Efficacy assessment of laser Doppler imager in diagnosing the pulp vitality after dental trauma.

Background/purpose: This is the first paper evaluating the efficacy of laser Doppler imager in diagnosis of pulpal vitality. The purpose of this study was to evaluate and compare the diagnostic benefits of laser Doppler imaging and electric pulp test (EPT) in dental trauma. Materials and methods: Seven patients were selected for pulp vitality evaluation in Kaohsiung Medical University Hospital between 2018 and 2019. EPT and laser Doppler imager evaluation were performed for patients with traumatic injury to teeth. Statistical methods included the Kappa consistency test and the chi-square test. In addition, the receiver operating characteristic (ROC) curve, and the area under the curve (AUC) were used. Results: There was a significant difference in Doppler flow values between the severe trauma group and the mild trauma group, regardless of patient self-reported symptoms (P = 0.043) or physicians' diagnostic classification (P = 0.018). For an EPT instrument, the Kappa coefficient was 0.67 and 1-year pulpal status findings were highly consistent (P < 0.001). Using a Doppler instrument, the Kappa coefficient was 0.85. According to the ROC curve, the AUC for EPT was 0.94, the AUC for Doppler was 1, and the optimal cut-off value was 31.55, indicating that both were superior diagnostic tools. Conclusion: Both laser Doppler imager and EPT can be used as tools for diagnosing traumatic pulp necrosis. Doppler imaging instruments allow for a more timely and accurate assessment of pulp vitality in dental trauma. In the future, ongoing research and related training are necessary for interpretation of Doppler data.

Sprouty 4 expression in human oral squamous cell carcinogenesis.

Background/purpose: Reviewing literature, sprouty 4 (SPRY4) has not been studied in human oral squamous cell carcinomas (OSCCs). The study aimed to examine SPRY4 expression in human oral squamous cell carcinogenesis. Materials and methods: A total of 95 OSCCs, 10 OPMDs with malignant transformation (MT), 17 OPMDs without MT, and six normal oral mucosa (NOM) samples were recruited for immunohistochemical staining; three OSCC tissues with normal tissue counterpart NOM were employed for Western blotting. Three human oral cancer cell lines (OCCLs), an oral precancer cell line (dysplastic oral keratinocyte, DOK), and a primary culture of normal oral keratinocytes (HOK) were used for Western blotting; OCCLs and HOK were employed for real-time quantitative reverse transcription-polymerase chain reaction. OCCLs were evaluated in terms of proliferation, migration, and invasion assays. Results: SPRY4 protein expression was significantly increased in OSCCs compared with NOM. Protein and mRNA SPRY4 expression in OCCLs were significantly elevated compared with HOK. Significant increases in the degrees of proliferation, migration, and invasion were noted in OCCLs with SPRY4 siRNA transfection compared with those without transfection. SPRY4 protein level was increased in OPMD with MT compared to OPMD without MT. SPRY4 protein was significant increase in DOK in comparison with HOK. SPRY4 protein expression was significantly increased from NOM and OPMD without MT to OSCC. SPRY4 protein expression in OCCLs was significantly enhanced compared with DOK and HOK respectively. Conclusion: Our results indicate that SPRY4 expression is possibly involved in human oral squamous cell carcinogenesis.

Stimulation phosphatidylinositol 3-kinase/protein kinase B signaling by Porphyromonas gingivalis lipopolysacch aride mediates interleukin-6 and interleukin-8 mRNA/protein expression in pulpal inflammation.

BACKGROUND/PURPOSE: The signaling mechanisms for Porphyromonas gingivalis lipopolysaccharide (PgLPS)-induced inflammation in human dental pulp cells are not fully clarified. This in vitro study aimed to evaluate the involvement of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in PgLPS-induced pulpal inflammation. METHODS: Human dental pulp cells (HDPCs) were challenged with PgLPS with or without pretreatment and coincubation with a PI3K/Akt inhibitor (LY294002). The gene or protein levels of PI3K, Akt, interleukin (IL)-6, IL-8, alkaline phosphatase (ALP), osteocalcin and osteonectin were analyzed by reverse transcription polymerase chain reaction (PCR), real-time PCR, western blotting, and immunofluorescent staining. In addition, an enzyme-linked immunosorbent assay was used to analyze IL-6 and IL-8 levels in culture medium. RESULTS: In response to 5 µg/ml PgLPS, IL-6, IL-8, and PI3K, but not Akt mRNA expression of HDPCs, was upregulated. IL-6, IL-8, PI3K, and p-Akt protein levels were stimulated by 10-50 µg/ml of PgLPS in HDPCs. PgLPS also induced IL-6 and IL-8 secretion at concentrations higher than 5 µg/ml. Pretreatment and co-incubation by LY294002 attenuated PgLPS-induced IL-6 and IL-8 mRNA expression in HDPCs. The mRNA expression of ALP, but not osteocalcin and osteonectin, was inhibited by higher concentrations of PgLPS in HDPCs. CONCLUSION: P. gingivalis contributes to pulpal inflammation in HDPCs by dysregulating PI3K/Akt signaling pathway to stimulate IL-6 and IL-8 mRNA/protein expression and secretion. These results are useful for understanding the pulpal inflammation and possible biomarkers of inflamed pulp diagnosis and treatment.

