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Concept: Dentistry


To identify where a consensus can be reached between veterinary experts in feline medicine on the core signs sufficient for pain (sufficient to indicate pain when they occur, but not necessarily present in all painful conditions) and necessary for pain (necessary in the presence of pain, but not always indicative of pain).

Concepts: Neuroscience, Neurology, Acupuncture, Dentistry, Suffering, Necessity


In April 2016, a Virginia dentist who had recently received a diagnosis of idiopathic pulmonary fibrosis (IPF) and was undergoing treatment at a specialty clinic at a Virginia tertiary care center contacted CDC to report concerns that IPF had been diagnosed in multiple Virginia dentists who had sought treatment at the same specialty clinic. IPF is a chronic, progressive lung disease of unknown cause and associated with a poor prognosis (1). Although IPF has been associated with certain occupations (2), no published data exist regarding IPF in dentists. The medical records for all 894 patients treated for IPF at the Virginia tertiary care center during September 1996-June 2017 were reviewed for evidence that the patient had worked as a dentist, dental hygienist, or dental technician; among these patients, eight (0.9%) were identified as dentists and one (0.1%) as a dental technician, and each had sought treatment during 2000-2015. Seven of these nine patients had died. A questionnaire was administered to one of the living patients, who reported polishing dental appliances and preparing amalgams and impressions without respiratory protection. Substances used during these tasks contained silica, polyvinyl siloxane, alginate, and other compounds with known or potential respiratory toxicity. Although no clear etiologies for this cluster exist, occupational exposures possibly contributed. This cluster of IPF cases reinforces the need to understand further the unique occupational exposures of dental personnel and the association between these exposures and the risk for developing IPF so that appropriate strategies can be developed for the prevention of potentially harmful exposures.

Concepts: Medicine, Pulmonology, Physician, Idiopathic pulmonary fibrosis, Dentistry, Dental technician, Dental assistant, Dental therapist


The aim was to determine if bracket prescription has any effect on the subjective outcome of pre-adjusted edgewise treatment as judged by professionals. This retrospective observational assessment study was undertaken in the Orthodontic Department of the Charles Clifford Dental Hospital, Sheffield, UK. Forty sets of post-treatment study models from patients treated using a pre-adjusted edgewise appliance (20 Roth and 20 MBT) were selected. The models were masked and shown in a random order to nine experienced orthodontic clinicians, who were asked to assess the quality of the outcome, using a pre-piloted questionnaire. The principal outcome measure was the Incisor and Canine Aesthetic Torque and Tip (ICATT) score for each of the 40 post-treatment models carried out by the nine judges. A two-way analysis of variance was undertaken with the dependent variable, total ICATT score and independent variables, Bracket prescription (Roth or MBT) and Assessor. There were statistically significant differences between the subjective assessments of the nine judges (P<0.001), but there was no statistically significant difference between the two bracket prescriptions (P = 0.900). The best agreement between a clinician's judgment of prescription used and the actual prescription was fair (kappa statistic 0.25; CI -0.05 to 0.55). The ability to determine which bracket prescription was used was no better than chance for the majority of clinicians. Bracket prescription had no effect on the subjective aesthetic judgments of post-treatment study models made by nine experienced orthodontists.

Concepts: Statistics, Hospital, Evaluation, Statistical significance, Assessment, Analysis of variance, Dentistry, Judgment


BACKGROUND: There are scarce evidences that evaluated the impact of periodontal disease on oral health-related quality of life (OHRQoL) taking marginal gingival alterations into consideration. Thus, this study aimed to verify the association between OHRQoL and gingival enlargement and gingival bleeding in subjects under fixed orthodontic treatment (FOT). METHODS: 330 participants under FOT for at least 6 months were examined by a single, calibrated examiner for periodontal variables. Socio-economic background, body mass index, time with orthodontic appliances, dental aesthetic index and use of dental floss were assessed by oral interviews. OHRQoL was evaluated using the oral health impact profile (OHIP-14) questionnaire. The assessment of associations used unadjusted and adjusted Poisson regression models. RESULTS: Higher impacts on the OHIP-14 overall were observed in subjects who presented higher levels of anterior gingival enlargement (RR 2.83; 95% CI 2.60-3.09), were non-whites (RR 1.29; 95% CI 1.15-1.45), had household income lower than five national minimum wages (RR 1.85; 95% CI 1.30-2.61), presented body mass index > 25 (RR 1.14; 95% CI 1.01-1.29), andshowed a dental aesthetic index > 30 (RR 1.32; 95% CI 1.20-1.46) . CONCLUSIONS: Anterior gingival enlargement seems to influence the OHRQoL in subjects receiving orthodontic treatment.

Concepts: Regression analysis, Gingiva, Periodontitis, Periodontal disease, Dentistry, Oral hygiene, Minimum wage, Dental floss


Osteoradionecrosis is a delayed complication from radiation therapy which causes chronic pain, infection and constant deformity after necrosis. Most of the osteoradionecrosis occurs spontaneously or after the primary oncologic surgery, dental extraction or by trauma of prosthesis. The treatment of osteoradionecrosis relies on both conservative measures and surgical measures. The fibular osteocutaneous free flap has become more popular choice for reconstruction of maxillofacial defects as a treatment of osteoradionecrosis.

