OBJECTIVE: To analyze the factors related to spontaneous re-eruption after intruded injury in permanent anterior teeth in children and adolescents. METHODS: Clinical data from 5- to 17-year-old patients who sustained intrusive luxation of permanent anterior teeth and treated in the Department of Pedia-tric Dentistry of Peking University School and Hospital of Stomatology from June 2015 to August 2024 were reviewed. Information of age, gender, degree of intrusion, direction of intrusion, tooth development, concomitant injuries, luxation and post-osteoclastic eruption of the adjacent teeth were recorded. The patients were divided into two groups based on whether they showed spontaneous re-eruption during advised observation after intrusion. Univariate and multifactor analysis were performed using Logistic regression. RESULTS: Data from 170 teeth in 139 patients whose age ranging from 5.3-16.3 years [mean age (9.0± 2.1) years] were examined. A gender disparity was observed among the patients, with 84 being male and 55 being female. Among the 170 teeth, 112 were categorized as successfully spontaneous re-eruption during advised observation after intrusion, while 58 were not. In terms of the degree of intrusion, 45 teeth (26.47%) had intrusion less than 3 mm, 102 teeth (60.00%) experienced intrusion between 3-7 mm, and 23 teeth (13.53%) were faced with intrusion exceeding 7 mm. As for the direction of intrusion, 117 teeth (68.82%) were straight intrusion while mesial-distal and buccal-lingual intrusion respectively accounting for 17 (10.00%) and 23 (13.53%). Multivariate Logistic regression analysis showed that mesial-distal intrusion (OR=0.167, 95%CI: 0.031-0.9048, P=0.038), intrusion of >7 mm (OR=0.065, 95%CI: 0.014-0.299, P < 0.001) and luxation of adjacent teeth (OR=0.369, 95%CI: 0.144-0.944, P=0.037) were independent risk factors for spontaneous re-eruption of traumatically intruded permanent anterior teeth in children and adolescents during advised observation after intrusion, while intrusion of < 3 mm (OR=9.860, 95%CI: 2.430-40.009, P=0.001) and post-osteoclastic eruption of adjacent teeth (OR=4.712, 95%CI: 1.528-14.531, P=0.007) were independent protective factors. The possibility of spontaneous re-eruption in permanent anterior teeth during advised observation after intrusion was decreased by 61.1% with the increase of root development using Cvek' s classification (OR=0.611, 95%CI: 0.408-0.914, P=0.017). Age (OR=1.077, 95%CI: 0.763-1.521, P=0.673) and laceration of gingival (OR=0.865, 95%CI: 0.290-2.578, P=0.794) didn't significantly affect the spontaneous re-eruption during advised observation after intrusion. CONCLUSION In this study, mesial-distal intrusion, intrusion of >7 mm and luxation of adjacent teeth were independent risk factors for spontaneous re-eruption of traumatically intruded permanent anterior teeth in children and adolescents during advised observation, while intrusion of < 3 mm and post-osteoclastic eruption of adjacent teeth were served as independent protective factors.
Humans ; Adolescent ; Child ; Female ; Male ; Tooth Eruption/physiology* ; Child, Preschool ; Tooth Avulsion/therapy* ; Dentition, Permanent ; Incisor/injuries* ; Remission, Spontaneous

OBJECTIVES: This study aimed to investigate the clinical characteristics of deciduous fused teeth and their inherited permanent-tooth performance type by using panoramic radiographs. METHODS: A total of 14 404 panoramic radiographs of 3- to 6-year-old children with deciduous dentition were collected from January 2023 to July 2024. The incidence of deciduous fused teeth was observed, and the abnormality of permanent teeth was recorded. SPSS 24.0 software was used for statistical analysis. RESULTS: The incidence of deciduous fused teeth was 3.06% (441/14 404). The order of dental position was as follows: mandibular deciduous incisors and cusp teeth fused (58.18%) > mandibular deciduous central and lateral incisors fused (30.91%) > maxillary deciduous central and lateral incisors fused (8.89%) > deciduous incisors and supernumerary teeth fused (2.02%). Deciduous fused teeth were found in 226 boys and 215 girls, with no significant difference between the sexes (P>0.05). We observed one pair (87.76%, 387/441) and two pairs (12.24%, 54/441) of fused teeth (54/441), respectively. A total of 287 pairs of fusion teeth on the right side more than 208 pairs on the left side, and the difference between them was statistically significant (P<0.01). More fusion teeth existed in mandibular deciduous teeth (443 pairs) than in maxillary ones (54 pairs), and the difference between them was statistically significant (P<0.01). More unilateral deciduous teeth (387 subjects) were found than bilateral ones (54 subjects), and the difference between them was statistically significant (P<0.01). Three types of deciduous fused teeth with inherited permanent teeth were observed as follows: 1) 49.49% (245/495) of inherited permanent teeth was absent, 2) 46.67% (231/495) of inherited permanent teeth was not absent, and 3) the number of fused permanent teeth accounted for 3.84% (19/495). CONCLUSIONS The incidence of deciduous fused teeth was 3.06%, mostly occurring in the lower anterior teeth region, with no gender difference. One pair of fused teeth is commonly observed, more often on the right than the left. These fusions occur more frequently in the mandible than the maxillary, and unilateral cases are more common than bilateral ones. Deciduous fused teeth had a certain impact on inherited permanent teeth. Pediatric dentists should pay attention to and closely observe whether any abnormality exists in the permanent dentition for early detection to prevent the harm caused by deciduous fused teeth.
Humans ; Tooth, Deciduous/abnormalities* ; Male ; Child ; Female ; Child, Preschool ; Dentition, Permanent ; Radiography, Panoramic ; Fused Teeth/diagnostic imaging* ; Incisor/diagnostic imaging* ; Tooth, Supernumerary/diagnostic imaging* ; Incidence ; Mandible

