Prospective clinical study comparing intraligamentary anesthesia and inferior alveolar nerve block for extraction of posterior mandibular teeth.

OBJECTIVES: The aim of the study was to compare the efficacy of intraligamentary anesthesia (ILA) with conventional inferior alveolar nerve block (IANB) for extraction of mandibular posterior teeth. MATERIALS AND METHODS: In a prospective clinical trial, a total of 301 mandibular posterior teeth were extracted in 266 patients. Randomization was conducted into those who received ILA (patients n = 98; teeth n = 105) and those who received IANB (patient n = 140; teeth n = 140). Twenty-eight patients were subjected to bilateral mandibular dental extractions and received both ILA und IANB (teeth n = 56 (ILA n = 28; IANB n = 28)). The primary objective was to evaluate the differences in pain during injection, in pain during tooth extraction (numeric rating scale (NRS)), and in anesthetic quality (complete/sufficient vs. insufficient/no effect). Differences in latency time, amount of anesthetic solution, need for second injection, and duration of local numbness as well as in the incidence of dry socket were assessed. RESULTS: ILA had significant lower pain of injection (p < 0.001), shorter latency time (p < 0.001), and shorter duration of local numbness (p < 0.001) and required lesser amount of local anesthetic solution (p < 0.001) together with a similar anesthetic quality (p = 0.082) compared to IANB. Concerning pain during extraction (p = 0.211), frequency of second injection (p = 0.197), and incidence of dry socket (p = 0.178), no significant differences were detected. CONCLUSION: ILA fulfills the requirements of a minimal invasive and patient-friendly local anesthetic technique. In accordance, it represents a safe and reliable alternative to IANB for extraction of mandibular posterior teeth. CLINICAL RELEVANCE: ILA can be recommended for routine dental extractions.

Somatosensory profiles of patients with chronic myogenic temporomandibular disorders in relation to their painDETECT score.

BACKGROUND: The purpose of this study was to characterize patients with chronic temporomandibular disorders (TMD) in terms of existing hyperalgesia against cold, heat and pressure. METHODS: The extent of hyperalgesia for pressure and thermal sensation in TMD patients was determined by the use of the painDETECT questionnaire ("Is cold or heat in this area occasionally painful?" "Does slight pressure in this area, e.g., with a finger, trigger pain?") and experimental somatosensory testing against thermal and pressure stimuli (Quantitative Sensory Testing; QST). In addition, we explored psychological comorbidity among the chronic TMD patients (hospital anxiety and depression scale, HADS-D and coping strategies questionnaire, CSQ). RESULTS: Nineteen patients with chronic TMD and 38 healthy subjects participated in the study. N = 12 patients had a painDETECT score ≤ 12, n = 3 patients had a painDETECT score of 13-18 and n = 4 patients had a painDETECT score ≥ 19. TMD patients with painDETECT scores ≥19 had moderately, strong or very strong enhancement of thermal and pressure pain perception, whereas patients with painDETECT scores 13-18 and ≤ 12 responded these questions with "never", "hardly noticed" or "slightly painful" (p < 0.05-0.01). With increasing painDETECT scores we found increased hyperalgesia for pressure (p < 0.01) and thermal stimuli (p < 0.05) in QST. The patients with a painDETECT score ≥ 19 showed increased signs of anxiety (p < 0.05), depression (p < 0.01), praying and hoping (p < 0.05). CONCLUSION: The present study has shown that the PainDETECT questionnaire can be a helpful additional diagnostic tool. Together with QST, the PainDETECT questionnaire detected hyperalgesia for pressure and thermal sensation. Therefore the PainDETECT questionnaire is helpful to decide which TMD patients should undergo QST.

Movement control during aspiration with different injection systems via video monitoring-an in vitro model.

OBJECTIVES: The aim of the present study was an evaluation of movement during double aspiration by different manual syringes and one computer-controlled local anesthesia delivery system (C-CLAD). MATERIALS AND METHODS: With five different devices (two disposable syringes (2, 5 ml), two aspirating syringes (active, passive), one C-CLAD), simulation of double aspiration in a phantom model was conducted. Two experienced and two inexperienced test persons carried out double aspiration with the injection systems at the right and left phantom mandibles in three different inclination angles (n = 24 × 5 × 2 for each system). 3D divergences of the needle between aspiration procedures (mm) were measured with two video cameras. RESULTS: An average movement for the 2-ml disposal syringe of 2.85 mm (SD 1.63), for the 5 ml syringe of 2.36 mm (SD 0.86), for the active-aspirating syringe of 2.45 mm (SD 0.9), for the passive-aspirating syringe of 2.01 mm (SD 0.7), and for the C-CLAD, an average movement of 0.91 mm (SD 0.63) was seen. The movement was significantly less for the C-CLAD compared to the other systems (p < 0.001). The movement of the needle in the soft tissue was significantly less for the C-CLAD compared to the other systems (p < 0.001). CONCLUSIONS: A difference in involuntary movement of the syringe could be seen in comparison between manual and C-CLAD systems. Launching the aspiration by a foot pedal in computer-assisted anesthesia leads to a minor movement. CLINICAL RELEVANCE: To solve the problem of movement during aspiration with possibly increased false-negative results, a C-CLAD seems to be favorable.

