Performance of two laser motion modes versus conventional orthodontic ceramic brackets debonding technique on enamel surface topography.

The risk of enamel deterioration that frequently coexists with debonding of orthodontic teeth brackets elevates the mandate for finding an optimum approach for debonding them without harmful effects. This in-vitro study is intended to compare the effects of two different laser modes (scanning and circular) and a conventional method on the enamel surface after debonding orthodontic brackets. 66 extracted premolars were assigned into 3 groups. After that, light-cure composite resin was used to attach the ceramic brackets to the teeth. Amongst the test groups, Group I: specimens that were debonded using conventional debonding using pliers; Group 2: specimens that were debonded using Er, Cr: YSGG laser applications using the circular motion method; and Group 3: specimens that were debonded using Er, Cr: YSGG laser applications using the scanning motion method. Adhesive Remnant Index (ARI) assessment, intra-pulpal temperature increase, enamel surface roughness after polishing, and assessment of the microstructure of enamel were carried out with scanning electron microscopy. The gathered information was examined statistically. The conventional debonding method had a significantly higher proportion of adhesive remnant index (ARI) scores of 2 and 3 in comparison to the circular (p < .004) and scanning laser groups (p < .001). There was no significant difference in ARI scores between the circular and scanning laser groups (p > .05). Moreover, the circular and scanning laser debonding methods resulted in a significantly higher proportion of Enamel Surface Roughness (ESR) scores of 0 and a lower proportion of ESR scores of 3 compared to the conventional technique group (p < .001). However, there was no significant difference in ESR scores between the circular and scanning laser methods (p = .945). Lastly, the average intra-pulpal temperature was significantly higher in the circular laser group (1.9 ± 0.5 ) compared to the scanning laser group (0.9 ± 0.2) with p < .001. Er, Cr: YSGG laser irradiation is a tool that shows promise for debonding ceramic brackets with minimal harm to the enamel surface. The scanning laser technique is more desirable due to the lower intra-pulpal temperature increase.

The effect of aging on the translucency of contemporary zirconia generations: in-vitro study.

BACKGROUND: The translucency of different zirconia generations at each time point after thermocycling aging is still lacking. METHODS: Four zirconia materials were used with a total of 60 samples produced from monolithic third generation (5Y) 5 mol% yttria-stabilized zirconia polycrystalline ceramic and fourth generation zirconia (4Y) 4 mol% yttria-stabilized zirconia polycrystalline ceramic, represented by [group1:[CM-5Y] Ceramill Zolid fx (3rd generation zirconia) (Amann Girrbach, Koblach, Austria), group 2:[CM-4Y] Ceramill Zolid HT + (4th generation zirconia) (Amann Girrbach, Koblach, Austria), group 3:[CC-5Y] Cercon XT/ML (Dentsply Sirona, Germany) (3rd generation), and group 4:[CC-4Y] Cercon HT/ML (Dentsply Sirona, Germany) (4th generation)]. The L*a*b* figures were measured by using a spectrophotometer at baseline and after 10,000, 30,000, and 50,000 cycles of thermocycling. At each interval, the translucency of the samples was estimated by using the translucency formula CIEDE2000. The Scheffe post-hoc compared differences among each of the four materials. The Repeated measures ANOVA tested the differences between the materials at each of the different thermocycling intervals (p < .001). Data analyses were evaluated at a significance level of p < .05 (CI 95%). RESULTS: Two-way ANOVA revealed that at baseline the third and fourth generation's zirconia showed statistically significant differences in translucency (P < .001). Translucency values at baseline and after thermocycling exhibited statistically significant changes (p = .003). At each of the time interval; CM-4Y had the highest translucency values followed by CM-5Y, CC-4Y and CC-5Y had the least translucency values. CONCLUSIONS: The third and fourth generations of zirconia displayed different translucencies. Thermocycling affected the translucency of both third and fourth generations of zirconia. At each of the time intervals group 2:[CM-4Y] had the highest TP followed by group1:[CM-5Y], while, group 3:[CC-5Y] and group 4:[CC-4Y] had the least TP.

Esthetic patient satisfaction, marginal bone loss and peri-implant tissue success in esthetic zone: systematic review / Satisfação estética do paciente, perda óssea marginal e sucesso do tecido peri-implantar na zona estética: revisão sistemática

Increased patient demands for highly esthetic implant superstructure in the anterior esthetic zone has increased in the last decades. Moreover, the absence of periodontal ligament in implant supported prosthesis causes forces to be transferred without cushioning effect to the alveolar bone, resulting in increased marginal bone loss (MBL) and influence the heath of peri-implant tissue. Evaluate the available evidence on the effect implant superstructure and it consequences on patient satisfaction, MBL, bleeding on probing (BOP) and probing depth (PD). A protocol of electronic and hand research was performed for English based researches comparing implants inserted in the esthetic zone with all ceramic superstructure: "Will the use of different types of all ceramic superstructure show different esthetic patient satisfaction, marginal bone loss, bleeding on probing and probing depth? Thirteen publications from one thousand one hundred and sixteen research studies were included. This systematic review showed that all ceramic implant superstructure was a versatile treatment option with higher esthetic patient satisfaction and better color of peri-implant mucous especially in patients having thin biotype. On the other hand there wasn't significant difference in MBL, PD and BOP compared to other conventional implant superstructure. More randomized controlled clinical trials with bigger samples are needed to confirm our findings. All ceramic implant superstructure is versatile and highly esthetic treatment option for implant placed in the anterior esthetic zone.(AU)

A demanda do paciente por superestruturas de implante altamente estéticas na zona anterior aumentou nas últimas décadas. Além disso, a ausência de ligamento periodontal em próteses implantossuportadas faz com que as forças sejam transferidas para o osso alveolar sem amortecimento, resultando em aumento da perda óssea marginal (MBL) e influenciando na saúde do tecido peri-implantar. Avaliar as evidências disponíveis sobre o efeito da superestrutura do implante e suas consequências na satisfação do paciente, perda óssea marginal, sangramento à sondagem (SS) e profundidade de sondagem (PS). Um protocolo de pesquisa eletrônica e manual foi realizado para a análise de artigos em inglês comparando implantes com toda a superestrutura em cerâmica inseridos na zona estética: "O uso de diferentes tipos de superestrutura em cerâmica mostrará diferentes níveis de satisfação estética do paciente, perda óssea marginal, sangramento em profundidade de sondagem e sondagem?". Foram selecionadas 1116 publicações e apenas treze estudos foram incluídos na análise final. Esta revisão sistemática mostrou que toda superestrutura do implante em cerâmica foi uma opção de tratamento versátil, com maior satisfação estética do paciente e melhor coloração da mucosa peri-implantar, especialmente em pacientes com biótipo fino. Por outro lado, não houve diferença significativa em MBL, PS e SS em comparação com outras superestruturas de implantes convencionais. Porém, mais ensaios clínicos controlados randomizados com amostras maiores são necessários para confirmar nossos achados. Implicações clínicas: Toda superestrutura do implante em cerâmica é uma opção de tratamento versátil e altamente estética para implantes colocados na zona anterior (AU)