OBJECTIVES: This study aimed to evaluate the clinical application value of in-situ crown reattachment technique combined with pulpotomy in the treatment of complicated crown-root fractures in young permanent anterior teeth. METHODS: A prospective study was conducted on 50 children with complicated crown-root fractures in young permanent anterior teeth, who were treated at the Pediatric Dentistry Department, Hospital of Stomatology, Xi'an Jiaotong University from June 2023 to June 2024. All patients underwent in-situ crown reattachment technique combined with pulpotomy. Clinical examinations, radiographic evaluations, and subjective satisfaction surveys (using a Likert scale of 1-10) were conducted at 1, 6, and 12 months postoperatively. Data were analyzed using SPSS 23.0. RESULTS: The loss-to-follow-up rate was 12% (6/50), with 44 cases completing the 12 months of evaluation. The clinical success rate was 93.18% (41/44), and the radiographic success rate was 97.73% (43/44). The subjective satisfaction scores showed a significant improvement in masticatory function from 7.03±0.52 at 1 month to 8.07±0.92 at 12 months postoperatively (P<0.05), whereas the scores for aesthetics, comfort, and quality-of-life impact showed no statistically significant differences (P>0.05). CONCLUSIONS In-situ crown reattachment technique combined with pulpotomy effectively treats complicated crown-root fractures in young permanent anterior teeth, demonstrating a high short-term clinical success rate, significantly improved masticatory function, and minimally invasive preservation of pulp vitality and root development potential. This technique provides an optimized treatment option for dental trauma in children, although its long-term efficacy requires further validation.
Humans ; Pulpotomy ; Tooth Fractures/surgery* ; Child ; Prospective Studies ; Male ; Female ; Tooth Root/injuries* ; Tooth Crown/injuries* ; Treatment Outcome ; Incisor/injuries* ; Child, Preschool

This report presents a case of a 9-year-old child with a complicated crown-root fracture of the maxillary central incisor, accompanied with a root fracture. The treatment strategy was minimally invasive, focusing on vital pulp preservation, root fracture recovery, and crown restoration. The fractured crown was reattached using resin short posts to enhance retention, resulting in aesthetic and functional restoration of the anterior teeth. A 2-year follow-up revealed favorable clinical and radiographic outcomes.
Humans ; Child ; Tooth Fractures/therapy* ; Tooth Root/injuries* ; Incisor/injuries* ; Tooth Crown/injuries* ; Post and Core Technique ; Dental Restoration, Permanent/methods* ; Maxilla

Dental trauma is one of the relatively common emergencies in clinical dental practice, with a high incidence rate, and the maxillary central incisors are the most frequently affected. This article reports a case of a 17-year-old female patient who suffered traumatic complete avulsion of teeth 11 and 21, with tooth 21 lost after avulsion. The prognosis for replantation was poor due to the absence of the buccal alveolar bone wall of tooth 11. Therefore, tooth 11 was treated with extracorporeal root canal therapy and then replanted into the alveolar socket of tooth 21, which had better conditions, followed by elastic splint fixation. After 20 months of follow-up observation, the affected tooth maintained a stable functional position, with no periapical inflammation or ankylosis observed. Subsequently, delayed implant restoration at the site of tooth 11 was performed, ultimately achieving a favorable treatment outcome. This case may provide new insights and references for future clinical practices in tooth replantation.
Humans ; Female ; Tooth Replantation/methods* ; Incisor/injuries* ; Adolescent ; Tooth Avulsion/therapy* ; Maxilla ; Root Canal Therapy

