ABSTRACT
PURPOSE: To evaluate the effects of low-level laser therapy (LLLT) on peri-implant bone regeneration by means of resonance frequency analysis and histologic analysis of bone-to-implant contact (BIC). MATERIALS AND METHODS: Thirty-two male New Zealand rabbits were randomly divided into four groups of eight animals each, one control group (nonirradiated animals) and three experimental groups that received LLLT (group E5 = 5 J per session; group E10 = 10 J per session; group E20 = 20 J per session). The mandibular left incisor was surgically extracted in all animals, and a nanoparticle-treated-surface osseointegrated implant was placed immediately afterward. The experimental groups were irradiated with aluminum-gallium-arsenide laser diode every 48 hours over a 13-day period for a total of seven sessions. Implant stability quotients (ISQs) were measured at the time of implant placement and 30 days after the last LLLT session. The animals were then euthanized and dissected, and histologic slides of the implant region were obtained for BIC evaluation. RESULTS: Significant differences in ISQ were detected between groups before and after LLLT, with group E20 showing significantly higher values than controls. The percentage of BIC was also significantly higher in group E20 than in control animals. CONCLUSION: Laser therapy at a dose of 20 J per treatment session, based on the irradiation protocol used in this study, was able to significantly increase ISQ values and BIC after implant placement, indicating that laser irradiation effected an improvement in peri-implant bone healing.
Subject(s)
Dental Implants , Low-Level Light Therapy/methods , Mandible/radiation effects , Osseointegration/radiation effects , Animals , Bone-Implant Interface/anatomy & histology , Bone-Implant Interface/radiation effects , Dental Implantation, Endosseous/methods , Dental Prosthesis Design , Dental Prosthesis Retention , Lasers, Solid-State/therapeutic use , Male , Mandible/anatomy & histology , Mandible/surgery , Nanoparticles/chemistry , Osteogenesis/radiation effects , Rabbits , Random Allocation , Surface Properties , Tooth Socket/anatomy & histology , Tooth Socket/radiation effects , Tooth Socket/surgery , VibrationABSTRACT
This in vitro study evaluated the effect of different apicoectomy angles, instruments used in root-end preparation, and dental materials used in retrofilling on apical sealing. Root ends were resected at 45 or 90 degrees in 80 single-rooted teeth. For each type of apicoectomy, root-end cavities were prepared with either a round carbide #2 bur or an S12/90D ultrasonic tip. The root-end cavities in each subgroup (apicoectomy + root-end preparation) were filled with silver amalgam without zinc (Am) or with gray mineral trioxide aggregate -Angelus (MTA), and the specimens were immediately immersed in 0.2% rhodamine B for 24 h. Sealing was evaluated based on the dyed cross-sectional dentin area. Data were analyzed statistically by the Kruskal-Wallis test at 5% significance level. No group showed complete sealing of root-end areas. The only significant factor affecting microleakage was dental material, with MTA exhibiting less leakage.
Subject(s)
Aluminum Compounds/chemistry , Apicoectomy/methods , Calcium Compounds/chemistry , Dental Amalgam/chemistry , Dental Bonding , Dental Leakage/classification , Fluorescent Dyes , Oxides/chemistry , Retrograde Obturation/methods , Root Canal Filling Materials/chemistry , Silicates/chemistry , Dental Pulp Cavity/ultrastructure , Dentin/ultrastructure , Drug Combinations , Equipment Design , Gutta-Percha/chemistry , Humans , Image Processing, Computer-Assisted/methods , Materials Testing , Retrograde Obturation/instrumentation , Rhodamines , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Time Factors , Ultrasonic Therapy/instrumentationABSTRACT
This in vitro study evaluated the effect of different apicoectomy angles, instruments used in root-end preparation, and dental materials used in retrofilling on apical sealing. Root ends were resected at 45 or 90 degrees in 80 single-rooted teeth. For each type of apicoectomy, root-end cavities were prepared with either a round carbide #2 bur or an S12/90D ultrasonic tip. The root-end cavities in each subgroup (apicoectomy + root-end preparation) were filled with silver amalgam without zinc (Am) or with gray mineral trioxide aggregate -Angelus (MTA), and the specimens were immediately immersed in 0.2 percent rhodamine B for 24 h. Sealing was evaluated based on the dyed cross-sectional dentin area. Data were analyzed statistically by the Kruskal-Wallis test at 5 percent significance level. No group showed complete sealing of root-end areas. The only significant factor affecting microleakage was dental material, with MTA exhibiting less leakage.
Este estudo in vitro avaliou o efeito de diferentes ângulos de apicectomia, instrumentos utilizados na retrocavitação e materiais odontológicos usados na retrobturação sobre selamento apical. Oitenta dentes unirradiculares, tratados endodonticamente, foram apicectomizados. Quarenta raízes tiveram seu ápice radicular seccionado com angulação de 45º e a outra metade com angulação de 90º. Para cada tipo de apicectomia realizou-se retrocavidades com broca esférica carbide nº 2 ou com retroponta ultra-sônica S12/90D. Cada subgrupo (apicectomia/retrocavidade) foi retrobturado com MTA ou amálgama, sendo os espécimes imediatamente imersos no corante Rodamina B a 0,2 por cento por 24 h. O selamento apical foi avaliado com base na área transversal de dentina corada ao redor da retrobturação. Os dados foram submetidos á análise estatística utilizando os testes de Kruskal-Wallis e Mann-Whitney. Nenhum grupo foi capaz de selar totalmente a região apical. O tipo de material utilizado na retrobturação foi o único fator que mostrou significativa diferença no selamento apical em relação à infiltração de corante.
