Photobiomodulation-Based Synergic Effects of Pt-Coated TiO2 Nanotubes and 850 nm Near-Infrared Irradiation on the Osseointegration Enhancement: In Vitro and In Vivo Evaluation.

Photobiomodulation (PBM) therapy is known to have the potential to improve bone regeneration after implant surgery. However, the combinatory effect of the nanotextured implant and PBM therapy on osseointegration has not yet been proved. This study evaluated the photobiomodulation-based synergistic effects of Pt-coated titania nanotubes (Pt-TiO2 NT) and 850 nm near-infrared (NIR) light on osteogenic performance in vitro and in vivo. The FE-SEM and the diffuse UV-Vis-NIR spectrophotometer were used to perform the surface characterization. The live-dead, MTT, ALP, and AR assays were tested to perform in vitro tests. The removal torque testing, the 3D-micro CT, and the histological analysis were used to conduct in vivo tests. The live-dead and MTT assay resulted in Pt-TiO2 NTs being biocompatible. The ALP activity and AR assays demonstrated that the combination of Pt-TiO2 NT and NIR irradiation significantly enhanced osteogenic functionality (p < 0.05). The results of in vivo test, employing the removal torque testing, the 3D-micro CT, and histological analysis, showed overall improved outcomes; however, no significant difference was observed between the control and experimental groups (p > 0.05). Therefore, we confirmed the possibility of the combination of Pt-TiO2 NT and NIR light as a promising technology for implant surgery in dentistry.

Evaluation of the machinability and machining accuracy of polymer-based CAD/CAM blocks using merlon fracture test model.

The aims of this study were to estimate the machinability and machining accuracy of polymer-based CAM blocks using the merlon fracture test model specified in ISO 18675: 2022. Three hybrid disc blanks (MazicDuro, HC Disk, and Enamic) and three polymethyl methacrylate (PMMA) disc blanks (PMMA Disk, PMMA Block, and MazicTemp Hybrid) were tested in this study. The machinability was evaluated by assigning scores according to the fracture range of merlons with areas divided by ten vertical planes. The machining accuracy was evaluated by superimposing methods via CAD reference data and CAD specimen data. Within the limits of this study, a thickness of 0.3 mm is recommended for the clinical application of polymer-based CAD/CAM blocks in dental restorations that require superior machinability and accuracy. In addition, the machinability and machining accuracy tests of polymer-based CAM blocks are expected to provide guidelines for preparing accurate dental restorations.

Sinus lifts in the presence of pseudoantral and mucous retention cysts.

Objectives: Mucous retention cysts and pseudoantral cysts are mainly located within the floor of the maxillary sinus. Most of these maxillary cysts are asymptomatic and often only require observation. However, the presence of these benign maxillary cysts may create problems when maxillary sinus all types of implants are needed. Various treatment methods have been introduced. The selected treatment option depends on the type, size, and location of the cyst and its symptoms. Patients and. Methods: The case reports of four patients with maxillary cysts were reviewed retrospectively. These patients received a sinus lift between January 2016 and October 2021 at the Wonkwang University Dental Hospital. Results: To reduce unnecessary operations and the duration of treatment, a conservative treatment method is required. A sinus lift in the presence of maxillary cyst will not typically cause sinus problems if the lifted sinus membrane does not interfere with ventilation of the maxillary sinus. Conclusion: When proper treatment is provided, sinus perforation during a sinus lift performed in the presence of maxillary cyst and contamination of bone graft materials by cystic fluid does not necessarily result in adverse outcomes.

A Comparative Study of Additive and Subtractive Manufacturing Techniques for a Zirconia Dental Product: An Analysis of the Manufacturing Accuracy and the Bond Strength of Porcelain to Zirconia.

This study was aimed at preparing zirconia samples via additive manufacturing (AM) and subtractive manufacturing (SM) and testing the following aspects: (1) the manufacturing accuracy of the zirconia samples and (2) the bond strength of porcelain to zirconia to evaluate the applicability of the zirconia fabricated by AM in dental clinics. We used three milling machines for SM (AR, K5, and UP) and a 3D printer for AM (AO). The manufacturing accuracy of the zirconia specimen in the internal and marginal areas was evaluated by superimposing techniques to calculate the root mean square (RMS) values. The bond strengths of porcelain to zirconia prepared via SM and AM were measured using a universal testing machine. The internal and marginal RMS values of the zirconia prepared by AM (AO) were within the range of those of the zirconia prepared by SM (AR, K5, and UP). Moreover, the bond strength value of the zirconia prepared by AM (35.12 ± 4.09 MPa) was significantly higher than that of the zirconia prepared by SM (30.26 ± 5.20 MPa). Therefore, AM technology has significant potential for applications in dentistry.

