Short-term immunosuppressive therapy does not affect the density of the pre-existing bone around titanium implants placed in rabbits

O objetivo deste trabalho foi avaliar a influência da administração de ciclosporina A (CsA)/nifedipina e sua interrupção na densidade óssea em uma região lateral à superfície de implantes de titânio inseridos em coelhos. Dois implantes de titânio comercialmente puros foram inseridos bilateralmente em vinte e oito coelhos. Os animais foram aleatoriamente divididos em um dos seguintes grupos experimentais, recebendo injeções diárias subcutâneas por 14 dias: Grupos A e C: veículo (dimetil sulfóxido); Grupos B e D: CsA (10 mg/kg) e nifedipina (50 mg/kg). Os animais pertencentes aos Grupos A/B e C/D foram sacrificados 14 e 42 dias após a colocação dos implantes, respectivamente. Após o sacrifício, as tíbias foram removidas para a obtenção de secções não-descalcificadas. A densidade óssea foi obtida em uma zona de 500 mm lateral à superfície do implante através de análise histométrica. A análise intergrupo não revelou diferenças para os grupos teste e controle em 14 e 42 dias (p >; 0,05). Dentro dos limites deste estudo podemos concluir que a associação CsA/nifedipina, administrada em um curto prazo, não apresenta uma influência negativa na densidade do osso preexistente ao redor de implantes de titânio inseridos em coelhos.The aim of this study was to evaluate the influence of the administration and withdrawal of cyclosporin A/nifedipine on the bone density in a lateral area adjacent to implants placed in rabbits. Two screw-type titanium implants were placed bilaterally in twenty-eight New Zealand rabbits. The animals were assigned to one of the following groups and received daily subcutaneous injections for 14 days: Groups A and C: vehicle (dimethyl sulfoxide); Groups B and D: CsA (10 mg/kg) plus nifedipine (50 mg/kg). The animals in Groups A and B were sacrificed 14 days postoperatively and, in Groups C and D, 42 days postoperatively. After sacrifice, the tibiae were removed and undecalcified sections were obtained. Bone density was obtained in a 500 mm-wide zone lateral to the implant surface. Intergroup analysis showed no significant difference (p >; 0.05) in the degree of bone density between control and test groups either on day 14 or on day 42. Thus, it appears that a short-term immunosuppressive therapy may not present a negative influence on the density of the pre-existing bone around titanium implants placed in rabbits

Efeito de uma única sessão de controle de placa supragengival nos parâmetros clínicos e bioquímicos da periodontite crônica

Supragingival plaque control is a requisite for the success of any periodontal procedure. However, little is know about the effect of this procedure alone on periodontitis. The aim of this study was to determine the effect of supragingival plaque control on clinical and biochemical parameters of chronic periodontitis. Twenty-five subjects exhibiting at least 4 pockets >; 5mm, non-smokers and with no relevant systemic diseases, were selected for the study. The clinical and biochemical assessments were done before and 21 days after removal of plaque retentive factors, extraction of affected teeth and instruction in oral hygiene. The statistical analysis was done with the Student paired t-test (pO objetivo deste estudo foi avaliar o efeito do controle de placa supragengival sobre os parâmetros clínicos e bioquímicos da periodontite crônica. Foram selecionados 25 pacientes apresentando pelo menos 4 sítios com profundidade de sondagem >; 5 mm, não fumantes e sem alterações sistêmicas relevantes. A avaliação clínica e bioquímica foi feita antes e 21 dias após a remoção dos fatores retentivos de placa, exodontia dos dentes condenados e instrução de higiene bucal. A análise estatística foi feita através do teste t de Student pareado (

Non-surgical instrumentation associated with povidone-iodine in the treatment of interproximal furcation involvements

OBJECTIVE: The aim of this controlled clinical trial was to evaluate the effect of topically applied povidone-iodine (PVP-I) used as an adjunct to non-surgical treatment of interproximal class II furcation involvements. MATERIAL AND METHODS: Thirty-two patients presenting at least one interproximal class II furcation involvement that bled on probing with probing pocket depth (PPD) >;5 mm were recruited. Patients were randomly chosen to receive either subgingival instrumentation with an ultrasonic device using PVP-I (10%) as the cooling liquid (test group) or identical treatment using distilled water as the cooling liquid (control group). The following clinical outcomes were evaluated: visible plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PPD and relative horizontal attachment level (RHAL). BAPNA (N-benzoyl-L-arginine-p-nitroanilide) testing was used to analyze trypsin-like activity in dental biofilm. All parameters were evaluated at baseline and 1, 3 and 6 months after non-surgical subgingival instrumentation. RESULTS: Six months after treatment, both groups had similar means of PPD reduction, RAL and RHAL gain (p>;0.05). These variables were, respectively, 2.20±1.10 mm, 1.27±1.02 mm and 1.33±0.85 mm in the control group and 2.67±1.21 mm, 1.50±1.09 mm and 1.56±0.93 mm in the test group. No difference was observed between groups at none of the posttreatment periods, regarding the number of sites showing clinical attachment gain >;2 mm. However, at 6 months posttreatment, the test group presented fewer sites with PPD >;5 mm than the control group. Also at 6 months the test group had lower BAPNA values than control group. CONCLUSION: The use of PVP-I as an adjunct in the non-surgical treatment of interproximal class II furcation involvements provided limited additional clinical benefits

