The effect of chlorhexidine mouthrinses on the human oral flora

The importance and provision of oral hygiene in surgical patients

The provision of mouth care on the general surgical ward and intensive care setting has recently gained momentum as an important aspect of patient care. Oropharyngeal morbidity can cause pain and disordered swallowing leading to reluctance in commencing or maintaining an adequate dietary intake. On the intensive care unit, aside from patient discomfort and general well-being, oral hygiene is integral to the prevention of ventilator-associated pneumonia. Chlorhexidine (0.2%) is widely used to decrease oral bacterial loading, dental bacterial plaque and gingivitis. Pineapple juice has gained favour as a salivary stimulant in those with a dry mouth or coated tongue. Tooth brushing is the ideal method of promoting oral hygiene. Brushing is feasible in the vast majority, although access is problematic in ventilated patients. Surgical patients undergoing palliative treatment are particularly prone to oral morbidity that may require specific but simple remedies. Neglect of basic aspects of patient care, typified by poor oral hygiene, can be detrimental to surgical outcome.

Adsorption of chlorhexidine and black tea onto in vitro salivary pellicles, as studied by ellipsometry

The adsorption from 0.2% (w/w) chlorhexidine and black tea solutions onto an in vitro pellicle from whole unstimulated saliva on hydroxyapatite discs was studied by ellipsometry. It was found that chlorhexidine adsorbed to the pellicle and caused a modification of the pellicle properties, leading to a subsequent increase in adsorption of salivary and black tea components. There was a distinct order-of-addition effect, whereby chlorhexidine followed by black tea gave an overall greater adsorption of components compared with black tea followed by chlorhexidine. This increase in adsorption resulted in a concomitant increase in color or stain, as measured by a reflectance chromameter. The increase in adsorbed amounts and stain was modified, in part, by the adsorption of salivary fractions between the chlorhexidine and black tea treatments. In all cases, the chlorhexidine and black tea-modified pellicles were not readily removed by either phosphate or sodium dodecyl sulfate rinses. Thus, following exposure to chlorhexidine, the accelerated adsorption of salivary and black tea components can ultimately lead to increased staining of the pellicle.

A preliminary study of the effect of probiotic Streptococcus salivarius K12 on oral malodour parameters

AIMS

To determine whether dosing with bacteriocin-producing Streptococcus salivarius following an antimicrobial mouthwash effects a change in oral malodour parameters and in the composition of the oral microbiota of subjects with halitosis.

MATERIALS AND RESULTS

Twenty-three subjects with halitosis undertook a 3-day regimen of chlorhexidine (CHX) mouth rinsing, followed at intervals by the use of lozenges containing either S. salivarius K12 or placebo. Assessment of the subjects' volatile sulphur compound (VSC) levels 1 week after treatment initiation showed that 85% of the K12-treated group and 30% of the placebo group had substantial (>100 ppb) reductions. The bacterial composition of the saliva was monitored by culture and PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Changes in the PCR-DGGE profiles occurred in most subjects following K12 treatment. In vitro testing showed that S. salivarius K12 suppressed the growth of black-pigmented bacteria in saliva samples and also in various reference strains of bacteria implicated in halitosis.

CONCLUSIONS

Administration of bacteriocin-producing S. salivarius after an oral antimicrobial mouthwash reduces oral VSC levels.

SIGNIFICANCE AND IMPACT OF THE STUDY

The outcome of this preliminary study indicates that the replacement of bacteria implicated in halitosis by colonization with competitive bacteria such as S. salivarius K12 may provide an effective strategy to reduce the severity of halitosis.

