Clinical retrospective study of dental implant removal: do patients who require implant removal desire implant prosthesis again?

Background

This study investigated the causes of dental implant removal due to complications, and examined whether patients who had dental implant removal desired re-implant prosthesis treatments.

Material and Methods

A retrospective case–control study was conducted on patients who had their dental implants removed. We investigated whether the removed dental implant was replaced with other implant prostheses. Age, sex, diabetes, smoking, implant site distribution, reason for implant removal, and blade and root-form implants were categorized as predictive variables. The outcome variable was desire for re-implantation or use of other prosthetic methods after implant removal. A logistic regression model was created to identify patient factors that could predict the re-implantation of dental prostheses after implant removal.

Results

A total of 215 dental implants were removed from 143 patients. The most common reason for implant removal was peri-implantitis that was identified in 165 implants. After implant removal, re-implantation was performed in 98 implants (45.6%). Bivariate analyses showed that age, diabetes, implant type, and reason for implant removal were associated with the desire for re-implanted prostheses. The multiple regression model revealed that age, implant type, and reason for implant removal were associated with an increased desire for re-implant prostheses after implant removal.

Conclusions

Re-implantation of prostheses after the removal of dental implants was desired by patients who were younger, had implants placed in the root form, and had implants removed due to prosthetic-related complications.

Key words:Dental implant removal, complications, implant prosthesis, retrospective study, re-implantation.

Dasatinib Is an Effective Treatment for Angioimmunoblastic T-cell Lymphoma

Recurrent hotspot (p.Gly17Val) mutations in RHOA encoding a small GTPase, together with loss-of-function mutations in TET2 encoding an epigenetic regulator, are genetic hallmarks of angioimmunoblastic T-cell lymphoma (AITL). Mice expressing the p.Gly17Val RHOA mutant on a Tet2-null background succumbed to AITL-like T-cell lymphomas due to deregulated T-cell receptor (TCR) signaling. Using these mice to investigate therapeutics for AITL, we found that dasatinib, a multikinase inhibitor prolonged their survival through inhibition of hyperactivated TCR signaling. A phase I clinical trial study of dasatinib monotherapy in 5 patients with relapsed/refractory AITL was performed. Dasatinib was started at a dose of 100 mg/body once a day and continued until days 10-78 (median day 58). All the evaluable patients achieved partial responses. Our findings suggest that AITL is highly dependent on TCR signaling and that dasatinib could be a promising candidate drug for AITL treatment. SIGNIFICANCE: Deregulated T-cell receptor signaling is a critical molecular event in angioimmunoblastic T-cell lymphoma and can be targeted with dasatinib.

[Blastic plasmacytoid dendritic cell neoplasm accompanied by chronic myelomonocytic leukemia successfully treated with azacitidine]

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare disease that develops with a skin lesion and is often accompanied by leukemic transformation. The normal counterparts of BPDCN tumor cells are progenitors of plasmacytoid dendritic cells, whereas the origins are thought to be hematopoietic stem cells. Approximately 10%-20% of BPDCN patients develop other hematologic malignancies, including chronic myelomonocytic leukemia (CMML). Mutations in epigenetic regulators are frequently observed in both BPDCN and CMML tumors. Azacitidine, a drug that targets epigenetic dysregulation, is known to be an effective treatment for CMML. However, it has been used in few BPDCN patients. Here, we report a BPDCN patient with skin lesions, bone marrow infiltration, and lymphadenopathy. CMML also developed during the course of BPDCN. Azacitidine had positive effects on CMML; however, BPDCN aggressively relapsed during treatment. Two TET2 mutations were found in both BPDCN and CMML tumors; one of which was commonly identified in both tumors.

[Fatal exacerbations of chronic active Epstein-Barr virus infection subsequent to cytotoxic chemotherapy]

Chronic active Epstein-Barr virus infection (CAEBV) is critical owing to lethal complications such as hemophagocytic lymphohistiocytosis (HLH), multiple organ failure, and malignant lymphoma. Here we present two cases of CAEBV who developed rapid and life-threatening disease progression after cytotoxic chemotherapy. Case 1: In a 34-year-old male, CAEBV recurred after 4-month remission obtained by initial therapy with etoposide, cyclosporine, and prednisolone. Accordingly, cord blood transplantation was planned. A day after administering high-dose melphalan as the conditioning, he developed respiratory failure, pancytopenia, and hyperferritinemia. He died 3 days later. Case 2: A 53-year-old female attained remission after initial therapy for CAEBV. After 1 month, she relapsed, and high-dose cytarabine (HDAC) was administered. A day after HDAC administration, she suddenly developed respiratory failure, which was followed by multiple organ failure. She died 3 days later. Thus, planned strategy for prompt allogeneic hematopoietic stem cell transplantation is necessary to prevent disease progression and control cytokinemia before cytotoxic chemotherapy for CAEBV.

