Aspirin-induced post-gingivectomy haemorrhage: a timely reminder

A case report is described of significant aspirin-induced haemorrhage following a gingivectory procedure in an organ transplant patient. Aspirin-induced platelet impairment secondary to low-dose aspirin was implicated as the cause of the haemorrhage. Haemostasis was eventually achieved after platelet transfusion. The case illustrates the problems that can arise when carrying out gingival surgery on patients medicated with low-dose aspirin.

Determinants of gingival overgrowth severity in organ transplant patients. An examination of the rôle of HLA phenotype

The role of HLA phenotype as a risk factor for drug-induced gingival overgrowth was investigated in a cohort of 172 transplant recipients. Clinically significant overgrowth warranting surgical correction was observed in 72 patients (42%). Using stepwise regression modelling, 6 clinical parameters were identified as significant risk factors for the severity of gingival overgrowth. These were; age, sex, creatinine plasma level, duration of therapy, papilla bleeding index and concomitant medication with a calcium channel blocking drug. 3 HLA alleles were also identified as risk factors when adjusted for other clinically significant risk factors (HLA -DR2, A24, B37). However, when the p-values for the HLA variables were corrected to compensate for the use of multiple significance testing, only HLA-B37 remained statistically significant at the 5% level. Organ transplant patients are at risk of developing gingival overgrowth, with approximately 25% medicated with cyclosporin alone requiring corrective gingival surgery. This figure more than doubles in patients concomitantly medicated with a calcium blocking drug. The data at present available would suggest that the severity of gingival overgrowth is also significantly associated with the HLA-B37 phenotype.

Plasma and saliva concentrations of phenytoin and 5-(4-hydroxyphenyl)-5-phenylhydantoin in relation to the incidence and severity of phenytoin-induced gingival overgrowth in epileptic patients

This study examined the relationships between plasma and saliva concentrations of phenytoin and 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH), the major metabolite of phenytoin in man, and the prevalence and severity of gingival overgrowth. Thirty-six adult epileptic patients who had been receiving phenytoin for greater than 6 months without a recent change in dosage were assessed for signs of periodontal disease and gingival overgrowth. Plasma and saliva samples were analyzed by high performance liquid chromatography for the determination of phenytoin and HPPH concentrations. Seventeen patients demonstrated clinically significant gingival over-growth (responders; overgrowth index > or = 30%). There were significant correlations between the gingival overgrowth index and both the papillary bleeding index (r = 0.495; P < 0.005) and probing depth (r = 0.632; P < 0.005). The plaque index correlated with the papillary bleeding index (r = 0.420; P < 0.05) and the probing depth (r = 0.301; P < 0.005), but not with the gingival overgrowth index. The extent of gingival overgrowth did not correlate significantly with either plasma or saliva concentrations of phenytoin or HPPH. Mean plasma and saliva concentrations of phenytoin and HPPH did not differ significantly between non-responders and responders, nor did the mean plaque index. The mean papillary bleeding index (32.5 +/- 21.2 vs. 63.8 +/- 37.7; P < 0.01) and mean probing depth (12.4 +/- 14.4% vs. 35.9 +/- 25.3%; P < 0.02) were significantly greater in the responders. This study found no evidence of a relationship between phenytoin or HPPH concentrations in plasma or saliva and the extent, or prevalence of phenytoin-induced gingival overgrowth. Further studies with larger populations may be necessary to establish the relationship, if any, between phenytoin or HPPH levels and gingival overgrowth.

The efficacy of ketoprofen and paracetamol (acetaminophen) in postoperative pain after third molar surgery

1. A placebo-controlled, double-blind, randomized trial was carried out to evaluate the efficacy of single doses of racemic ketoprofen 12.5 and 25 mg and paracetamol 500 and 1000 mg in patients with post-operative pain after third molar surgery over a 6 h investigation period. 2. Outcome variables included overall pain scores (AUC(0,360 min), maximum pain relief, pain relief at 1 h after dosage and the number of patients taking escape analgesics. 3. Overall pain scores (AUC(0,360 min) were significantly lower for all active treatments when compared to placebo (P < 0.01). 4. Both ketoprofen treatments and patients treated with paracetamol 1000 mg reported significantly greater pain relief (P < 0.01) and a later time to taking escape analgesics (P < 0.01) than patients medicated with placebo. 5. At 1 h after dosage, pain scores were significantly less (P < 0.01) after both doses of ketoprofen when compared with placebo. 6. Single doses of ketoprofen 12.5 and 25 mg, together with paracetamol 1000 mg are effective analgesics for treating post-operative pain after third molar surgery. These treatments provide up to 4 h of pain relief after this surgical procedure.