Effect of water-soluble reduced chitosan on Streptococcus mutans, plaque regrowth and biofilm vitality

The purpose of the present study was to examine the effects of a newly developed water-soluble reduced chitosan on Streptococcus mutans, plaque regrowth, and biofilm vitality. A 1.0%, water-soluble reduced chitosan, with pH ranging from 6.0 to 6.5, molecular weights between 3,000 and 5,000 Da, and 70% degree of deacetylation, was used. To determine antibacterial and antiplaque potency of chitosan, minimal inhibitory concentrations (MICs) for S. mutans and S. sanguinis (formerly S. sanguis), short-term exposure to S. mutans, and clinical trial of plaque regrowth and biofilm vitality were conducted. Twelve dental students volunteered to participate in the 6-week, double blind, randomized clinical trial using the classical 4-day plaque regrowth design. The MIC of water-soluble reduced chitosan for S. mutans was 1.25 g/l. While the cells exposed to distilled water (DW) grew rapidly, with a maximum turbidity reached by 16 h postinoculation, S. mutans exposed to chitosan (5.0 g/l) exhibited a substantial delay in growth and reached a maximum turbidity by 32 h postinoculation. The chitosan solution reduced the plaque index and the vitality of the plaque flora significantly when compared to DW, but this was less than the reductions found with the positive control of 0.1% chlorhexidine solution. The water-soluble reduced chitosan exhibited potent antibacterial effect on S. mutans, and displayed a significant antibacterial and plaque-reducing action during the 4-day plaque regrowth.

Microbial Analysis of the Autogenous Bone Collected by Bone Filter During Oral Surgery: A Clinical Study

PURPOSE

The purposes of the study presented are to identify the microbial content of the collected bone debris and to determine the antibacterial efficiency of chlorhexidine mouth rinse in reducing the microbial content of the collected bone debris.

PATIENTS AND METHODS

Twenty-five patients who had asymptomatic fully impacted mandibular third molars bilaterally underwent surgical removal for prophylactic and orthodontic considerations. Immediately before surgery all patients rinsed with 10 mL of their assigned solution (chlorhexidine or sterile saline) for 2 minutes. Before surgical removal of the teeth, bone debris was collected with a stringent aspiration protocol from the ramus by bone filter. The microbial content of the bone debris was assessed and the bacterial levels between the 2 groups were compared statistically.

RESULTS

All samples from both groups (chlorhexidine or sterile saline) yielded viable microorganisms. There was no significant difference between the mean/median colony-forming units (CFU)/g values of both group samples, for aerobes (Streptococcus salivarius) and anaerobes (Bacteroides, Peptococcus, Peptostreptococcus, and Veillonella species). With regard to total microorganisms, the mean CFU/g derived from the chlorhexidine group samples were 1.5 x 10(8) CFU/g per bone sample compared with 1.5 x 10(9) CFU/g for the sterile saline control group (P < .05).

CONCLUSION

Although chlorhexidine rinsing immediately before surgery reduced the levels of total microorganisms when compared with stringent aspiration protocol alone, it has not been found effective on aerobic Streptococcus salivarius and, importantly, on anaerobes. The reduced bacterial levels may still carry high infectious risk and may lead to failure in autogenous grafting procedures in oral surgery.

The effect of a polyhexamethylene biguanide mouthrinse compared with a triclosan rinse and a chlorhexidine rinse on bacterial counts and 4-day plaque re-growth

OBJECTIVES

For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% and a 0.12% PHMB mouthwash were shown to inhibit plaque re-growth and to reduce oral bacterial counts. In this study, a 0.2% PHMB mouthrinse (A) was compared with a positive control 0.12% aqueous chlorhexidine solution (B), a commercially available 0.3% triclosan/2.0% polyvinyl methyl ether maleic acid copolymer mouthrinse (Colgate Total Plax) (C), and a negative control placebo rinse (10% ethanol, flavour) (D).

