma, is predominantly located at upper aerodigestive tract but it is extremely rare in the esophagus. Recently we experienced a case of basaloid-squamous cell carcinoma of esophagus. A 64 year-old man was referred to our hospital because of mucosal nodularity at 35 cm apart from the incisor in endoscopic examination. Result of Biopsy was squamous cell carcinoma. Left transthoracic esophagectomy was performed. Histologically, the lesion of tumor was basaloid- squamous cell carcinoma and no lymph node metastasis was found.
Biopsy ; Carcinoma, Squamous Cell ; Esophageal Neoplasms ; Esophagectomy ; Esophagus* ; Humans ; Incisor ; Lymph Nodes ; Middle Aged ; Neoplasm Metastasis ; Pathology

OBJECTIVETo study the alveolar bone surrounding situation and the length of the root of the maxillary labial inverted impacted incisor in mixed dentition after orthodontic treatment.

METHODSFourteen cases with maxillary labial inverted impacted incisor in mixed dentition were collected. Modified Nance arch and conventional appliance were used. Cone-bean CT (CBCT) was taken after the treatment. Simplant13.0 three-dimensional reconstruction and multi-planer reconstruction (MPR) method were used to observe the labial and lingual alveolar bone crest morphology, besides, the labial and lingual length from the alveolar bone crest to cemento-enamel junction (CEJ) of the impacted incisor and the homonym tooth after treatment, along with their root length and their labial and lingual length ratio of the root surrounded by the alveolar bone to the total root length were measured. The idependent samples t-test were used to analyze the variable differences.

RESULTSThe labial and lingual alveolar bone of fourteen cases crest of the diseased tooth after treatment presented general symmetry U shape from qualitative observation through the three-dimensional reconstruction. The labial and the lingual length of the diseased incisor from alveolar bone crest to CEJ [(2.47 ± 1.35) and (1.47 ± 0.84) mm] was significant increased than those of the homonym incisor [(1.03 ± 0.35) and (0.90 ± 0.37) mm] (P < 0.05); the length of the diseased incisor's post-treatment root [(9.82 ± 2.82) mm] was no statistically significant decreased than that of the homonym incisor root [(10.28 ± 1.38) mm, P = 0.59]; the labial and the lingual length ratio of the impacted tooth's root surrounded by the alveolar bone to the total root length [(72.83 ± 17.16)% and (85.32 ± 5.98)%] was statistically significant decrease than those of homonym teeth[(89.66 ± 3.98)% and (90.84 ± 4.61)%] (P < 0.05).

CONCLUSIONSThe diseased tooth's root had gotten enough length after the treatment. The labial and lingual alveolar bone of the maxillary labial inverted impacted incisor in mixed dentition can't offer sufficient adaptive hyperplasia after treatment, of which labial alveolar bone is more apparent, prompting careful protection when they were used.

Alveolar Process ; diagnostic imaging ; pathology ; Child ; Cone-Beam Computed Tomography ; Dentition, Mixed ; Female ; Follow-Up Studies ; Humans ; Incisor ; diagnostic imaging ; pathology ; surgery ; Male ; Maxilla ; diagnostic imaging ; pathology ; surgery ; Orthodontic Extrusion ; Tooth Root ; diagnostic imaging ; pathology ; Tooth, Impacted ; diagnostic imaging ; surgery

AIMCluster analysis was conducted on data from 5,169 United States (U.S.) Arizona children, age's 5-59-months with the goal of delineating patterns of caries in the primary dentition of pre-school children without a priori pattern definitions.

METHODOLOGYCluster analyses were conducted using all data for children ages 0-4 years in aggregate: (1) for all subjects, and (2) for subjects without crowned restored teeth. Each of these two sets of analyses consisted of 8 differently specified cluster analyses as a validation procedure.

RESULTSThe caries patterns identified from the clustering analysis are: (1) smooth surfaces (other than the maxillary incisor), (2) maxillary incisor, (3) occlusal surfaces of first molars, and (4) pit and fissure surfaces of second molars.

CONCLUSIONThe cluster analysis findings were consistent with results produced by multidimensional scaling. These cross-validated patterns may represent resulting disease conditions from different risks or the timing of various risk factor exposures. As such, the patterns may be useful case definitions for caries risk factor investigations in children under 60 months of age.

Arizona ; epidemiology ; Caregivers ; education ; Child, Preschool ; Cluster Analysis ; Cohort Studies ; Dental Caries ; epidemiology ; Dental Enamel ; pathology ; Dental Fissures ; epidemiology ; Educational Status ; Ethnic Groups ; statistics & numerical data ; Female ; Humans ; Incisor ; pathology ; Infant ; Male ; Mandible ; Maxilla ; Molar ; pathology ; Tooth, Deciduous ; pathology

OBJECTIVETo observe the effect of overdose fluoride on the proliferation of rat's incisor ameloblast.