Automated gas chromatographic assay for amlodipine in plasma and gingival crevicular fluid

This paper describes an automated capillary gas chromatographic method for the determination of amlodipine in plasma, and in sub-microlitre volumes of gingival crevicular fluid (GCF), in order to assess if amlodipine is present in GCF under conditions of gingival overgrowth, as has been shown for nifedipine, another dihydropyridine drug. Liquid-liquid extraction followed by derivatisation was employed to isolate amlodipine and render it suitable for gas chromatography. Amlodipine was analysed in plasma and GCF of four patients undergoing amlodipine therapy for cardiovascular disorders, three of whom had significant gingival overgrowth. Amlodipine was detected in the plasma of all patients and in massive concentrations in the GCF of those patients with overgrowth, 23- to 290-fold greater than in their plasma. Like nifedipine, amlodipine sequestration into GCF appears to be linked with gingival overgrowth.

The distribution of gingival overgrowth in organ transplant patients

The distribution of gingival overgrowth was investigated in a cohort of organ transplant patients, who were medicated with cyclosporin or the combination of cyclosporin and a calcium channel blocking drug. Gingival overgrowth scores were significantly higher at buccal sites than lingual-palatally (p < 0.0001). There was no significant difference between upper and lower overgrowth scores (p = 0.88). The most severe overgrowth was seen in the canine region. Overgrowth between the central incisors was significantly less than in the canine region (p > or = 0.044) and was similar to that in the molar and premolar region. Although raised overgrowth scores were associated with increased levels of plaque and gingival inflammation, the distribution could not be explained by this observation.

The pathogenesis of drug-induced gingival overgrowth

Gingival overgrowth is a well-documented unwanted effect, associated with phenytoin, cyclosporin, and the calcium channel blockers. The pathogenesis of drug-induced gingival overgrowth is uncertain, and there appears to be no unifying hypothesis that links together the 3 commonly implicated drugs. In this review, we consider a multifactorial model which expands on the interaction between drug and/or metabolite, with the gingival fibroblasts. Factors which impact upon this model include age, genetic predisposition, pharmacokinetic variables, plaque-induced inflammatory and immunological changes and activation of growth factors. Of these, genetic factors which give rise to fibroblast heterogeneity, gingival inflammation, and pharmacokinetic variables appear to be significant in the expression of gingival overgrowth. A more thorough understanding of the pathogenesis of this unwanted effect will hopefully elucidate appropriate mechanisms for its control.

Evaluation of different doses of soluble ibuprofen and ibuprofen tablets in postoperative dental pain

The object of the study was to assess the comparative efficacy of three single doses (200, 400, 600 mg) of soluble ibuprofen and ibuprofen tablets after third molar surgery in 148 patients and aged 18-40 years. Outcome was measured by overall assessment of pain (AUC360) assessed from serial visual analogue scales, the number of patients taking additional analgesic and by overall assessment of medication evaluated on a five-point categorical scale. Over the 6-hour investigation period all the ibuprofen treatments with the exception of ibuprofen tablets 200 mg resulted in significantly less pain (p < 0.05) than placebo treatment. A large number of patients required additional analgesia during the investigation period, but the time to taking it was significantly earlier in the placebo group. No significant dose response (p > 0.05) was observed for either ibuprofen preparations assessed by the outcome variable of overall pain experience (AUC360) or time to additional analgesia. There was no significant difference in pain scores or time to taking additional analgesics between the respective doses of soluble and tablet formulations of ibuprofen. Both soluble and tablet formulations of ibuprofen provide effective pain control in the early postoperative period after removal of impacted third molars. There is little analgesic advantage in increasing the dose to 600 mg and only minimal benefit from using a soluble formulation of the drug.

The pharmacokinetics of phenytoin in gingival crevicular fluid and plasma in relation to gingival overgrowth

The aim of this study was to determine whether phenytoin (PHT) could be detected in gingival crevicular fluid (GCF), and to relate its concentration to both plasma level and degree of gingival overgrowth. 23 patients medicated with phenytoin for at least 6 months were clinically examined for signs of periodontal disease and gingival overgrowth. 12 patients out of these demonstrated clinically significant overgrowth and their plaque scores and gingival inflammation were greater than for the non-overgrowth group (p < 0.001). Phenytoin concentrations were determined by high performance liquid chromatography, and was detected in GCF. There was a significant correlation between the GCF and plasma phenytoin concentrations (p < 0.05), but it was not related to the extent of gingival overgrowth. Inflammation increased the GCF volume, but was not a determinant of GCF phenytoin concentration. It is concluded that effusion of phenytoin into GCF is regulated by the plasma levels of the drug, but its concentration in GCF is not related to the incidence of gingival overgrowth.