MATERIALS AND METHODS

The controlled clinical study was a double blind, randomized, four replicate cross - over design. Plaque re-growth was assessed with the Turesky et al. (1970) modification of the Quigley & Hein (1962) plaque index. The antibacterial effect was assessed by taking bacterial counts on the tooth surface (smears from the buccal surface of 16/26) and mucosa (smears from the buccal mucosa in opposite of area 16/26) after the professional prophylaxis and after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. Sixteen volunteers participated and, on day 1 of each study period were rendered plaque-free, ceased toothcleaning, and rinsed twice daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. A 10-day wash-out period was carried out between each rinse evaluation. Data were analysed using ancova with Bonferroni HSD adjustment for multiple comparisons (colony forming units per sample) with a significance level alpha=0.05.

RESULTS

The 0.2% PHMB mouthrinse (A) was significantly better at inhibiting plaque than the placebo (D), but significant less effective than the 0.12% aqueous chlorhexidine solution (B). There is no significant difference between A and the 0.3% triclosan/2.0% copolymer mouthrinse (C). Bacterial count reductions (tooth surface and mucosa) with PHMB (A) were significantly greater compared with the placebo (D) and triclosan (C), but significantly lower compared with chlorhexidine (B) (tooth surface) and equally effective compared with chlorhexidine (B) (mucosa).

CONCLUSION

Consistent with previous studies, a PHMB mouthrinse was shown to inhibit plaque re-growth and to reduce oral bacterial counts, indicating that PHMB could be an alternative to established mouthrinses in preventive applications.

Plaque inhibition of two commercially available chlorhexidine mouthrinses

BACKGROUND

Chlorhexidine (CHX) 0.2% solution is still "the leading oral antiseptic" for controlling gingivitis. Side effects, however, limit the acceptability to users and the long-term employment of a 0.2% CHX antiseptic in preventive dentistry. This stimulated the development of new formulations. The aim of the present study was to assess the effect on plaque inhibition and taste perception of two commercially available mouthrinses (0.12% CHX non-alcohol base with 0.05% cetyl pyridinium chloride (Cpc) versus 0.2% CHX alcohol base).

METHODS

The study was designed as a single-blind, randomized two group parallel experiment, to compare two different commercially available mouthrinses, during a 3-day plaque accumulation model. Forty healthy volunteers were enrolled in the study and received a thorough dental prophylaxis at the beginning of the test period. Over a 72-h experimental non-brushing period, during which subjects abstained from all forms of mechanical oral hygiene, one group (test) used a 15 ml alcohol free 0.12% CHX (=18 mg) mouthrinse on a Cpc base (Perioaid), CHX plus sign in circleCpc), twice daily for 30 s. The other group (control) used a 10 ml 0.2% CHX (=20 mg) mouthrinse on an 11.8% ethanol alcohol base (Corsodyl), CHX plus sign in circleAlc), twice daily for 60 s. After 72 h of plaque formation, the amount of plaque was evaluated. By the use of visual analogue scale, the subjects were asked for their appreciation of the taste of the mouthrinse they had used.

RESULTS

The mean plaque index for the CHX plus sign in circleCpc group was 0.97 and for the CHX plus sign in circleAlc group 0.78. After 72 h of non-brushing, there was no significant difference in plaque accumulation between the two groups. The answers to the questions (taste perception and after-taste) showed a statistically significant difference between the two groups. The mean visual analogue scale (VAS) scores for taste appreciation on a scale from very bad to very good taste (0-10) were 5.92 for the CHX plus sign in circleCpc group and 4.10 for the CHX plus sign in circleAlc group (p=0.02). The mean visual analogue scale (VAS) scores for the after-taste on a scale from very short to very long (0-10) were 7.24 for the CHX plus sign in circleCpc group and 5.38 for the CHX plus sign in circleAlc group.

CONCLUSIONS

Within the limitations of the present study design, it can be concluded that rinsing with a 0.12% CHX mouthrinse on a non-alcohol base with 0.05% Cpc (Perio-Aid) is not significantly different from rinsing with a 0.2% CHX mouthrinse on an alcohol base (Corsodyl). It appears that the subjects appreciated the taste of the non-alcohol CHX solution better but the after-taste of the rinse remained longer in the mouth.