Conservative pulp treatment for Oehlers type III dens invaginatus: A case report.

BACKGROUND: Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful approach, i.e., we should consider the shape and depth of the concave folding, the condition of the original pulp, and the growth stage of the root formation. CASE SUMMARY: A 9-year-old girl complained of severe pain of the right maxillary incisor (tooth 12) when chewing for two weeks. Following clinical and radiographic examinations, Oehlers type III DI of tooth 12, with an immature open apical foramen and a symptomatic periapical pathosis, was diagnosed. Cone-beam computed tomography verified the specific spatial and stereoscopic data regarding the communication between the main root canal and pseudo root canal of the involved tooth. After removing the source of infection, a mineral trioxide aggregate was selected to fill and seal the pseudo root canal; additionally, pulp capping of the main canal was performed through the interconnections between the root canals in the middle segment to preserve pulp vitality and enable continual root formation and eventual root apex closure. CONCLUSION: We propose to conduct main root canal pulp capping for DI with communication between the main and pseudo root canals.

Clinicopathological analysis of 232 radicular cysts of the jawbone in a population of southern Taiwanese patients.

This retrospective study aimed to evaluate the clinicopathological features of 232 cases of radicular cyst (January 2001-December 2016) submitted for histopathological examination to Department of Oral Pathology by endodontists in our institution. Demographic data including age, gender, affected site, involved tooth, and histopathological features, were reviewed. The study population comprised 133 females (57.3%) and 99 males (42.7%), with a mean age of 40.5 years and an age range of 13-78 years. Two-hundred and one cysts occurred in the maxilla (86.7%) and 31 in the mandible (13.3%). Most cases involved the anterior teeth of the maxilla (67.2%). The most frequently-involved tooth was the maxillary lateral incisor (50.5%). In most cases (228 cases; 98.3%), the cyst was lined with nonkeratinized stratified squamous epithelium, with two cases containing epithelial lining of the mucoepidermoid epithelium (0.9%) and respiratory epithelium (0.9%), respectively. One case (0.4%) revealed epithelial dysplasia of the epithelial lining. Hyaline body was seen in two cases (0.9%), and Rushton body was noted in seven cases (3.0%). Odontogenic epithelial rest was noted in one case (0.4%). Cholesterol clefts (54 cases; 23.3%), foamy histiocytes (72 cases; 31.0%), hemosiderins (57 cases; 24.6%), dystrophic calcifications (94 cases; 40.5%), foreign bodies (44 cases; 19.0%), and bacterial colonies (22 cases; 9.5%) were also observed. Fifty-three cases (22.8%) showed a mixed acute and chronic inflammatory infiltrate, whereas chronic inflammatory infiltrate only was noted in 179 cases (77.2%). In summary, the current findings provide a valuable source for clinicopathological reference concerning radicular cysts of the jawbone.

Retrospective analysis of nonendodontic periapical lesions misdiagnosed as endodontic apical periodontitis lesions in a population of Taiwanese patients.

