Introduction: Ectopic foreign bodies in the maxillary sinus occur rarely. Ectopic tooth eruption rarely occurs in the orbit, nasal cavity, maxillary sinus, and elsewhere. Ectopic eruption of teeth in the maxillary sinus is most commonly associated with wisdom teeth and is rarely associated with supernumerary teeth. This rare phenomenon may be accompanied by chronic recurrent sinusitis with headaches and facial pain. However, fibro-osseous lesions in the paranasal sinuses are discovered incidentally on X-ray images and are often asymptomatic. Osteoma is the most common fibro-osseous lesion that develops in the paranasal and nasal sinuses. Osteomas rarely cause serious symptoms such as orbital lesions and intracranial invasion. Case Presentation: We report a rare case of exostosis containing supernumerary teeth within the maxillary sinus. A characteristic pedicled bone lesion with a clear border on computed tomography was the undefined orthopantomogram radiopacity in the maxillary sinus, and the lesion contained supernumerary teeth. As the patient had chronic nasal congestion, the tumor was surgically removed. Pathologically, the surgical specimen revealed an osteoma. The patient\'s symptoms of chronic sinusitis disappeared. Because the patient had no history of midface trauma or surgery, the supernumerary teeth were speculated to have migrated during a reactive osteogenic process caused by chronic sinusitis. Conclusions: A foreign body in the maxillary sinus can be easily diagnosed by computed tomography. Surgical removal is recommended if the foreign body is symptomatic or occupies more than half of the maxillary sinus. This can help resolve chronic sinusitis symptoms and prevent serious complications in the future.

Ectopic eruption of the second permanent molar is a tooth replacement disorder during adolescence. If not treated in time, it can cause hard tissue of the adjacent first molar resorption, early tooth loss, decreased chewing efficiency, and other serious malocclusions. Timely detection and treatment of ectopic eruption of the second permanent molar are of great significance in preventing malocclusions in adolescents and establishing normal occlusion relationships. However, current case reports on the ectopic eruption of the mandibular second molar are relatively rare and are mostly concentrated on surgical and orthodontic treatments, and long-term follow-up is lacking. This paper reports a case in which brass wire ligation was used to treat ectopic eruption of the mandibular second permanent molar, allowing the permanent teeth to erupt smoothly and establish a normal occlusion. The patient was observed for five years after the operation. The occlusion was stable, and the tooth root development, pulp vitality, and periodontal conditions were normal. This paper provides a clinical approach that is short in treatment duration, simple, and minimally invasive for young mandibular second permanent molars with moderate mesial inclination and partial eruption. This method is of importance in helping children establish physiological occlusion.
第二恒磨牙异位萌出若未得到及时治疗，会导致相邻的第一磨牙牙体组织吸收、牙齿早失、咀嚼效率下降及其他严重的错牙合畸形。及时发现和处理第二恒磨牙异位萌出，对预防青少年错牙合畸形、建立正常咬合关系具有重要的意义。然而，目前针对下颌第二恒磨牙异位萌出的病例报告比较少见，大多治疗方法主要为手术及正畸的方式，且缺乏长期的随访。本文报道1例采用铜丝结扎法治疗下颌第二恒磨牙异位萌出，使恒牙顺利萌出并建立正常咬合。术后观察5年，咬合稳定，牙根发育、牙髓活力及牙周状况正常。本文为近中倾斜度不大且已经部分萌出的阻生年轻下颌第二恒磨牙提供一种治疗周期短、简便及微创的临床思路。.