Comparison of anesthetic efficacy of 2 and 4 % articaine in inferior alveolar nerve block for tooth extraction-a double-blinded randomized clinical trial.

OBJECTIVES: The purpose of this clinical prospective, randomized, double-blind trial was to compare the anesthetic efficacy of 2 % articaine and 4 % articaine in inferior alveolar nerve block anesthesia for extraction of mandibular teeth. MATERIALS AND METHODS: In 95 patients, 105 lower molar and premolar teeth were extracted after intraoral inferior alveolar nerve block. In 53 cases, 2 % articaine (group I) and, in 52 cases, 4 % articaine (group II) was administered. The primary objective was to analyze the differences of anesthetic effects between the two groups (complete/sufficient vs. insufficient/none). Furthermore, differences in pulpal anesthesia (onset and depth, examined with pulp vitality tester (min)), as well as in length of soft tissue anesthesia (min), were evaluated. Additionally, the need of a second injection, pain while injecting (numeric rating scale (NRS)), pain during treatment (NRS), pain after treatment (NRS), and other possible complications (excessive pain, bleeding events, prolonged deafness) were analyzed. RESULTS: Anesthesia was sufficient for dental extractions in both groups without significant differences (p = 0.201). The onset of anesthesia did not differ significantly (p = 0.297). A significantly shorter duration of soft tissue anesthesia was seen in group I (2.9 vs. 4 h; p < 0.001). There was no significant difference in the need for a second injection (p = 0.359), in injection pain (p = 0.386), as well as in pain during (p = 0.287) or after treatment (p = 0.121). In both groups, no complications were seen. CONCLUSIONS: The local anesthetic effect of the 4 % articaine solution is not significantly better when compared to 2 % articaine. CLINICAL RELEVANCE: For mandibular tooth extraction, articaine 2 % may be used as alternative as well.

Clinical efficacy of a computerised device (STA™) and a pressure syringe (VarioJect INTRA™) for intraligamentary anaesthesia.

INTRODUCTION: To evaluate the impact of experience whilst using different devices for intraligamentary anaesthesia, dental students tested clinical anaesthetic efficacy of a mechanical (PDL-S) and a computer-controlled (CCLAD) application system in restorative patients. MATERIAL AND METHODS: In a prospective study, 41 Patients in need of restorative treatment in lower posterior mandible were randomised into three groups (PDL-S: teeth n = 22; CCLAD: teeth n = 20; inferior alveolar nerve block (IANB): teeth n = 20). Dental last year students conducted anaesthesia and dental treatment. Primary objectives were differences in pain during treatment [numeric rating scale (NRS)] as well as in anaesthetic efficacy (complete/sufficient vs. insufficient/no effect) between PDL-S and CCLAD. Pain of injection, need for second injections, amount of anaesthetic solution and duration of local numbness were assessed. IANB as gold standard was compared to each system descriptively. RESULTS: PDL-S had a significant lower pain during treatment (P = 0.017) but a similar anaesthetic efficacy (P = 0.175) compared to the CCLAD system. Concerning pain of injection (P = 0.42), quantity of second injections (P = 0.232), amount of used solution (P = 0.073) as well as duration of local numbness (P = 0.253), no differences were seen. When comparing both periodontal ligament injection (PDL)-systems with IANB, pain rating was higher when using CCLAD. Injection pain, amount of used solution as well as soft tissue anaesthesia was less for PDL-S and CCLAD. DISCUSSION: Both PDL techniques showed a good success for dental routine treatments. Although, compared to the mechanic device, the CCLAD system might need more clinical daily experience. CONCLUSION: We recommend including specific trainings in intraligamentary anaesthesia in the dental curriculum.

Comparative clinical evaluation of different epinephrine concentrations in 4% articaine for dental local infiltration anesthesia.