Estudo comparativo in vitro da rugosidade radicular após instrumentação com ultrassom e pontas sônicas diamantadas

OBJECTIVE: The purpose of this study was to evaluate the root surface roughness after instrumentation with hand curette and diamond-coated sonic and universal ultrasonic tips. MATERIALS AND METHODS: Forty root surfaces of human teeth were randomly assigned to four treatment groups: control group (without instrumentation), curette instrumentation, ultrasonic instrumentation with universal tip and sonic instrumentation with diamond-coated tip. Each sample was instrumented with fifteen strokes. Before and after instrumentation, surface roughness was measured. In addition, the root surface topography was examined after treatment under the scanning electron microscope. RESULTS: Significant statistical differences (p ;0.05). CONCLUSION: The diamond-coated tip with sonic scaler instrumentation and ultrasonic instrumentation produce similar root surface roughness, higher than curette instrumentation.OBJETIVO: O objetivo do presente estudo foi avaliar a rugosidade radicular obtida após instrumentação por aparelho sônico com pontas diamantadas, curetas e ultrassom. MATERIAL E MÉTODOS: Quarenta superfícies radiculares, devidamente polidas e incluídas em resina acrílica, foram dividas em 4 grupos de tratamento: grupo controle (sem instrumentação) e instrumentação com cureta Gracey 5/6, ultrassom ou aparelho sônico com ponta diamantada. Em cada amostra foram realizados 15 movimentos de raspagem. Antes e após esta instrumentação foi utilizado um rugosímetro para a medição da rugosidade radicular. Além disso, a topografia da superfície radicular foi avaliada após o tratamento com microscopia eletrônica de varredura. RESULTADOS: Diferenças estatisticamente significantes (p;0.05). CONCLUSÃO: A instrumentação sônica com pontas diamantadas promove uma rugosidade radicular equivalente à instrumentação com ultrassom, sendo essa rugosidade superior àquela apresentada pela instrumentação manual

Decision making in the treatment of class III furcation: resective therapy? Extraction? Implant?

The presence of furcation lesions is associated with bone resorption and lack of insertion in the inter-radicular space, and is a condition that considerably increases the risk of dental loss, particularly in the absence of adequate treatment. In this context, the object of some of the therapies is to keep teeth with furcation lesions that are important to dental planning, to re-establish an anatomy that enables the patient to remove dental biofilm from the compromised area. However, the long term maintenance and treatment of molars with Class III furcation lesions continues to be a challenge to dentists during periodontal therapy, since the anatomy of the inter-radicular region makes it difficult for both professionals and patients to gain access to perform adequate and efficient control of dental biofilm. The impossibility of obtaining appropriate decontamination of the area involved during the root scraping process, including by means of surgical access, demands thatdentists have adequate knowledge to determine the correct therapeutic approach during the treatment of teeth with advance inter-radicularbone loss. The aim of the present study was to discuss the treatments available for Class III furcation lesions and relate clinical procedures that could be performed for the treatment of this type of defect

O uso da clorexidina em periodontia. Uma revisão de literatura.

O uso da clorexidina em periodontia. Uma revisão de literatura

Cigarette smoke inhalation influences bone healing of post-extraction tooth socket: a histometric study in rats

The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p&gt;0.05) for all parameters. On the 7th day, CSI affected negatively (p<0.05) bone formation with respect to NMT and RA (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, for the control and test groups, respectively). In contrast, no statistically significant differences (p&gt;0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers

Intermittent Cigarette Smoke Inhalation May Affect Bone Volume Around Titanium Implants In Rats.

A negative influence of smoking on implant outcomes has been reported. This animal study investigated the influence of cigarette smoke on osseointegration and newly formed bone within implant threads. Male Wistar rats were included in the study. After anesthesia, the tibiae surface was exposed and a screw-shaped titanium implant (4.0 mm in length; 2.2 mm in diameter) was placed bilaterally. The animals were randomly assigned to group 1, control, or group 2, intermittent cigarette smoke inhalation. The animals were sacrificed after 60 days and undecalcified sections obtained. The degree of bone-to-implant contact (BIC) and the bone area (BA) within the implant threads were measured in the cortical (zone A) and cancellous bone (zone B) areas. A slight difference in the BIC was noted between the groups, but this was not statistically significant either in zone A or in zone B (Mann-Whitney test, P > 0.05). In contrast, the BA close to the implant significantly decreased in both zones for group 2 (84.73% +/- 4.77 versus 79.85% +/- 6.17, zone A in groups 1 and 2, respectively, and 32.01% +/- 6.62 versus 20.71% +/- 8.57, zone B in groups 1 and 2, respectively, P < 0.05). Within the limits of the present study, intermittent cigarette smoke inhalation may result in a poor bone quality around titanium implants inserted in rats.73982-