OBJECTIVE: We aimed to evaluate nonendodontic periapical lesions clinically misdiagnosed as endodontic periapical pathoses in a population of Taiwanese patients. MATERIALS AND METHODS: Cases (2000-2014) of histopathological diagnoses of nonendodontic periapical lesions were retrieved from all cases with a clinical diagnosis of radicular cyst, apical granuloma, or apical periodontitis in the institution. These cases were regarded as misdiagnosed nonendodontic periapical lesions, of which the types and frequencies, in addition to the demographic data, were determined. RESULTS: Four thousand and four specimens were clinically diagnosed as endodontically associated pathoses, of which 118 cases (2.95%) received a histopathological diagnosis of a nonendodontic pathologic entity, the most frequent lesion being keratocystic odontogenic tumor (KCOT, n = 38, 32.20%), followed by fibro-osseous lesion (n = 18, 15.25%), and dentigerous cyst (n = 13, 11.02%). Nine malignant lesions in the periapical area [squamous cell carcinoma (n = 7, 5.93%), adenoid cystic carcinoma (n = 1, 0.85%), and Langerhans cell histiocytosis (n = 1, 0.85%)] were also noted. CONCLUSIONS: A wide variety of histopathological diagnoses, including benign odontogenic and non-odontogenic cystic and tumorous lesions and infectious diseases, as well as malignant lesions, was noted in these 118 cases of nonendodontic periapical lesions. Squamous cell carcinoma was the most predominant malignancy of nonendodontic periapical lesions misdiagnosed as apical periodontitis lesions from imaging examination overlooking the clinical findings. CLINICAL RELEVANCE: The current data form a useful basis for clinicopathological investigation and educational teaching regarding nonendodontic periapical lesions misdiagnosed as endodontic apical periodontitis lesions.

Regulation of vascular cell adhesion molecule-1 in dental pulp cells by interleukin-1ß: the role of prostanoids.

INTRODUCTION: Vascular cell adhesion molecule (VCAM-1) plays a critical role in the inflammatory processes by stimulating the recruitment, extravasation, and migration of leukocytes. Its expression and regulation in the dental pulp is not well elucidated. METHODS: Primary dental pulp cells were exposed to prostaglandin E(2) (PGE(2)), prostaglandin F(2α) (PGF(2α)), or interleukin 1ß (IL-1ß) with/without aspirin. VCAM-1 messenger RNA expression was analyzed by reverse transcriptase-polymerase chain reaction. Soluble VCAM-1 (sVCAM-1) in the culture medium was determined by enzyme-linked immunosorbent assay, and the number of viable cells was estimated by (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS: IL-1ß induced VCAM-1 gene expression of pulp cells. IL-1ß also stimulated sVCAM-1 production. The IL-1ß-induced sVCAM-1 production was not inhibited but rather enhanced by aspirin, a cyclooxygenase (COX) inhibitor. PGE(2) and PGF(2α) decreased the VCAM-1 expression and sVCAM-1 production of pulp cells. U0126 (1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio]butadiene), a mitogen-activated protein kinase kinase (MEK) inhibitor, attenuated IL-1ß-induced sVCAM-1 production. However, no marked cytotoxicity was noted in these experimental conditions as analyzed by MTT assay. CONCLUSIONS: IL-1ß may be involved in the pulpal inflammatory processes via stimulation of VCAM-1 expression and sVCAM-1 production. This event is not mediated by COX activation and prostanoid production but is associated with MEK signaling. PGE(2) and PGF(2α) may potentially regulate inflammatory processes by the inhibition of VCAM-1.

Long-term sequential receptor activator of NF-κB ligand (RANKL) and osteoprotegrin (OPG) expression in lipopolysaccharide-induced rat periapical lesions.

BACKGROUND: Long-term sequential expression of receptor activator of NF-κB ligand (RANKL) and osteoprotegrin (OPG) in lipopolysaccharide (LPS)-induced rat periapical lesions has not been studied. MATERIALS: Seventy-two 4-week-old Wistar rats were divided into eight experimental groups and one control group (eight animals in each). METHODS: Lipopolysaccharide-induced periapical lesions were produced in rats by occlusal exposure of the pulp of their lower first molars in all experimental groups but not the control group. The extent of periapical destruction was measured by radiographic imaging. RANKL and OPG mRNA were measured in all tissue sections containing the periapical lesions as well as the control group every week from week 1 to week 8 by real-time quantitative reverse transcription polymerase chain reaction. RANKL and OPG protein were determined by immunohistochemistry. Osteoclasts were identified by enzyme histochemistry. RESULTS: The sequential changes in the mRNA and protein expression of RANKL and OPG were largely compatible with the occurrence of osteoclasts histologically and enzymes histochemically, as well as the mean areas of the periapical lesions radiographically during long-term observation of the LPS-induced rat periapical lesions. CONCLUSION: This study may be the first to demonstrate the long-term RANKL and OPG expression every week from week 1 to week 8 using LPS to produce periapical infection in a Wistar rat model. The long-term findings of high expressions of RANKL and OPG further extend the potential application of the Wistar rat model for future experimental trials using RANKL inhibitor to evaluate the treatment outcome for LPS-induced rat periapical lesions.