Three different rinsing times and inhibition of plaque accumulation with chlorhexidine

AIM

This study assessed the plaque inhibiting effect of a 0.2% chlorhexidine (CHX) solution (Corsodyl) with three different rinsing times following a 72 h non-brushing period.

MATERIAL AND METHODS

The clinical investigation was a single-blind, randomised study involving 90 volunteer students (40 male and 50 female, mean age 23.2 years). Subjects were randomly allocated to one of three groups for which the protocol only differed with respect to the duration of rinsing. At the start of the trial, all participants received a dental prophylaxis to remove all plaque deposits. Subjects refrained from all mechanical oral hygiene procedures, but rinsed two times per day for the allocated duration with CHX mouth rinse over a period of 72 h. The chlorhexidine preparation was of 0.2% concentration used at a dose of 10 ml for either 15, 30 or 60 s. After 72 h, the Quigley & Hein plaque index (PI) from all volunteers was recorded at six sites per tooth. All participants received a questionnaire to evaluate their perception of rinsing duration.

RESULTS

After 72 h, the mean whole-mouth PI was 1.33, 1.18 and 1.24, respectively, for the 15, 30 and 60 s rinsing group. The difference in plaque scores between the three groups was not statistically significant. Results from the questionnaire showed a significant difference between the groups for their perception of rinsing duration.

CONCLUSIONS

No significant difference was observed in the level of plaque after 72 h of non-brushing whether the subjects rinsed for 15, 30 or 60 s with 0.2% chlorhexidine.

Comparative effects of different chlorhexidine mouth-rinse formulations on volatile sulphur compounds and salivary bacterial counts

AIM

To compare five different commercial mouth rinses with chlorhexidine (CHX) with respect to their anti-halitosis effect and anti-microbial activity on salivary bacterial counts, following a standardised research protocol. And secondly, to validate the study model proposed in the evaluation of patients suffering from halitosis.

PATIENTS AND METHODS

Ten volunteers, with a healthy oral status, were enrolled in a double-blind, cross-over design, using sterile saline as negative control and five CHX-containing mouth rinses: 0.12% CHX alone (CHX+NO), plus alcohol (CHX+ALC), plus 0.05% cetylpiridinium chloride (CHX+CPC), plus sodium fluoride (CHX+NaF), and 0.05% CHX plus 0.05% CPC, plus 0.14% zinc lactate (CHX+Zn). The levels of whole-mouth volatile sulphur compounds (VSCs) were measured by means of a sulphide monitor at baseline, 1 and 5 h after rinsing with the assigned product. Baseline measurements also included an organoleptic assessment and the recording of the tongue-coating index. Aerobic and anaerobic salivary bacterial counts were also obtained by collecting unstimulated saliva samples at the same evaluation times, and processed by culturing techniques. Analysis of variance was used to evaluate whether significant differences existed among groups, at each evaluation point, or in changes between evaluations.

RESULTS

No significant differences were detected at baseline, with VSC levels ranging between 190 and 227 parts per billion (p.p.b.) After rinsing, VSC levels were reduced with all products (except saline), after 1 h. Significant differences at 1 h were detected (p=0.04), corresponding to a lower amount of p.p.b. (109) in (CHX+Zn) as compared with the other groups (except CHX+NO). At 5 h, VSC levels were lower for CHX+CPC and CHX+Zn (155 and 169, respectively), while the other groups showed levels higher than 220 p.p.b. With respect to aerobic salivary bacterial counts, CHX+CPC demonstrated the lowest percentage of survival (6% after 1 h and 18% after 5 h). For anaerobic bacterial counts, again CHX+CPC demonstrated the lowest percentage of survival (10% at 1 h and 23% at 5 h), together with CHX+ALC (18% of survival at 5 h). However, salivary counts and VSCs were only significantly correlated at baseline, but not after treatment.

CONCLUSION

Important differences can be expected from different CHX formulations, in relation to both their anti-halitosis effect and anti-microbial activity in saliva. Formulations that combine CHX and CPC achieved the best results, and a formulation combining CHX with NaF resulted in the poorest.

