Pathogenesis of postoperative oral surgical pain

Pain is a major postoperative symptom in many oral surgical procedures. It is a complex and variable phenomenon that can be influenced by many factors. Good management of oral surgical pain requires a detailed understanding of the pathogenesis of surgical pain. This article aims at reviewing postoperative pain from a broad perspective by looking into the nociception, neuroanatomy, neurophysiology, and neuropharmacology of pain. Therapeutic recommendations are made after reviewing the evidence from the literature for maximizing the efficacy of pain management techniques for oral surgical pain.

Maximizing the safety of nonsteroidal anti-inflammatory drug use for postoperative dental pain: an evidence-based approach

This article reviews the use of nonsteroidal anti-inflammatory drugs (NSAIDs) for postoperative dental pain. An evidence-based approach is used to evaluate the clinical studies to date on the safe use of these drugs in dental patients. No drugs are without adverse effects or are perfectly safe, but their safe use in clinical practice would entail maximizing the therapeutic efficacy and minimizing the adverse effects. Therapeutic recommendations are made after reviewing the evidence for the safe use of NSAIDs in postoperative dental pain.

Oral myofibromatosis: an unusual cause of gingival overgrowth

BACKGROUND

This case report describes a rare benign tumour, which presented as discrete areas of gingival hyperplasia affecting both the mandible and the maxilla.

METHOD

Surgical excision of the lesions was carried out under local anaesthetic. Histopathological examination confirmed the diagnosis of oral myofibromatosis.

RESULTS

The condition responded to surgical excision and appears to have limited growth potential. It affects a wide spectrum of ages and can be alarming due to rapid enlargement and ulceration, so careful diagnosis is important to avoid unnecessary aggressive treatment.

Are dental infections a cause of brain abscess? Case report and review of the literature

Dental pathology and/or treatment have been linked to a small number of brain abscesses as possible sources of infection. A further case is presented, in which a dental site is implicated. A review of the evidence was undertaken. A wide range of dental procedures had been implicated. In some cases the brain isolate was not of dental origin. In many, the diagnosis was one of exclusion. In order to confirm the role of odontogenic infection in the pathogenesis of brain abscess, modern sampling techniques should be used to precisely identify the isolates. The causal organism should be identified in both oral and cranial sites.

Photographic scoring of gingival overgrowth

BACKGROUND

A wide range of methods have been employed to determine the severity of gingival overgrowth resulting in uncertainty regarding the prevalence of the side-effect. There is no simple, non-invasive, objective, blind method for assessing gingival overgrowth.

AIM

This article aims to describe a method which is suitable for use in large-scale population studies.

MATERIALS AND METHODS

Photographs were taken of the anterior, buccal gingivae and teeth of 925 patients medicated with calcium channel blockers. In addition, each patient was ascribed a clinical gingival overgrowth score. 100 patients had repeat photographs, and a further 10 patients had alginate impressions taken. The models were scored for severity of gingival overgrowth using a described technique. The slides were scored using a modification of this technique.

RESULTS

When photographic and study model scores were compared, photographic scores were consistently higher, and as a result, a photographic score of 38.6% was considered to represent a significant overgrowth. There was good agreement between clinically determined scores and photographic scores (kappa=0.71).

CONCLUSIONS

The results indicate that this method is suitable for large-scale population studies where it also has the advantage of providing a continuous scale of gingival changes for subsequent statistical analysis.

Infective endocarditis, dentistry and antibiotic prophylaxis; time for a rethink?

OBJECTIVE

To provide a critical review of the current evidence that links dental treatment to infective endocarditis (IE) and appraise the risks of antibiotic chemoprophylaxis.

DESIGN

Retrospective analysis

SETTING

Mainly hospital based patients or subjects

OUTCOME MEASURES

The interrelationship between infective endocarditis and dental treatment is complex and in many instances uncertain. The risk from antibiotic chemoprophylaxis appear greater than the risk of contracting IE.

