Dental root abnormalities in four children with PHACE syndrome.

PHACE(S) syndrome is a condition characterized by posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe. We present four children with PHACE(S) syndrome who have absence of or severe malformation of the roots of their permanent first molars (PFMs). Root abnormalities in the children's molars were bilateral and not restricted to the segments affected by cutaneous hemangioma. The reason for root abnormalities is unknown, but given the rarity of these findings in healthy children, it is likely an additional dental manifestation of PHACE syndrome. The absence of functional roots in the PFMs can result in significant consequences. Therefore, we recommend a panoramic dental radiograph during transitional dentition for children with PHACE syndrome to screen for dental root abnormalities.

Biochemical and spectroscopic characterization of purified Latex Clearing Protein (Lcp) from newly isolated rubber degrading Rhodococcus rhodochrous strain RPK1 reveals novel properties of Lcp.

BACKGROUND: Biodegradation of rubber (polyisoprene) is initiated by oxidative cleavage of the polyisoprene backbone and is performed either by an extracellular rubber oxygenase (RoxA) from Gram-negative rubber degrading bacteria or by a latex clearing protein (Lcp) secreted by Gram-positive rubber degrading bacteria. Only little is known on the biochemistry of polyisoprene cleavage by Lcp and on the types and functions of the involved cofactors. RESULTS: A rubber-degrading bacterium was isolated from the effluent of a rubber-processing factory and was taxonomically identified as a Rhodococcus rhodochrous species. A gene of R. rhodochrous RPK1 that coded for a polyisoprene-cleaving latex clearing protein (lcp Rr ) was identified, cloned, expressed in Escherichia coli and purified. Purified LcpRr had a specific activity of 3.1 U/mg at 30 °C and degraded poly(1,4-cis-isoprene) to a mixture of oligoisoprene molecules with terminal keto and aldehyde groups. The pH optimum of LcpRr was higher (pH 8) than for other rubber-cleaving enzymes (≈ pH 7). UVvis spectroscopic analysis of LcpRr revealed a cytochrome-specific absorption spectrum with an additional feature at long wavelengths that has not been observed for any other rubber-cleaving enzyme. The presence of one b-type haem in LcpRr as a co-factor was confirmed by (i) metal analysis, (ii) solvent extraction, (iii) bipyridyl assay and (iv) detection of haem-b specific m/z values via mass-spectrometry. CONCLUSIONS: Our data point to substantial differences in the active sites of Lcp proteins obtained from different rubber degrading bacteria.

Efficient production of polyhydroxyalkanoates (PHAs) from Pseudomonas mendocina PSU using a biodiesel liquid waste (BLW) as the sole carbon source.

Conditions for the optimal production of polyhydroxyalkanoate (PHA) by Pseudomonas mendocina PSU using a biodiesel liquid waste (BLW) were determined by response surface methodology. These were an initial carbon to nitrogen ratio (C/N) of 40 (mole/mole), an initial pH of 7.0, and a temperature of 35 °C. A biomass and PHA concentration of 3.65 g/L and about 2.6 g/L (77% DCW), respectively, were achieved in a growth associated process using 20 g/L glycerol in the BLW after 36 h of exponential growth. The PHA monomer compositions were 3HB (3-hydroxybutyrate), a short-chain-length-PHA, and the medium-chain-length-PHA e.g. 3-hydroxyoctanoate and 3-hydroxydecanoate. Both the phbC and phaC genes were characterized. The phbC enzyme had not been previously detected in a Pseudomonas mendocina species. A 2.15 g/L of an exopolysaccharide, alginate, was also produced with a similar composition to that of other Pseudomonas species.

Tooth enamel hypoplasia in PHACE syndrome.

Individuals with PHACE syndrome (posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe syndrome) have reported dental abnormalities to their healthcare providers and in online forums, but dental involvement has not been comprehensively studied. A study was conducted at the third PHACE Family Conference, held in Milwaukee, Wisconsin, in July 2012. A pediatric dentist examined subjects at enrollment. Eighteen subjects were enrolled. The median age was 4.2 years (range 9 mos-9 yrs; 14 girls, 4 boys). Eleven of 18 patients had intraoral hemangiomas and five of these (50%) had hypomature enamel hypoplasia. None of the seven patients without intraoral hemangiomas had enamel hypoplasia. No other dental abnormalities were seen. Enamel hypoplasia may be a feature of PHACE syndrome when an intraoral hemangioma is present. Enamel hypoplasia increases the risk of caries, and clinicians should refer children with PHACE syndrome to a pediatric dentist by 1 year of age.

