A Clinical Observation Study for Transnasal Endoscopic Marsupialization in the Treatment of Maxillary Cyst

The aim of this study was to investigate the feasibility and evaluate the clinical effects of transnasal marsupialization of maxillary cyst under nasal endoscope. Twenty patients with maxillary bone cysts were treated with endoscopic marsupialization. According to the location of the maxillary bone cyst, the opening window was selected in the nasal base or the inferior or middle nasal meatus. The cyst wall of the window was removed, and the fluid was drained out. The diameter of the opening window was more than 1 cm, so that the cyst and the maxillary sinus can be fused into a cavity. This ensured nasal drainage through the cyst cavity and nasal cavity or maxillary sinus. The patients were followed up for 6 to 18 months. No serious complications occurred. The cyst wall epithelialized 2 or 3 months after the operation, and the cyst cavity drained well with no recurrence. Intranasal marsupialization under a nasal endoscope is a feasible alternative for the treatment of maxillary cysts. It makes the procedure simple, safe, less traumatic, has definite clinical effects, and low recurrence rate. Especially suitable for maxillary cysts protruding into the nasal floor or maxillary sinus.

Radiographic bone volume alteration after jaw cyst enucleation with or without simultaneous bone grafts: A prospective randomized study

OBJECTIVE

This study was aimed to evaluate bone healing after jaw cyst enucleation with or without bone substitutes by cone beam computed tomography, and to analyze potential influence factors for bone formation as well.

MATERIALS AND METHODS

Sixty seven jaw cyst patients were randomly assigned to two groups. Thirty three patients in control group accepted cystectomy without any filling material. The rest 34 bone cavities which filled with xenograft (DBBM, Bio-Oss®) and covered by absorbable membrane (Bio-Gide®) were included in the guided bone regeneration (GBR) group. All patients were examined with cone bean computerized tomography before operation, 3 and 6 months after surgery. Linear regression analysis was applied to evaluate the influence factors of bone healing.

RESULTS

There was no significant difference in bone formation rate at 3 months after enucleation, with shrinkage rate (SR) of cystic lesion in control group and GBR group of 26.43 ± 14.98% and 20.78 ± 10.80%, respectively (p > 0.05). Larger shrinkage area in GBR group was detected on postoperative radiographs after 6 months with SR of 60.11 ± 19.23%, when compared to those in patients without filling (6 months SR: 48.63 ± 19.39%, p = 0.018, <0.05). Linear regression analysis showed that cyst size was negatively correlated with bone formation.

CONCLUSION

GBR with bovine xenograft and absorbable membrane showed considerable bone regeneration property in the healing of jaw cystic defects after enucleation of radicular cysts. Cyst size showed a suppressive influence on bone formation.

Eruption of the Permanent First Premolar Associated with a Mandibular Keratocystic Odontogenic Tumor after Marsupialization in a 9-year-old Boy: A Case Report with 2 years of follow-up

Amongst odontogenic cysts, keratocystic odontogenic tumor (KOT) is a benign intra-osseous lesion, characterized by corrugated parakeratinized uniform stratified squamous epithelium, with potential for aggressive behavior and high tendency to recur. There are multiple treatment modalities for this cyst. Some surgeons prefer the conservative treatments such as marsupialization while the others prefer invasive treatments such as radical resection. The aim of this study was to present a case of KOT involving the right mandibular premolar area with an impacted tooth in a 9-year-old boy treated by marsupialization. The treatment resulted in eruption of the mandibular first premolar, and no signs of recurrence were observed after two years. Marsupialization was found to be an effective treatment in inducing the eruption of mandibular premolar associated with KOT in preadolescents and can be a reliable procedure to reduce recurrence tendency of KOT.

Increased M2 Isoform of Pyruvate Kinase in Fibroblasts Contributes to the Growth, Aggressiveness, and Osteoclastogenesis of Odontogenic Keratocysts

To investigate the role of glycolysis and the M2 isoform of pyruvate kinase (PKM2) in odontogenic keratocysts (OKCs), the glycolytic flux of primary odontogenic keratocyst fibroblasts (OKC-Fs) and normal oral mucosa fibroblasts (OM-Fs) was determined by glucose uptake, lactate production, and cell proliferation assays. Wound healing assay and Matrigel-coated chamber system were used to investigate the effects of PKM2 on migration and invasion capacities of OKC-Fs. Co-culture of OKC-Fs with osteoclast precursors (RAW264.7 cells) was used to clarify the role of glycolysis in the osteoclastogenic effects of OKC-Fs. In addition, hypoxia-inducible factor 1α and some key enzymes related to glycolysis, including PKM2, 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3, hexokinase 2, and lactate dehydrogenase A, were detected to assess the activation of glycolysis in OKC stroma by immunohistochemistry. Results showed that the glucose uptake and lactate production were significantly higher in OKC-Fs than OM-Fs. PKM2 was elevated in OKC-Fs compared with that in OM-Fs. PKM2 significantly regulated glycolysis, proliferation, migration, invasion, and osteoclastogenic effects of OKC-Fs. Additionally hypoxia-inducible factor 1α, 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3, hexokinase 2, and lactate dehydrogenase A were markedly overexpressed in OKC stroma, and correlated with PKM2. Moreover, the expression of PKM2 was regulated by oxygen concentration in vitro. In sum, PKM2-mediated glycolysis regulated the growth, aggressiveness, and osteoclastogenesis of OKC.