OBJECTIVES: The aims of this study were to compare and evaluate the clinical anesthetic efficacy of five 4% articaine solutions with and without epinephrine in pulpal anesthesia after infiltration. MATERIALS AND METHODS: In a randomized, double-blinded, crossover study, ten volunteers received local anesthesia infiltration in the maxillary right central incisor with five different solutions (4% articaine + epinephrine 1:100,000, + epinephrine 1:200,000, + epinephrine 1:300,000, + epinephrine 1:400,000, without epinephrine). Electronic pulp tester was used to calculate the onset, utilization time, time to recede, and the surface integral under the time-effect curve. Additionally, cardiovascular parameters and post-experimental soft tissue anesthesia were examined. RESULTS: Onset as well as time to recede was not influenced by the epinephrine concentration. When using the epinephrine-free agent, time to recede was significantly shorter. Upon decreasing epinephrine concentration, duration of pulpal anesthesia and total anesthetic efficacy declined. The shortest time of anesthesia and lowest anesthetic efficacy were seen for the solution without epinephrine. No association was found between the local anesthetic drug and cardiovascular parameters. Soft tissue anesthesia was significantly shorter without epinephrine. CONCLUSIONS: This study shows the substantial benefits of vasoconstrictors in dental infiltration anesthesia. These findings were reflected by means of prolonged and deeper therapeutic effect in a dose-dependent manner. CLINICAL RELEVANCE: Even when utilizing agents with reduced amount of epinephrine, a safe anesthesia is possible. The epinephrine-free solutions resulted in a distinct limitation of utilization time and efficacy.

Periodontal intraligament injection as alternative to inferior alveolar nerve block--meta-analysis of the literature from 1979 to 2012.

OBJECTIVES: In a first meta-analysis, inferior alveolar nerve block (IANB) and periodontal intraligamentary injection anesthesia (ILA) were compared with focus on the failure rate of local anesthesia, pain during injection, additional injections, cardiovascular disturbances (CVD), and method-inherent differences (unwanted side effects, latency time, amount of anesthetic solution, duration of anesthesia) in adult patients. MATERIALS AND METHODS: Prospective and retrospective studies with clinical comparison of both injection techniques considering the relevant outcome parameters in adult patients from 1979 to 2012 were included. A specific tool for assessing risk of bias in each included study was adopted. Data were assessed for methodological reliability and extracted and supplemented by sensitivity analysis by two independent reviewers. RESULTS: Seven studies were included [evidence grade Ib (n=1), IIb (n=3), and III (n=3)]. For other parameter than CVD, the significant heterogeneity of the random effects did not allow the reporting of pooled summary effect estimates. CVD were found significantly more often after IANB [odds ratio (OR): 0.12 (0.02-0.69)]. Further analysis revealed less injection pain in cases of ILA [OR: 0.32 (0.1-1)]. For failure rates as well as for needed additional injections, no significant differences were detected. IANB showed a latency of >3 min, whereas ILA had nearly none. The effect of IANB is longer than for ILA. CONCLUSIONS: Methodological and reporting flaws were consistently observed in the included articles. Except for CVD, it could not be shown that ILA is neither superior nor inferior compared to IANB. CLINICAL RELEVANCE: IANB as "gold standard" for routine dental treatments should be discussed.

Influence of needle bevel design on injection pain and needle deformation in dental local infiltration anaesthesia - randomized clinical trial.

The aims of this in vivo study were to evaluate the impact of needle bevel design on patients' pain perception and the mechanical deformation of the needle tip after the injection. In a prospective single-blinded trial, 150 patients received conventional infiltration anaesthesia for dental treatment by one examiner. Patients were randomized for one out of three different needle bevel types (scalpel-designed bevel needle (SB), n=50; triple bevel needle (TB), n=50; regular bevel needle (RB), n=50). Subjects' self-reported injection pain perception was evaluated using a numeric rating scale (NRS). For each needle tip, deformations after single use were measured using SEM. A significant lower injection pain level was found in SB (mean 2.1±1.2) than in TB (mean 3.5±1.6;) and RB (mean 3.4±1.0; all P<0.001). A needle deformation was detected in about 97.3% of all needles (SB 50/50, TB 50/50, and RB: 46/50). A higher number of barbs were found in SB (29/50) versus TB (17/50) and RB (19/50). For dental local infiltration anaesthesia, injection needles with a scalpel-designed bevel demonstrated significantly less injection pain. Needle tip deflections after anaesthetic agent infiltration, especially barbed hooks on the non-cutting edge may result in greater soft tissue trauma.

Best clinical practice guidance for local analgesia in paediatric dentistry: an EAPD policy document.