OBJECTIVES: This study aimed to analyze the correlations and proportional relationships between maxillary anterior teeth (MAT) and facial measurements in Han Chinese individuals with the most attractive smiles, as evaluated by dental professionals. METHODS: Ten dentists with more than 5 years of clinical experience from different professional directions in a tertiary stomatological hospital were selected to evaluate the smile attractiveness of volunteers by visual analogue scale (VAS). Eighty-eight Han volunteers with the most attractive smile were selected. The perceived width of the MAT, the dimensions (height and width) of the maxillary central incisors (MCI), and the facial dimensions (intercanthal distance, interzygomatic distance, interalar distance, facial height and lower facial height) of the volunteers were measured on the frontal photos of the smile, digital oral model, and 3D face model. Pearson correlation analysis was performed to analyze linear correlations, and regression analysis was carried out to explore the proportional relationships. Reliability analysis using the intraclass correlation coefficient verified the stability of these proportional relationships. In addition, the correlations between MAT perceived width and the proportional relationships of (MCI) height to width ratio, with facial dimensions were explored and their reliability was verified. RESULTS: In Han Chinese individuals with the most attractive smiles, as evaluated by dental professionals, the Pearson correlation coefficients among MAT perceived widths were 0.813, 0.389, and 0.560. A proportional relationship existed between the lateral incisor and central incisor, and the ratio was 0.729. No significant correlations were found between MCI and the inner canthal distance, zygomatic distance, interalar distance, facial height, or the lower one-third facial height except for a negative correlation (r=-0.357) between MCI height and facial height in males and a positive correlation (r=0.249) between MCI width and interalar width when genders were combined. CONCLUSIONS Correlations exist among MAT perceived widths in Han Chinese individuals with the most attractive smiles, as evaluated by dental professionals. Partial correlations are observed between MCI height and width and facial measurements. The perceived width of the lateral incisor can serve as a reference indicator for predicting the perceived width of the central incisor, providing a reference for the aesthetic restoration of MAT in the Han ethnicity population.
Adult ; Female ; Humans ; Male ; China ; Esthetics, Dental ; Face/anatomy & histology* ; Incisor/anatomy & histology* ; Maxilla/anatomy & histology* ; Smiling ; East Asian People

Tooth resorption is the degradation of dental hard tissue due to the continuous action of odontoclasts. External cervical resorption refers to the cervical resorption of a tooth due to destruction and/or defects of the periodontal ligament or subepithelial cementum. In this paper, we report a case of maxillary central incisor with external cervical resorption after dental trauma and orthodontic treatment. The resorption site and morphology of the affected tooth were thoroughly analyzed by cone beam computed tomography prior to the operation. Dental operating microscope and layered external repair with composite resin and bioceramics ensured a perfect restoration of the resorption, and the vital pulp was preserved. The 6-year follow-up indicated a favorable treatment effect.
Humans ; Composite Resins ; Cone-Beam Computed Tomography ; Incisor/surgery* ; Maxilla ; Microsurgery/methods* ; Tooth Resorption/etiology*

Dental trauma is a common oral condition in children. For single-type trauma to young permanent teeth, timely treatment often results in a high survival rate for both the teeth and the pulp. However, in cases of complex dental trauma or when supernumerary teeth are impacted near the apex of the injured tooth, the prognosis is less predictable. This article reports a case of root fracture in an immature maxillary permanent central incisor combined with impacted supernumerary tooth in the apical region. After supernumerary tooth extraction and pulp revascularization therapy, the case demonstrated a good treatment outcome over a nearly 10-year follow-up period.
Child ; Humans ; Incisor/injuries* ; Maxilla ; Tooth Extraction ; Tooth Fractures/complications* ; Tooth Root/injuries* ; Tooth, Impacted/surgery* ; Tooth, Supernumerary/surgery*