Effects of post-surgical cleansing protocols on early plaque control in periodontal and/or periimplant wound healing

OBJECTIVE

The aim of this RCT was to evaluate early wound healing following specific post-surgical care protocols.

MATERIAL AND METHODS

Following periodontal flap surgery, 60 patients were randomly assigned to follow one of two post-surgical protocols. Subjects smoking >20 cigarettes per day were excluded. Patients following the control protocol rinsed twice daily for 1 min with 0.1% of chlorhexidine (CHX) for 4 weeks. In addition to CHX rinsing, patients assigned to the test protocol applied CHX locally using a special very soft surgical toothbrush (Chirugia) from days 3 to 14, and a soft toothbrush (Ultrasuave) from days 14 to 28, twice daily. Baseline measurements included gingival crevicular fluid (GCF) flow rate, probing depth, probing attachment level, presence of bleeding on probing and full-mouth plaque score. Measurements were repeated at 1, 2 and 4 weeks after surgery.

RESULTS

Both post-surgical protocols resulted in successful wound healing and optimal wound closure at 4 weeks. There were no statistical differences in the GCF flow rate between test and control protocols. There was a lower incidence of recession of > or =2 mm following the test protocol.

CONCLUSION

The use of specific post-surgical cleansing protocols including the introduction of mechanical cleansing at day 3, using local application of CHX in addition to daily rinsing with CHX may be recommended.

Analysis of the effects of chlorhexidine on oral biofilm vitality and structure based on viability profiling and an indicator of membrane integrity

Multispecies biofilms modeling interproximal plaque were grown on a hydroxyapatite substratum in a constant-depth film fermentor and then immersed in a viewing solution containing fluorescent indicators of membrane integrity. Confocal laser scanning microscopy (CLSM) revealed the structure and spatial distribution of cell vitality within the biofilms. Chlorhexidine gluconate (CHX) was added to the viewing solution to achieve concentrations of 0.05 and 0.2% (wt/vol) before further CLSM time-lapse series were captured. Image analysis showed that exposure to 0.2% CHX caused the biofilm to contract at a rate of 1.176 micro m min(-1) along the z axis and also effected changes in total fluorescence measurements and viability profiles through the biofilms after a delay of 3 to 5 min. At a concentration of 0.05% CHX, total fluorescence measurements for the biofilm exhibited barely detectable changes after 5 min. Fluorescence profiles (fluorescence versus time versus depth), however, clearly showed that a time-dependent effect was present, but the clearest indicator of the effect of dilute CHX over time was viability profiling. These findings suggest the possibility of using fluorescent indicators of membrane integrity in conjunction with viability profiling to evaluate the penetration of the bactericidal effects of membrane-active antimicrobial compounds into biofilm.

Effect of various chlorhexidine regimens on salivary bacteria and de novo plaque formation

AIM

The aim of the present experiment was to study the effect of different chlorhexidine regimens on the number of bacteria in saliva, and on de novo plaque formation.

MATERIAL AND METHODS

Ten subjects with gingivitis, but no signs of destructive periodontitis, were recruited. Following a screening examination, the volunteers were given oral hygiene instruction, meticulous scaling and professional mechanical tooth cleaning (PTC). The PTC was repeated once every 3 days during a 2-week period to establish healthy gingival conditions. The study was designed as a double-blind cross-over clinical trial including three phases. Each experimental phase comprised one preparatory period of 7 days and one plaque accumulation period (no oral hygiene measures) of 4 days. During all preparatory periods, the volunteers (i) performed mechanical tooth cleaning using a toothbrush and dentifrice and (ii) were, in addition, given two sessions of PTC. The final PTC was delivered after bacterial sampling had been made on Day 0. Preparatory period A: the participants continued the self-performed plaque control regimen that employed only mechanical means. Preparatory period B: the participants were in addition instructed to rinse and gargle, twice daily, with a 0.2% chlorhexidine mouthrinse. Preparatory period C: in addition to the above, the participants were instructed to brush the dorsum of the tongue for 60 s, twice daily, with a 1.0% chlorhexidine gel. Following each plaque accumulation period, there was a 10-day washout interval. The presence and amount of dental plaque (QHI) was scored after 1, 2 and 4 days of no oral hygiene. Samples of saliva were obtained on Day 0 and after 1 and 2 days. The samples were placed on Brucella agar plates and incubated (anaerobically) for 5 days. The total number of colony-forming units was determined and used to estimate the density of bacteria in saliva.