RESULTS

There is increasing evidence that spontaneous bacteraemia are more likely to cause IE in at risk patients than specific episodes of dental treatment. Antibiotic chemoprophylaxis may not necessarily reduce dental-induced bacteraemia and the protective effect if any from antibiotic cover may arise from an inhibitory action upon bacterial colonisation on the compromised cardiac valves.

CONCLUSION

There is increasing concern over the misuse of antibiotics in general and this has focused attention on chemoprophylaxis in dentistry to prevent IE. New evidence on dental-induced bacteraemia and the prevalence of IE in association with dental treatment raises further questions on the need to provide antibiotic cover in at risk patients. More prescriptive guidelines to define who is at risk from IE and what procedures require cover will help to reduce overprescribing of antibiotics and reduce the risks of their unwanted effects.

An investigation into the efficacy of intravenous diclofenac in post-operative dental pain

OBJECTIVE

To evaluate the efficacy of single doses of intravenous diclofenac sodium (25, 50 and 75 mg) in patients with post-operative pain after third-molar surgery in a randomised, placebo-controlled study.

METHODS

Two hundred and sixty-nine patients (168 females) who required the removal of their impacted third molars participated in the study, which had received prior ethical approval. Surgery was completed under general anaesthesia and, during the early post-operative period, patients received either a single intravenous dose of diclofenac (25, 50 or 75 mg) or matched placebo in random, double-blind order. Pain intensity was assessed on 10-cm visual analogue scales at fixed time points throughout a 4-h investigation period. Other efficacy variables obtained included time until rescue medication and overall assessment at 4, 6, 12 and 24 h after dosing.

RESULTS

Throughout the 4-h investigation period, patients treated with diclofenac reported significantly less pain than those treated with placebo (P < 0.001). No differences were observed among the three doses of diclofenac (P = 0.22). Similar results were observed at 6, 12 and 24 h after dosing. Significant differences were also noted between the placebo group and all the diclofenac treatment groups with respect to time until rescue medication (P < 0.001) and the proportion of patients taking such medication.

CONCLUSION

Single doses of i.v. diclofenac (25, 50 and 75 mg) provide significant pain relief after third-molar surgery. The efficacy of this preparation does not appear to be dose related.

Risk factors for drug-induced gingival overgrowth

BACKGROUND/AIMS

Drug-induced gingival overgrowth remains a significant problem for the periodontologist. Many patients medicated with the drugs implicated in this unwanted effect experience significant, recurrent gingival problems that require repeated surgical excisions. In this review, we attempt to identify and quantify the various "risk factors" associated with both the development and expression of the drug-induced gingival changes.

METHOD

The risk factors appraised include age, sex, drug variables, concomitant medication, periodontal variables and genetic factors. Elucidation of such factors may help to identify "at risk patients" and then develop appropriate treatment strategies.

RESULTS

Of the factors identified, the only one that can be affected by the periodontologist is the patents' periodontal condition. However, drug variables and concomitant medication do impact upon the expression of gingival overgrowth.

CONCLUSION

The identification of risk factors associated with both the prevalence and severity of drug-induced gingival overgrowth is important for all parties involved with this unwanted effect. Both periodontologist and patient have an important rôle to play in improving oral hygiene and gingival health. Likewise, there is always an opportunity to establish a close liaison between the patient's physician and the periodontologist to try and identify alternative drug regimens that can help reduce the impact of this unwanted effect.

The efficacy of buffered ketoprofen in postoperative pain after third molar surgery

OBJECTIVE

To evaluate in a randomised, double-blind, placebo-controlled trial, the efficacy (time to onset of meaningful pain relief) of single doses of buffered ketoprofen (12.5 mg) and ibuprofen (200 mg) in 180 patients with postoperative pain after third molar surgery.

METHODS

180 adult patients who had undergone third molar surgery under general anaesthesia participated in this study. After dosing, patients recorded their time to meaningful pain relief, pain intensity on both visual analogue scales and verbal rating scales, pain relief and the need for additional analgesia. Pain recordings were made at fixed time points over a 6-h investigation period.

