MALDI-TOF MS imaging of controlled release implants.

MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) imaging is used to characterize novel lipid implants allowing for controlled drug delivery. Importantly, this innovative technique provides crucial information on the inner structure of the implants before and after exposure to the release medium and does not require the addition of marker substances. Implants were prepared by extrusion at room temperature. Thus, in contrast to hot-melt extruded systems, the risks of drug inactivation and solid state transformations of the lipid matrix former are reduced. Hydrogenated/hardened soybean oil and glyceryl tristearate were studied as lipids and propranolol hydrochloride and theophylline as drugs, exhibiting significantly different solubility in water. The implants were also characterized by optical microscopy, differential scanning calorimetry, water uptake and lipid erosion studies, mathematical modeling as well as in vitro drug release measurements. Importantly, broad spectra of drug release patterns with release periods ranging from a few days up to several months could easily be provided when varying the initial drug content and type of lipid, irrespective of the type of drug. The diameter of the implants can be as small as 1mm, facilitating injection. MALDI-TOF MS imaging revealed homogeneous macroscopic drug distributions within the systems, but steep drug concentration gradients in radial and axial direction at the lower micrometer level, indicating drug- and lipid-rich domains. As the implants do not significantly swell, local irritation upon administration due to mechanical stress can be expected to be limited. Good agreement between experimentally measured and theoretically calculated drug release kinetics revealed that diffusional mass transport plays a major role for the control of drug release from this type of advanced drug delivery systems.

Indice de placa e sangramentos gengivais: a influência de ingredientes herbários / Plaque index and gingival blooding: the influence of herbal ingredients

A eficácia de ervas medicinais, tanto nos cremes dentais como nos enxaguatórios bucais, para o tratamento da placa dentária, dos sangramentos gengivais e do pH da saliva total foi investigada em um estudo simples-cego com 50 estudantes de Odontologia, com idades entre 23 e 28 anos. Durante um período de 4 semanas, 25 estudantes usaram placebo ou preparados contendo ervas medicinais. Os parâmetros medidos foram os índices aproximados de placa (API) e os índices de sangramentos gengivais (SBI). Esses índices eram determinados na mesma hora do dia (24:00 h), tendo a última alimentaçäo ocorrido pelo menos 1 hora antes. Comparados com os preparados de placebo, os ingredientes herbários reduziram significativamente tanto o API (valor inicial: 40,8 por cento; valor final: 23,9 por cento) quanto o SBI (valor inicial: 33,4 por cento; valor final: 18,6 por cento). O pH da saliva foi bastante elevado para o âmbito alcalino pela aplicaçäo dos produtos herbários, enquanto que os produtos de placebo tiveram efeito contrário. Os resultados deste estudo sugerem que os ingredientes herbários podem ser empregados como apoio à terapia das doenças periodontais e como profilaxia de rotina

Efficacy of different irrigation methods and concentrations of root canal irrigation solutions on bacteria in the root canal.

The effectiveness of two different root canal irrigating solutions, each in two different concentrations or formulations, with two different irrigation methods was compared in vitro by means of bacterial survival determinations. 75 human root canals were enlarged, sterilized and inoculated with a mixed culture of Escherichia coli and Streptococcus mutans. After inoculation, the root canals were irrigated either manually or with an ultrasonic device for equal times (20s) with the same amount (5 ml) of sodium hypochlorite (1% and 2%), Fokalhydran I and Fokalhydran II. Sodium hypochlorite (1% and 2%) was used in a 1:100 dilution. Fokalhydran I and II were used in a 1:10 dilution. In the sodium hypochlorite group, the 1% concentration applied with a syringe proved to be most effective against Escherichia coli and Streptococcus mutans. The least effective concentration and application method against both bacteria species was obtained with 2% NaOCL and ultrasonics. Against Escherichia coli and Streptococcus mutans, a significantly lower effectiveness was found with 2% NaOCL applied with ultrasonics with respect to the rest of the sodium hypochlorite group. Fokalhydran I was significantly better than Fokalhydran II against Escherichia coli. However, no significant differences could be seen against Streptococcus mutans within this group.

[The effects of herbal agents on dental plaque and sulcus bleeding index]. / Der Einfluss von pflanzlichen Wirkstoffen auf Plaqueindex und Blutungsneigung der Gingiva.

This study was designed to examine the efficacy of plant-derived active substances in a combined application of toothpaste and mouth rinse on dental plaque and sulcus bleeding index and the pH values of the saliva. 50 healthy students of dentistry without periodontal diseases took part in this study. Over a period of 4 weeks half of the group used herbs, while the other half used a placebo preparation. The data of the oral examination were always obtained at 12 a.m., with the last food intake at least 1 hour before. The results revealed a significant reduction of plaque accumulation and bleeding signs under herbal extracts in contrast to the placebo preparation. The salivary pH values were shifted to the alkaline range in the herbal extract group whereas the placebo product showed the opposite effect. Our data demonstrate the usefulness of herbal extracts as an adjunct in the treatment of periodontal disease and in a routine preventive regimen.

The influence of herbal ingredients on the plaque index and bleeding tendency of the gingiva.

The effectiveness of medicinal herbs in both a toothpaste and oral rinse on dental plaque, sulcus bleeding, and the pH of total saliva was investigated in a single-blind study on 50 dentistry students between the ages of 23 and 28 years. Over a period of 4 weeks, 25 students used either placebo or preparations containing medicinal herbs. Parameters measured were the approximal plaque index (API) and sulcus bleeding index (SBI). These were determined at the same time of day (12:00 P.M.), the last food intake having occurred at least 1 hour previously. Compared with the placebo preparations, the herbal ingredients significantly reduced both the API (initial value: 40.8%, final value: 23.9%) and the SBI (initial value: 33.4%, final value: 18.6%). The pH of the total saliva was significantly displaced into the alkaline range by the application of the herbal products, whereas the placebo products had a contrary effect. The results of this study suggest that herbal ingredients can be employed supportively in the therapy of periodontal diseases and for routine prophylaxis.

[Trace element studies on the the dental calculi of individuals from historical populations]. / Spurenelementuntersuchungen an Zahnsteinen von Individuen historischer Populationen.

In two different populations (Bavaria 6th-7th cent. A.D. and Egypt 700 B.C. till 400 A.D.) calculus was analysed in order to find hints for the nutrition of these people. All together, the concentration of 23 elements were analysed. The first dates showed that there were high significant differences in 8 elements (Al, Ba, Ca, Cr, Fe, K, Mn, Sr). The enormous variation of the element concentration as well as the huge of elements allows finally interpretations not in this state. It will be the aim of further studies.