RESULTS

In period A, the mean QHI increased from 1.0 (Day 1) to 1.4 (Day 2) and 2.1 (Day 4). The corresponding scores for periods B and C were 0.5, 0.8, 1.6 and 0.3, 0.8, 1.2, respectively. At all re-examination intervals more plaque formed during period A than during periods B and C. Further, during period C, less plaque formed than that during period B. Saliva samples from Day 0 in period A contained a larger number of TVC than the baseline samples in periods B and C. There was no significant difference in TVC among the groups on Day 2.

CONCLUSION

The daily use of chlorhexidine as an adjunct to mechanical tooth cleaning markedly reduced the number of microorganisms that could be detected in saliva. The number of salivary bacteria may have influenced the amount of plaque that formed during an early phase of no oral hygiene.

Differences in antimicrobial activity of four commercial 0.12% chlorhexidine mouthrinse formulations: an in vitro contact test and salivary bacterial counts study

AIM

To evaluate the in vitro and in vivo antimicrobial activity of four commercial 0.12% chlorhexidine mouthrinses.

MATERIAL AND METHODS

The in vitro antimicrobial activity test consisted in a modified contact test where 20 selected bacterial species were tested during 1 min with each test product. After the contact, the inoculum was cultured, and the results were expressed in terms of survival/resistance and the percentage of survival as compared to a saline control. The in vivo test consisted of a double-blind, randomized, crossover salivary bacterial counts study. 10 volunteers rinsed during 1 min with each tested product. Saliva samples were obtained before rinsing, and after 5 min, and 1, 3, 5 and 7 h. These samples were cultured both aerobically and anaerobically. Percentages of survival, in regard to baseline, were calculated for each time point. Comparisons among products were tested using anova and selected paired t-test.

RESULTS

The in vitro contact test showed no survival in any tested species with CHX+CPC, while three species (Lactobacillus casei, Streptococcus mitis and Peptostreptococcus micros) were resistant to the other three products. CHX and CHX+NaF demonstrated additional resistant species (three and four species, respectively). The in vivo salivary bacterial counts test showed higher reductions of CHX+CPC and CHX+ALC in aerobic and anaerobic bacteria, lasting for 5 h. Significant differences were detected at multiple time points, when these two products were compared both with the control and the other tested products.

CONCLUSION

Important differences in activity, among 0.12% CHX products, were detected by both in vitro and in vivo tests. The formulation with alcohol was more active than those without alcohol, excepting the formulation with CHX+CPC, in which the reformulation and addition of CPC not only compensate but rather increase the antimicrobial activity.

Prophylaxis of radiation-associated mucositis in conventionally treated patients with head and neck cancer: a double-blind, phase III, randomized, controlled trial evaluating the clinical efficacy of an antimicrobial lozenge using a validated mucositis scoring system

PURPOSE

Mucositis occurs in almost all patients treated with radiotherapy for head and neck cancer. The aim of this multicenter, double-blind, prospective, randomized trial was to evaluate the clinical efficacy of an economically viable antimicrobial lozenge (bacitracin, clotrimazole, and gentamicin [BcoG]) in the alleviation of radiation-induced mucositis in patients with head and neck cancer.