Systematic review of laser and other light therapy for the management of oral mucositis in cancer patients.

BACKGROUND: The aim of this study was to review the available literature and define clinical practice guidelines for the use of laser and other light therapies for the prevention and treatment of oral mucositis. METHODS: A systematic review was conducted by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology. The body of evidence for each intervention, in each cancer treatment setting, was assigned an evidence level. Based on the evidence level, one of the following three guideline determinations was possible: recommendation, suggestion, and no guideline possible. RESULTS: A new recommendation was made for low-level laser (wavelength at 650 nm, power of 40 mW, and each square centimeter treated with the required time to a tissue energy dose of 2 J/cm(2) (2 s/point)) for the prevention of oral mucositis in adult patients receiving hematopoietic stem cell transplantation conditioned with high-dose chemotherapy, with or without total body irradiation. A new suggestion was made for low-level laser (wavelength around 632.8 nm) for the prevention of oral mucositis in patients undergoing radiotherapy, without concomitant chemotherapy, for head and neck cancer. No guideline was possible in other populations and for other light sources due to insufficient evidence. CONCLUSIONS: The increasing evidence in favor of low-level laser therapy allowed for the development of two new guidelines supporting this modality in the populations listed above. Evidence for other populations was also generally encouraging over a range of wavelengths and intensities. However, additional well-designed research is needed to evaluate the efficacy of laser and other light therapies in various cancer treatment settings.

Quantifying strategies to minimize aerosol dispersion in dental clinics.

Many dental procedures are aerosol-generating and pose a risk for the spread of airborne diseases, including COVID-19. Several aerosol mitigation strategies are available to reduce aerosol dispersion in dental clinics, such as increasing room ventilation and using extra-oral suction devices and high-efficiency particulate air (HEPA) filtration units. However, many questions remain unanswered, including what the optimal device flow rate is and how long after a patient exits the room it is safe to start treatment of the next patient. This study used computational fluid dynamics (CFD) to quantify the effectiveness of room ventilation, an HEPA filtration unit, and two extra-oral suction devices to reduce aerosols in a dental clinic. Aerosol concentration was quantified as the particulate matter under 10 µm (PM10) using the particle size distribution generated during dental drilling. The simulations considered a 15 min procedure followed by a 30 min resting period. The efficiency of aerosol mitigation strategies was quantified by the scrubbing time, defined as the amount of time required to remove 95% of the aerosol released during the dental procedure. When no aerosol mitigation strategy was applied, PM10 reached 30 µg/m3 after 15 min of dental drilling, and then declined gradually to 0.2 µg/m3 at the end of the resting period. The scrubbing time decreased from 20 to 5 min when the room ventilation increased from 6.3 to 18 air changes per hour (ACH), and decreased from 10 to 1 min when the flow rate of the HEPA filtration unit increased from 8 to 20 ACH. The CFD simulations also predicted that the extra-oral suction devices would capture 100% of the particles emanating from the patient's mouth for device flow rates above 400 L/min. In summary, this study demonstrates that aerosol mitigation strategies can effectively reduce aerosol concentrations in dental clinics, which is expected to reduce the risk of spreading COVID-19 and other airborne diseases.

Amelioration of oral mucositis pain by NASA near-infrared light-emitting diodes in bone marrow transplant patients.

PURPOSE: This study seeks to investigate the use of extra-orally applied near-infrared phototherapy for the reduction of oral pain secondary to chemotherapy- and radiation therapy-induced mucositis in adult and pediatric hematopoietic stem cell transplant (HSCT) patients. METHODS: Eighty HSCT patients were divided into regular (R) and low (L) risk groups, then to experimental (E) and placebo (P) groups, resulting in four groups (ER, EL, PR, PL). Experimental subjects received 670 (± 10) nm gallium-aluminum-arsinide light-emitting diode device for 80 s at ~50 mW/cm(2) energy density and power exposure of 4 J/cm(2). Placebo patients received the same procedures, but with a placebo phototherapy (identical device but <5 mW/cm(2) energy density). Patients received their respective light therapy once per day starting on the day of the HSCT (day 0) and continued through day +14. Blinded evaluators examined the patients three times per week and scored their oral tissues and patient-reported pain assessments at each evaluation utilizing the WHO, NCI-CTCAE, and OMAS scales. RESULTS: Analysis of the mean scores at each observation demonstrate that the extra-oral application of phototherapy resulted in a significant reduction in patient-reported pain between the ER and PR patients (p < 0.05) at day +14 when graded via the WHO criteria. The ER and EL patients were improved in almost all other categories and assessment scales, but the differences were not statistically significant. CONCLUSION: Phototherapy demonstrated a significant reduction in patient-reported pain as measured by the WHO criteria in this patient population included in this study. Improvement trends were noted in most other assessment measurements.

