An Evaluation of the Effects of Photobiomodulation Therapy on the Peri-Implant Bone Healing of Implants with Different Surfaces: An In Vivo Study.

(1) Background: This study evaluates the effects of photobiomodulation (PBM) therapy on the peri-implant bone healing of implants with a machined surface (MS) and treated surface (TS). (2) Methods: Topographic characterization of the surfaces (scanning electron microscopy [SEM]- energy dispersive X-ray spectroscopy [EDX]) was performed before and after implant removal. Twenty rabbits were randomly divided into four groups: MS and TS groups (without PBM therapy) and LMS and LTS groups (with PBM therapy). After implant placement, the stability coefficient (ISQ) was measured. In the periods of 21 and 42 days, the ISQ was measured again, followed by biomechanical analysis. (3) Results: The surfaces of the TS implants showed topographic differences compared with MS implants. The ISQ values of the LMS were statistically significant when compared with those of the MS at 42 days (p < 0.001). The removal torque values of the LMS were statistically significant when compared with those of the MS at 21 days (p = 0.023) and 42 days (p = 0.023). For SEM, in general, the LMS, TS and LTS presented high bone tissue coverage when compared to MS. (4) Conclusions: The PBM therapy modulated the osseointegration process and was evidenced mainly on the machined surface.

Intentionally Exposed d-PTFE Membrane and Guided Bone Regeneration after Malpositioned Dental Implant in Anterior Area: A Case Report with 1-year Follow-up.

This article describes the removal of a malpositioned dental implant, using an implant retriever, followed by guided tissue regeneration with the use of an xenogeneic graft and a dense polytetrafluorethylene membrane that remained partially exposed for 28 days, and the post-surgical prosthetic and orthodontic treatment until conclusion of the oral rehabilitation procedure. The patient, 50 years of age, presented to a private clinic for evaluation of an implant supported fixed crown, with unsatisfactory esthetic appearance and function. The treatment plan involved the removal of this implant, guided bone regeneration, and placement of a new implant in a better 3D position. Subsequently, the patient received a provisional dental prosthesis, orthodontic treatment in order to realign the gingival margins, and additional rehabilitation with the application of some ceramic veneers to enhance the patient's esthetic appearance, improve function, and show the 1-year follow-up of the case. The treatment plan was shown to be appropriate for this case, in which soft and hard tissue were adequately regenerated, and resulted in good oral rehabilitation with tissue stability around the teeth and implant.

Comparative in vivo study of alloy titanium implants with two different surfaces: biomechanical and SEM analysis.

OBJECTIVES: The purpose of this study was to evaluate the biomechanical behavior of the interface formed between bone and implants with machined surfaces (MS) and those modified by Al2O3 sandblasting and acid etching (SBAS). MATERIALS AND METHODS: Before surgery, topographic characterization was performed by SEM-EDX and by mean roughness measurements. Ten Albinus rabbits received randomly 20 Ti-6Al-4V implants on its right and left tibiae, with one implant placed in each tibia. After implant insertion, the implant stability quotient (ISQ) was measured by means of resonance frequency analysis (RFA). After 3 and 6 weeks, the ISQ was again measured, followed by torque removal measurements. Analysis of variance and Tukey tests were used to analyze the data. The surface of the implants removed was evaluated by SEM-EDX. Immunohistochemical analysis of osteopontin (OPN) and osteocalcin (OC) protein was performed in bone tissue. RESULTS: The topographic characterization showed differences between the analyzed surfaces, and the mean roughness values of SBAS group were statistically higher than MS. Overall, higher statistically significant ISQ values were observed in the SBAS group compared to the MS group (p = 0.012). The intra-group comparison of ISQ values in the SBAS group showed statistically significant differences between 0 and 3 weeks (p = 0.032) and 0 and 6 weeks (p = 0.003). The torque removal measurements of group SBAS were statistically higher when compared with the torque removal measurements of group MS in the time intervals of 3 weeks (p = 0.002) and 6 weeks (p < 0.001). SEM-EDX of the implant surfaces removed in SBAS group showed greater bone tissue covering and mean values atomic in percentage of Ca, P, and O statistically superior (p < 0.05) than MS group. Immunohistochemical reactions showed intense OC immunolabeling at 6 weeks postoperative for SBAS group. CONCLUSIONS: The topographical modifications made in group SBAS allowed a better mechanical interlocking between the implant and bone tissue.

Desajuste vertical entre implante de hexágono interno e pilares Ucla totalmente calcináveis e com base de CoCr após a fundição pelo processo convencional / Vertical misfit between internal hexagon implants and Ucla burnout and CoCr prefabricated base abutments after conventional casting procedures

Objetivo: avaliar, por meio de um microdurômetro, o grau de desajuste na adaptação de pilares Ucla em implantes. Material e métodos: foram utilizados dez implantes de hexágono interno de plataforma regular, e seus respectivos componentes protéticos do tipo Ucla com antirrotacional, como seguem: dez pilares Ucla totalmente calcináveis e dez pilares Ucla com base de CoCr. Todos os pilares Ucla foram fundidos pelo mesmo laboratório de prótese e pelo mesmo processo laboratorial. Cada implante recebeu apenas dois pilares, que foram anexados por meio de um parafuso de titânio quadrado utilizando-se torque de 30 Ncm com torquímetro manual. Cada conjunto implante/pilar recebeu quatro marcações aleatórias em torno da circunferência, na qual foram feitas as medições do espaço existente entre as peças utilizando uma lupa estereoscópica de 100 vezes de aumento. Resultados: os resultados obtidos mostraram diferenças significativas entre os grupos submetidos ao teste Mann-Whitney (p < 0,05). Conclusão: o pilar Ucla com base de CoCr apresentou menor desajuste marginal vertical, quando comparado ao pilar Ucla totalmente calcinável, após o processo de fundição nos implantes de hexágono interno.

Objective: to evaluate, using a microhardness device, the misfit between Ucla abutments and internal hex implants. Material and methods: 10 internal hex implants received 10 Ucla burnout and 10 Ucla abutments with CoCr collar. All the abutments were cast in the same laboratory and under the same protocol. A square-head titanium screw was tightened to a 30 Ncm using a manual wrench. Each abutment/implant set receive four random markings around its perimeter. A stereoscopic lens was used to investigate the misfi t at 100 magnification. Results: there was a statistically significant difference between tested abutments (Mann-Whitney p < 0.05). Conclusion: the Ucla abutment with the CoCr collar presented less vertica misfit values after casting for internal hex dental implants.

Preservação do rebordo alveolar com perda óssea vestibular associada a biomaterial e membrana PTFE densa intencionalmente exposta ao meio bucal / Preservation of the alveolar ridge with buccal bone loss associated with biomaterial and d-PTFE membrane intentionally exposed to the buccal environment

O uso de membranas em casos de regeneração óssea guiada tornou-se comum e representa um recurso para ganho de tecido ósseo. As membranas de politetrafluoretileno denso (d-PTFE) são uma opção quando há necessidade de mantê-las expostas ao meio bucal. Neste estudo, relata-se a utilização de uma membrana d-PTFE para regeneração óssea em alvéolo pós-extração em região estética.

The use of membranes in cases of guided bone regeneration has become common and represents a resource for bone tissue gain. Dense polytetrafl uoroethylene (d-PTFE) membranes are an option when there is a need to keep them exposed in the oral cavity. In this study, we report the use of a d-PTFE membrane for bone regeneration in the post-extraction socket in the esthetic zone.