Quintessence International, 08/2015

The use of cone beam computed tomography (CBCT) in endodontics has been extensively reported in the literature. Compared with the traditional spiral computed tomography, limited field of view (FOV) CBCT results in a fraction of the effective absorbed dose of radiation. The purpose of this manuscript is to review the application and advantages associated with advanced endodontic problems and complications, while reducing radiation exposure during complex endodontic procedures. The benefits of the added diagnostic information provided by intraoperative CBCT images in select cases justify the risk associated with the limited level of radiation exposure. Keywords: cone beam computed tomography, dental trauma, intraoperative, outcome, root resorption

Peri-implant mucosal recessions can be a major esthetic problem in the anterior zone, whereas in the functional zone the coverage of exposed implants is not of primary significance, as methods to clean these structures are more important. In these situations free gingival grafts are often used to deepen the vestibule and increase the amount of attached keratinized mucosa. Complete coverage of mucosal recessions around dental implants is still a challenging procedure, but it seems that recessions up to 2 mm can be successfully grafted with subepithelial connective tissue grafts. Keywords: attached keratinized mucosa, free gingival graft, implant dehiscence, recession coverage

Objective: In recent years, photodynamic therapy (PDT) using a combination of photosensitizer and laser light source has been used in periodontal therapy. The aim of this review is to provide an overview of the current status and use of PDT. Data Sources: A review of pertinent literature was carried out in PubMED to determine the current position of PDT applications in periodontal and peri-implant diseases. Conclusions: In spite of different results and suggestions from various researchers, the present review showed that use of PDT may help improve periodontal outcomes. Therefore, it could become a new method for antibacterial treatment and may be used as an adjunct to or as conventional therapy for the treatment of periodontal and peri-implant diseases. Based on the results presented herein, there is promising, albeit preliminary, information regarding the benefits of PDT use on periodontal treatment outcomes. However, the conclusions are a reflection of a relatively small sample size and therefore need to be demonstrated in the general population. Clinical Relevance: Periodontal diseases and peri-implantitis are among the specific targets where PDT can be applied. Keywords: dental implants, periodontitis, photodynamic therapy, photosensitizer

Objective: A long-term clinical study previously stated that adhesively luted resin-bonded fixed partial dentures (RBFPDs) with two retainers exhibited two complications (loss of adhesion or fracture between retainer and pontic) when compared to RBFPDs with a single retainer. The reasons for these complications were not reported. The aim of this study was to evaluate the stress distribution of two-retainer and singleretainer zirconium dioxide RBFPDs by using three-dimensional finite element analysis (3D FEA). Method and Materials: Two different 3D finite element models were created. Each model contained cortical bone, cancellous bone, periodontal ligament, cement, and enamel. Additionally one of the models contained a two-retainer zirconium dioxide RBFPD while another contained a single-retainer zirconium dioxide RBFPD. A 100 N force was applied at 45 degrees 2 mm below the incisal edge of the palatal surface of the pontic. In each model, Von Mises stress distribution was evaluated. Results: Maximum Von Mises stress values in RBFPD with a single retainer and two retainers were 1.13 MPa and 1.23 MPa, respectively. Von Mises stress was concentrated at the interface between pontic and retainer for RBFPD with two retainers. Conclusion: Zirconium dioxide RBFPD with a single retainer and two retainers exhibited similar stress concentrations between pontic and retainer. However, the use of a single retainer for RBFPDs prevented stress concentration at the interface between retainer and pontic. Keywords: finite element analysis, resin-bonded fixed partial denture with single retainer, stress analysis, zirconium dioxide

Controversy exists regarding the general safety of resin sealants and in particular their use in children, due to the possible leaching of non-polymerized monomers including bisphenol A. A thermally cured high-viscosity glass-ionomer cement (GIC) is suggested as a first-choice sealant material. An innovative approach of thermo-curing the GIC during placement is presented. The step-by-step clinical procedure and rationale for the biomimetic thermo-cured glass-ionomer fissure sealant are introduced and described. A thermally cured GIC sealant may provide long-term caries protection to fissures and pits without the need to maintain and reseal. GICs are both biocompatible and biomimetic resulting in formation of fluorapatite, the ultimate protection against dental caries. Keywords: glass ionomer, pediatric dentistry, sealant

Objective: The objective of this study was to analyze the clinicopathologic data of salivary gland tumors in Bangkok, Thailand. Method and Materials: Cases diagnosed with salivary gland tumors were retrieved from a dental school and a medical school in Bangkok, Thailand. Clinicopathologic data were recorded and analyzed with respect to gender, age, site, and histologic type. Results: Of the 411,851 cases, 1,047 salivary gland tumors (0.2%) were found. The male to female ratio was 1:1.2. The age of patients ranged from 1 to 88 years with an average age of 47.1 years. 721 cases were benign tumors (68.8%) while 326 cases (31.2%) were malignant tumors. The parotid gland was the most common site (62.7%), followed by the submandibular gland (18.8%), and the intraoral minor salivary glands (18.0%). Among the intraoral minor salivary glands, palate was the most common site (49.2%). The most common benign and malignant tumors were pleomorphic adenoma and mucoepidermoid carcinoma. Conclusions: Salivary gland tumors are rare. Compared with Western countries, the prevalence of polymorphous low-grade adenocarcinoma (PLGA) in Southeast Asia is low. Data from this study may be helpful for dentists in making differential diagnoses. Keywords: benign tumors, intraoral minor salivary glands, major salivary glands, malignant tumors, prevalence, salivary gland tumors

This case report presents the clinical and histologic evaluation of the application of a cross-linked collagen membrane and a new highly purified bovine xenograft with type 1 collagen fiber preservation (Laddec) in mandibular horizontal ridge augmentation on a 50-year-old woman. Significant bone volume was achieved to restore severe bone defect in order to place two implants. Histomorphometric analysis of a bone core at the augmented site, at 6 months, showed new bone formation with bone substitute particles integrated to new viable bone. Keywords: bovine bone-derived biomaterial, cross-linked collagen membrane, horizontal bone augmentation

Objective: To determine the detection rate of mandibular condyle pseudocyst in both digital panoramic radiographs and film-based panoramic radiographs. Method and Materials: All film-based and digital panoramic radiographs of patients treated at our institute during a 4-month period were analyzed by two experienced practitioners. Diagnosis of a condylar pseudocyst was based on the following criteria: appearance of cyst-like radiolucency, partially or completely circumscribed by radiopaque border, located at the anterior aspect of mandibular condyle. Results: 825 radiographs (415 film-based, 410 digital) were included in the study. In 342 (41.5%) radiographs at least one condylar pseudocyst was observed, with no differences between radiograph type, 173 (42.2%) in digital and 169 (40.7%) in film-based radiographs (P = .36). Condylar pseudocyst detection rate was positively associated with older age (P .001), whereas gender had no influence (P = .93). Conclusion: An equally high detection rate of condylar pseudocyst was found in digital and film-based panoramic radiographs. Keywords: cyst, digital radiology, mandible, panoramic radiograph, temporomandibular joint