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Analgesic efficacy of rofecoxib compared with codeine/acetaminophen using a model of acute dental pain.

OBJECTIVE: To determine analgesic efficacy of a single oral dose of rofecoxib 50 mg compared with acetaminophen/codeine 600/60 mg, we conducted a double-blind, randomized, placebo- and active-comparator-controlled, parallel-group study. STUDY DESIGN: Patients (N = 390) experiencing moderate or severe pain postextraction of 2 or more third molars, with at least 1 mandibular impaction, were randomized to placebo (n = 30), rofecoxib (n = 180), or codeine/acetaminophen 60/600 mg (n = 180). Time to confirmed perceptible pain relief, and patient evaluations of pain intensity, pain relief, and global assessments were recorded. RESULTS: For total pain relief over 6 hours (primary end point), rofecoxib was superior to codeine/acetaminophen (15.5 vs 10.7; P < .001). Rofecoxib was statistically significantly superior to codeine/acetaminophen with respect to TOPAR4, patient global assessment, peak pain relief, and duration of analgesic effect. Median onset of analgesia was similar for both drugs. The codeine/acetaminophen group had more patients with 1 or more adverse events. CONCLUSION: Rofecoxib provided superior analgesic efficacy compared with codeine/acetaminophen with fewer gastrointestinal and nervous system adverse events.

Acetaminophen↗

Palatoalveolar outcome at 18 months following simultaneous primary cleft lip repair and posterior palatoplasty.

It is frequently reported that early repair of the soft palate induces narrowing of the remaining palatal cleft and thus facilitates later hard palate closure. However, to the best of our knowledge, there have been no comparative studies to test this hypothesis. The purpose of this retrospective study was to evaluate the change of palatoalveolar morphology following primary lip repair and posterior palatoplasty. Dental plaster models of patients with complete unilateral cleft of lip and palate (UCLP) were used to measure the width of the cleft and palatal arch. Twenty-six patients received simple posterior palatoplasty (PP group) simultaneous with primary lip repair, and 20 patients did not (NPP group). The dental models included one preoperative cast at 2 months (T1) and two or three casts at 6 (T2), 12 (T3), and 18 (T4) months before final palate closure. The linear measurements performed were width of alveolar cleft (Ca); width of palatal cleft between the canines (Cc), molars (Cm), and tuberosities (Ct); the palatal arch distance between the canines (Dc); the widest distance between molars (Dm) and the tuberosities (Dt); and the palatal height between the canines (Hc) and tuberosities (Ht). The raw measurements and the calculated cleft-to-arch ratios of Cc/Dc, Cm/Dm, and Ct/Dt were compared between the two groups. The results showed gradual narrowing of the width of cleft from T1 to T4. Narrowing of alveolar cleft width (Ca) from T1 to T2 was dramatic. The palatal arch (Dc, Dm, Dt) showed no change to mild increase in width. The cleft-to-arch ratios decreased with time. The palatal height remained the same or slightly increased over time. There were no significant differences observed between the PP and NPP groups among these measurements except for the Ct and Ct/Dt at T4. In conclusion, after initial lip repair, there was a decrease of the width of cleft in patients with complete UCLP during the 18-month period, and simple posterior palatoplasty did not further narrow the cleft nor influence palatal arch development.

Chi-Square Distribution↗

A comparison of rofecoxib versus celecoxib in treating pain after dental surgery: a single-center, randomized, double-blind, placebo- and active-comparator-controlled, parallel-group, single-dose study using the dental impaction pain model.