BACKGROUND: The European Academy of Paediatric Dentistry (EAPD) proposes this best-practice guidance to help practitioners to decide when and how to use local analgesia to control pain in children, adolescents, and medically compromised individuals during the delivery of oral health care. METHODS: A search of different databases was conducted using all terms relevant to the subject. Relevant papers were identified after a review of their titles, abstracts or full papers. Three workshops were held during the corresponding EAPD interim seminar in Torino (Italy) in 2017. Several statements were agreed upon and, furthermore, knowledge gaps were identified. RESULTS: An important outcome was that when local analgesia administered appropriately-correct choice of agent(s) and dosage, proper route of administration-it is, firstly, clinically effective for pain-control in treating children and, secondly, it carries a very low risk of morbidity including adverse or side-effects. Furthermore, several gaps in knowledge were identified during the workshop which indicates future research needs. Most importantly it remains unsatisfactory that in several European countries the most frequently used injectable local analgesic agent, articaine, is not approved for usage in children below the age of 4 years. CONCLUSION: When considering the dental demand to treat vulnerable (medically compromised) children and adolescents in a safe, painless, less-invasive and effective way, there seems to be an urgent need to close these gaps in knowledge.

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.

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.

Epinephrine-reduced articaine solution (1:400,000) in paediatric dentistry: a multicentre non-interventional clinical trial.

AIM: In paediatric dentistry, epinephrine may contribute to systemic and local side-effects. On the other hand it is necessary to provide good and safe local analgesia. Therefore, an articaine solution with reduced epinephrine concentration was tested in a clinical setting. METHODS: In a non-interventional clinical study, dental treatment was performed in children and adolescents (4-17 years). For local analgesia, articaine 4 % plus epinephrine 1:400,000 was used in the technique chosen by the dentist. Efficacy and tolerance as well as duration of soft tissue analgesia and side-effects were evaluated. RESULTS: 999 patients (50.5 % male, 49.5 % female) with a mean age of 7.9 (SD 2.34) years were treated. Two hundred seventy six patients (27.6 %) received sedation prior to treatment. The mean treatment time was 15 min (SD 10). In 93.5 % of cases, initial local analgesia was sufficient to perform the planned treatment. In 99 % of cases (n = 989) the planned treatment could be completed. A second injection was necessary in 6.5 % of cases. A mean duration of soft tissue analgesia of 2.19 h (SD 1.01) was seen. Slight side-effects occurred in 3.1 % of subjects. CONCLUSIONS: Due to high efficacy, tolerance and safety, the articaine 4 % solution with the reduced epinephrine concentration (1:400,000) was a safe and suitable drug for paediatric routine treatment.

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.

[O.15 mg Intrathecal buprenorphine applied for postoperative analgesia. A clinical double-blind study]. / Buprenorphin 0.15 mg intrathekal zur postoperativen Analgesie. Eine klinische Doppelblindstudie.

In a double-blind, randomized study of 29 patients who underwent orthopedic procedures we studied the additional effect of intrathecal buprenorphine on isobaricpinal anesthesia and postoperative analgesia. The injections were 20 mg tetracaine (19 patients) or 20 mg tetracaine plus 0.15 mg buprenorphine (10 patients). In both groups the drugs were contained within a total volume of 4 ml cerebrospinal fluid. Progression and regression of the sensory blockade of spinal anesthesia were estimated with pinprick; the motor blockade was judged by the Bromage scheme. Postoperative pain was evaluated by the patients using an analogue scale after Scott and Huskisson. Arterial blood gases, respiratory rate, blood pressure, and heart rate were measured and other side-effects determined. Both groups were comparable in age, body weight, height and duration of operation (Table 1). The addition of buprenorphine elevated the sensory blockade by three segments both during spread and regression of anesthesia (Figs. 1, 2). Postoperative analgesia was better up to 8 h after injection (p less than 0.05), after 8 h pain levels were equal in test and control groups (Fig. 3). After buprenorphine patients became aware of pain sensation 13 h after injection; in the control group the pain-free interval lasted only 9 h (p greater than 0.05). There were no differences in the need for postoperative analgesics between both groups. The respiratory rate was lower during the whole period of observation (p less than 0.05). The mean values for PaCO2, pH and BE were similar in both groups (Fig. 4). PaO2 was elevated in the buprenorphine group. There was no essential alteration of blood pressure after buprenorphine. The pulse rate, however, was slightly diminished.(ABSTRACT TRUNCATED AT 250 WORDS)

[Analgesia-sedation for maxillo-facial surgery with midazolam-pentazocine and miazolam-ketamine. Clinical double-blind study of anxiety, analgesia, sedation and amnesia]. / Analgosedierungsverfahren für zahnärztlich-chirurgische Eingriffe mit Midazolam/Pentazocin und Midazolam/Ketamin. Klinische Doppelblindstudie zu Anxiolyse, Analgesie, Sedierung und Amnesie.

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.

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.

[Movement of the temporomandibular joint during tracheal intubation]. / Bewegungen der Kietergelenke während der endotrachealen Intuoation.

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.