Biomedical subjects

M Daubländer

Publications and source records attributed to M Daubländer.

At least 19 recordsLinked to original sources

PubMed2002

Effect of diode laser irradiation on root surfaces in vitro.

OBJECTIVE: The objective of this study was to evaluate possible morphological alterations of root surfaces after GaAlAs-diode laser (809 nm) irradiation under standardized in vitro conditions. MATERIALS AND METHODS: Root specimens obtained from extracted periodontally diseased teeth were scaled and root planed with curettes followed by air-powder abrasive treatment prior to lasing. The variable parameters were power output (0.5-2.5 W) and exposure time (10-30 sec per specimen). Additionally, the effect of a saline solution and a human blood film on the root surface was investigated. The root segments were analyzed by means of a reflected light microscope. Photographs before and after irradiation were taken and evaluated. The scale of carbonization was quantified using a grid laid over the photographs. Specimens with distinct morphological changes were analyzed with a scanning electron microscope. RESULTS: Lasing dry specimens and specimens moistened with saline resulted in no detectable alterations, irrespective of irradiation time and power output applied. Depending on different settings, irradiation caused severe damages to the root surface when segments were covered by a thin blood film. Irradiation at a power output of 1 Watt and below had barely any negative effect on the root surface, whereas lasing at 1.5, 2.0, and 2.5 Watt resulted in partial or total carbonizations of the root samples. The angle of irradiation had a significant effect on the scale of the root surface damage (Mann-Whitney U test,p < 0.05). CONCLUSION: The diode laser may cause damage to periodontal hard tissues if irradiation parameters are not adequate.

Humans↗

PubMed2001

Effect of diode laser irradiation on the survival rate of gingival fibroblast cell cultures.

BACKGROUND AND OBJECTIVE: The present study is part of a basic research program investigating the cellular effects of the GaAlAs-diode laser with a wavelength of 810 nm on human periodontal tissues. The aim of the investigation was to evaluate the effects of the laser treatment on the survival rate of human gingival fibroblasts (HGF) in monolayer cell culture at different power settings and durations. STUDY DESIGN/MATERIALS AND METHODS: HGF were obtained from a human gingival connective tissue explant. Cells were cultured on 24-well tissue culture plates. One hundred and thirty multi well cell cultures were laser treated. The variable parameters were power output (0.5-2.5 W) and exposure time (60-240 seconds per well). The cultures were analyzed by means of trypan blue staining, and the cell numbers counted under a light microscope. Photographs before and after irradiation were taken and evaluated. RESULTS: Depending on different settings, the laser irradiation caused significant (P < 0.05, t-test) reductions of cell numbers. Exposure time was more relevant to this phenomenon than the power output. Linear regression analysis revealed no unambiguous correlation between power output and cell death, when exposure time was kept constant. CONCLUSIONS: When used for periodontal pocket decontamination, the laser beam may cause damage to collateral periodontal tissues, if the power setting and the duration of the treatment are not adequate. Further investigation, especially with regard to the effects on hard tissue and microorganisms, are needed to give a secure recommendation for irradiation parameters at pocket decontamination.

Cell Count↗

PubMed2001

Effect of diode laser irradiation on the attachment rate of periodontal ligament cells: an in vitro study.

BACKGROUND: The present study is part of a basic research program investigating the cellular effects of an 810 nm GaAlAs-diode laser on human periodontal tissues. The aim of the investigation was to evaluate the effects of laser treatment of root surface specimens on the attachment of periodontal ligament (PDL) cells in vitro. METHODS: Root specimens were prepared from periodontally diseased teeth. PDL cells were obtained from human third molar ligaments. Cells were cultured under simple, standardized, and reproducible experimental conditions. One hundred fifty root specimens were scaled and root planed with curets followed by air-powder abrasive treatment; 75 were then lased and 75 served as controls. The irradiation time was 20 seconds at a power output of 1 W. The root segments were placed into culture dishes, covered with a solution of PDL cells, and incubated for 72 hours. The specimens were then washed with phosphate buffer to remove cells not attached to the surface, and the adherent cells were stained with methylene blue. Cells were counted using a reflected light microscope and the cell density per mm2 was calculated. RESULTS: The analysis of 150 specimens revealed no significant differences between the groups (P = 0.347, Wilcoxon test). The cell numbers, however, were slightly higher on laser specimens. The mean was 66 cells/mm2 in the laser group and 63.7 cells/mm2 in the control group. CONCLUSIONS: The application of the diode laser at the parameters used did not have a substantially positive effect on the new attachment of PDL cells on the tooth specimens. It remains to be investigated whether the difference detected is really clinically relevant.