Gingival overgrowth in paediatric cardiac transplant patients: a study of 19 patients aged between 2 and 16 years

It is well established that both cyclosporin and nifedipine are associated with gingival overgrowth. However, there is little information on the prevalence of this undesirable effect in paediatric patients. The present study investigated gingival overgrowth in 19 cardiac transplant patients aged 2 years 8 months to 16 years 3 months (1.5-8.5 years post-transplant) and related such changes to variables of daily cyclosporin dosage, trough blood cyclosporin concentration and daily nifedipine dosage. Ten patients showed clinically significant gingival overgrowth and nine relatively minor overgrowth; there was no significant difference between the two groups with respect to age, length of time post-transplant, cyclosporin dosage, whole blood concentration of cyclosporin or intake of nifedipine. The expression of gingival changes therefore did not relate to any drug variable in this group of subjects.

Effects of peripherally and centrally acting analgesics on somato-sensory evoked potentials

1. The effects of aspirin 1000 mg, paracetamol 1000 mg, codeine 60 mg on somatosensory evoked potentials (SEPs) were measured in a four-way cross-over study. 2. SEPs were elicited by electrical stimulation of the skin overlying the digital nerve at intensities close to pain threshold. 3. Amplitudes and latencies of both early and late SEPs were recorded, as well as first sensory threshold and subjective pain threshold. 4. None of the study medications affected the amplitude or latency of the late SEP components (100-250 ms post-stimulus). The amplitude of early components (15-30 ms post-stimulus) was also unaffected, but aspirin shortened the latency 30 min after ingestion. 5. Sensory detection and pain threshold to electrical skin stimulation were also unaffected by any of the study medications despite subjective central effects with codeine.

Iatrogenic gingival overgrowth in cardiac transplantation

It is well established that both cyclosporin and nifedipine are associated with gingival overgrowth. Although both drugs are widely used in the management of organ transplant patients, there is little information on the prevalence and severity of this unwanted effect in cardiac transplant patients. This study evaluated the gingival health of 94 dentate cardiac transplant patients, all of whom were medicated with cyclosporin as a component of their immunosuppressive therapy. Sixty-three (63) of the patients were also medicated with nifedipine. Significantly higher gingival overgrowth scores (P < 0.0001) and periodontal probing depths (P = 0.001) were observed in patients medicated with the combination of cyclosporin and nifedipine than those medicated with cyclosporin alone. Likewise, there was a significantly greater need to carry out gingival surgery on patients taking the combination (62%), than those medicated with cyclosporin alone (25.8%) (P = 0.001). Patient's age, sex, duration of therapy, gingival bleeding index, and nifedipine therapy were important determinants for both the expression of gingival overgrowth and the need for surgery. Significant sequestration of nifedipine in the gingival crevicular fluid (GCF) was observed. The concentration of nifedipine in GCF did not relate to either the gingival changes or plasma concentration of the drug. Cardiac transplant patients are at risk of developing gingival overgrowth and approximately 50% require surgical intervention. This risk increases significantly when patients are medicated concomitantly with nifedipine.

Periodontal variables affecting nifedipine sequestration in gingival crevicular fluid

We previously demonstrated the sequestration of nifedipine in gingival crevicular fluid (GCF), especially in patients exhibiting significant gingival overgrowth. The aim of the present study is to determine the role of site specific periodontal factors in this phenomenon. 10 adult patients exhibiting nifedipine induced gingival overgrowth were studied. In each patient GCF was harvested from two sites that demonstrated inflammation and increased probing depth as well as from two clinically healthy sites. The concentration of nifedipine was determined using gas chromatography. Drug concentrations were significantly increased in the presence of inflammation (p = 0.004) and plaque (p = 0.029) whilst increased probing depths and gingival overgrowth were not significantly related to drug sequestration. We can conclude that inflammatory changes in gingival tissues appear to be a significant determinant for the sequestration of nifedipine in the GCF.