Post-extraction pain in the adjacent tooth after surgical extraction of the mandibular third molar.

BACKGROUND: After tooth extraction, pain due to dry socket and pain in the adjacent tooth are common. The aim of this study was to retrospectively analyze pain in the adjacent tooth after surgical extraction of the mandibular third molar. METHODS: Postoperative pain due to dry socket, pain in the adjacent tooth, and pain from other causes were present. Group A included patents with dry socket alone; group B included patients with pain in the adjacent tooth alone; and group C included patients with both. The duration of symptoms was recorded. In addition, the prognosis of pain was divided into the complete improvement, improvement, maintenance, deterioration, and complete deterioration groups. RESULTS: A total of 312 mandibular third molars were extracted from 13, 60, and 10 patients in groups A, B, and C, respectively. The mean duration of symptoms was 5 days in group A and B and 15.2 days in group C. There were statistically significant differences in the duration of symptoms between groups A and C and groups B and C. CONCLUSION: Pain in the adjacent tooth after third molar extraction can be caused by inflammatory reactions and pressure on this tooth. The pain caused by pressure on the periodontal ligament and alveolar bone results from the cytokines released by osteoclasts, which are responsible for bone destruction. However, pain from periodontal ligament damage caused by excessive pressure may be misunderstood as pulpal pain. Unconscious parafunctional habits, such as clenching and bruxism, could also be associated with post-extraction pain.

Case series of cleidocranial dysplasia: Radiographic follow-up study of delayed eruption of impacted permanent teeth.

This report describes 3 cases of cleidocranial dysplasia (CCD) and presents relevant findings on long-term follow-up radiographic images of impacted permanent teeth with delayed eruption. Radiographic images of 3 CCD patients were reviewed retrospectively. These images were mainly composed of panoramic and skull radiographs, and the follow-up periods were 3, 13, and 13 years, respectively. The distinct features revealed by the images were described, and the eruption state of impacted permanent teeth was evaluated. The features common to the 3 cases were multiple supernumerary teeth, the presence of Wormian bone, underdevelopment of the maxilla and the maxillary sinus, and clavicular hypoplasia. The eruption of impacted permanent teeth was not observed without proper dental treatment in adult CCD cases, even after long time periods had elapsed. When proper orthodontic force was applied, tooth movement was observed in a manner not significantly different from the general population.

Non-Invasive Photodynamic Therapy against -Periodontitis-causing Bacteria.

Periodontitis is initiated by causative bacteria in the gingival sulcus. However, as the lesion is often deep and out of circulation system and biofilm is frequently formed on the bacteria cluster, use of antibacterial agents has been limited and the invasive method such as curettage is thought as an only treatment. Here we designed non-invasive photodynamic therapy (PDT), with the ointment which leads a photosensitizer deliverable into gingival sulcus. We assessed whether 650 nm light-emitting-diode (LED) penetrates the 3-mm soft tissue and effectively activates a photosensitizer toluidine-blue-O (TBO) through the thickness to remove Porphyromonas gingivalis and Fusobacterium nucleatum species. The oral ointment formulation was optimized to efficiently deliver the photosensitizer into gingival sulcus and its efficacy of PDT was evaluated in in vitro and in vivo models. Four weeks of TBO-formulation mediated-PDT treatment significantly attenuated periodontitis-induced alveolar bone loss and inflammatory cytokines production in rats. These results confirm that a 650 nm LED indeed penetrates the gingiva and activates our TBO formulation which is sufficiently delivered to, and retained within, the gingival sulcus; thus, it effectively kills the bacteria that reside around the gingival sulcus. Collectively, TBO-mediated PDT using LED irradiation has potential as a safe adjunctive procedure for periodontitis treatment.

Protrusive maxillomandibular fixation for intracapsular condylar fracture: a report of two cases.