Hall Technique: Knowledge and Attitudes of Pediatric Dentists in the United States.

Purpose: To assess pediatric dentists' knowledge, attitudes, and factors associated with the use of the Hall technique (HT) in the United States.
Methods: An electronic questionnaire with a cover letter and consent form was sent to 6,277 active members of the American Academy of Pediatric Dentistry (AAPD) between April 15 and June 1, 2019. Descriptive and multivariate analyses were calculated.
Results: The response rate was 9.4 percent; 52 percent were males, 76 percent were white non-Hispanic, and 83 percent were in private practice. Ninety-seven percent were familiar with HT, and 39 percent had used it. Factors significantly associated with the use of HT were female dentists (P =0.01), patients with Medicaid insurance (P <0.001), rural locations (P =0.02), academic and community/public health clinics (P =0.004). Compared with AAPD members in the Western region, pediatric dentists in the North-Central region were more likely to use HT (odds ratio [OR] =2.50, 1.22 to 5.13, P =0.01) but pediatric dental residents in the North-Central region were less likely to use it (OR= 0.39,0.18 to 0.84, P =0.02).
Conclusion: Use of HT was considered a viable alternative in the management of dental caries. Despite the limitations of the technique, pediatric dentists' practice location and place of residency were significantly associated with its use.

A systematic review of dental disease in patients undergoing cancer therapy.

INTRODUCTION: This purpose of this systematic review was to evaluate the literature and update our current understanding of the impact of present cancer therapies on the dental apparatus (teeth and periodontium) since the 1989 NIH Development Consensus Conference on the Oral Complications of Cancer Therapies. REVIEW METHOD: A systematic literature search was conducted with assistance from a research librarian in the databases MEDLINE/PubMed and EMBASE for articles published between 1 January 1990 and 31 December 2008. Each study was independently assessed by two reviewers. Taking into account predetermined quality measures, a weighted prevalence was calculated for the prevalence of dental caries, severe gingival disease, and dental infection. Data on DMFT/dmft, DMFS/dmfs, plaque, and gingival indexes were also gathered. The level of evidence, recommendation, and guideline (if possible) were given for published preventive and management strategies. RESULTS: Sixty-four published papers between 1990 and 2008 were reviewed. The weighted overall prevalence of dental caries was 28.1%. The overall DMFT for patients who were post-antineoplastic therapy was 9.19 (SD, 7.98; n = 457). The overall plaque index for patients who were post-antineoplastic therapy was 1.38 (SD, 0.25; n = 189). The GI for patients who were post-chemotherapy was 1.02 (SD, 0.15; n = 162). The weighted prevalence of dental infections/abscess during chemotherapy was reported in three studies and was 5.8%. CONCLUSIONS: Patients who were post-radiotherapy had the highest DMFT. The use of fluoride products and chlorhexidine rinses are beneficial in patients who are post-radiotherapy. There continues to be lack of clinical studies on the extent and severity of dental disease that are associated with infectious complications during cancer therapy.

Dental sealants and restorative treatment for first molars among Medicaid enrollees.