RESULT

Buffered ketoprofen (12.5 mg) provided quicker meaningful pain relief than placebo (P = 0.023). For secondary efficacy measures (SPIDS4, SPIDS6, TOTPAR4, TOTPAR6), the buffered ketoprofen was significantly superior to both placebo (P < 0.001) and ibuprofen (200 mg) (P < 0.05). Similarly, the amount of time before taking an escape analgesic was significantly less in the placebo group than both the ibuprofen and buffered ketoprofen groups (P < 0.03).

CONCLUSIONS

Buffered ketoprofen (12.5 mg) provides effective pain control in the early postoperative period after third molar surgery. This ketoprofen preparation was also superior to ibuprofen (200 mg) with respect to both reducing pain intensity and providing an earlier onset of pain relief.

The effect of multiple anticonvulsant therapy on the expression of phenytoin-induced gingival overgrowth

The potential effect of co-medication with phenobarbitone, primidone and carbamazepine on plasma and saliva concentrations of 5-(4-hydroxyphenyl)-5-phenylhydantoin (4-HPPH), the major metabolite of phenytoin in man and on the incidence of phenytoin-induced gingival overgrowth was investigated in a group of 36 adult epileptic patients. There were no significant differences in plasma or saliva concentrations of 4-HPPH or phenytoin in patients prescribed phenytoin alone, compared to those who received phenytoin with either phenobarbitone, primidone, or carbamazepine. In addition, the extent and the incidence of gingival overgrowth were similar in the 2 groups. The results suggest that chronic co-medication with other anti-convulsant drugs which induce phenytoin metabolism, does not affect the plasma or saliva 4-HPPB steady-state levels, nor the degree of gingival overgrowth in adult epileptic patients on therapy with phenytoin.

An investigation into the need for supplementary steroids in organ transplant patients undergoing gingival surgery. A double-blind, split-mouth, cross-over study

Organ transplant patients are frequently medicated with triple immunosuppressive therapy that includes both cyclosporin and the corticosteroid, prednisolone. Many of these patients experience gingival overgrowth that necessitates surgical intervention. Chronic dosing with corticosteroids can lead to suppression of the hypothalamic-pituitary axis, and subsequent adrenocortical suppression. To circumvent possible suppression, supplementary steroids are administered to such patients prior to so-called "stressful events". We have examined the need for supplementary steroids in 20 organ transplant patients undergoing gingival surgery under local anaesthesia to correct their drug-induced gingival overgrowth. All patients were operated upon in the first half of the morning. Prior to gingival surgery, resting blood pressure (BP) and serum ACTH concentrations were determined. Immediately before surgery patients received either intravenous hydrocortisone 100 mg or placebo in random, double-blind order. Each patient required 2 gingivectomies and thus acted as their own placebo control. BP was measured at various time points throughout surgery and upto 2 h postoperatively. On completion of surgery, a further blood sample was taken to determine ACTH concentration. There was no significant difference (p>0.05) between placebo and hydrocortisone treatments for BP and ACTH measurements. No patient experienced any symptoms that were suggestive of adrenocortical suppression. One patient did experience postural hypotension prior to gingival surgery, but this is attributed to his antidepressant medication. We can conclude from this study that immunosuppressed organ transplant patients taking the maintenance dose of prednisolone (5-10 mg/day) do not require corticosteroid cover prior to gingival surgery under local anaesthesia. We would however, advocate monitoring of their blood pressure throughout the procedure.

The efficacy of a novel adenosine agonist (WAG 994) in postoperative dental pain

AIMS

To determine the comparative efficacy of a new novel adenosine agonist (WAG 994) in postoperative pain after third molar surgery.