PATIENTS AND METHODS

One hundred thirty-seven eligible patients were randomized to treatment with either antimicrobial lozenge (69 patients) or placebo lozenge (68 patients). The primary end point of the study was the time to development of severe mucositis from the start of radiotherapy. Secondary end points included severity and duration of mucositis, pain measurement, radiation therapy interruption, and quality of life. Mucositis was scored using a validated mucositis scoring system.

RESULTS

Toxicity profiles were similar between the two arms of the study. The median time to development of severe mucositis from the start of radiotherapy was 3.61 weeks on BCoG and 3.96 weeks on placebo (P =.61). There were no statistically significant differences between the arms in the extent of severe mucositis as measured by physician, in oral toxicities as recorded by patients, or in radiotherapy delays.

CONCLUSION

This study was conducted on the basis of a pilot study that demonstrated the BCoG lozenge to be tolerable and microbiologically efficacious. A validated mucositis scoring system was used. However, in this group of patients treated with conventional radiotherapy, the lozenge did not impact significantly on the severity of mucositis. Whether such a lozenge would be beneficial in treatment situations where rate of severe mucositis is higher (ie, in patients treated with unconventional fractionation or with concomitant chemotherapy) is unknown.

Effects of 0.2% chlorhexidine gluconate and amoxicillin plus clavulanic acid on the prevention of alveolar osteitis following mandibular third molar extractions

OBJECTIVE

The purpose of this study was to evaluate the use of a 0.2% chlorhexidine gluconate and amoxicillin plus clavulanic acid combination as a prophylactic therapy for the prevention of alveolar osteitis after mandibular third molar extractions and to investigate adverse reactions to chlorhexidine.

STUDY DESIGN

This randomized, placebo-controlled, parallel group study was conducted in a group of 177 subjects, from which 3 groups were formed. The first group (n = 62) received 0.2% chlorhexidine gluconate, the second group (n = 56) received a 0.2% chlorhexidine gluconate and amoxicillin plus clavulanic acid combination, and the third group (n = 59) received 0.09% sterile saline solution. All patients were recalled for the diagnosis of alveolar osteitis on the third and seventh postoperative days.

RESULTS

When patients in the antibiotic group were compared with those in the other 2 groups, a significant reduction in alveolar osteitis was noted (P <.05). An alteration in taste, the bad taste of the solution, and staining of dentures and oral tissues were the major complaints about chlorhexidine.

CONCLUSION

It would be more beneficial to use chlorhexidine solution with a beta-lactamase inhibitor-containing antibiotic to enhance its effectiveness for the prevention of alveolar osteitis.

Full-mouth therapy versus individual quadrant root planning: a critical commentary

BACKGROUND

This commentary compares the abilities of full-mouth disinfection (FDIS), full-mouth root planing (FRP), and partial-mouth disinfection (PDIS) to improve periodontal health. FDIS consists of 4 quadrants of root planing completed within 24 hours with adjunctive chlorhexidine therapies (e.g., rinsing, subgingival irrigation, tongue brushing). FRP denotes 4 quadrants of root planing performed within 24 hours, and PDIS refers to root planing individual quadrants of the dentition, spaced 2 weeks apart. A basic premise of administering full-mouth therapy (FDIS or FRP) is to eliminate or reduce bacterial reservoirs within the oral cavity that could inhibit optimal healing of treated sites or cause periodontal disease initiation or progression.

METHODS

Controlled clinical trials that compared the abilities of PDIS and full-mouth root planing with and without adjunctive chlorhexidine chemotherapy to alter periodontal status were reviewed.