OBJECTIVES: To assess the association between dental sealant placement and subsequent restorative treatment of permanent first molars over time. METHODS: We analysed Wisconsin Medicaid claims data from 2001 to 2009 for children aged 6-16 years. Children entered the study cohort at age 6 and were censored if Medicaid eligibility was lost for >31 days. A fixed effects analysis via a Cox proportional hazards model, stratified by individual, was used to estimate the time-averaged and time-dependent effects of sealant placement on dental treatment defined as any restorative, endodontic or surgical procedure. RESULTS: A total of 185,262 children with permanent first molars who turned 6 years enrolled in Medicaid were examined. Sealant placement was higher for teeth #16 and 26 (5.42 and 5.46 per 100 person-years (100PY), versus 5.29 and 5.31/100PY for #36 and 46, respectively. The average rate for restorative treatments had the opposite pattern, with lower rate for teeth #16 and 26 (1.78 and 1.72/100PY) versus teeth #36 and 46 (2.14 and 2.12/100PY), respectively. In the fixed effects regression model, the hazard of dental treatment was substantially lower after sealant placement on a tooth, with time-averaged hazard ratio HR = 0.23 (95% CI 0.21-0.25, P < .001) versus before sealant. The largest effect was in the first year after sealant placement (HR = 0.13, 95% CI: 0.11-0.14), which decreased over time (HR = 0.50, 0.59 and 0.74 in years 2, 3 and 4, respectively), and was not statistically significant in later years. CONCLUSIONS: This study demonstrates that permanent first molar sealant placement delayed subsequent dental treatments in children enrolled in Medicaid.

Factors associated with receipt of preventive dental treatment procedures among adult patients at a dental training school in Wisconsin, 2001-2002.

BACKGROUND: Gender differences in oral health-related quality of life and the fear of dental pain in seeking and receiving preventive dental care have been recognized and documented. Preventive dental treatment procedures (PDTPs) are commonly accepted as the primary approach to prevent dental disease. OBJECTIVE: We examined whether the likelihood of receiving PDTPs differed by gender in adult patients receiving dental care at a dental training institution in Milwaukee, Wisconsin. METHODS: Data from the Marquette University School of Dentistry electronic patient management database for 2001 through 2002 were analyzed. Descriptive, bivariate, and multivariable analyses were performed. The preventive procedures used in the study were those coded in accordance with the American Dental Association's classification system: D1110 (adult prophylaxis: professional cleaning and polishing of the teeth), D1204 (adult topical application of fluoride), D1205 (adult topical application of fluoride plus prophylaxis), and D1330 (oral hygiene instruction). RESULTS: Of the 1563 consecutive patient records (888 women, 675 men) reviewed for the years 2001-2002, 794 individuals (51%), aged 18 to 60 years, were identified as having received PDTPs. At the bivariate level, a significant gender difference in the receipt of PDTPs was identified (423 women [48%] vs 371 men [55%]; P = 0.004). In the multivariable analyses, age, race/ethnicity, marital status, poverty level, and health insurance type (public, private, none) were significantly associated with the receipt of PDTPs (all, P < 0.05), but gender was not. CONCLUSIONS: Gender differences in receiving PDTPs were not found in this dental school patient population. Receipt of PDTPs was associated with other demographic factors such as age, race/ethnicity, marital status, income level, and health insurance.

Pulp polyp associated with a natal tooth: case report.

Natal teeth are an infrequent occurrence at birth. Often these teeth are extracted because they are very mobile and pose a risk of aspiration. This is a rare case in which a natal tooth was extracted by the pediatrician with his fingers. A root fragment remained and out of this developed a large pulp polyp. This relationship has not been previously reported.

Prevalence of molar-incisor hypomineralization in Milwaukee, Wisconsin, USA: a pilot study.

Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7-12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.

Clinical and experimental applications of NIR-LED photobiomodulation.

This review presents current research on the use of far-red to near-infrared (NIR) light treatment in various in vitro and in vivo models. Low-intensity light therapy, commonly referred to as "photobiomodulation," uses light in the far-red to near-infrared region of the spectrum (630-1000 nm) and modulates numerous cellular functions. Positive effects of NIR-light-emitting diode (LED) light treatment include acceleration of wound healing, improved recovery from ischemic injury of the heart, and attenuated degeneration of injured optic nerves by improving mitochondrial energy metabolism and production. Various in vitro and in vivo models of mitochondrial dysfunction were treated with a variety of wavelengths of NIR-LED light. These studies were performed to determine the effect of NIR-LED light treatment on physiologic and pathologic processes. NIRLED light treatment stimulates the photoacceptor cytochrome c oxidase, resulting in increased energy metabolism and production. NIR-LED light treatment accelerates wound healing in ischemic rat and murine diabetic wound healing models, attenuates the retinotoxic effects of methanol-derived formic acid in rat models, and attenuates the developmental toxicity of dioxin in chicken embryos. Furthermore, NIR-LED light treatment prevents the development of oral mucositis in pediatric bone marrow transplant patients. The experimental results demonstrate that NIR-LED light treatment stimulates mitochondrial oxidative metabolism in vitro, and accelerates cell and tissue repair in vivo. NIR-LED light represents a novel, noninvasive, therapeutic intervention for the treatment of numerous diseases linked to mitochondrial dysfunction.

