When toothache results in asthma diagnosis

Local anesthetics (LA) have been used for a wide variety of procedures over the years due to their analgesic effect. These drugs have been seen to cause adverse events in the pediatric population, but an actual allergy must be in question. A case of an apparent hypersensitivity reaction to LA used in the setting of dental procedures in a 14.5-year-old girl with a forgotten history of asthma was reported and medical documentation review was performed. After treatment with LA during several dental procedures, the patient presented the shortness of breath, malaise and fainting, which then resolved spontaneously. After proper history taking, and skin and provocation tests, the patient was diagnosed with bronchial asthma and emotional sensitivity. The patient's recommendation included using an antihistamine and controlling her asthma before the use of LA, and administering the drug in a supine position. It is essential to consider all possible etiologies of an adverse event after using drugs in the pediatric population and to perform proper testing before making the diagnosis of a drug allergy.

Activation of trigeminal ganglion satellite glial cells in CFA-induced tooth pulp pain in rats

This study further investigated the mechanisms underlying the rat model of tooth pulp inflammatory pain elicited by complete Freund's adjuvant (CFA), in comparison to other pulpitis models. Pulps of the left maxillary first molars were accessed. In the CFA group, the pulps were exposed, and CFA application was followed by dental sealing. In the open group, the pulps were left exposed to the oral cavity. For the closed group, the pulps were exposed, and the teeth were immediately sealed. Naïve rats were used as negative controls. Several parameters were evaluated at 1, 2, 3 and 8 days. There was no statistical significant difference among the groups when body weight variation, food or water consumption were compared. Analysis of serum cytokines (IL-1β, TNF or IL-6) or differential blood cell counts did not reveal any evidence of systemic inflammation. The CFA group displayed a significant reduction in the locomotor activity (at 1 and 3 days), associated with an increased activation of satellite glial cells in the ipsilateral trigeminal ganglion (TG; for up to 8 days). Amygdala astrocyte activation was unaffected in any experimental groups. We provide novel evidence indicating that CFA-induced pulp inflammation impaired the locomotor activity, with persistent activation of ipsilateral TG satellite cells surrounding sensory neurons, without any evidence of systemic inflammation or amygdala astrogliosis.

Drug-induced disorders of teeth

It is essential that every health care professional who is involved with the prescription or recommendation of drugs be fully aware of any resultant disorders that may arise as a side-effect. A range of drugs can affect the teeth. In this review article, drugs that have the potential to induce changes in teeth have been classified as those leading to tooth discoloration (intrinsic and extrinsic), physical damage to tooth structure (enamel, dentin, and cementum), and alteration in tooth sensitivity.

Blink reflexes in patients with atypical odontalgia

AIMS

To use the human blink reflex (BR) to explore possible neuropathic pain mechanisms in patients with atypical odontalgia (AO).

METHODS

In 13 AO patients, the BR was elicited using a concentric electrode and recorded bilaterally with surface electromyographic (EMG) electrodes on both orbicularis oculi muscles. Electrical stimuli were applied to the skin above branches of the V1, V2, and V3 nerves and to the V branch contralateral to the painful branch. Sensory and pain thresholds were determined. The BR examination of the painful V branch was repeated during a capsaicin pain-provocation test. The data were analyzed with nonparametric statistics.

RESULTS

The BR responses (R2 and R3) evoked by stimulation of V3 were significantly smaller than the BR responses evoked by stimulation of V1 and V2 (P < .004). There were no differences in BR (R2 or R3) between the painful and nonpainful sides (P > .569), and the BR (R2 and R3) was not significantly modulated by experimental pain (P > .080). The sensory thresholds were significantly lower on the painful side compared to the nonpainful side (P = .014). The pain thresholds were not different between sides (P > .910).

CONCLUSION

No major differences between the V nociceptive pathways on the right and left sides were found in a relatively small group of AO patients. Future studies that compare BRs in AO patients and healthy volunteers are needed to provide further knowledge on the pain mechanisms in AO.