OBJECTIVE: To evaluate the changes of periodontal phenotype (width of keratinized gingiva, thickness and height of alveolar bone) of lower anterior teeth in patients with skeletal class Ⅲ malocclusion before and after the periodontal-orthodontic-orthognathic combined treatment. METHODS: In the study, 20 patients with skeletal class Ⅲ malocclusion (6 males and 14 females) completed the periodontal-orthodontic-orthognathic combined treatment were included from March 2017 to June 2022, with 39 central incisors, 40 lateral incisors and 40 canines. The mean age was (25.40±4.27) years (20-34 years). The mean follow-up time was (3.70±1.05) years from the beginning of periodontal corticotomy regenerative surgery (PCRS) to the end of the combined treatment. Cone-beam computed tomography (CBCT) was used to measure the thickness, area and height of alveolar bone by the same researcher, taken before the PCRS (T0), 6 months after the PCRS (T1), 12 months after the PCRS (T2), before the orthognathic surgery (T3), and after the periodontal-orthodontic-orthognathic combined treatment (T4). The periodontal clinical parameters were used to evaluate changes in the soft tissue by another researcher, measured before the PCRS (T0) and after the combined treatment (T4). Changes of soft and hard tissue were evaluated by the periodontal phenotype. RESULTS: The width of keratinized gingiva increased significantly (all P < 0.001) in lower anterior teeth, the central incisors, lateral incisors and canines increased by (1.82±1.57) mm, (2.03±1.48) mm and (2.05±1.27) mm, respectively. The proportion of thick periodontal biotype in the central and lateral incisors increased significantly (all P < 0.001), while the changes of periodontal biotypes in the lower canines were not obvious. The thickness of labial alveolar bone of lower anterior teeth all increased significantly after periodontal corticotomy regenerative surgery and the combined treatment (all P < 0.001). The area of labial alveolar bone of lower anterior teeth also increased significantly after the combined treatment (all P < 0.001). The whole area of labial and lingual alveolar bone of central and lateral incisors increased (P < 0.001), while the whole area of canines remained the same. All The height of the alveolar bone increased (all P < 0.001) on the labial side after the treatment. CONCLUSION The periodontal phenotypes of lower anterior teeth were significantly improved after the periodontal-orthodontic-orthognathic combined treatment in patients with skeletal Angle class Ⅲ malocclusion. The improvement was long-termly stable, and the periodontal risk was reduced.
Male ; Female ; Humans ; Malocclusion, Angle Class III/surgery* ; Oral Surgical Procedures ; Incisor ; Cone-Beam Computed Tomography/methods*

OBJECTIVE: To evaluate the decompensation effectiveness and alveolar bone remodeling of mandibular anterior teeth after preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusion using lateral cephalogram and cone-beam computed tomography (CBCT). METHODS: Thirty high-angle patients with skeletal class Ⅱ malocclusion who had received preoperative orthodontic treatment and orthognathic surgery in Peking University School and Hospital of Stomatology between Ja-nuary 2017 and August 2022 and had taken lateral cephalogram and CBCT before and after preoperative orthodontic treatment were selected. Items were measured with lateral cephalogram including: The lower central incisor (L1)-Frankfort plane angle (L1-FH), the L1-mandibular plane angle (L1-MP), the L1-nasion-supramental angle (L1-NB) and the vertical distance from the incisal edge of lower central incisor to NB line (L1-NB distance), etc. The incidence of dehiscence/fenestration and the length of dehiscence at labial side (d-La) and lingual side (d-Li) were measured using CBCT. Pearson correlation analysis was used to evaluate the correlation between the changes of d-Li of L1 and age, duration of preoperative orthodontic treatment and the cephalometric measurements before preoperative orthodontic treatment to screen out risk factors affecting the periodontal risk of preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusions. RESULTS: After preoperative orthodontic treatment, L1-FH, L1-MP, L1-NB and L1-NB distances changed by 11.56°±5.62°, -11.13°±5.53°, -11.57°±5.43° and (-4.99±1.89) mm, respectively, and the differences were all statistically significant (P < 0.05). Among the 180 measured mandibular anterior teeth, 45 cases with labial dehiscence/fenestration before preoperative orthodontic treatment (T0) had no longer labial dehiscence/fenestration after preope-rative orthodontic treatment (T1); 142 cases without lingual dehiscence/fenestration at T0 had lingual dehiscence/fenestration at T1. After preoperative orthodontic treatment, the d-La of lower lateral incisors (L2), lower canines (L3) and lower anterior teeth (L1+L2+L3) decreased by (0.95±2.22) mm, (1.20±3.23) mm and (0.68±2.50) mm, respectively, and the differences were statistically significant (P < 0.05); the d-Li of L1, L2, L3 and L1+L2+L3 increased by (4.43±1.94) mm, (4.53±2.35) mm, (3.19±2.80) mm and (4.05±2.46) mm, respectively, and the differences were statistically significant (P < 0.05). The increase of d-Li of L1 was positively correlated with L1-FH (r=0.373, P=0.042). CONCLUSION This study showed that high-angle patients with skeletal class Ⅱ ma-locclusion could achieve ideal decompensation effect of mandibular anterior teeth after preoperative orthodontic treatment with bilateral mandibular first premolars extracted, but the lingual periodontal risk of mandibular anterior teeth was increased. This risk could be correlated to L1-FH before preoperative orthodontic treatment, which should be paid more attention in the design of orthodontic-orthognathic surgical treatment.
Humans ; Malocclusion, Angle Class III ; Malocclusion, Angle Class II/surgery* ; Facial Bones ; Incisor ; Orthognathic Surgical Procedures ; Cone-Beam Computed Tomography ; Mandible