Aluminum↗

PubMed1998

[Quality of cardiopulmonary resuscitation by dentists in dental emergency care].

The crucial factor deciding the success of cardiopulmonary resuscitation is a sufficient oxygen supply. At about 4 min after cardiac arrest, cerebral death results because of hypoxia, and cardiopulmonary resuscitation has to be started regardless of the pathogenesis of the cardiac arrest. The purpose of the study was to assess the application of guidelines for cardiopulmonary resuscitation by participants at a dental surgery congress (n = 96) and to evaluate previous knowledge in cardiopulmonary resuscitation and knowledge after instruction. The present study was based on the standards and guidelines for cardiopulmonary resuscitation issued by the American Heart Association. The group was divided into four groups of doctors experienced or inexperienced in clinical emergencies or with dummies. For the study the Skillmeter-ResusciAnne (Laerdal, Stavanger, Norway) was used, which has automatic data recording. After analysis of the individual errors, the success of new instruction was assessed. Good previous knowledge was registered, particularly with respect to checking respiration and hyperextension of the head (67.7%), primary insufflation (93.8%), closed-chest cardiac massage (99%) and correct compression rate (68.4%). The participants demonstrated post-instruction improvement in all subdivisions except in the group without practice on dummies (primary insufflation: from 94.4 to 88.9%; correct order of checking consciousness and respiration, primary insufflation, the carotid pulse and closed-chest cardiac massage: from 22.2 to 5.6%). Good results with marked improvements in the second passage were achieved in checking consciousness and the carotid pulse, closed-chest cardiac massage and correct implementation of compression. The participants were, however, found to be in need of further education and training in diagnostics and certain cardiopulmonary resuscitation measures. Knowledge should be improved concerning recognition of the emergency (42.7%), checking the carotid pulse (22.9%), the correct order of primary insufflation and closed-chest cardiac massage (9.4%), correct implementation of compression (21.8%) and ventilation (36.4%), and the correct ratio of compression and ventilation (21.9%). Regular courses should be targeted at these specific aspects.

Anesthesia, Dental↗

PubMed1997

The incidence of complications associated with local anesthesia in dentistry.

Local anesthetics are frequently administered in dentistry and thus can be expected to be a major source of drug-related complications in the dental office. Additionally, the dentist will more often be confronted with the treatment of risk patients; thus, the incidence of side effects can be expected to rise. In this study, 2731 patients receiving dental anesthesia were evaluated by questionnaire for risk factors, type and dosage of local anesthetic applied, type and duration of treatment, and complications associated with the administration of the local anesthetic. Of all patients, 45.9% had at least one risk factor in their medical histories, with cardiovascular diseases and allergies being the most frequent. The overall incidence of complications was 4.5%. It was significantly higher in risk patients (5.7%) than in nonrisk patients (3.5%). The most frequently observed complications (dizziness, tachycardia, agitation, nausea, tremor) were transient in nature and did not require treatment. Severe complications (seizure, bronchospasm) occurred in only two cases (0.07%). Articaine was found to be administered in over 90% of all dental anesthesias in Germany despite the great variety of local anesthetics available. Articaine 1:100,000 caused more sympathomimetic side effects than did articaine 1:200,000. Additionally, doses of local anesthetics proved not to be strictly determined according to body weight, especially for patients weighing less than 50 kg. In summary, it can be stated that dental local anesthesia can be considered safe. Nevertheless, the incidence of complications due to dental anesthesia can be expected to be further reduced if (a) patients are routinely evaluated for risk factors with an adequate medical history prior to dental treatment, (b) doses of local anesthetics are strictly determined according to body weight, (c) anesthetics with low concentrations of epinephrine are used, and (d) the concept of a differentiated dental anesthesia is applied.

