Does radiotherapy treatment alter the pulp condition in patients with head and neck cancer? A systematic review.

The main purpose of this study was to answer the question: "Can radiotherapy cause changes in the dental pulp condition of patients treated with irradiation in the head and neck region?" Clinical observational studies in adults with head and neck cancer undergoing treatment with ionizing radiation, longitudinal or cross-sectional follow-up to measure oxygen saturation (SpO2), and/or pulp sensitivity test to cold stimulation, were considered eligible. A systematic literature search was performed in six different databases, including the gray literature, and in article references. Two independent evaluators selected the studies, extracted the data, recorded the data on electronic spreadsheets, and then evaluated the methodological quality using the Checklist for Quasi-Experimental Studies tool devised by JBI. The data were assessed qualitatively using the Synthesis Without Metanalysis (SWiM) guidelines. After removing the duplicate articles, carefully analyzing the titles and abstracts, and reading the papers in full, seven studies were included. Four of the studies evaluated applied the cold sensitivity test, two associated pulse oximetry and cold sensitivity, and only one used just pulse oximetry. Evaluation using the cold sensitivity test and pulse oximetry in the initial periods before radiotherapy showed a decrease in the sensitive response and in SpO2 levels during a maximum period of 1 year. However, analyses thereafter indicated a normal response in both tests from 5 to 6 years after the end of radiotherapy treatment. Radiotherapy causes changes in pulp behavior patterns in the short term; however, recovery and return to average values occurs after long periods.

Does irradiation of the tooth structure interfere with oxygen saturation measured by pulse oximetry?-An ex vivo laboratorial study.

The effect of tooth structure subjected to ionising radiation on oxygen saturation levels (SpO2 ) measured by pulse oximetry was investigated. Fifty-four extracted human third molars were sectioned mesiodistally. Pulse oximeter diodes were placed in prefabricated silicone moulds, secured on a vise with tooth surfaces placed between the diodes and the participant's finger, and SpO2 levels were measured. After that, the tooth surfaces were subjected to ionising radiation in fractionated doses of up to 70 Gy, and SpO2 was measured according to the protocol described. The Kolmogorov-Smirnov test was used for the analysis of normality of the quantitative variables, and Student's t-test compared mean SpO2 levels before and after irradiation. Mean SpO2 after irradiation was 94.6 ± 0.9%, without a statistically significant difference from SpO2 before irradiation, which was 94.7 ± 0.6%. Irradiation of the tooth structure did not interfere with SpO2 levels measured by pulse oximetry.

Does radiotherapy treatment alter the pulp condition in patients with head and neck cancer? A systematic review

Abstract The main purpose of this study was to answer the question: "Can radiotherapy cause changes in the dental pulp condition of patients treated with irradiation in the head and neck region?" Clinical observational studies in adults with head and neck cancer undergoing treatment with ionizing radiation, longitudinal or cross-sectional follow-up to measure oxygen saturation (SpO2), and/or pulp sensitivity test to cold stimulation, were considered eligible. A systematic literature search was performed in six different databases, including the gray literature, and in article references. Two independent evaluators selected the studies, extracted the data, recorded the data on electronic spreadsheets, and then evaluated the methodological quality using the Checklist for Quasi-Experimental Studies tool devised by JBI. The data were assessed qualitatively using the Synthesis Without Metanalysis (SWiM) guidelines. After removing the duplicate articles, carefully analyzing the titles and abstracts, and reading the papers in full, seven studies were included. Four of the studies evaluated applied the cold sensitivity test, two associated pulse oximetry and cold sensitivity, and only one used just pulse oximetry. Evaluation using the cold sensitivity test and pulse oximetry in the initial periods before radiotherapy showed a decrease in the sensitive response and in SpO2 levels during a maximum period of 1 year. However, analyses thereafter indicated a normal response in both tests from 5 to 6 years after the end of radiotherapy treatment. Radiotherapy causes changes in pulp behavior patterns in the short term; however, recovery and return to average values occurs after long periods.

Cyclic Fatigue and Torsional Strength of a New Thermally Treated Reciprocating System.