Three-week clinical trial of a 14% hydrogen-peroxide, strip-based bleaching system

This clinical trial tested the efficacy and safety of a professional strip-based whitening system (Crest Whitestrips Supreme) using the manufacturer's recommended 3-week treatment regimen. These strips have a higher concentration, but a similar amount of hydrogen peroxide relative to Crest Professional Whitestrips, because the thickness of the gel on strips is reduced. Tooth whitening was measured using the value-oriented VITA Classic Shade Guide before and after treatment. Twenty-nine subjects were treated with either Crest Whitestrips Supreme or placebo strips that did not contain hydrogen peroxide. Participants in the experimental group achieved a mean lightening of nearly eight VITA shades relative to placebo, with minimal side effects.

Clinical trial comparing two daytime hydrogen-peroxide professional vital-bleaching systems

A randomized clinical trial was conducted to compare the whitening effectiveness and tolerability of two daytime, professional, hydrogen-peroxide, vital-bleaching systems. Adults who had never bleached their teeth were randomly assigned to use either 14% hydrogen-peroxide whitening strips or a marketed 9.5% hydrogen-peroxide custom-tray-based system. Maxillary arch treatment was twice daily for 30 minutes for 9 to 21 days, depending on the labeled instructions for use. Whitening response was measured objectively as L*a*b* (which represent three-dimensional tooth color from light to dark, green to red, and blue to yellow, respectively) from digital images of the maxillary anterior teeth, while comparative at-home tolerability was assessed from bleaching tolerability severity days (BTSD) scores. A total of 31 participants aged 18 to 64 were evaluated. At the end of treatment, the adjusted mean (standard deviation [SD]) delta b* was -3.35 (0.37) for the strips and -1.67 (0.344) for the trays. Treatments differed significantly (P < .05) with respect to delta b*, as well as to delta L* and delta W* values at the end of treatment. Overall, at-home strip use was better tolerated, especially with respect to oral irritation. BTSD means (SD) were 0.09 (0.25) and 0.38 (0.49), with treatments differing significantly (P = .036), favoring the strips. This comparative research demonstrated that at the end of treatment, the 14% hydrogen-peroxide whitening strips resulted in a superior, twofold reduction in yellowness and better in-use tolerability compared to the 9.5% hydrogen-peroxide custom-tray system.

Placebo-controlled, 6-week clinical trial on the safety and efficacy of a low-gel, 14% hydrogen-peroxide whitening strip

Clinical research was conducted to evaluate the extended-use safety and efficacy of Crest Whitestrips Supreme, a low-gel (100 mg on maxillary strip), 14% hydrogen-peroxide professional tooth-whitening system. The parallel-group study was randomized, double-blind, and placebo-controlled, and involved 39 healthy adults. During the treatment phase, subjects used the investigational products twice daily (for 30 minutes each) for 6 weeks (42 days). Safety and efficacy measurements were obtained at baseline and at the completion of each 3-week treatment period. Results showed that twice-daily use of Crest Whitestrips Supreme for 3 weeks resulted in a highly significant (P < .0001) improvement in tooth color, with a mean yellowness reduction (delta b*) of -3.3 and a mean brightness improvement (delta L*) of 2.4 relative to placebo. Color improvement continued with extended strip use over 6 weeks for all parameters (P < .0005). Relative to placebo at 6 weeks, color improvement was highly significant (P < .0001), with a mean delta b* of -4.1 and a mean delta L* of 3.2. Mild and transient tooth sensitivity and oral irritation were the most common adverse events. There was no evidence of any meaningful increase in adverse events with extended treatment through 6 weeks. Twice-daily use of Crest Whitestrips Supreme resulted in a highly significant improvement in tooth color after 3 weeks, with color improvement continuing over 6 weeks.

Clinical comparison of two self-directed bleaching systems

PURPOSE

This randomized clinical trial compared the clinical efficacy and tolerability of 2 marketed self-directed vital tooth-whitening systems.