Adult↗

PubMed1996

[Movement of the temporomandibular joint during tracheal intubation].

Laryngoscopy causes temporary postoperative dysfunction of the temporomandibular joint (TMJ): during iatrogenic TMJ manipulation in anaesthetised patients, the TMJs have lost the protection afforded by the tone of the surrounding muscles. Thus far, the exact type and extent of TMJ movements have not been known. The purpose of this study was to develop a method to visualise and assess TMJ movements during intubation by means of electronic axiography, a diagnostic monitor of TMJ movements used in dentistry: registration of the hinge axis (HA) as an equivalent of the condylar paths on extra-oral sagittaly mounted, parallel plates. The HA is individually defined in each patient by the pure, rotating TMJ movement during initial mouth opening (no farward gliding of the condyles, incisor distance up to 10 mm). The parallel plates are placed in the TMJ region in the skull-mounted plate bow: both registration tips ("drawing" the HA tracings on the electronic plates) are connected to the mandible by a face bow, paraocclusally fixed to the teeth. The face bow is individually shaped for each patient to allow mask ventilation and free movement of the laryngoscope during intubation. HA tracings are registered and calculated for both sides independently every 24 ms with the SAM/Klett system and presented on sagittal and frontal projections. In the operating theatre, the active mouth-opening traces (MOT) are registered first and the passive endotracheal intubation traces (EIT) after induction of anaesthesia (same head position). With informed consent and approval by the ethics committee of the Landesärztekammer Rheinland Pfalz. 40 male patients (ASA I. Mallampati I, limb surgery) were randomly allocated to four groups (n = 10 each). OS: Oral intubation, suxamethonium (1.5 mg/ kg); OV: Oral intubation, vecuronium (0.1 mg/kg); NS: Nasal intubation, suxamethonium (1.5 mg/kg); and NV: Nasal intubation, vecuronium (0.1 mg/kg). Intubation was performed 100 s after injection of the relaxant. Pre- and postoperatively (every 24 h over 3 days, in case of positive findings longer) recorded were: active movements of the mandible (maximal mouth opening/ max. laterotrusion); dysfunction of the TMJ; and pain sensation in the TMJ (Helkimo rating). MOTs and EITs were recorded and analysed with the system described and typical EIT patterns were identified: bland, clinically uneventful intubations (n = 7), massive distraction and laterotrusion of the EIT compared to the MOT (n = 24), and blocked or limited TMJ movements resulting in intubation problems (n = 1). With the method presented, TMJ movements could be visualised during endotracheal intubation for the first time. It can be used to assess techniques, routes, and instruments for intubation as well as to evaluate potential traumatising movements during endotracheal intubation.

Adult↗

PubMed1996

[The transillumination technique. An alternative to conventional intubation?].