OBJECTIVE: This study evaluated the resistance to cyclic fatigue and the torsional strength of Prima One Gold® and WaveOne Gold® reciprocating systems. METHODS: Cyclic fatigue was tested in an artificial canal with 60º curvature, a 5 mm radius of curvature at 22°C (n=10) and 36.5°C (n=10). The torsional strength test followed ISO 3630-1, measuring torque and deflection angle until fracture (n=10). The t-test was used to compare the two groups, and the significance level was set at 5%. RESULTS: The Prima One Gold group presented greater resistance to cyclic fatigue at room temperature (P=0.001) and body temperature (P<0.001). For the torsional resistance test, the Prima One Gold group had a lower maximum torque value (P=0.029), despite having a greater deflection angle (P<0.001). CONCLUSION: The Prima One Gold group showed greater resistance to cyclic fatigue regardless of temperature and a greater deflection angle. The WaveOne Gold group showed a greater maximum torque value than the Prima One Gold group.

Effects of fractionation and ionizing radiation dose on the chemical composition and microhardness of enamel.

OBJECTIVE: To evaluate the chemical and mechanical properties of enamel submitted to different in vitro radiation protocols. DESIGN: Third molars were divided into seven groups (n = 8): non-irradiated (NI); a single dose of 30 Gy (SD30), 50 Gy (SD50), or 70 Gy (SD70) of radiation; or fractional radiation doses of up to 30 Gy (FD30), 50 Gy (FD50), or 70 Gy (FD70). Hemisections were analysed by Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDS) and Knoop microhardness (KHN) test. One-way ANOVA followed by Bonferroni's post-hoc test compared the test groups with the NI. Two-way ANOVA was performed for the fractionation and radiation dose, followed by Bonferroni's test (α = 0.05). RESULTS: FTIR revealed differences for the amide I band between the NI and FD50 and NI and FD70 groups (p < 0.001). For the organic matrix/mineral ratio, the FD70 group presented a lower ratio compared to NI (p = 0.009). Excluding the NI group, there were differences between the FD30 and FD50 (p = 0.045) and the FD30 and FD70 groups (p < 0.001). For EDS, there were differences for Ca (p = 0.011) and Ca/P (p < 0.001), with the FD70 group presenting lower values compared to NI (p = 0.015; p < 0.001). For KHN, the FD70 group presented lower values than the NI (p = 0.002). Two-way ANOVA showed difference for the dose (p < 0.001), with the 70 Gy group presenting a lower KHN value within the fractionated groups. CONCLUSION: Fractional doses 70 Gy irradiation caused chemical and mechanical changes to enamel. Radiation applied in single or fractional doses produced different effects to enamel.

Interdisciplinaridade no tratamento de ceratocisto odontogênico: relato de caso / Interdisciplinary in the treatment of odontogenic keratocyst: case report

O Ceratocisto Odontogênico (CO) é um cisto de desenvolvimento odontogênico relativamente prevalente na população e com caráter eventual de agressividade com crescimento ântero- -posterior insidioso. Trata-se de uma lesão cuja apresentação é extremamente diversa com relação à faixa etária, gênero e aspectos imaginológicos mais prevalentes. O presente trabalho relata o caso de um garoto de 11 anos de idade, portador de uma extensa lesão mandibular, envolvendo desde o dente 33 até o 46, cuja microscopia foi compatível com CO. O artigo aborda toda a conduta propedêutica conduzida pela equipe a nível ambulatorial, bem como a interdisciplinaridade com a ortodontia, possibilitando um desfecho almejado e satisfatório do caso.

Keratocyst Odontogenic (KO) is a cyst of odontogenic development relatively prevalent in the population and with an eventual aggressive character with insidious antero-posterior growth. It is a lesion whose presentation is extremely diverse in relation to age, gender and most prevalent imaging aspects. This paper reports the case of an 11 - year - old boy with an extensive mandibular lesion, evolving from tooth 33 to 46, whose microscopy was compatible with KO. The article deals with all the propaedeutic conduct conducted by the team at the outpatient level, as well as the interdisciplinarity with orthodontics, enabling a desired and satisfactory outcome of the case.