Caldwell-Luc procedure for retrieval of displaced root in the maxillary sinus.

OBJECTIVE: The aim of this study was to describe the standard diagnostic procedure and the application of the Caldwell-Luc approach for the retrieval of a displaced root from the maxillary sinus and to share our experience in treating this complication. STUDY DESIGN: Twenty-four patients with a fractured root accidentally displaced into the maxillary sinus were referred by general dentists to our department from 2005 to 2008. All were managed by a standardized diagnostic procedure and a Caldwell-Luc approach. We recorded the age of each patient, the gender, the tooth, the size of root fragment, the type of displacement the delay between displacement and retrieval, the length of operating time, and any complications. RESULTS: Over a 4-year period, we treated 24 patients, 14 being male and 10 female. Ages ranged from 14 to 55 years (average 26.4). The commonest tooth involved was the maxillary first molar; the length of the root fragments ranged from 3 to 7 mm. Seventeen of these roots were mobile and 7 fixed (4 being located between the sinus membrane and the bone and 3 immobilized by the sinus membrane. Twenty-three of the operations were completed in 30 minutes, and only 2 patients had a temporary complication of sinusitis. No infraorbital paresthesia occurred. CONCLUSIONS: The standardized diagnostic procedure and Caldwell-Luc approach for the retrieval of a displaced root form the maxillary sinus is a safe, simple, and fast method with minimal complications.

Occurrence of ameloblastoma in a patient with nasopharyngeal carcinoma after treatment by irradiation.

Ameloblastoma is the most common clinically significant epithelial odontogenic tumor, and is considered a benign but locally aggressive tumor of the craniofacial region. We present the case history of a 46-year-old male patient who had a nasopharyngeal carcinoma (NPC) treated by irradiation, which was complicated by the occurrence of an ameloblastoma. Following a review of the English language literature, this case history was identified as being the first report, to our knowledge, of the occurrence of ameloblastoma in a patient who had been irradiated for an NPC. This case report highlights the importance of regular dental care for a patient who had an NPC and was treated with radiation therapy.

Extensive subcutaneous emphysema after extraction of a mandibular third molar: a case report.

Surgical emphysema is an uncommon but potentially serious complication of third molar removal and other oral procedures. The purpose of this case report is to remind dentists of the risk of surgical emphysema. Surgical emphysema developed in a 32-year-old female after removal of a mandibular third molar using a high-speed dental hand-piece. Because of the extent of the swelling, the patient was admitted for observation. Because of progressive swelling, a submandibular surgical incision and drainage was performed, which led to rapid resolution. The diagnosis and differential diagnosis of surgical emphysema are discussed to draw dentists' attention to the management and prevention of this complication.

Immunohistochemical expression of RANKL, RANK, and OPG in human oral squamous cell carcinoma.

BACKGROUND: The mechanism of oral squamous cell carcinoma (SCC) invading jawbone remains controversial. Interactions between receptor activator of NF-kappaB (RANK) and its ligand (RANKL) are required for osteoclastogenesis. The binding of RANK and RANKL induces differentiation of osteoclasts, leading to bony destruction. Osteoprotegerin (OPG), a decoy receptor for RANKL, also binds to RANKL by competing with RANK, and this could protect against osseous destruction. MATERIALS AND METHODS: Immunoexpression of RANKL, RANK, and OPG in 25 cases of human buccal SCCs without bony invasion and 15 cases of gingival SCCs with mandibular bony invasion was investigated. Normal oral mucosa from five individuals without betel-quid chewing or cigarette smoking was used as a control. The scores are designated as percentage of positive staining x intensity of staining for each section. RESULTS: Strong cytoplasmic staining of RANKL proteins is detected in cancer cells of both buccal and gingival SCCs. The same protein is identified in cytoplasm of osteoclasts for all cases involving bony invasion. Strong cytoplasmic staining of RANKL is confined to basal layer for all normal mucosa. A similar staining pattern is noted for RANK protein in all buccal and gingival SCCs. An absence of staining of RANK protein is noted for all normal tissues. Weak to negative cytoplasmic stained OPG protein is present in all buccal and gingival SCCs, but is absent in all normal tissues. CONCLUSION: These findings suggest the potential value of the RANK/RANKL/OPG pathway as biomarkers in human oral SCCs.

Evaluation of the effect of laser tooth whitening.

