Challenges, limitations, and solutions for orthodontists during the coronavirus pandemic: A review.

INTRODUCTION: Orthodontic patients worldwide missed appointments during the early months of the coronavirus disease 2019 (COVID-19) pandemic. A significant problem with this virus is its high transmission power. Asymptomatic patients can transmit the virus. The aim of this review is to examine orthodontic emergencies and the necessary strategies and measures for emergency and nonemergency treatment during the coronavirus pandemic. METHODS: The following databases were comprehensively searched: PubMed, MEDLINE, Scopus, and Google Scholar. Up-to-date data released by major health organizations such as the World Health Organization and major orthodontic associations involved in the pandemic were also evaluated. RESULTS: Few studies were conducted on managing orthodontic offices or clinics during the pandemic, and most are not of high quality. Appropriate communication is the most important issue in managing orthodontic patients, particularly virtual counseling. Many orthodontic emergencies can be managed in this way by patients themselves. Most studies recommend using the filtering facepiece 2 masks, equivalent to N95 masks for non-COVID-19 patients undergoing aerosol-generating procedures and all suspected or confirmed COVID-19 patients in orthodontic visits. CONCLUSIONS: At this time, there are no definitive clinical protocols supported by robust evidence for orthodontic practice during the COVID-19 pandemic. Orthodontists should not rush to return to routine orthodontic work and should follow state guidelines. Nonemergency orthodontic visits should be suspended during the severe acute respiratory syndrome coronavirus 2 pandemic in high-risk areas. Resuming orthodontic procedures during the pandemic requires paying special attention to screening, performing maximum efforts to reduce aerosol generation, using appropriate personal protective equipment, having proper ventilation, and fully adhering to sterilization and disinfection principles.

Comparison of conventional and laser-aided fiberotomy in relapse tendency of rotated tooth: A randomized controlled clinical trial.

INTRODUCTION: The aim of the present study was to compare the tendency of mandibular incisor rotation relapse after conventional circumferential supracrestal fiberotomy (CSF) with Er,Cr:YSGG laser-aided CSF. METHODS: In this three-arm parallel study, the patients with one lower incisor rotation greater than 30 degrees before treatment were selected. The patients were randomly assigned to three groups in a 1:1:1 ratio. Rotational relapse tendency was measured on a digitized model one month after arch wire removal. Probing depth, clinical crown height and pain levels were also measured. RESULTS: A total of 46 patients were recruited. Relapse tendency in conventional CSF and laser-aided CSF groups were 5.09±1.59° and 4.87±2.08°, respectively, and significantly lower than 11.28±2.93° in the control group (P<0.001). Relapse tendency was not different between the conventional CSF and laser CSF groups. Probing depth, clinical crown height, and experienced pain levels exhibited negligible differences. CONCLUSIONS: Er,Cr:YSGG laser-aided CSF in one month was as effective in reducing rotational relapse tendency of mandibular incisor teeth as conventional CSF.

Effect of CPP-ACP paste with and without CO2 laser irradiation on demineralized enamel microhardness and bracket shear bond strength.

INTRODUCTION:: Many patients seeking orthodontic treatment already have incipient enamel lesions and should be placed under preventive treatments. The aim of this in vitro study was to evaluate the effect of CPP-ACP paste and CO2 laser irradiation on demineralized enamel microhardness and shear bond strength of orthodontic brackets. METHODS:: Eighty caries-free human premolars were subjected to a demineralization challenge using Streptococcus mutans. After demineralization, the samples were randomly divided into five equal experimental groups: Group 1 (control), the brackets were bonded without any surface treatment; Group 2, the enamel surfaces were treated with CPP-ACP paste for 4 minutes before bonding; Group 3, the teeth were irradiated with CO2 laser beams at a wavelength of 10.6 µm for 20 seconds. The samples in Groups 4 and 5 were treated with CO2 laser either before or through CPP-ACP application. SEM photomicrographs of a tooth from each group were taken to observe the enamel surface. The brackets were bonded to the buccal enamel using a conventional method. Shear bond strength of brackets and ARI scores were measured. Vickers microhardness was measured on the non-bonded enamel surface. Data were analyzed with ANOVA and Tukey test at the p< 0.05 level. RESULTS:: The mean shear bond strength and microhardness of the laser group were higher than those in the control group and this difference was statistically significant (p< 0.05). All groups showed a higher percentage of ARI score 4. CONCLUSION:: CO2 laser at a wavelength of 10.6 µm significantly increased demineralized enamel microhardness and enhanced bonding to demineralized enamel.