UNASSIGNED: The etiology of the ectopic eruption (EE) of the maxillary first permanent molars (FPM) remains unclear and controversial. This study was designed to explore the dental and skeletal factors for EE of the FPM in children.
UNASSIGNED: Children aged 6-10 years were recruited to this study. Subjects were assigned to the ectopic eruption group (EEG) and the normal eruption group (NEG). Lateral cephalometric radiographs and panoramic radiographs were measured by angular and linear indices.
UNASSIGNED: The prevalence of EE of maxillary FPM was higher in males and at younger ages. Subjects with skeletal class III malocclusion were more likely to be diagnosed with EE of maxillary FPM. The SNA, ANB, FMIA, Wits, Ptm-A, ANS-PNS, overbite, and overjet were significantly different between the EEG and the NEG. The length of the posterior region of the maxillary alveolar bone, U6-OP, and eruptive angulation of the maxillary FPM were statistically different between the two groups.
UNASSIGNED: Male sex, skeletal class III malocclusion, mesial inclination of the maxillary FPM, hypoplasia of the maxilla, and insufficient length of the posterior region of the maxillary alveolar bone were related to EE of the maxillary FPM.

暂无摘要。

Background Early detection and management of ectopic eruption (EE) of first permanent molars (FPMs) are crucial to avoid complicated treatments later. Aim This study aimed to assess the prevalence and severity of EE of FPMs among children in Makkah, Saudi Arabia. Methods This retrospective study was based on a radiographic evaluation of 1,008 dental panoramic radiographs performed for children attending the Dental Educational Hospital at Umm Al-Qura University and the Security Forces Hospital in Makkah. Patients\' age, sex, tooth location, and severity of EE were assessed. The study adhered to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline for cross-sectional studies.  Results Of the 1,008 reviewed cases, 18 (1.79%) were diagnosed with EE of FPMs. Among the 11 male patients, 81.82% showed severe EE, while 57.14% exhibited moderately severe EE among the seven female patients. The prevalences of EE in the maxilla and mandible were 1.59% and 0.20%, respectively. In contrast, the occurrence of EE of FPMs was similar between the right and left sides. Conclusion In this study, the prevalence of EE of FPMs among children in Makkah was 1.79%. The frequency and severity were both greater in male patients compared to female patients. While significantly more EE of FPMs was observed in the maxilla than in the mandible, there was no significant difference between the right and left sides.

The main objective of the present research study is to evaluate the association between the occurrence of buccally displaced canine (BDC) and the palatal as well as the craniofacial morphology in adolescents in accordance at the early permanent dentition. As the experimental group, 100 adolescents of Chinese ethnicity (mean age 13.05 years) with crowding and buccally displaced canine (BDC-c) were selected in comparison with the same number of candidates (mean age 12.59 years) without BDC and crowding as control group. Digital dental casts and cephalograms were collected for three dimensional (3D) and cephalometric measurements. An independent sample T-test was used to compare the cephalometric values between the two groups. Logistic regression as commonly statistical methods used in empirical study including categorical dependent variables was used to identify the joint effects of the dental variables\' 3D measurements. When comparing the groups with above analysis, patients with BDC showed a statistically significant narrower and higher palatal vault. For the cephalometric variables, the anterior cranial base length, sagittal position of the maxilla (SNA), sagittal position of the mandible (SNB), and skeletal relationship between maxilla and mandible (ANB) appeared to be smaller, whilst palatal plane angle (SN-PP), Frankfort-mandibular plane angle (FMA), anterior facial height, and lower facial height were larger in BDC-c control group (p < 0.05). A smaller inter-first premolar width was significant in the prediction model (p = 0.002). This study highlights that BDC-c participants in early permanent dentition exhibited a narrower dental arch and higher palatal vault, of which a smaller inter-first premolar width would significantly increase the occurrence of BDC.