Pharmacological control of periodontal disease. II. Antimicrobial agents

Antimicrobial agents are of value in the management of certain types of periodontal disease, notably early onset, juvenile and refractory periodontitis. The diagnosis of these conditions is often made on clinical grounds but microbial sampling of the pocket flora is of value in determining the type of antimicrobial therapy. Routine systemic use of these drugs in the management of chronic adult periodontitis is contraindicated, and is no substitute for root surface debridement and thorough supragingival plaque control. Tetracyclines and metronidazole are the agents most frequently used in the management of periodontal disease. Both drugs can be given systemically or applied topically into the periodontal pocket. The latter route is preferred since the dose is reduced considerably, but the local tissue concentration is increased. The efficacy of local drug delivery is dependent upon the release kinetics of the drug from the delivery vehicle. Although local application can be time consuming, it reduces the risk of adverse reactions and drug interactions. The tetracyclines have the additional advantage of inhibiting collagenases. This property may facilitate repair and new attachment formation. Systemic metronidazole appears to be useful as an adjunct to conventional periodontal therapy. The combination of metronidazole 250 mg and amoxycillin 375 mg has been shown to be effective in the treatment of refractory periodontitis, including cases which are resistant to tetracycline. Clindamycin has also been used in the management of refractory periodontitis, but the unwanted effects of this drug must limit its systemic use for this purpose.

Tetracyclines in the management of periodontal diseases. A review

Periodontal diseases essentially comprise a group of oral infections whose primary aetiological factor is dental plaque. Removal of the cause (and its effects) is the primary aim of both non-surgical and surgical treatment regimens, although the infective nature of the diseases has led to the widespread use of antimicrobials as an adjunct to mechanical debridement. The tetracyclines are primarily bacteriostatic agents that are effective against many Gram-negative species including putative periodontopathogens such as Actinobacillus actinomycetemcomitans (A.a.). The proven efficacy of this group of drugs in the management of periodontal diseases may be related not only to their antibacterial actions, but to a number of additional properties that have been recently identified. These include collagenase inhibition, anti-inflammatory actions, inhibition of bone resorption and their ability to promote the attachment of fibroblasts to root surfaces. Consequently, tetracyclines have also been used as an adjunct to bone grafting in periodontal defects, and as agents for 'conditioning' root surfaces to enhance the regeneration of periodontal tissues. When tetracyclines are taken orally, consideration must be given both to the potential unwanted effects and to interactions with other drugs that are taken concurrently. Such problems are minimised however, when the drugs are incorporated into controlled, slow-release formulations which are currently being researched and marketed for intra-oral use.

Pharmacological control of periodontal disease. I. Antiplaque agents

Inhibition of the development of dental plaque remains one of the primary aims of periodontal care. Many patients, however, are unable to master completely the mechanical methods of plaque control and for this reason, considerable research efforts have been directed towards the development and use of chemical agents to inhibit the growth of plaque. This first of two articles, therefore, examines the pharmacological properties and efficacy of commercially available antiplaque agents. We have also summarized the findings of some of the major clinical trials that have provided the scientific basis for the introduction of these agents for the management of gingival inflammation.

The periodontal problems and management of the renal transplant patient

This review considers the periodontal problems of renal transplant patients with particular reference to their drug therapy and the pretransplant uremia. It would appear that either disease- or drug-induced immunosuppression affords the renal transplant patient a degree of "protection" against periodontal breakdown. However, of more significance to the periodontologist is the problem of drug-induced gingival overgrowth with reference to both cyclosporin and nifedipine. Approximately 30% of dentate renal transplant patients medicated with cyclosporin alone experience significant gingival overgrowth which requires surgical excision. This figure increases to 40% when patients are medicated with both drugs. The pathogenesis of this unwanted effect is uncertain and the relationship between the expression of gingival overgrowth and various periodontal or pharmacokinetic variables remains a contentious issue. Clinical measures to prevent the occurrence of either cyclosporin- or nifedipine-induced gingival overgrowth are unsatisfactory.

Oral and dental problems in the organ transplant patient

The number of people receiving organ transplants has dramatically increased over the last decade. It is now likely that a dental surgeon will come across patients who have undergone transplantation. This paper considers the particular problems that these patients are likely to present their general dental practitioners.

Amlodipine-induced gingival overgrowth

Amlodipine is a calcium channel blocker used in the management of angina and hypertension. We report 3 cases of gingival overgrowth in adult dentate patients associated with chronic usage of this drug. Gingival changes occurred within 3 months of dosage and appeared to be compounded by the patient's existing periodontal condition. In all 3 patients, there was sequestration of amlodipine in their crevicular fluid. The significance of this finding in relation to the pathogenesis of this unwanted effect remains to be elucidated.