Clinical limitations following closed reduction of an intracapsular condylar fracture include a decrease in maximum mouth opening, reduced range of mandibular movements such as protrusion/lateral excursion, and reduced occlusal stability. Anteromedial and inferior displacement of the medial condyle fragment by traction of the lateral pterygoid muscle can induce bone overgrowth due to distraction osteogenesis between the medial and lateral condylar fragments, causing structural changes in the condyle. In addition, when conventional maxillomandibular fixation (MMF) is performed, persistent interdental contact sustains masticatory muscle hyperactivity, leading to a decreased vertical dimension and premature contact of the posterior teeth. To resolve the functional problems of conventional closed reduction, we designed a novel method for closed reduction through protrusive MMF for two weeks. Two patients diagnosed with intracapsular condylar fracture had favorable occlusion after protrusive MMF without premature contact of the posterior teeth. This particular method has two main advantages. First, in the protrusive position, the lateral condylar fragment is moved in the anterior-inferior direction closer to the medial fragment, minimizing bone formation between the two fragments and preventing structural changes. Second, in the protrusive position, posterior disclusion occurs, preventing masticatory muscle hyperactivity and the subsequent gradual decrease in ramus height.

Prevalence of pathologies related to impacted mandibular third molars.

OBJECTIVE: Prevalence of cysts and tumors related to impacted third molars has been considered important because the risk justifies prophylactic extraction. This retrospective study aimed to evaluate the prevalence of cysts or tumors associated with impacted mandibular third molars (IMTMs) according to patients' age and gender. METHODS: Over the period from August 2006 to August 2011, 20,802 third molars from 17,535 patients were removed. Among these, IMTMs without cysts nor tumors were classified as non-pathology group, and IMTMs with cysts and tumors were classified into pathology group. The prevalence of IMTMs and associated cysts or tumors was analyzed in patient groups stratified by age and gender. The pathology group patients were also classified according to histopathological findings and the corresponding age groups. RESULTS: Radiographic signs of disease were detected for 176 lesions (0.846 %) in 165 patients. Of these, 135 (76.4 %) lesions were diagnosed as dentigerous cysts, 31 (17.6 %) as keratocysticodontogenic tumors, and 10 (5.7 %) as ameloblastomas. The prevalence of cysts or tumors tended to increase after 50 years of age, such as 7.27 % in 6th decades, 18.60 % in 7th decades, and 11.53 % in 8th decades, with a male predominance in older patients. CONCLUSIONS: IMTMs in old age patients more than 50 years old has high possibilities of developing cyst or tumors especially in male patients. However, these results should not be used as the only evidence for justifying prophylactic extraction, and further studies should investigate the survival rate of IMTMs without any pathologic in older populations.

Changes of lip morphology following mandibular setback surgery using 3D cone-beam computed tomography images.

BACKGROUND: The aims of this study are to evaluate the lip morphology and change of lip commissure after mandibular setback surgery (MSS) for class III patients and analyze association between the amount of mandibular setback and change of lip morphology. METHODS: The samples consisted of 14 class III patients treated with MSS using bilateral sagittal split ramus osteotomy. Lateral cephalogram and cone-beam CT were taken before and about 6 months after MSS. Changes in landmarks and variables were measured with 3D software program Ondemand™. Paired and independent t tests were performed for statistical analysis. RESULTS: Landmarks in the mouth corner (cheilion, Ch) moved backward and downward (p < .005, p < .01). However, cheilion width was not statistically significantly changed. Landmark in labrale superius (Ls) was not altered significantly. Upper lip prominence angle (ChRt-Ls-ChLt °) became acute. Landmarks in stomion (Stm), labrale inferius (Li) moved backward (p < .005, p < .001). Lower lip prominence angle (ChRt-Li-ChLt °) became obtuse (p < .001). Height of the upper and lower lips was not altered significantly. Length of the upper lip vermilion was increased (p =< 0.01), and length of the lower lip vermilion was decreased (p < .05). Lip area on frontal view was not statistically significantly changed, but the upper lip area on lateral view was increased and change of the lower lip area decreased (p > .05, p < .005). On lateral view, upper lip prominent point (UP) moved downward and stomion moved backward and upward and the angle of Ls-UP-Stm (°) was decreased. Lower lip prominent point (LP) moved backward and downward, and the angle of Stm-LP-Li (°) was increased. Li moved backward. Finally, landmarks in the lower incisor tip (L1) moved backward and upward, but stomion moved downward. After surgery, lower incisor tip (L1) was positioned more superiorly than stomion (p < .05). There were significant associations between horizontal soft tissue and corresponding hard tissue. The posterior movement of L1 was related to statistically significantly about backward and downward movement of cheilion. CONCLUSIONS: The lip morphology of patients with dento-skeletal class III malocclusion shows a significant improvement after orthognathic surgery. Three-dimensional lip morphology changes in class III patients after MSS exhibited that cheilion moved backward and downward, upper lip projection angle became acute, lower lip projection angle became obtuse, change of upper lip area on lateral view was increased, change of lower lip area decreased, and morphology of lower lip was protruding. L1 was concerned with the lip tissue change in statistically significant way.