BACKGROUND: Rofecoxib and celecoxib, selective cyclooxygenase-2 inhibitors, have analgesic efficacy similar to that of nonselective nonsteroidal anti-inflammatory drugs. OBJECTIVE: This study was designed to confirm earlier findings that the overall analgesic efficacy of rofecoxib 50 mg was superior to that of celecoxib 200 mg and to extend the comparison to include celecoxib 400 mg. METHODS: In this single-center, randomized, double-blind, placebo- and active-comparator-controlled, parallel-group, single-dose study, patients who experienced moderate or severe pain after surgical extraction of at least 2 third molars received a single oral dose of either rofecoxib 50 mg, celecoxib 400 mg, celecoxib 200 mg, ibuprofen 400 mg, or placebo. Patients recorded scores of pain intensity, pain relief, and global assessment at prespecified time intervals throughout the 24-hour period after dosing. The end points were total pain relief (TOPAR) score over 8 hours (TOPAR8; primary end point), TOPAR score over 12 hours (TOPAR12), sum of pain intensity difference (SPID) over 8 and 12 hours (SPID8 and SPID12), patient's global assessment of study drug at 8 hours, time to confirmed perceptible pain relief (ie, time to onset of analgesic effect), peak pain intensity difference (PID), peak pain relief, time to first dose of rescue medication (ie, duration of analgesic effect), and percentage of patients using rescue medication. RESULTS: A total of 482 patients (358 females, 124 males; mean age, 22.1 years) were enrolled. Rofecoxib 50 mg (n = 151 patients) demonstrated significantly greater overall analgesic efficacy compared with celecoxib 400 mg (n = 151), as measured by TOPAR8 (least squares mean [SE] 17.2 [0.8] vs 15.0 [0.8]; P < 0.05) and TOPAR12 (25.3 [1.2] vs 21.0 [1.2]; P < 0.05), as well as a significantly longer duration of analgesic effect (P < 0.05). Time to onset of analgesic effect and peak analgesic effect were similar for rofecoxib 50 mg and celecoxib 400 mg. Rofecoxib also showed significantly greater overall analgesic efficacy than did celecoxib 200 mg (n = 90), including greater TOPAR8 scores (17.2 [0.8] vs 11.5 [1.1]; P < 0.001), faster onset of analgesic effect (P < 0.001), greater peak analgesic effect (P < 0.001 for peak pain relief and peak PID), and longer duration of analgesic effect (P < 0.001). The overall analgesic efficacy of rofecoxib 50 mg was similar to that of ibuprofen 400 mg (n = 45), except that the duration of analgesic effect of rofecoxib 50 mg was significantly longer (P < 0.001). All active treatments produced significantly greater overall analgesic efficacy compared with that of placebo (P < 0.001 for all scores [TOPAR8, TOPAR12, SPID8, SPID12, and patient's global assessment] for all study drugs). The adverse-events (AE) profile was generally similar in all treatment groups. The 3 most common AEs were nausea, postextraction alveolitis, and vomiting. CONCLUSIONS: In this study, rofecoxib 50 mg provided generally superior overall analgesic efficacy compared with that of celecoxib 400 and 200 mg, including a significantly longer duration of analgesic effect. The overall analgesic efficacy of rofecoxib 50 mg was generally similar to that of ibuprofen 400 mg, except for a significantly longer duration of analgesic effect.

Adolescent↗

A randomized, double-blind, parallel-group study comparing the analgesic effect of etoricoxib to placebo, naproxen sodium, and acetaminophen with codeine using the dental impaction pain model.

OBJECTIVE: To compare the overall analgesic effect, including time to onset, peak and duration of effect for etoricoxib 120 mg, a new COX-2 selective inhibitor, in patients with acute pain to that of placebo. Naproxen sodium 550 mg and acetaminophen/codeine 600/60 mg were the active comparators. METHODS: A total of 201 patients with moderate to severe pain following surgical extraction of > or = 2 third molars, of which at least the mandibular tooth was impacted, were randomly allocated to receive single oral doses of placebo (n = 50), etoricoxib 120 mg (n = 50), naproxen sodium 550 mg (n = 51), or acetaminophen/codeine 600/60 mg (n = 50). The endpoints included total pain relief over 8 hours (TOPAR8, primary end point), sum of pain intensity difference over 8 hours, patient's global evaluation, onset, peak, and duration of analgesia. RESULTS: Etoricoxib 120 mg had a significantly greater least squares (LS) mean TOPAR8 score than placebo (20.9 vs 5.4; P < 0.001) and acetaminophen/codeine 600/60 mg (20.9 vs 11.5; P < 0.001), and a similar LS mean TOPAR8 score to naproxen sodium 550 mg (20.9 vs 21.3). All three active treatments had rapid onset of analgesia, median time approximately 30 minutes. The duration of analgesic effect, defined as median time to rescue medication use, was >24 hours for etoricoxib, 20.8 hours for naproxen sodium, 3.6 hours for acetaminophen/codeine, and 1.6 hours for placebo. DISCUSSION: Etoricoxib is a new COX-2 selective inhibitor under development for treatment of osteoarthritis, rheumatoid arthritis, and acute pain. In this study, etoricoxib 120 mg provided rapid and long-lasting pain relief to patients with moderate-to-severe postdental surgery pain. Etoricoxib was generally well tolerated.