The effect of systemically-administered flurbiprofen as an adjunct to toothbrushing on the resolution of experimental gingivitis

Non-steroidal anti-inflammatory drugs (NSAIDs) have been widely researched in an attempt to control periodontal diseases. This double-blind parallel group study investigated the effect of a systemic flurbiprofen preparation (100 mg daily), when combined with toothbrushing on the resolution of experimental gingivitis in human volunteers. 47 volunteers abstained from tooth cleaning for 21 days. On day 21, 23 subjects were prescribed 100 mg of flurbiprofen daily whereas 24 subjects were prescribed placebo. In both groups, toothbrushing was re-introduced and all subjects used the Bass technique for 2 min each day. Both treatment regimens were continued for 7 days. Plaque indices, gingival indices and gingival crevicular fluid flow were assessed at baseline (day 0) and on days 21 and 27. There were no significant differences at p = 0.05 between the groups for plaque indices or gingival crevicular fluid flow. The flurbiprofen group, however, demonstrated greater resolution of gingival inflammation by day 27 when compared to the placebo controls (p = 0.04). The plasma levels of flurbiprofen in the test group showed mean concentrations of flurbiprofen of 4.7 (+/- 2.1) micrograms/ml at 1 h after dosing. After 6 h, this had fallen to 4.4 (+/- 1.6) micrograms/ml. It is concluded that these serum concentrations of flurbiprofen are sufficient to produce significant anti-inflammatory effects in the gingival tissues.

The efficacy of locally applied morphine in post-operative pain after bilateral third molar surgery

1. Recent evidence has hinted at a peripheral site of action of morphine analgesic efficacy. 2. Previous studies by the same authors have developed a model for testing local analgesic efficacy by placing drugs into tooth sockets after third molar surgery. 3. The present studies test the hypothesis of local morphine activity at two dosage concentrations, 100 ng ml-1 and 100 micrograms ml-1 after third molar surgery. 4. No significant analgesic efficacy was found at either dose when compared with placebo.

The use of third molar surgery in clinical pharmacology

This review discusses the various sequelae that arise after third molar surgery and their use for assessing the efficacy of a variety of therapeutic measures. The surgical procedure provides an opportunity to investigate onset, depth, duration and possible systemic effects of local anaesthetic solutions. Also, the anxiety which often accompanies such surgery lends itself to the appraisal of different anxiolytic agents and sedation techniques. The immediate postoperative sequelae of pain, buccal swelling and trismus provides a useful clinical model for evaluating the efficacy of analgesics and anti-inflammatory drugs. Third molar tooth sockets are susceptible to infection and this propensity enables the assessment of different antibiotic regimens. A further advantage of the third molar model is its application for crossover studies, with the patient acting as their own control. Very few surgical procedures afford this facility, which further adds to the value of this model in clinical pharmacology.

Drug-induced gingival overgrowth and its management

Gingival overgrowth is associated with the chronic usage of phenytoin, cyclosporin and the dihydropyridines. The pathogenesis of this unwanted effect is uncertain but appears to be enhanced by plaque-induced gingival inflammation. Certain patients appear to be more susceptible to gingival overgrowth and this may be related to gingival fibroblast phenotypes. In most cases, treatment involves surgical excision, followed by a concentrated oral hygiene programme. Recurrence of gingival overgrowth is a persistent problem particularly in the 'responder' patients. If an alternative, suitable medication is available, it may be worth while considering such a change through consultation with the patient's physician. Since patients are retaining their teeth into old age, the prevalence of this unwanted effect is likely to increase.

Determination of nifedipine in gingival crevicular fluid: a capillary gas chromatographic method for nifedipine in microlitre volumes of biological fluid

This paper describes a sensitive capillary gas chromatographic (GC) method for the determination of nifedipine in sub-microliter samples of gingival crevicular fluid (GCF) in order to assess if nifedipine is present in the GCF and if so, whether the local tissue concentrations of this drug are an important determinant in the development of gingival overgrowth. Liquid-liquid and solid-phase extraction were combined to give adequate sample clean-up and concentration for measurement by automated capillary GC with electron capture detection. Nifedipine and its principal metabolite, M-I, were analysed in both plasma and GCF in 9 adult male patients who had been taking nifedipine for over six months. M-I could not be measured in GCF. Plasma nifedipine and M-I levels were normal, but the nifedipine levels found in the GCF of 7 patients (including all those with overgrowth) were remarkably elevated, 15 to 316-fold greater. This massive concentration of nifedipine into the GCF is therefore linked with gingival overgrowth. This is the first time that a GC method has been developed which permits determination of GCF pharmacokinetics of a drug which causes gingival overgrowth, and further investigation will lead to a better understanding of the tissue mechanisms involved.