MATERIALS AND METHODS

Balancing for baseline tooth color, self-reported coffee/tea use, and age, 57 adult volunteers were randomized to either a whitening strip containing 6% hydrogen peroxide or a tray-based 10% carbamide peroxide/dentifrice/mouth rinse combination system. Following the manufacturer's directions, the strip group bleached twice daily for 30 minutes, whereas the tray group bleached twice daily for 20-30 minutes, preceded by tooth brushing with a whitening dentifrice and followed by mouth rinsing with a whitening solution. Treatment extended for 14 days, with evaluation at day 7 and again at day 14. Whitening response was measured objectively as L*a*b* from standardized digital images of maxillary anterior teeth. Tolerability was assessed by oral examination and subject interview. Efficacy comparisons were made using analysis of covariance, whereas tolerability was compared using the nonparametric Wilcoxon rank-sum test.

RESULTS

Both treatments resulted in statistically significant (P < 0.01) improvements from baseline for all color parameters. For between-group comparisons, the 6% hydrogen peroxide strips yielded a nearly 3-fold reduction in yellowness (deltab*), a nearly 2-fold improvement in lightness (deltaL*), 2.6 times greater redness reduction (deltaa*), and a more than 2-fold change in overall color (deltaE*) compared to the tray-based combination system. Between-group comparisons were statistically significant for the all color parameters at both the day 7 and day 14 evaluations (P < 0.001). In general, 7-day use of the whitening strips provided significantly greater color improvement relative to the combination dentifrice/gel/rinse system at day 14. In addition, the groups differed significantly (P < 0.05) in bleaching tolerability severity-days, with the strip system demonstrating better overall tolerability compared to the combination system.

CONCLUSIONS

The single-step 6% hydrogen peroxide strips demonstrated better overall clinical response, in terms of both tooth-whitening efficacy and tolerability, than the multiple-step tray-based combination system.

Nociceptive behaviour induced by dental application of irritants to rat incisors: a new model for tooth inflammatory pain

Animal models simulating acute human pulpitis are still lacking. The rat incisors present a particular situation where most of their innervation is considered to be unmyelinated and concentrated mainly in the tooth pulp. This study reports on a new model for dental pain induced by inflammatory agents applied to the tooth pulps of incisors. In different groups of rats, artificial crowns were fixed on the lower incisors, after cutting 1-2mm of their distal extremities. A volume of 7-10 microl of solutions of saline, capsaicin (1-10mg/ml) or formalin (2.5% or 5%) was injected in the crown cavity, and the nociceptive behaviour was quantitated following a devised scoring method of four scales. Intradental application of capsaicin produced nociceptive scores in the form of one plateau for 1-2h depending on the concentration used. Similar results were obtained with intradental application of formalin 2.5%. The one plateau of nociceptive scores obtained with formalin contrasts with the biphasic aspect of nociceptive behaviour described with the intradermal formalin test. This discrepancy could be attributed to a difference in the types of afferent fibres involved in each situation. Pretreatment with morphine (2 mg/kg) attenuated, in a naloxone-reversible manner, the nociceptive behaviour observed following intradental application of capsaicin. Pretreatment with meloxicam (a cyclo-oxygenase-2 inhibitor) exerted a less pronounced attenuation of the nociceptive scores when compared with morphine. These results provide evidence for the validity of the described model for the simulation of tooth pulp inflammatory pain in awake animals.

Neuroplasticity Induced by Tooth Pulp Stimulation in Trigeminal Subnucleus Oralis Involves NMDA Receptor Mechanisms