METHODS

One hundred and twenty-two patients with postoperative pain after third molar surgery were randomised in a placebo double-blind trial with an active control group. In the early postoperative period patients received either a single dose of WAG 994 1 mg, ibuprofen 400 mg or matched placebos. Pain intensity score was recorded on serial visual analogue scales over a 6 h investigation period. Similarly, pain relief was completed on a 4 point categorical scale at each evaluation point. Patients had access to escape analgesic and if these were taken, the time and dosage were recorded. A sparse sampling technique was used to investigate the relationship between analgesic effects and plasma concentrations of WAG 994.

RESULTS

All three treatment groups were matched for various demographic variables. For all efficacy measures, WAG 994 was not significantly different from placebo (P >0.05), whereas ibuprofen 400 mg was significantly superior to placebo (P<0.001). No significant relationships (P<0.05) were found between WAG 994 pharmacokinetic variables and efficacy measures. Conclusion WAG 994, an adenosine agonist, did not show efficacy in the management of postoperative pain after third molar surgery. Although this pain responds well to nonsteroidal anti-inflammatory drugs, it appears to be resistant to compounds that interact with purinergic receptors.

Phenytoin metabolism to 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) in man, cat and rat in vitro and in vivo, and susceptibility to phenytoin-induced gingival overgrowth

Interspecies differences in phenytoin (PHT) metabolism to 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) were examined in human, cat and rat hepatic microsomes in vitro. Rat liver microsomes were 25 and 650 times more efficient at the conversion of PHT to HPPH than human and cat liver microsomes, respectively. Sulphaphenazole (83%) and tolbutamide (TOL) (64%) were the most potent inhibitors of HPPH formation in human liver microsomes, while ciprofloxacin (27%), enoxacin (27%) and TOL (26%) produced the greatest inhibition in cat liver microsomes. TOL was tested for its effect on HPPH formation and gingival overgrowth in cats in vivo. Eight cats received PHT sodium (4 mg/kg/d) and another 8 cats received PHT sodium together with TOL (20 mg/kg/d) for 10 wk. Six cats (75%) in the PHT group and 4 cats (50%) in the PHT & TOL group developed significant gingival overgrowth by the end of the study. However, the extent and incidence of the overgrowth were similar in the 2 groups. There were no significant differences in mean AUC 0-10 weeks for plasma PHT (552.90 +/- 29.6 micrograms.d/mL [PHT alone] vs. 582.41 +/- 24.49 micrograms.d/mL [PHT & TOL]) and unconjugated HPPH (1016.4 +/- 295.5 ng.d/mL [PHT alone] vs. 1174.5 +/- 397.2 ng.d/mL [PHT & TOL]) concentrations between the 2 groups of cats. Neither PHT nor HPPH were detectable in the plasma of 8 rats which received PHT (4 mg/kg/d) over a 10-wk period. The rats showed no sign of gingival inflammation (mean gingival index = 0) or gingival overgrowth (mean gingival overgrowth index = 0). Thirty-six adult epileptic patients on chronic PHT therapy were examined; 17 (47%) of the patients demonstrated clinically significant overgrowth. The mean steady-state plasma PHT concentration was comparable to, and the mean plasma unconjugated HPPH concentration 5-fold greater than, that observed in the cats. The results suggest that the rapid metabolism and elimination of PHT and HPPH in the rat may enable it to become more resistant towards developing gingival overgrowth, compared to the cat and man.

Prevalence of gingival overgrowth induced by calcium channel blockers: a community-based study

BACKGROUND

The prevalence of gingival overgrowth induced by chronic medication with calcium channel blockers is uncertain. Although there have been several studies examining this question, the results are conflicting, with previous estimates ranging from 20% to 83%. There have been only 2 studies examining the prevalence of overgrowth induced by diltiazem and amlodipine, with estimates of 74% and 3.3%, respectively.