The technique of light-guided intubation is based on the principle that a source of light brought into the trachea results in clearly visible and defined transcutaneous illumination, while no illumination can be observed with the light source in the oesophagus (Fig. 1-7). The Trachlight is a reintroduced instrument for this alternative intubation technique. The essential developments are: a length-adjustable stylet with a removable internal metal wire, a brighter light source, a stable handle with tight fixation of the endotracheal tube, and a time-dependent warning device to avoid extended intubations. One hundred twenty patients (Mallampati I. ASA I-III) were included in the study (conventional intubation [group KL, n = 60]. Trachlight intubation [group TT, n = 60]. The goals of the investigation were to examine the handling, application, problems, limitations, and possible indications of the method. The recorded parameters were: number of intubation attempts: course and duration of intubation; complications; and difficulties. In 40 patients (20 in each group) the indication for invasive blood pressure measurement was given due to the surgical procedure, and circulatory parameters were recorded at defined moments during the intubation course. In group KL 55 patients were intubated in the attempt, 4 on the second, and 1 on the third (mean duration 23.6 +/- 10.4 s, range 12-60 s). Complications were: unilateral intubation (3 patients), bradycardia (2), asystole (1) and soft-tissue injury (1). Of the 60 patients in group TT. 54 were intubated successfully, the mean time needed being 29.9 +/- 14.8 s (range: 6-61 s). The remaining 6 were then intubated by the conventional method. Positive results in group TT included: easy handling and application, no injury to soft tissues or teeth, and invariably correct placement of the tube. Problems included: sufficient transillumination was achieved only after (entire) dimming of the room, insufficient control over the distal end of the tube due to an unfixed metal wire, unintentional switching off of the light while with-drawing the metal wire, difficulties in withdrawing the metal wire (too strong fixation), as well as disturbing effects of the warning device (blinking of the light 30 s after switching on). Reasons for the 6 intubation failures were introduction of the instrument into the oesophagus despite a supposed correct position, impossibility of correct placement in a patient with an extremely large goiter, and insufficiently clear transillumination in 3 extremely obese patients. The cardiovascular parameters showed no changes during laryngeal manipulation; a clear rise in heart rate and blood pressure was recorded, however, when the tube was inserted into the trachea. The cardiovascular parameters during conventional intubations were similar. The light-guided intubation technique can be regarded as a further alternative for airway management, due to the described improvement of the instrument. The indication for the technique is given in patients in whom no difficulty with intubation is expected, to avoid soft tissue damage and traumatising temporomandibular joint movements. Preclinical use may be limited due to environmental brightness. In patients with expected difficult airway management, fiberoptic intubation will remain the method of choice.

Esophagus↗

PubMed1995

[Analgesia-sedation for maxillo-facial surgery with midazolam-pentazocine and miazolam-ketamine. Clinical double-blind study of anxiety, analgesia, sedation and amnesia].

UNLABELLED: Ketamine and midazolam, applied as intravenous medication for conscious sedation in day-case maxillo-facial surgery, has been proven to be superior to pentazocine and midazolam concerning cardiovascular parameters and respiratory depression. The aim of this study was to evaluate the effects of low-dose ketamine/midazolam on anxiety, analgesia, amnesia and subjective feelings. METHODS. 140 out-patients (ASA I) were randomly divided into four groups. The double-blind study was prospective. CONTROL GROUP: Local anaesthesia (LA), articaine 4% plus epinephrine 1:200,000 (n = 35); test group P/M: LA, additional pentazocine 0.40 mg/kg bw and midazolam 0.075 mg/kg bw i.v. (n = 35); test group K25/M: LA, additionally ketamine 0.25 mg/kg bw and midazolam 0.075 mg/kg bw i.v. (n = 35), test group K50/M: LA, additionally ketamine 0.5 mg/kg bw and midazolam 0.075 mg/kg bw i.v. (n = 35). LA was injected 3 min after application of the systemic medication in the test groups or application of a placebo (saline 0.9%) in the control group. Three further minutes later, operation was started. For evaluation questionnaires, visual analogue scales (VAS) and the state-trait anxiety inventory (STAI) were used. For testing retrograde and anterograde amnesia, acoustic sensations were delivered before application of the systemic medication (a Christmas carol) and during operation (the German national anthem). RESULTS. The control group and the test groups were comparable with regard to biological data, duration of operation, applied dosage of local anaesthetics and actual anxiety before operation. The patients in all test groups rated intraoperative anxiety as mild, in contrast to the control group. Nearly no pain sensation during the operation was remembered in all test groups. Retrograde amnesia was not found in any group. Complete anterograde amnesia was observed in all test groups with respect to the intraoperative sensation, but even in the control group 50% of the patients did not remember having heard the national anthem. As subjective feelings negative criteria were mainly reported in the control group, where as in all test groups positive sensations dominated. Dreams were reported mostly after the higher dosage of ketamine, but no patient experienced any unpleasant dreams. The clinical assessment of the different regimes were excellent for test groups P/M and K50/M, modest for the control group and test group K25/M. Postoperatively, patients of test group P/M were remarkably sedated, but no clinically relevant sedation or motor weakness were observed in the other groups. Postoperative pain sensations were rated more intense in all test groups than in the control group. In test groups P/M and K25/M an increasing pain level was recorded during the postoperative period, with the consequence of a higher demand rate for analgesics. CONCLUSIONS. Dental surgery can be performed safely with low-dose ketamine/midazolam. Compared to pentazocine/midazolam, the higher dosage of ketamine (0.5 mg/kg bw) showed identical results intraoperatively, but was superior during the postoperative period (vigilance), and thus may represent a suitable dosage. The lower dosage of ketamine resulted in worse operating conditions, but a dosage higher than 0.5 mg/kg bw might lead to unconscious sedation and might increase the frequency of unpleasant dreams.