We have recently demonstrated that application of the mustard oil (MO), a small-fiber excitant and inflammatory irritant, to the rat maxillary molar tooth pulp induces significant increases in jaw muscle electromyographic (EMG) activity and neuroplastic changes in trigeminal (V) subnucleus caudalis. Since subnucleus oralis (Vo) as well as caudalis receives projections from molar pulp afferents and is also an integral brain stem relay of afferent input from orofacial structures, we tested whether MO application to the exposed pulp induces neuroplastic changes in oralis neurons and whether microinjection of MK-801, a noncompetitive NMDA antagonist, into the Vo influences the pulp/MO-induced neuroplastic changes in chloralose/urethan-anesthetized rats. Single neuronal activity was recorded in Vo, and neurons classified as low-threshold mechanoreceptive (LTM), wide dynamic range (WDR), nociceptive-specific (NS), deep (D), or skin/mucosa and deep (S + D). The spontaneous activity, mechanoreceptive field (RF) size, mechanical threshold, and response to suprathreshold mechanical stimuli applied to the neuronal RF were assessed prior to and throughout a 40- to 60-min period after MO application to the maxillary molar pulp. In animals pretreated with saline microinjection (0.3 μl) into the Vo, MO application to the pulp produced a significant increase in spontaneous activity, expansion of the pinch or deep RF, decrease in the mechanical threshold, and increase in response to suprathreshold mechanical stimuli of the nociceptive (WDR, NS, and S + D) neurons except for those nociceptive neurons having their RF only in the intraoral region. The pulpal application of MO did not produce any significant neuroplastic changes in LTM neurons. Furthermore, in animals pretreated with MK-801 microinjection (3 μg/0.3 μl) into the Vo, MO application to the pulp did not produce any significant changes in the RF and response properties of nociceptive neurons. In other animals pretreated with saline (0.3 μl) or MK-801 (3 μg/0.3 μl) microinjected into the Vo, mineral oil application to the pulp did not produce any significant changes in RF and response properties of nociceptive neurons. These findings indicate that the application of MO to the tooth pulp can induce significant neuroplastic changes in oralis nociceptive neurons and that central NMDA receptor mechanisms may be involved in these neuroplastic changes.

A clinical evaluation of 10 percent vs. 15 percent carbamide peroxide tooth-whitening agents

BACKGROUND

Agents with carbamide peroxide, or CP, in various concentrations are widely prescribed for at-home tooth whitening. It is not clear, however, if the more concentrated gels will whitening teeth to a greater extent, as no controlled clinical trials have been reported. The authors conducted a double-blind study of human subjects to evaluate whether a 15 percent CP tooth-whitening system was more effective than a 10 percent CP system, and to determine if tooth sensitivity increased with use of the higher concentration.

METHODS

The authors recruited 57 subjects with maxillary anterior teeth of shade A3 or darker (as gauged against a value-oriented shade guide). The subjects were 18 to 65 years of age and in good general and dental health. After matching the subjects by sex and age, the authors randomly assigned them to either a control group, which used a 10 percent CP whitening agent, or an experimental group, which used a 15 percent CP agent.

RESULTS

The results indicated that there was no significant difference in shade change between the groups after one week of treatment (t = 1.455, P = .05), but there was a significant difference at the end of the treatment period (t = 2.303, P < .05), as well as two weeks after treatment concluded (t = 2.248, P < .05). There was no significant difference in sensitivity (t = 1.399, P > .05).

CONCLUSIONS

There was a significant difference in color change between the 10 percent CP and 15 percent CP groups at the end of the study period. There was no significant difference in level of tooth sensitivity between the two groups, and the incidence was equal; there was, however, a significant difference in variability of tooth sensitivity between the two groups.

CLINICAL IMPLICATIONS

If performed under the careful guidance of a dentist, at-home whitening is an effective treatment, regardless of whether 10 percent CP or 15 percent CP is used. There may be added color change and varying sensitivity with the use of 15 percent CP.

Clinical evaluation of bleaching agents of different concentrations

OBJECTIVE

The purpose of this study was to evaluate the degree of color change, any rebound effect, and sensitivities associated with using 2 different concentrations of carbamide peroxide in vivo.

METHOD AND MATERIALS

Twenty-five subjects used 10% and 15% agents in trays for 14 days on different sides of their maxillary arches. Subjects returned in 3 days and at 1, 2, 3, and 6 weeks for evaluation of color change and rebound effect. Shade matching, photographic means, and a colorimeter were used for evaluation. Subjects self-reported gingival and tooth sensitivity on a scale of 1 (no sensitivity) to 5 (severe sensitivity).

RESULTS

After 2 weeks, delta L*, delta a*, delta b*, delta E* and delta shade guide rank means for the 10% whitening agent were 6.50, -1.37, -4.63, 8.79, and -15.40, respectively; for the 15% agent, they were 8.72, -1.63, -5.90, 11.03, and -16.59, respectively. After 6 weeks, delta L*, delta a*, delta b*, delta E*, and delta shade guide rank means for the 10% whitening agent were 3.04, -0.99, -3.19, 5.13, and -13.13, respectively; for the 15% agent, they were 3.48, -1.01, -3.60, 5.58, and -13.65, respectively. Means for gingival sensitivity were 1.18 and 1.21 for the 10% and 15% agents, respectively; means for tooth sensitivity were 1.21 and 1.26 for the 10% and 15% agents, respectively.