Diseases having an influence on inhibition of angiogenesis as risk factors of osteonecrosis of the jaw.

OBJECTIVES: The objective of this study was to retrospectively investigate the association of diseases having an influence on inhibition of angiogenesis such as hypertension, diabetes mellitus type II, hypercholesterolemia, and rheumatoid arthritis (RA) with the development of osteonecrosis of the jaws. MATERIALS AND METHODS: The 135 patients were allocated into 4 groups of bisphosphonate-related osteonecrosis of the jaw (BRONJ) group (1A); non-BRONJ group (1B); osteonecrosis of the jaw (ONJ) group (2A); and control group (2B), according to histologic results and use of bisphosphonate. This retrospective study was conducted with patients who were treated in one institute from 2012 to 2013. Fisher's exact test and logistic regression analysis were used to analyze the odds ratios of diseases having an influence on inhibition of angiogenesis for development of ONJ. RESULTS: The effects of diabetes and hypertension were not statistically significant on development of ONJ. When not considering bisphosphonate use, RA exhibited a high odds ratio of 3.23 (P=0.094), while hyperlipidemia showed an odds ratio of 2.10 (P=0.144) for development of ONJ. More than one disease that had an influence on inhibition of angiogenesis showed a statistically significant odds ratio of 2.54 (P=0.012) for development of ONJ. CONCLUSION: Patients without diseases having an influence on inhibition of angiogenesis were at less risk for developing ONJ.

Correlations between anatomic variations of maxillary sinus ostium and postoperative complication after sinus lifting.

OBJECTIVES: The maxillary sinus mucosa is reported to recover to preoperative sterility after sinus floor elevation. However, when drainage of maxillary sinus is impaired, recovery can be delayed and maxillary sinusitis can occur. Therefore, in this study, we investigated the correlations between anatomic variants that can interrupt the ostium of the maxillary sinus and incidence of complication after sinus lifting. MATERIALS AND METHODS: The subjects are 81 patients who underwent sinus lifting in Wonkwang University Dental Hospital (Iksan, Korea). Computed tomography (CT) images of the subjects were reviewed for presence of nasal septum deviation, anatomic variants of the middle turbinate, and Haller cells. Correlations between anatomic variations and occurrence of maxillary sinusitis were statistically analyzed. RESULTS: Patients with anatomic variants of ostio-meatal units, such as deviated nasal septum, concha bullosa or paradoxical curvature of the middle turbinate, or Haller cells, showed a higher rate of complication. However, only presence of Haller cell showed statistically significant. CONCLUSION: Before sinus lifting, CT images are recommended to detect anatomic variants of the ostio-meatal complex. If disadvantageous anatomic variants are detected, the use of nasal decongestants should be considered to reduce the risk of postoperative sinusitis.

Advantages of intraoral and transconjunctival approaches for posterior displacement of a fractured zygomaticomaxillary complex.