Acetaminophen↗

Model studies on dental plaque formation: deoxyhexoses in Actinomyces viscosus.

A careful examination of two strains of Actinomyces viscosus, T14V (virulent) and T14AV (avirulent), revealed no qualitative or quantitative difference in 6-deoxyhexose content of their cell surface. For a further study of the role of these sugars in cell surface-related phenomena, the stereochemical configuration of deoxyhexoses of A. viscosus T14 was established by two complementary approaches. (i) Examination of the biosynthetic pathway was found to lead to the formation of both 6-deoxy-l-talose and 6-deoxy-l-mannose and showed no differences in the ability of either bacterial strain, A. viscosus T14V or T14AV, to produce the precursors of these cell wall components. The biosynthetic pathway for 6-deoxy-l-talose and 6-deoxy-l-mannose was found to originate from deoxy-thymidine diphosphate (dTDP)-d-glucose, which in turn is converted to dTDP-4-keto-6-deoxy-d-glucose. Epimerization at carbons 3 and 5 of the hexose moiety of dTDP-4-keto-6-deoxy-d-glucose is followed by stereospecific reduction with reduced nicotinamide adenine dinucleotide phosphate to yield dTDP-6-deoxy-l-talose and dTDP-6-deoxy-l-mannose. In cell-free extracts of both A. viscosus T14 and T14AV, an identical ratio of 6-deoxy-l-talose to 6-deoxy-l-mannose of 1:8 was produced. Known precursors for the d-isomers of the same 6-deoxyhexoses such as guanosine diphosphate-d-mannose and dTDP-d-mannose were not converted by A. viscosus T14 cell-free extracts. (ii) Isolation of 6-[U-(14)C]deoxytalose and 6-[U-(14)C]deoxymannose from both strains of A. viscosus T14 was carried out by growing cells in a medium containing d-[U-(14)C]glucose. Again no qualitative or quantitative difference was noticeable between the two strains when 6-deoxy-hexoses were released from whole cells or purified cell walls by acid hydrolysis. Radioactive 6-[U-(14)C]deoxytalose isolated from the cell surface was used in an isotope dilution experiment to establish the stereochemical configuration of this 6-deoxyhexose. The radioactive sugar was mixed with unlabeled standard d- or l-6-deoxyhexose, respectively, and conversion to the corresponding 1-phenylflavazole derivative was carried out. Recrystallization to constant specific activity identified the radioactive sugar isolated from A. viscosus to be the l-isomer. A facile synthesis of the rare sugars 6-deoxy-l-talose and 6-deoxy-d-talose is reported.

Actinomyces↗

Cells for the study of acidic dissolution in packed apatite powders as model systems for dental caries.

A number of different designs of cells have been developed for the study of dissolution processes in packed apatite powders. Basic design requirements were that no deleterious processes, such as high temperature sintering or binding agents, were involved, and that there was maximum opportunity for experimental study. One design used alternating filter paper discs and apatite layers (typically 42 mg). At the end of an experiment, the cell could be disassembled and infrared spectra and X-ray powder diffraction patterns made of individual layers. Cells without filter paper discs were also made, but terminal sampling at well-defined depths was more difficult or impossible. The cells were constructed from poly(methylmethacrylate) so the course of dissolution could be monitored by radiography. Subsurface loss of apatite was almost always seen after from 2 weeks to 8 months exposure to buffer solutions at pH 3.0-5.5. The greatest loss of apatite was typically 0.4-2 mm below the surface, which is at a larger distance than usually seen for dental enamel. This may be attributable to the low packing density (typically 35-60 vol%) found in the present systems compared with enamel.

Acids↗