Concepts: Medicine, Surgery, Chemotherapy, Radiation therapy, Dentistry, Oral and maxillofacial surgery, Toothache, Microsurgery


Methoxyflurane was developed as an anaesthetic agent and introduced into clinical practice in 1960. It soon became evident that it possessed analgesic properties that other drugs did not. Due to toxicity concerns, it lost favour in general anaesthesia and had been largely abandoned by the late 1970’s. The manufacturer withdrew it in 1999, and the Food and Drug Administration in the United States did not renew its license in 2005. It has also been withdrawn by the European Union. However, it continues to be used in Australasia, primarily as an inhaled self-administered analgesic by emergency services immediately following trauma. It has become attractive for use in dental practice, likely due to its effectiveness as an analgesic and its additional sedative qualities. Its acceptance is controversial as its use in dentistry is largely elective. Despite its good safety record in analgesic doses, adverse reactions have been recorded. Practitioners should be well aware of risks associated with its use before considering administration, and carefully assess whether or not there are equally good alternative options that do not the carry the same risks. Methoxyflurane is reviewed below with an emphasis on its use in dental practice. This article is protected by copyright. All rights reserved.

Concepts: Clinical trial, European Union, United States, Anesthesia, Dentistry, All rights reserved, Copyright, Legal terms


Subjects susceptible to chronic periodontitis (CP) show a high risk for the development of peiimplantitis (PI). Both diseases are multifactorial, presenting similarities in their pathophysiology and polygenic profile. MMP-13 (matrix metalloproteinases 13/ collagenase 3) is a collagenolytic enzyme, which expression is induced by TGF beta 3 (transforming growth factor type 3) in human gingival fibroblasts and inhibited by TIMP-2 (tissue inhibitor of metalloproteinase type 2). The aim of this study was to investigate the occurrence of peiimplantitis (PI) in subjects with history of chronic periodontitis (CP) and polymorphisms frequency in MMP13, TIMP2 and TGFB3 genes. One hundred and sixty-three volunteers received dental implant placement were submitted to oral and radiographic examination in order to identify past history of CP or presence of PI. Volunteers were divided into 4 groups: Control (without PI and CP, n=72), CP (with CP and without PI, n=28), PI (with PI and without CP, n=28) and diseased (with CP and PI, n=35). The chi-square test correlated genotypes in specific regions of MMP13 (rs2252070), TIMP2 (rs7501477) and TGFB3 (rs2268626) genes, considering the interaction between CP and PI. The results showed that volunteers with CP had 3.2 times more susceptibility to develop PI (p=0.0004) compared to those without CP. No significant association was observed in MMP13, TIMP2 and TGFB3 genes with CP or PI. CP is a risk factor to develop PI, however, there is no association of both diseases with polymorphisms in the MMP13, TIMP2 and TGFB3 genes.

Concepts: Gene, Genetics, Dental implant, Dentistry, Tissue inhibitor of metalloproteinases, Transforming growth factor, TGF beta, TGF beta 3


Dementia may be associated with discontinuation of regular dental checkups, which in turn results in poorer oral health.

Concepts: Health care, Dental implant, Dentistry


Oral cancers are attributed to a number of causal agents including tobacco, alcohol, human papillomavirus (HPV), and areca (betel) nut. Although betel nut chewing has been established as an independent cause of oral cancer, the mechanisms of carcinogenesis are poorly understood. An investigation was undertaken to evaluate the influence of betel nut chewing on the oral microbiome and oral premalignant lesions. Study participants were recruited from a dental clinic in Guam. Structured interviews and oral examinations were performed. Oral swabbing and saliva samples were evaluated by 454 pyrosequencing of the V3- V5 region of the 16S rRNA bacterial gene and genotyped for HPV. One hundred twenty-two adults were enrolled including 64 current betel nut chewers, 37 former chewers, and 21 with no history of betel nut use. Oral premalignant lesions, including leukoplakia and submucous fibrosis, were observed in 10 chewers. Within-sample bacterial diversity was significantly lower in long-term (‚Č•10 years) chewers vs. never chewers and in current chewers with oral lesions vs. individuals without lesions. Between-sample bacterial diversity based on Unifrac distances significantly differed by chewing status and oral lesion status. Current chewers had significantly elevated levels of Streptococcus infantis and higher and lower levels of distinct taxa of the Actinomyces and Streptococcus genera. Long-term chewers had reduced levels of Parascardovia and Streptococcus. Chewers with oral lesions had significantly elevated levels of Oribacterium, Actinomyces, and Streptococcus, including Streptococcus anginosus. In multivariate analyses, controlling for smoking, oral HPV, S.anginosus, and S. infantis levels, current betel nut chewing remained the only predictor of oral premalignant lesions. Our study provides evidence that betel nut chewing alters the oral bacterial microbiome including that of chewers who develop oral premalignant lesions. Nonetheless, whether microbial changes are involved in betel nut-induced oral carcinogenesis is only speculative. Further research is needed to discern the clinical significance of an altered oral microbiome and the mechanisms of oral cancer development in betel nut chewers.

Concepts: Cancer, Bacteria, Human papillomavirus, Ribosomal RNA, Head and neck cancer, Dentistry, Areca nut, Betel


To develop a questionnaire based on patients' verbal descriptors, to measure the painful symptoms of endometriosis METHODS: We performed a two-round modified DELPHI procedure mixing endometriosis patients and physicians to select a set of statements to describe the painful symptoms of endometriosis. Each panelist rated each statement based on diagnosis validity and clarity. The clinicians were experts in endometriosis management selected from various geographic regions in France. Patients were women with surgically confirmed endometriosis who volunteered from a patient association and from the recruitment of the participating physicians. The first round questions were derived from words and phrases in narratives of pain by endometriosis patients.

Concepts: Medical terms, Patient, Hospital, Greek loanwords, Physician, Doctor-patient relationship, Sentence, Dentistry