METHODS20 Wistar rats were divided randomly into 2 groups: Group I (Control); Group II 50 mg/L F(-) were given. After 8 weeks treatment, the AgNORs stain and TUNEL technique were applied to analyze the effect of fluoride on the proliferation and apoptosis of ameloblasts.

RESULTSThe imagination analysis results showed that proliferation of pre-secretion ameloblasts were inhibited in group II as compared with the control group (P < 0.001). There was significant increase of apoptosis with the trend of migration toward secretion stage.

CONCLUSIONThe mechanism of fluorosis mottled enamel may be the effect of overdose fluoride with inhibits proliferation and induces apoptosis of ameloblasts resulting in dysfunction of secretion or absorption of enamel matrix proteins.

Ameloblasts ; drug effects ; pathology ; Animals ; Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Dental Enamel ; pathology ; Female ; Fluorides ; adverse effects ; Fluorosis, Dental ; pathology ; Incisor ; Male ; Random Allocation ; Rats ; Rats, Wistar

AIMTo determine cephalometrically the mechanism of the treatment effects of non-extraction and multiloop edgewise archwire (MEAW) technique on postpeak Class II Division 1 patients.

METHODOLOGYIn this retrospective study, 16 postpeak Class II Division 1 patients successfully corrected using a non-extraction and MEAW technique were cephalometrically evaluated and compared with 16 matched control subjects treated using an extraction technique. Using CorelDRAW software, standardized digital cephalograms pre- and post-active treatments were traced and a reference grid was set up. The superimpositions were based on the cranial base, the mandibular and the maxilla regions,and skeletal and dental changes were measured. Changes following treatment were evaluated using the paired-sample t-test. Student's t-test for unpaired samples was used to assess the differences in changes between the MEAW and the extraction control groups.

RESULTSThe correction of the molar relationships comprised 54% skeletal change (mainly the advancement of the mandible) and 46% dental change. Correction of the anterior teeth relationships comprised 30% skeletal change and 70% dental change.

CONCLUSIONThe MEAW technique can produce the desired vertical and sagittal movement of the tooth segment and then effectively stimulate mandibular advancement by utilizing the residual growth potential of the condyle.

Adolescent ; Case-Control Studies ; Cephalometry ; Female ; Follow-Up Studies ; Humans ; Image Processing, Computer-Assisted ; Incisor ; pathology ; Male ; Malocclusion, Angle Class II ; pathology ; therapy ; Mandible ; growth & development ; pathology ; Mandibular Condyle ; growth & development ; pathology ; Maxilla ; pathology ; Molar ; pathology ; Orthodontic Appliance Design ; Orthodontic Retainers ; Orthodontic Wires ; Retrognathia ; pathology ; therapy ; Retrospective Studies ; Serial Extraction ; Skull Base ; pathology ; Software ; Tooth Movement Techniques ; instrumentation ; methods ; Treatment Outcome ; Young Adult

AIMTo investigate the relationship between the positioning of the lower central incisor and physical morphology of the surrounding alveolar bone.

METHODOLOGYThirty-eight patients (18 males, 20 females), with mean age of 13.4 years, were included in this study. As part of orthodontic treatment planning the patients were required to take dental Cone-beam CT (CBCT) covering the region of lower incisors, the surrounding alveolar bone and the mandibular symphysis. The cephalometric parameters were designed and measured to indicate the inclination of lower central incisor and physical morphology of the adjacent alveolar bone. Computer-aided descriptive statistical analysis was performed using SPSS 15.0 software package for Windows. A correlation analysis and a linear regression analysis between the incisor inclination and the alveolar bone morphology were performed.

RESULTSSignificant positive correlations were found between the lower central incisor inclination and the morphological contour of the alveolar bone (P < 0.05). The lower central incisor root apex was closer to the lingual alveolar crest when it was buccally inclined.

CONCLUSIONThe morphology of the alveolar bone may be affected by incisal inclination.

Adolescent ; Alveolar Process ; diagnostic imaging ; pathology ; Cephalometry ; methods ; Chin ; diagnostic imaging ; pathology ; Cone-Beam Computed Tomography ; methods ; Female ; Humans ; Incisor ; diagnostic imaging ; pathology ; Male ; Mandible ; diagnostic imaging ; pathology ; Numerical Analysis, Computer-Assisted ; Patient Care Planning ; Software ; Tooth Apex ; diagnostic imaging ; pathology