METHODS

The current study aimed to address the problems associated with these studies by examining a sample of patients taking one of 3 calcium channel blockers, who were drawn from a community-based population in northeastern England. Nine hundred eleven (911) subjects were recruited from general medical practices in the area. Of these, 442 were taking nifedipine, 181 amlodipine, and 186 diltiazem. In addition, 102 control subjects were examined. Drug and demographic data for each subject were recorded. The periodontal condition of all subjects was assessed including plaque index, papillary bleeding index, and a photograph of the anterior gingivae for subsequent analysis of overgrowth severity.

RESULTS

More than six percent (6.3%) of subjects taking nifedipine were seen to have significant overgrowth. This overgrowth was statistically greater than the amount of overgrowth seen in either of the other 2 drug groups or the control population. The prevalence of gingival overgrowth induced by amlodipine or diltiazem was not statistically significant when compared to the control group. The severity of overgrowth within the nifedipine group was found to be related to the amount of gingival inflammation and also to the gender of the subject, with males being 3 times as likely to develop overgrowth than females.

CONCLUSIONS

The prevalence of clinically significant overgrowth related to chronic medication with calcium channel blockers is low, i.e., 6.3% for nifedipine. Males are 3 times as likely as females to develop clinically significant overgrowth. The presence of gingival inflammation is an important cofactor for the expression of this effect.

The comparative efficacy of aceclofenac and ibuprofen in postoperative pain after third molar surgery

The aim of the present placebo-controlled, double-blind study was to evaluate the comparative efficacy of single doses of aceclofenac 150 mg and ibuprofen 400 mg in 217 patients with postoperative pain after third molar surgery. Outcome of primary efficacy was judged by overall assessment of the area under the curve (AUC) of graphs for pain intensity (AUC pain) pain relief (AUC relief), both measured from serial visual analogue scales over a 6 h investigation period. Other measures of efficacy included the rate of pain reduction in the first hour, the number of patients who took 'escape' analgesics and the time before they did, and an overall assessment of pain relief score on a five-point categorical scale. Ibuprofen 400 mg was significantly superior to placebo for pain relief (P < 0.01), degree of pain reduction in the first hour (P = 0.005), and the number of patients who required escape analgesia (P < 0.001), and the time before they did (P < 0.001). The outcome for patients treated with aceclofenac 150 mg was not significantly different from that of patients treated with placebo (P > 0.05). A single dose of ibuprofen 400 mg provided significant pain relief in the early postoperative period after third molar surgery, whereas a single dose of aceclofenac 150 mg was not effective in the management of postoperative pain after this operation.

Immunolocalization of collagenase (MMP-1) and stromelysin (MMP-3) in the gingival tissues of organ transplant patients medicated with cyclosporin

Cyclosporin-induced gingival overgrowth results from a disturbance in the homeostatic balance in the gingival tissues which is characterised by both an increase in the number of fibroblasts and in the volume of the extracellular matrix. Whilst the accumulation of the collagenous matrix is well recognised, little attention has been paid to the role of the degradative enzymes in the development of this condition in vivo. The matrix metalloproteinases MMP-1 (collagenase) and MMP-3 (stromelysin) were immunolocalized using specific polyclonal and monoclonal antisera in gingival specimens from 18 patients with drug-induced gingival overgrowth and 6 control subjects. A positive granular pattern of MMP-1 staining was seen in the vast majority of fibroblasts in specimens from drug-free controls throughout the connective tissue. This was in marked contrast to the findings in overgrown tissue, where positive cytoplasmic staining was shown by only a small number of fibroblasts. Where fibroblast staining occurred in overgrown tissue, the intracellular pattern was the same as in the drug free tissue. Positive staining was, however, largely confined to a small number of fibroblasts in the lamina propria of the outer gingival mucosa and even in this region there were areas that showed little or no fibroblast staining. This apparent cessation of collagenase production by many of the fibroblasts in gingival overgrowth supports the hypothesis that perturbation of collagenase activity is responsible for the disturbance in the homeostatic balance, which is pivotal to this condition.

Is there a link between periodontal disease and coronary heart disease?

