BMC Oral Health最新文献

Background: With the advancement of dental implant technology, implant placement in the maxillary posterior region has become a primary method for restoring missing teeth. However, due to factors such as significant maxillary sinus pneumatization and insufficient alveolar bone volume, implant displacement into the maxillary sinus occasionally occurs. Retained implants in the maxillary sinus may induce maxillary sinusitis and secondary systemic diseases such as pyelonephritis. The relevance of which has not yet been fully recognized and thoroughly studied.

Case presentation: A 47-year-old male patient presented to the nephrology department with urinary frequency and urgency with fever. He was diagnosed with pyelonephritis and given a standard antibiotic regimen, which did not effectively control his condition. Further examination revealed that the first implant on the right side was connected to the maxillary sinus, while the second implant had become completely displaced into the maxillary sinus, resulting in maxillary sinusitis. However, due to the limited field of view of the CBCT, the second implant was not detected during the initial examination. The patient was given a maxillary sinus foreign body removal with complete drainage and continued antibiotic therapy. The patient's maxillary sinusitis and pyelonephritis were cured and did not recur during the 8-year follow-up.

Conclusion: This case demonstrates the risk of maxillary sinusitis due to implant displacement into the maxillary sinus. Severe maxillary sinusitis with secondary systemic diseases is possible. Moreover, for maxillary sinusitis caused by dislodged implants, simple antibiotic treatment is often difficult to be effective, and the cause of the disease needs to be removed as early as possible.

Background: Accurate extraction of impacted teeth remains a technically demanding procedure. This study aimed to develop a model-based experimental protocol to assess the surgical accuracy of a dynamic navigation system (DNS) assisted extraction of impacted maxillary anterior teeth.

Methods: A standardized custom model simulating impacted maxillary supernumerary teeth was constructed. Preoperative planning, including the definition of osteotomy boundaries and tooth sectioning planes, was performed using integrated intraoral scanning and cone-beam computed tomography (CBCT) data. During surgery, the DNS guided critical surgical procedural steps, including tooth localization, osteotomy, and segmentation. Postoperative CBCT imaging was used to compare actual surgical outcomes with the preoperative plan by quantifying three-dimensional deviations. Outcome measures included root mean square (RMS) deviation, angular deviation, and other geometric discrepancies. Total osteotomy area and operative time were also recorded.

Results: Fourteen models were evaluated, with seven assigned to the DNS-assisted group and seven to the control group. Compared with the preoperative plan, the DNS group demonstrated significantly lower RMS deviation in segmentation plane accuracy than the control group (0.43 ± 0.18 mm vs. 0.85 ± 0.38 mm; P = 0.02). Angular deviation was reduced in the DNS group (8.97° vs. 14.76°; P = 0.04), along with curvature RMS (1.72 rad vs. 3.54 rad; P = 0.04) and maximum deviation (0.77 mm vs. 1.30 mm; P < 0.01).

Discussion: These results indicate that DNS-assisted extraction of impacted maxillary anterior teeth significantly enhances surgical accuracy compared with conventional techniques, improving procedural accuracy, stability, and overall safety.

Background: Extranodal natural killer/T-cell lymphoma, is a rare, aggressive lymphoma strongly associated with Epstein-Barr virus infection. Its clinical manifestations are often non-specific, and atypical presentations outside the nasal cavity, such as lip swelling or oral ulcers, can mimic benign oral conditions, leading to delayed diagnosis. Histological variability and tissue necrosis further hinder early diagnosis. Metagenomic next-generation sequencing (mNGS) has emerged as a useful adjunct for detecting pathogen-specific nucleic acids when conventional pathology is inconclusive.

Case presentation: A 39-year-old man presented with a one-month history of recurrent upper lip swelling and a persistent labial and hard palate ulcer. Examination revealed firm swelling of the upper lip, a U-shaped ulcer on the upper labial mucosa, and an ulcer on the right hard palate. Laboratory tests were normal. Considering the patient's recollection of a prior fish bone injury to the oral mucosa, we performed mNGS on biopsy tissue in addition to routine histopathology. mNGS revealed a high load of Epstein-Barr virus DNA, prompting targeted immunohistochemistry and in situ hybridization, which confirmed the presence of Epstein-Barr virus-encoded RNA in atypical lymphocytes, establishing the diagnosis of extranodal NK/T-cell lymphoma. PET/CT showed a hypermetabolic upper-lip mass without systemic spread. The patient was classified as Ann Arbor stage IE, group A. Treatment with two cycles of pegaspargase, gemcitabine, and oxaliplatin resulted in complete healing of oral lesions, followed by localized radiotherapy. No recurrence was observed at the eight-month follow-up.

Conclusions: This case illustrates that extranodal NK/T-cell lymphoma can present with isolated oral lesions, posing significant diagnostic challenges. Incorporating mNGS into the evaluation of suspicious or infection-like oral lesions expedite Epstein-Barr virus detection, guide targeted pathological workup, and reduce diagnostic delays, ultimately improving patient outcomes.