CONCLUSION

All 3 methods of evaluation revealed a significant difference in the tooth lightness achieved by 10% and 15% products at 2 weeks but no significant difference at 6 weeks. No statistically significant difference was found in gingival or tooth sensitivity.

Clinical trial of three 10% carbamide peroxide bleaching products

BACKGROUND

A profusion of commercial bleaching systems exists on the market today, but there are few clinical comparisons of these systems.

METHODS

In this study, three different commercial 10% carbamide peroxide bleaching systems were used by 24 patients in an overnight protocol for two weeks. Each patient used two of the bleaching products simultaneously in a side-by-side comparison.

RESULTS

The mean onset of tooth whitening was 2.4 +/- 1.7 days. Tooth sensitivity was the most frequent side effect, as 64% of the patients reported tooth sensitivity occurring after 4.8 +/- 4.1 days and lasting for 5.0 +/- 3.8 days. Although intrapatient differences were recorded for the three commercial 10% carbamide peroxide bleaching systems by the patients, there were no statistical differences in the time of onset of subjective tooth whitening and the onset, frequency and duration of tooth sensitivity among the three commercial bleaching systems when compared pairwise or independently (p < 0.05).

CONCLUSION

Selection of which bleaching product to use should be based on the concentration of the active ingredient, the viscosity of the product and other marketing features. Further research is needed to investigate the causes of tooth sensitivity and methods to reduce its severity and frequency.

Randomized double-blind placebo-controlled trial of homoeopathic 'proving' for Belladonna C30

Homoeopathic drug pictures are developed by recording the symptomatic effects of homoeopathic remedies given to healthy volunteers (a 'proving'). In a double-blind randomized controlled trial we tested the hypothesis that individuals using an infinitesimal dilution of Belladonna (thirtieth potency, C30) would record more true symptoms, on a questionnaire that contained both true and false Belladonna proving symptoms, than those receiving placebo. 60 volunteers entered the study and 47 completed data collection. We were unable to distinguish between Belladonna C30 and placebo using our primary outcome measure. For the secondary outcome measure we analysed the number of individuals who proved to the remedy according to our predefined criteria: 4 out of 19 proved in the Belladonna C30 group and 1 out of 27 in the placebo group (difference not statistically significant). This pilot study does not demonstrate a clear proving reaction for Belladonna C30 versus placebo, but indicates how the question might be further investigated.

Dental and gingival pain as side effects of niacin therapy

Two 65-year-old white men with coronary heart disease, given niacin therapy for dyslipidemia for 5 months, developed intense dental and gingival pain that was associated with increases in dose and that was relieved with discontinuance of niacin treatment. One individual who took crystalline niacin had beneficial effects on lipid levels, while the other person who took a delayed release preparation had little lipid effect. The cause of these previously unreported side effects of niacin therapy is uncertain but may be related to prostaglandin-mediated vasodilatation, hyperalgesia of sensory nerve receptors, and potentiation of inflammation in the gingiva with referral of pain to the teeth.

The effects of bleaching application time on the dental pulp

This study evaluated and compared pulpal responses of teeth exposed to a 10 percent carbamide peroxide bleaching gel using short and extended application times. Of 28 subjects, four discontinued use because of thermal sensitivity. For the remaining participants, there was no difference between the pulpal readings recorded before the use of the gel or at any point during the study.

Post-insertion sensitivity with a bonded etched cast metal prosthesis. Case report

An interesting case of post-insertion sensitivity in a patient who had an etched cast metal prosthesis (Maryland Bridge) cemented with a recently marketed resin luting agent is discussed. This case report draws attention to the fact that despite the relative conservatism and simplicity commonly associated with abutment tooth preparation for resin bonded prostheses, dentine exposure should be avoided if possible to reduce the potential for chemical irritation of the pulp by components of the resin luting system.