Adjuvants, Anesthesia↗

PubMed1992

Clinical investigation of potency and onset of different lidocaine sprays for topical anesthesia in dentistry.

The clinical effects of three lidocaine-containing solutions with and without frigen (freon-113) as a propellant, after different waiting periods, and with different dosages applied were investigated in 130 outpatients who were undergoing dental treatment in the maxilla under local anesthesia. They were divided randomly into five groups (A through E): (A) Xylocaine spray with frigen, two applications (20 mg lidocaine); (B) Xylestesin spray with frigen, two applications (14 mg lidocaine); (C) Xylestesin spray with frigen, three applications (21 mg lidocaine); (D) Xylestesin pump spray without frigen, two applications (14 mg lidocaine); and (E) no topical anesthesia. They were further divided into 12 subgroups to evaluate waiting periods between the application of the topical anesthesia and the injection (1, 2, or 3 minutes). Patients assessed the pain of the injection, intensity of numbness, and intensity of the taste on a visual analog scale; they also assessed the pain of the injection compared to former injections. Pain during injection was reduced by topical application of lidocaine. A waiting period of 2 minutes proved to be sufficient and can be justified to avoid impatience and increased numbness in patients. However, a 3-minute waiting period may be appropriate for sensitive patients. An increase in the dosage failed to show better analgesia. The pump spray without frigen proved to be effective.

Aerosols↗

PubMed1992

Effects of different lidocaine sprays for topical anesthesia on cardiovascular parameters and oxygen saturation.

The effects of three lidocaine-containing solutions with and without frigen (freon-113) as a propellant on cardiovascular parameters and oxygen saturation, after different waiting periods and with different dosages applied, were investigated in 130 outpatients undergoing dental treatment in the maxilla under local anesthesia. They were divided randomly into five groups: (A) Xylocaine spray with frigen, two applications (20 mg lidocaine); (B) Xylestesin spray with frigen, two applications (14 mg lidocaine); (C) Xylestesin spray with frigen, three applications (21 mg lidocaine); (D) Xylestesin pump spray without frigen, two applications (14 mg lidocaine); and (E) no topical anesthesia. They were further divided into 12 subgroups to evaluate the influence of waiting periods between the application of the local anesthetic and the injection (1, 2, or 3 minutes). Without topical anesthesia and after the 1-minute waiting period, cardiovascular parameters increased immediately after the injection; after 2- and 3-minute waiting periods the increases were far less pronounced. The mean oxygen saturations did not change during the observed period. The higher lidocaine dosage administered (21 mg) did not intensify the positive impact on the cardiovascular parameters compared to the lower dosage (14 mg). The new pump spray without frigen proved to be as effective as the traditional, ecologically harmful aerosol sprays.

Adult↗

PubMed1991