Activation of mesenchymal stem cells promotes new bone formation within dentigerous cyst

Background

Dentigerous cyst (DC) is a bone destructive disease and remains a challenge for clinicians. Marsupialization enables the bone to regenerate with capsule maintaining, making it a preferred therapeutic means for DC adjacent to vital anatomical structures. Given that capsules of DC are derived from odontogenic epithelium remnants at the embryonic stage, we investigated whether there were mesenchymal stem cells (MSCs) located in DC capsules and the role that they played in the bone regeneration after marsupialization.

Methods

Samples obtained before and after marsupialization were used for histological detection and cell culture. The stemness of cells isolated from fresh tissues was analyzed by morphology, surface marker, and multi-differentiation assays. Comparison of proliferation ability between MSCs isolated from DC capsules before (Bm-DCSCs) and after (Am-DCSCs) marsupialization was evaluated by Cell Counting Kit-8 (CCK-8), fibroblast colony-forming units (CFU-F), and 5′-ethynyl-2′-deoxyuridine (EdU) assay. Their osteogenic capacity in vitro was detected by alkaline phosphatase (ALP) and Alizarin Red staining (ARS), combined with real-time polymerase chain reaction (RT-PCR) and immunofluorescence (IF) staining. Subcutaneous ectopic osteogenesis as well as cranial bone defect model in nude mice was performed to detect their bone regeneration and bone defect repairability.

Results

Bone tissue and strong ALP activity were detected in the capsule of DC after marsupialization. Two types of MSCs were isolated from fibrous capsules of DC both before (Bm-DCSCs) and after (Am-DCSCs) marsupialization. These fibroblast-like, colony-forming cells expressed MSC markers (CD44+, CD90+, CD31−, CD34−, CD45−), and they could differentiate into osteoblast-, adipocyte-, and chondrocyte-like cells under induction. Notably, Am-DCSCs performed better in cell proliferation and self-renewal. Moreover, Am-DCSCs showed a greater osteogenic capacity both in vitro and in vivo compared with Bm-DCSCs.

Conclusions

There are MSCs residing in capsules of DC, and the cell viability as well as the osteogenic capacity of them is largely enhanced after marsupialization. Our findings suggested that MSCs might play a crucial role in the healing process of DC after marsupialization, thus providing new insight into the treatment for DC by promoting the osteogenic differentiation of MSCs inside capsules.

Salvage of Dental Implant Located in Mandibular Odontogenic Cyst. A Conservative Surgical Treatment Proposal

The aim of this case report was to evaluate the use of Partsch I cystotomy in order to preserve a dental implant located in an odontogenic cyst extended from 3.2 to 4.4. A 50 year-old woman showed a circular, well-defined unilocular radiolucent area, Ø2.5 cm, in the right mandibular region with an oral implant intruding inside it. The overdenture in the mandibular right site showed no clinical mobility. The authors decided to perform a surgical treatment aimed to preserve the implant. The patient underwent Partsch I surgery followed by iodoform gauze insertion replaced weekly for one month, revision of the previous orthograde endodontic treatments, and an acrylic resin obturator prosthesis application for the following two months. The twelve month follow-up showed no clinical mobility of the right lateral mandibular implant prostheses. Radiographical analysis revealed cystic lesion healing and perimplant bone regeneration. This report highlights the opportunity to apply cystotomy when the cyst involves a dental implant and undermines its stability. This possibility is offered by the peculiar clinical scenario where the implant was stabilized by the presence of a previous prosthetic fixation. Our study led to the application of an operative protocol that allowed for the preservation of the implant.

Comprehensive orthodontic treatment of a young girl with an odontogenic keratocyst and impacted teeth in the mandible

Odontogenic keratocysts (OKCs) are one of the most aggressive cysts in the oral and maxillofacial area because of their high recurrence rate and infiltrative behavior. In growing patients with OKCs, a radical treatment approach might cause numerous complications, including the disturbance of jaw growth and loss of the involved tooth. This case report describes successful comprehensive orthodontic treatment combined with marsupialization of the cyst in a young girl who exhibited an OKC with impacted teeth. The 10-year-old girl presented with an OKC extending from the mandibular symphysis through the left mandibular body, with ectopic impaction of the mandibular left canine and first premolar, as well as congenitally missing bilateral mandibular second premolars. Interestingly, spontaneous improvement of the positions of the ectopic impacted teeth, along with a reduction in the size of the cyst, occurred during marsupialization. The sequential use of removable and fixed appliances enabled orthodontic traction of the impacted teeth. The treatment outcome was stable at 2.5 years after the end of the treatment. We speculate that comprehensive orthodontic treatment combined with marsupialization can be an effective treatment strategy for patients with OKCs, especially when they are encountered in young, growing patients with impacted teeth.