BACKGROUND: Fracture of the zygomaticomaxillary complex (ZMC) is one of the most common facial injuries. A previous study has performed 3D analyses of the parallel and rotational displacements that occur in a fractured ZMC. However, few studies have investigated adequate fixation methods according to these displacements. Here, we assessed whether specific approaches and fixation methods for displacement of ZMC fractures produce esthetic results. METHODS: Hospital records and pre- and post-surgical computed tomographic scans of patients treated for ZMC fractures at the Department of Oral and Maxillofacial Surgery, College of Dentistry, Wonkwang University, between January 2010 and December 2015, were selected. Data were analyzed according to the direction of displacement and post-reduction prognosis using a 3D software. RESULTS: With ZMC fractures, displacement in the posterior direction occurred most frequently, while displacement in the superior-inferior direction was rare. A reduction using a transconjunctival approach and an intraoral approach was statistically better than that using an intraoral approach, Gillies approach, and lateral canthotomy approach for a posterior displacement (P < 0.05). CONCLUSIONS: When posterior displacement of a fractured ZMC occurs, use of an intraoral approach and transconjunctival approach simultaneously is recommended for reducing and fixing the displaced fragment accurately.

The Effect of Covalently Immobilized FGF-2 on Biphasic Calcium Phosphate Bone Substitute on Enhanced Biological Compatibility and Activity.

The purpose of this research was to covalently graft fibroblast growth factor 2 (FGF-2) onto biphasic calcium phosphate (BCP) via a bifunctional cross-linker technique and to estimate the optimal dose of FGF-2 resulting in the best osteogenic differentiation of human mesenchymal stem cells (hMSCs). SEM observation revealed that the surface of the 100 ng FGF-2 coated BCP was completely covered with the nanoparticles expected to be from the silane coupling agent. XRD, FT-IR, and XPS analysis showed that silane treatment, bifunctional cross-linker coating, and FGF-2 covalent grafts were conducted successfully without deforming the crystalline structure of BCP. An MTT assay demonstrated that FGF-2 coated BCP had good biocompatibility, regardless of the concentration of FGF-2, after 24 or 48 h of incubation. An alkaline phosphatase (ALP) activity assay (14 days of incubation) and the ALP gene expression level of real-time PCR analysis (7 days of incubation) revealed that 50, 100, and 200 ng FGF-2 coated BCP induced the highest activities among all experimental groups and control group (P < 0.05). Thus, low concentrations of FGF-2 facilitated excellent osteogenesis and were effective at enhancing osteogenic potential. Also, the bifunctional cross-linker technique is expected to be a more feasible way to induce osteogenic differentiation while minimizing the risk of FGF-2 overdose.

Tuberculosis of the temporomandibular joint: a case of misdiagnosis.

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis, continues to be a major health problem worldwide. Primary TB infection is mostly pulmonary, but it may also occur in the lymph nodes, abdomen, skin, meninges, joints, and central nervous system. TB in the head and neck region usually occurs in the cervical lymph nodes, but is extremely rare in the temporomandibular joint (TMJ). This rarity increases the risk for not considering TB in the differential diagnosis of patients presenting with TMJ pain. This article describes an unusual case of a 53-year-old man with painful swelling in the right preauricular area accompanied by difficulty in mouth opening. After surgical exploration, histopathologic findings revealed TB in the TMJ. The findings of this case highlight the importance of considering TB in the differential diagnosis of TMJ pain, especially for patients from endemic areas, patients who have lived or visited those areas, or patients with a preauricular swelling in the TMJ area.

Glandular odontogenic cyst mimicking ameloblastoma in a 78-year-old female: A case report.

Glandular odontogenic cyst (GOC) is a rare, potentially aggressive jaw lesion. The common radiographic features include a well-defined radiolucency with distinct borders, presenting a uni- or multilocular appearance. A cystic lesion in the posterior mandible of a 78-year-old female was incidentally found. Radiographs showed a unilocular lesion with a scalloped margin, external root resorption of the adjacent tooth, and cortical perforation. This lesion had changed from a small ovoid shape to a more expanded lesion in a period of four years. The small lesion showed unilocularity with a smooth margin and a well-defined border, but the expanded lesion produced cortical perforation and a lobulated margin. The provisional diagnosis was an ameloblastoma, whereas the histopathological examination revealed a GOC. This was a quite rare case, given that this radiographic change was observed in the posterior mandible of an elderly female. This case showed that a GOC can grow even in people in their seventies, changing from the unilocular form to an expanded, lobulated lesion. Here, we report a case of GOC with characteristic radiographic features.

Modified mandibulotomy technique to reduce postoperative complications: 5-year results.

