Cannabis sativa smoke inhalation decreases bone filling around titanium implants: a histomorphometric study in rats.

PURPOSE: Although the harmful effect of tobacco smoking on titanium implants has been documented, no studies have investigated the effects of cannabis sativa (marijuana) smoking. Thus, this study investigated whether marijuana smoke influences bone healing around titanium implants. MATERIALS: Thirty Wistar rats were used. After anesthesia, the tibiae surface was exposed and 1 screw-shaped titanium implant was placed bilaterally. The animals were randomly assigned to one of the following groups: control (n = 15) and marijuana smoke inhalation (MSI) 8 min/d (n = 15). Urine samples were obtained to detect the presence of tetra-hidro-cannabinoid. After 60 days, the animals were killed. The degree of bone-to-implant contact and the bone area within the limits of the threads of the implant were measured in the cortical (zone A) and cancellous bone (zone B). RESULTS: Tetra-hidro-cannabinoid in urine was positive only for the rats of MSI group. Intergroup analysis did not indicate differences in zone A-cortical bone (P > 0.01), however, a negative effect of marijuana smoke (MSI group) was observed in zone B-cancellous bone for bone-to-implant contact and bone area (Student's t test, P < 0.01) values. CONCLUSIONS: Considering the limitations of the present study, the deleterious impact of cannabis sativa smoke on bone healing may represent a new concern for implant success/failure.

Low- and high-yield cigarette smoke inhalation potentiates bone loss during ligature-induced periodontitis.

BACKGROUND: It is well recognized that cigarette consumption is a strong risk factor for periodontitis. Tobacco companies have developed a cigarette with low levels of toxic compounds; however, its effect on periodontium has not been investigated. The aim of this study was to verify the impact of smoke produced by low- and high-yield cigarettes on bone loss resulting from ligature-induced periodontitis. METHODS: A total of 36 male Wistar rats were used in the study. A ligature was placed around one of the mandibular first molars (ligated teeth) of each animal, and they were assigned randomly to one of three groups: group 1: control (N = 10), group 2: 30 days' inhalation of smoke produced by high-yield cigarettes (N = 13), and group 3: 30 days' inhalation of smoke produced by low-yield cigarettes (N = 13). The animals were sacrificed 30 days after ligature placement, and the specimens were processed for decalcified sections. RESULTS: Intergroup analysis of unligated teeth (without periodontal disease) did not show a significant difference regarding periodontal ligament area (2.40 +/- 0.5 mm(2), 2.72 +/- 0.7 mm(2), and 2.61 +/- 0.4 mm(2) for groups 1, 2, and 3, respectively; P >0.05). Conversely, significant differences were noted in ligated teeth (with periodontitis); bone loss was directly proportional to the level of toxic compounds in the cigarettes (5.74 +/- 0.5 mm(2), 7.40 +/- 0.50 mm(2), and 6.51 +/- 0.50 mm(2) for groups 1, 2, and 3, respectively; P <0.05). CONCLUSION: Low- and high-yield cigarettes potentiated bone loss during experimental periodontitis in a directly proportional fashion.

Escovaçäo dental associada ao gel de clorexidina: no tratamento da gengivite marginal / Marginal gingivitis treatment with tooth brushing associated with clorexidina gel

O objetivo deste estudo foi observar o efeito antimicrobiano de um gel experimental de clorhexidina a 1 por cento quando associado à escovaçäo dentária, na reduçäo da placa bacteriana supragengival e da gengivite marginal, quando comparado à um placebo. Foi realizado um estudo paralelo, duplo cego, de 21 dias de duraçäo, em 20 pacientes aleatoriamente divididos em dois grupos experimentais balanceados (teste e controle), os quais foram orientados sobre H.B e que deveriam escovar os dentes com o gel designado, duas vezes ao dia. Foram realizados os índices de placa e de sangramento gengival em períodos estabelecidos de 0, 7, 14 e 21 dias. Os resultados mostraram após 21 dias, uma reduçäo estatisticamente (p<0,05) da placa e da gengivite em ambos os grupos, sendo que os mesmos näo diferiram entre si em nenhum dos períodos avaliados. Concluiu-se que a utilizaçäo do gel de clorexidina a 1 por cento näo estaria indicada para indivíduos capazes de controlar adequadamente placa bacteriana através das instruçöes de higiene bucal e da escovaçäo