Children's Oral Health Assessment, Prevention, and Treatment.

This article provides a brief introduction to various aspects of oral health care in children, with emphasis on the epidemiology, risk assessment, prevention, and treatment modalities for dental caries. In addition, barriers to dental care and the involvement of pediatricians in advocating for and providing preventive dental care for children are reviewed. Oral health care is one of the most prevalent unmet needs among infants, toddlers, and adolescents in the United States. Routine or preventive dental visits are important for early diagnosis, prevention, and treatment of oral diseases, and for establishing and maintaining good oral health and overall well-being.

Mitochondrial signal transduction in accelerated wound and retinal healing by near-infrared light therapy.

Photobiomodulation by light in the red to near infrared range (630-1000 nm) using low energy lasers or light-emitting diode (LED) arrays has been shown to accelerate wound healing, improve recovery from ischemic injury in the heart and attenuate degeneration in the injured optic nerve. Recent evidence indicates that the therapeutic effects of red to near infrared light result, in part, from intracellular signaling mechanisms triggered by the interaction of NIR light with the mitochondrial photoacceptor molecule cytochrome c oxidase. We have demonstrated that NIR-LED photo-irradiation increases the production of cytochrome oxidase in cultured primary neurons and reverses the reduction of cytochrome oxidase activity produced by metabolic inhibitors. We have also shown that NIR-LED treatment prevents the development of oral mucositis in pediatric bone marrow transplant patients. Photobiomodulation improves wound healing in genetically diabetic mice by upregulating genes important in the promotion of wound healing. More recent studies have provided evidence for the therapeutic benefit of NIR-LED treatment in the survival and functional recovery of the retina and optic nerve in vivo after acute injury by the mitochondrial toxin, formic acid generated in the course of methanol intoxication. Gene discovery studies conducted using microarray technology documented a significant upregulation of gene expression in pathways involved in mitochondrial energy production and antioxidant cellular protection. These findings provide a link between the actions of red to near infrared light on mitochondrial oxidative metabolism in vitro and cell injury in vivo. Based on these findings and the strong evidence that mitochondrial dysfunction is involved in the pathogenesis of numerous diseases processes, we propose that NIR-LED photobiomodulation represents an innovative and non-invasive therapeutic approach for the treatment of tissue injury and disease processes in which mitochondrial dysfunction is postulated to play a role including diabetic retinopathy, age-related macular degeneration, Leber's hereditary optic neuropathy and Parkinson's disease.

Detection of known and novel genes encoding aromatic ring-hydroxylating dioxygenases in soils and in aromatic hydrocarbon-degrading bacteria.

Primers were designed and successfully used to screen aromatic hydrocarbon-degrading bacteria for the presence of class II aromatic ring-hydroxylating dioxygenase (RHD) genes and to amplify novel RHD genes from DNA extracted from soil using the polymerase chain reaction. Two previously undiscovered groups of genes encoding putative class II RHDs, designated the S and T clusters, were found in RHD different soil samples. Only one of 70 RHD gene fragments amplified from these soil samples could be assigned to a cluster of previously reported RHD genes. These results suggest that distinct and potentially numerically dominant groups of as-yet unrecognized aromatic hydrocarbon-degrading bacteria exist in soils.

Treatment of abscessed primary molars utilizing lesion sterilization and tissue repair: literature review and report of three cases.

PURPOSE: The purpose of this report was to review an emerging alternative treatment to pulpectomies and extractions for nonvital primary teeth called lesion sterilization and tissue repair (LSTR) and provide the results of three clinical case applications. LSTR is a noninstrumentation endodontic treatment that involves a triantibiotic mixture in a propylene glycol vehicle, which is used to disinfect root canal systems. This concept was developed by the cariology research unit of the School of Dentistry, Niigata University, Niigata, Niigata Prefecture, Japan. This article reviews the development of the technique, clinical procedures required for the technique, three clinical applications and radiographic documentation and follow-up, and a short literature review of the current evidence supporting its application in clinical practice.