PURPOSE: This study aimed to determine whether gender, age, and initial tooth hue impacted the effect of laser tooth whitening. MATERIALS AND METHODS: Ninety-one subjects were enrolled in a laser tooth whitening study at Kaohsiung Medical University. Sensitivity was evaluated by asking the patients about any tooth sensitivity they experienced after the whitening procedures were performed. The LaserSmile tooth whitener, containing 35% hydrogen peroxide, was applied to the tooth surfaces of both arches from the central incisor to the second premolar, and the LaserSmile Twilite diode laser was applied to the same maxillary and mandibular teeth. After removal of the whitening gel, shade matching was immediately performed with the ShadeEye NCC Dental Chroma Meter. Patients were classified into the following groups: tetracycline stain, gender, age, and initial tooth hue. Only 5 of the 91 individuals had tetracycline staining. RESULTS: The initial tooth shade and the amount of shade change showed no significant differences between female and male patients, but a significant difference was found between hue and age group. CONCLUSIONS: Teeth with hue A showed greater shade improvement than teeth with hue C and hue D. Whitening response was better in younger individuals, and gender was not a factor that affected the whitening response. Sensitivity is common during the whitening procedure but can be tolerated by the patients.

Peripheral odontogenic fibroma in a Taiwan chinese population: a retrospective analysis.

A retrospective analysis of 25 cases of peripheral odontogenic fibroma (World Health Organization type) (PODF [WHO-type]) in a Taiwan Chinese population was performed at a single institution. The clinical findings, which included a wide age distribution, a female preponderance and no racial predilection, were consistent with those of previous case series reports; however, a slight preference for location in the maxilla was found in the current case series. It is noteworthy that one particularly sizable lesion was identified in a 30-year-old Chinese female who presented with a swollen mass in the right mandible that had been present for about 2 years. Intraoral examination revealed an exophytic firm mass that measured 4.5 x 4 cm, located over the right mandibular edentulous ridge from the second premolar to the second molar area. Both panoramic radiography and computerized tomography revealed multiple radiopacities within the tumor. In conclusion, the analysis of clinical data in the current case series of PODFs (WHO-type) occurring in Taiwan Chinese mostly corroborates other reports; however, an unusually large mandible lesion was noted, indicative of the apparent size that such tumors can reach unless they are surgically removed at an early stage.

The combined occluding effects of fluoride-containing dentin desensitizer and Nd-Yag laser irradiation on human dentinal tubules: an in vitro study.

The purpose of the present study was to evaluate the combined occluding effects of fluoride-containing dentin desensitizer and neodymium:yttrium aluminum garnet (Nd-YAG) laser irradiation on human dentinal tubules. All six of the groups of dentin samples (A-F) included in this study received applications of fluoride-containing dentin desensitizer. Groups B, D, and F also received Nd-YAG laser irradiation. Groups A and B served as controls, to allow observations of the occluding effects on the dentinal tubules before and after Nd-YAG laser irradiation. Groups C and D were treated with 0.5 M vitamin C solution, whereas groups E and F underwent brushing with an electric toothbrush. Scanning electron microscopy (SEM) revealed that the fluoridated dentinal tubule-occluding agent (FDTOA) formed a fine crystalline deposit on the dentin surface. After soaking in 0.5 M vitamin C solution for 3 hours, the crystalline deposit of the FDTOA was completely dissolved. Furthermore, brushing of the teeth 3,600 times removed most of the occluding agent. When the application of FDTOA was combined with Nd-YAG laser irradiation, the dentin melted and then recrystallized. The occluding agent was thus 'burned into' the dentinal tubules, and could neither be dissolved by vitamin C solution nor removed by brushing. Therefore, we concluded that the FDTOA combined with Nd-YAG laser irradiation burns the occluding agent into the dentinal tubules, thereby resisting the effects of an acidic diet and brushing, and increasing the duration of the desensitizing effect.

Facial cellulitis arising from dens evaginatus: a case report.

Dens evaginatus is a developmental anomaly that produces a tubercle on the occlusal surface of a tooth. It is found most frequently in the mandibular premolars. The occlusal tubercle easily causes occlusal interferences. Attrition or fracture of the tubercle can lead to pulpitis, pulp necrosis, periapical pathosis, and periapical infection. This case report illustrates the treatment of facial cellulitis arising from dens evaginatus with open apex. Calcium hydroxide was used for the apexification procedure. One year after canal obturation, radiography revealed no apical pathosis and the apical seal was evident.