PURPOSE: To review the 5-year outcomes of our modified mandibulotomy technique. Retrospective review of a tertiary level oral cancer center. MATERIALS AND METHODS: During a 5-year period, 30 patients who had a uniform surgical technique consisting of a lower lip-splitting, modified stair-step osteotomy with thin saw blade and osteotome after plate-precontouring and combination fixation with monocortical osteosynthesis (miniplate) and bicortical osteosynthesis (maxiplate and bicortical screws), with at least 14 months postoperative follow-up, were selected and reviewed retrospectively. RESULTS: There were 8 women and 22 men with an average age of 56.5 years. All the patients involved malignancies were squamous cell carcinoma. The main primary sites of the those who underwent a mandibulotomy were the tonsil, the base of tongue, the oral tongue, the retromolar pad area, and others. Others included buccal cheek, floor of mouth, and soft palate. 23 patients received postoperative radiation therapy, and among whom 8 patients also received chemotherapy. Total four (13%) mandibulotomy-related complications occurred, only two (6.7%) requiring additional operation under general anesthesia. CONCLUSION: Our modified mandibulotomy meets the criteria for an ideal mandibulotomy technique relatively well because it requires no intermaxillary fixation, can precise preserve the occlusion in a precise way, allows early function, requires no secondary procedures, and has few complications.

Complications in endoscopic-assisted open reduction and internal fixation of mandibular condyle fractures.

Endoscopic-assisted open reduction and internal fixation (EAORIF) of subcondylar fractures is minimally invasive, provides excellent visibility without a large incision, and reduces surgical scarring and the risk of facial nerve injury. This study evaluated the complications associated with EAORIF. Twenty-six patients underwent EAORIF for mandibular condyle fractures. The postoperative follow-up period was longer than 6 months. We analyzed associations between the complication incidence and the number of fixation plates, accompanying mandibular fractures, and age. Eighteen (69.2%) and 6 (23.1%) patients had temporary (<3 months after surgery) and long-term (>6 months after surgery) complications, respectively. Patients older than 30 years had complications more frequently than those younger than 30 years. Complication rates were similar for different numbers of fixation plates and among patients with and without accompanying mandibular fractures. EAORIF is a reliable technique for treating condylar fractures, regardless of patient age, number of fixation plates, or accompanying mandibular fractures. However, improvements are needed to reduce long-term complications.

Prognosis of gingival squamous cell carcinoma diagnosed after invasive procedures.

Gingival squamous cell carcinoma (SCC) has a relatively poor prognosis, because differential diagnoses of periodontitis and osteomyelitis are difficult to exclude. As such, gingival SCC is usually diagnosed late, following invasive procedures such as extraction or curettage. The purpose of this study was to classify gingival SCC patients into two groups according to the location of their primary lesion: dentate and edentulous, and to determine the appropriate treatment strategy by comparing clinical and histological features as well as treatment results. The medical records of 76 patients diagnosed with gingival SCC and treated at one institute from 1 January 1993 to 31 December 2007 were reviewed. The overall 5-year survival rate was 60.7%, and the mean survival was 98 months. Factors affecting survival included bone invasion of the primary lesion (p = 0.035), neck node metastasis (p = 0.001), and local recurrence (p = 0.000). The results suggest that more aggressive treatment, such as setting a broad surgical field and enforcing preventive neck dissection, can improve outcome, although they are associated with increased rate of cancer bone invasion and neck metastasis in patients diagnosed with cancer after receiving invasive procedures.

Anaphylactic shock caused by the epidurally-administered hyalurinidase.

Hyaluronidase is an enzyme that has temporary and reversible enzymatic effects on the matrix of connective tissue. When added to local anesthetics in pain treatments, it enhances their infiltration and dispersal into tissues. It is widely used in anesthesia for ocular, dental, and plastic surgery. Reports of drug hypersensitivity to hyaluronidase are rare and are usually confined to peribulbar or retrobulbar anesthesia during ophthalmic surgery. However, few reports exist on adverse drug reaction after epidural injection. We have observed two patients experiencing anaphylactic shock caused by hyaluronidase following epidural injection. Most of the patients with a hypersensitivity to hyaluronidase had one previous uneventful injection containing hyaluronidase, implying that sensitization had taken place. However, hypersensitivity occurring at the first administration is possible. A positive skin test can help establish the diagnosis. Although rare, the possibility of an allergic reaction to hyaluronidase should be considered even in patients with no known previous exposure.