OBJECTIVE

To provide a critical review of the studies completed to date that have investigated a link between coronary heart disease and dental health.

DESIGN

Retrospective analysis.

SETTING

Mainly hospital-based patients or subjects involved in longitudinal health care studies.

MAIN OUTCOME MEASURES

The incidence of coronary heart disease and its relationship to dental health and other recognised risk factors.

RESULTS

Evidence suggests that dental health, in particular periodontal disease, may be a significant risk factor for coronary heart disease and further coronary events. Possible biological mechanisms that link the two diseases are appraised.

CONCLUSIONS

There does appear to be increasing evidence that a relationship exists between dental health and coronary heart disease, especially in males aged 40-50 years. The presence of a hyperinflammatory monocyte phenotype may provide a common biological mechanism that links the two diseases.

Angiotensin converting enzyme (ACE) inhibitors and their implications for the dental surgeon

Angiotensin enzyme converting (ACE) inhibitors are a widely prescribed group of drugs used in the management of hypertension and heart failure. Several unwanted effects are associated with ACE inhibitors and this paper highlights those significant to the dental surgeon. Of particular concern is the problem of angioedema, which can be life threatening. Three case reports are presented that illustrate this problem and the management is discussed.

Oral lesions in organ transplant patients

Patients who have undergone organ transplantation can present with a variety of oral lesions that appear to be related either directly to their medication or arise as a consequence of drug-induced immunosuppression. Such lesions include hairy leukoplakia, an increased propensity to both fungal and viral infections and a high incidence of malignant change, especially lip cancer. Cyclosporin remains the immunosuppressant of choice in most transplant patients. Gingival overgrowth is the main unwanted oral effect associated with cyclosporin. Some 30% of dentate transplant experience this problem, which is further compounded by concomitant medication with a calcium channel blocker. This review appraises the various oral problems that can arise in this group of patients and emphasises the importance of regular oral screening and the establishment of links with the various transplant teams.

Are the pharmacokinetics of ibuprofen important determinants for the drug's efficacy in postoperative pain after third molar surgery?

The aim of the present placebo-controlled, crossover study was to evaluate the efficacy and pharmacokinetics of ibuprofen after a single oral dose of soluble ibuprofen 400 mg in 18 patients with postoperative pain after bilateral third molar surgery. Throughout a 5-hour investigation period, patients reported significantly less pain (P < 0.001) after treatment with soluble ibuprofen than after placebo. Peak plasma concentrations of ibuprofen occurred approximately 30 minutes after dosage. No significant correlations (P > 0.05) were observed between efficacy measures and the various pharmacokinetic parameters (AUC0-300, Cmax and Tmax) for ibuprofen after the soluble dose. It is concluded that a single dose of soluble ibuprofen 400 mg is an effective analgesic for the control of postoperative pain in the early period after third molar surgery. Efficacy of this preparation does not appear to be directly related to the drug's pharmacokinetic variables in plasma.

Nifedipine pharmacological variables as risk factors for gingival overgrowth in organ-transplant patients

The prevalence and severity of gingival overgrowth in organ-transplant patients medicated with cyclosporin are greater in patients concomitantly medicated with nifedipine; however, no relationship between the gingival overgrowth and any of the nifedipine pharmacological variables has been demonstrated. The study examined the effect of five nifedipine pharmacological variables (nifedipine dosage, plasma concentration and gingival crevicular fluid concentration, M1 metabolite plasma concentration and the nifedipine: M1 ratio). The effect of the nifedipine variables on the gingival overgrowth score were examined using univariate and multivariate regression analysis. Adjustment for the effect of other risk factors was made by adding the distribution of each of the nifedipine variables in turn to a stepwise regression model containing previously identified risk factors for this condition. Despite the high levels of nifedipine sequestered in the GCF, only the plasma concentration of nifedipine was identified as a risk factor for the severity of gingival overgrowth in these patients (P = 0.01) once adjusted for other known risk factors (R2 for the model = 55%).