What are the risk factors for postoperative infections of third molar extraction surgery: A retrospective clinical study?

BACKGROUND

This study aimed to identify (1) the predilection site of postoperative infection after third molar extraction surgery, (2) risk factors associated with postoperative infection, and (3) the cause of the difference between delayed- and early-onset infections.

MATERIALS AND METHODS

This retrospective study included 1010 patients (396 male, 614 female) who had ≥1 third molars extracted (2407; 812 maxilla, 1595 mandible). The risk factors were classified as attributes, general health, anatomic, and operative. Outcome variables were delayed- and early-onset infections.

RESULTS

Postoperative infection was completely absent in the maxilla, and all infections occurred in the mandible, with a probability of 1.94% (31/1595). Bivariate analysis for postoperative infection showed depth of inclusion and intraoperative hemostatic treatment to be significantly associated with the development of infections. Bivariate analysis for delayed- and early-onset infections showed simultaneous extraction of the left and right mandibular third molars to be prominent risk factors.

CONCLUSIONS

Postoperative infection occurs mainly in the mandible, and that in the maxilla is very rare. The risk of postoperative infection in the mandible was found to be related to the depth of inclusion and intraoperative hemostatic treatment. Simultaneous extraction of the left and right mandibular third molars appear to increase the risk of delayed-onset postoperative infection.

Mandibular fracture patterns consistent with posterior maxillary fractures involving the posterior maxillary sinus, pterygoid plate or both: CT characteristics

OBJECTIVES

The aim of this study was to determine the incidence of posterior maxillary fractures involving the posterior maxillary sinus wall, pterygoid plate or both, unrelated to major midface fractures in patients with mandibular fractures, and to characterize associated fractures.

METHODS

A CT study was performed in patients with mandibular fractures to identify posterior maxillary fractures. Patients aged under 16 years, those with mandibular fractures involving only dentoalveolar components and those with concurrent major midfacial fractures were excluded.

RESULTS

13 (6.7%) of 194 patients with mandibular fractures also had posterior maxillary fractures (case group). The injury pattern correlated with the external force directed to the lateral side of the mandible (p < 0.001), alcohol consumption (p = 0.049), the presence of multifocal fractures (p = 0.002) and the fracture regions in the symphysis/parasymphysis (p = 0.001) and the angle/ramus (p = 0.001). No significant difference between the case and non-case groups was seen for age, sex or cause of trauma. Non-displaced fractures in the ipsilateral posterior mandible occurred with significant frequency (p = 0.001) when the posterior maxillary fractures involved only the sinus.

CONCLUSIONS

Mandibular fractures accompanied by posterior maxillary fractures are not rare. The finding of a unilateral posterior maxillary fracture on CT may aid the efficient radiological examination of the mandible based on possible patterns of associated fractures, as follows: in the ipsilateral posterior region as a direct fracture when the impact is a medially directed force, and in the symphysis/parasymphysis or contralateral condylar neck as an indirect fracture.

The retromandibular transparotid approach for reduction and rigid internal fixation using two locking miniplates in mandibular condylar neck fractures

We evaluated the safety, efficacy, and morbidity associated with the treatment of displaced mandibular condylar neck fractures using a retromandibular transparotid approach to reduce and rigidly fix using two 2.0-mm locking miniplates. Our surgical inclusion criteria were: patient selection of open reduction and fixation, displaced unilateral condylar fractures with derangement of occlusion, and bilateral condylar fractures with an anterior open bite. The study group consisted of 19 patients who underwent surgery for 19 mandibular condylar neck fractures; patients were analyzed prospectively, with more than 6 months of follow-up, and were evaluated in terms of functional results, scar formation, postoperative complications, and stability of fixation. The results showed that functional occlusion identical to the preoperative condition and correct anatomical reduction of the condylar segments in centric occlusion, followed by immediate functional recovery, was achieved in all patients. No patient suffered from any major or permanent complication postoperatively, although there were two cases (11%) of temporary facial nerve palsy, which resolved completely within 3 months. Surgical scars were barely visible. The retromandibular transparotid approach with open reduction and rigid internal fixation for displaced condylar neck fractures of the mandible is a feasible and safe, minimally invasive surgical technique that provides reliable clinical results.

[Breast cancer associated with other organ cancer reviewed from cancer family history]

Double cancers and related family histories were studied in eight patients who had developed cancers in the breasts and other organs. The incidence of double cancer among patients with breast cancer was 1.7% (8/472), and the age at first onset averaged 48. The organs involved were mainly the digestive system, thyroid and female sexual organs. The incidence of cancer was higher in the pedigree of double breast cancer patients than in those with solitary cancer. In follow-up study, it is necessary to elucidate the difference in characteristics between double and solitary breast cancer.