Effect of CPP-ACP paste with and without CO2 laser irradiation on demineralized enamel microhardness and bracket shear bond strength

ABSTRACT Introduction: Many patients seeking orthodontic treatment already have incipient enamel lesions and should be placed under preventive treatments. The aim of this in vitro study was to evaluate the effect of CPP-ACP paste and CO2 laser irradiation on demineralized enamel microhardness and shear bond strength of orthodontic brackets. Methods: Eighty caries-free human premolars were subjected to a demineralization challenge using Streptococcus mutans. After demineralization, the samples were randomly divided into five equal experimental groups: Group 1 (control), the brackets were bonded without any surface treatment; Group 2, the enamel surfaces were treated with CPP-ACP paste for 4 minutes before bonding; Group 3, the teeth were irradiated with CO2 laser beams at a wavelength of 10.6 µm for 20 seconds. The samples in Groups 4 and 5 were treated with CO2 laser either before or through CPP-ACP application. SEM photomicrographs of a tooth from each group were taken to observe the enamel surface. The brackets were bonded to the buccal enamel using a conventional method. Shear bond strength of brackets and ARI scores were measured. Vickers microhardness was measured on the non-bonded enamel surface. Data were analyzed with ANOVA and Tukey test at the p< 0.05 level. Results: The mean shear bond strength and microhardness of the laser group were higher than those in the control group and this difference was statistically significant (p< 0.05). All groups showed a higher percentage of ARI score 4. Conclusion: CO2 laser at a wavelength of 10.6 µm significantly increased demineralized enamel microhardness and enhanced bonding to demineralized enamel.

RESUMO Introdução: muitos pacientes, ao buscar o tratamento ortodôntico, já apresentam lesões incipientes no esmalte e precisam ser submetidos a tratamentos preventivos. O objetivo do presente estudo in vitro foi avaliar o efeito da pasta CPP-ACP e da irradiação com laser de CO2 na microdureza do esmalte desmineralizado e na resistência ao cisalhamento de braquetes ortodônticos. Métodos: oitenta pré-molares humanos hígidos foram submetidos a desmineralização usando Streptococcus mutans. Após a desmineralização, as amostras foram divididas aleatoriamente em cinco grupos experimentais: Grupo 1 (controle), os braquetes foram colados sem qualquer tratamento de superfície; Grupo 2, a superfície do esmalte foi tratada com pasta CPP-ACP por 4 minutos antes da colagem; Grupo 3, os dentes foram irradiados com laser de CO2 no comprimento de onda de 10,6 µm, por 20 segundos; Grupos 4 e 5, as amostras foram tratadas com laser de CO2 antes ou durante a aplicação de CPP-ACP. Foram feitas fotomicrografias por Microscopia Eletrônica de Varredura (MEV) de um dente de cada grupo, para avaliação da superfície do esmalte. Os braquetes foram colados ao esmalte na face vestibular, usando-se o método convencional. Foram medidos a resistência ao cisalhamento dos braquetes e o escore do Índice de Adesivo Remanescente (ARI). A microdureza Vickers foi medida nas superfícies do esmalte onde não foi realizada colagem. Os dados foram analisados com ANOVA e teste Tukey ao nível de p< 0,05. Resultados: a média da força de resistência ao cisalhamento e da microdureza do grupo laser foi superior à do grupo controle, com diferença estatisticamente significativa (p < 0,05). Todos os grupos apresentaram maior porcentagem do escore ARI=4. Conclusões: o laser de CO2 no comprimento de onda de 10,6 µm aumentou significativamente a microdureza do esmalte desmineralizado e melhorou a adesão dos braquetes nele.