OBJECTIVE: This study aimed to describe clinical and imaging analysis of supernumerary teeth in the mandibular region of 22 cases.
METHODS: Retrospective study.
METHODS: This study enrolled patients diagnosed with supernumerary teeth who underwent cone beam computed tomography (CBCT) at Stomatology Hospital of Xi\'an Jiaotong University from August 2016 to September 2022. Participants included individuals aged 7-29 years of both genders. The following variables were examined: number of supernumerary teeth, location, shape, direction, length, relationship with adjacent teeth and surrounding anatomical structures, and secondary effects.
RESULTS: Out of 236 subjects, 22 (6.02%) were found to have supernumerary teeth in the mandibular region, with a total of 62 teeth identified. The male-to-female ratio was 5:6. Most supernumerary teeth were located in the lingual side of the mandibular region, particularly in the 34-35 tooth area (21.66%), followed by the 44-45 tooth region. The vast majority of supernumerary teeth (96.77%) were impacted, and more than half (51.67%) were located near the mental nerve canal. The average length of the supernumerary teeth was 10.5 mm. While no primary complications were observed, some secondary symptoms were noted, such as the ectopic eruption of adjacent teeth and crowding of permanent teeth.
CONCLUSIONS: The supernumerary teeth in the mandibular area have regional characteristics, which can provide for clinical diagnosis and treatment. CBCT can accurately analyze the location of supernumerary teeth and their secondary effects, and provides the treatment plan on that basis.

UNASSIGNED: To evaluate the null hypothesis that there is no difference in a set of clinical predictors of potentially impacted canines between low-risk patients with and without displaced canines.
UNASSIGNED: The normal canine position group consisted of 30 patients with 60 normally erupting canines ranked in sector I (age, 9.30 ± 0.94 years). The displaced canine group comprised 30 patients with 41 potentially impacted canines ranked in sectors II to IV (age, 9.46 ± 0.78 years). Maxillary lateral incisor crown angulation, inclination, rotation, width, height, and shape, as well as palatal depth, arch length, width, and perimeter composed a set of clinical predictors, which were evaluated on digital dental casts. Statistical analyses consisted of group comparisons and variable correlations (p < 0.05).
UNASSIGNED: There was a significant association between sex and mesially displaced canines. Unilateral canine displacement was more prevalent than bilateral displacement. The crown of the maxillary lateral incisors was significantly angulated more mesially and rotated mesiolabially in low-risk patients with displaced canines, who also had a shallower palate and shorter anterior dental arch length. Lateral incisor crown angulation and rotation, as well as palatal depth and arch length, were significantly correlated with the canine displacement severity.
UNASSIGNED: The null hypothesis was rejected. Maxillary lateral incisor angulation inconsistent with the \"ugly duckling\" stage as well as a shallow palate and short arch length are clinical predictors that can significantly contribute to the early screening of ectopic canines in low-risk patients.

Ectopic eruption of the permanent first molar can lead to malocclusion if left untreated. Despite several reported etiologic factors and treatment options, ectopic eruption caused by an improper restoration on an adjacent tooth and a simple solution have never been documented. Case report: An 8-year-old boy presented with an entrapped ectopic permanent mandibular first molar under the poorly adapted margin of a preformed metal crown (PMC) on the adjacent primary second molar. Replacement with a PMC that had well-contoured margins followed by inserting a separating module between the proximal contact of the two teeth resulted in successful management of this situation in 1 month. Conclusion: This simple approach with good interdisciplinary communication is practical for correcting eruption problems due to a poorly adapted PMC, with long-term satisfactory results. To avoid subsequent malocclusion and unnecessary treatments, dental practitioners must be vigilant when manipulating PMCs and assessing the marginal adaptation prior to their cementation.

Ectopic eruption results from a disturbance in tooth development and eruption, leading to an erupted or non-erupted tooth being in an unexpected anatomical location. This retrospective case series describes the location, position, form, and clinical signs associated with ectopic eruption in dogs. Thirty-five dogs (46 teeth) were diagnosed with ectopic eruption at three clinical practices during 2017-2020. The cases were described in terms of the location, the development and eruption status, the clinical signs, the consequences, and the treatment performed. The collected data were statistically analyzed to establish possible ramifications. The results showed that the ectopic eruption in the evaluated cases involved permanent teeth, mainly located in the maxilla, and mostly unerupted. Those located in the mandible were significantly more impacted than those located in the maxilla. This study concluded that tooth crowding and malocclusion (39.1%), facial swelling (8.6%), and periodontal disease (8.6%) were associated with the presence of ectopic eruption, and consequently, treatment was required in the majority (65.2%) of cases.