RESULTS

Several studies conducted at one treatment center indicated that FDIS and FRP attained greater therapeutic improvements than PDIS with respect to decreasing probing depths (PD), gaining clinical attachment (CAL), diminishing bleeding upon probing, and reducing the subgingival microflora. However, the magnitude of PD reductions and gains of clinical attachment must be carefully interpreted, because initial PD measurements were usually determined after scaling and root planing, which may have caused the results to be overstated. Furthermore, in studies that addressed the utility of FDIS, it was not possible to determine if benefits induced beyond PDIS were due to FRP or administration of multifaceted intraoral chlorhexidine treatments ora combination of both therapies. One investigation that had protocol limitations indicated that similar results were attained by FRP with and without adjunctive chemotherapy. In contrast, recent studies from 2 other treatment centers indicated that there were no significant differences when the efficacy of quadrant-by-quadrant root planing was compared to FRP or FDIS with regard to PD reduction, gains of clinical attachment, and impact on the magnitude and quality of the immune response. POSSIBLE CLINICAL IMPLICATIONS: Conceptually, full-mouth therapy (FRP or FDIS) could reduce the number of patient visits and facilitate more efficient use of treatment time. In addition, there appears to be no major adverse reactions to full-mouth root planing with or without adjunctive chemotherapy. However, small study populations and non-corroborating data from different treatment centers indicate that additional randomized clinical trials are needed to determine if full-mouth therapy provides clinically relevant improvements beyond PDIS.

The effect of a polyhexamethylene biguanide mouthrinse compared to an essential oil rinse and a chlorhexidine rinse on bacterial counts and 4-day plaque regrowth

OBJECTIVES

For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% PHMB mouthwash was shown to inhibit plaque regrowth and to reduce oral bacterial counts. In this study, a 0.12% PHMB mouthrinse (A) was compared with a negative control placebo rinse (10% ethanol, flavour) (B), a positive control 0.12% chlorhexidine rinse (C), and a commercially available mouthrinse containing essential oils (Listerine) (D).

MATERIALS AND METHODS

The study was a double-blind, randomised 4-replicate 4 x 4 Latin square cross-over design in which plaque regrowth was measured. The in vivo antibacterial effect was assessed by taking bacterial counts from the tooth surface and mucosa 4 h after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. 16 volunteers participated and, on day 1 of each study period, were rendered plaque-free, ceased toothcleaning, and rinsed 2x daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. Washout periods were 9 days. Data were analysed using ANOVA with Bonferroni HSD adjustment for multiple comparisons (significance level alpha=0.05).

RESULTS

The 0.12% PHMB mouthrinse (A) was significantly more effective in inhibiting plaque than the placebo (B) but no significant differences could be observed between A and 0.12% chlorhexidine (C), or between A and Listerine (D). Bacterial count reductions on the tooth surface with PHMB (A) were significantly greater compared to the placebo (B) after 4 h and significantly greater compared to B and D after 5 days. Chlorhexidine (C) was more effective than A after 5 days. On the mucosa, chlorhexidine (C) was significantly more effective in reducing bacterial counts than the other 3 treatments at both time points investigated. PHMB (A) was significantly more effective in reducing bacterial counts than the placebo (B) after 4 h and after 5 days, and than D after 4 h.

CONCLUSION

Consistent with a previous study, a PHMB mouthrinse was shown to inhibit plaque recolonisation and to reduce oral bacterial counts, indicating that PHMB may find applications in the prevention of plaque-associated diseases.

A pilot study evaluating the safety and microbiologic efficacy of an economically viable antimicrobial lozenge in patients with head and neck cancer receiving radiation therapy

BACKGROUND

Mucositis occurs in almost all radiotherapy-treated head and neck cancer patients, in approximately 75% of patients receiving hematopoietic marrow transplantation, and in approximately 40% of all patients who receive chemotherapy. Mucositis is painful, may affect all oral functions, and is a dose- and rate-limiting toxicity of therapy for cancer. Radiation-associated mucositis (onset, intensity, and duration) has been shown in recent clinical trials to be modified by the use of antibacterial/antifungal lozenges.

PURPOSE

The aim of this collaborative two-center phase II study was to assess the toxicity and microbiologic efficacy of an economically viable antimicrobial lozenge in the management of patients receiving radiation therapy for head and neck cancer.

MATERIALS AND METHODS

Seventeen patients scheduled to receive radical or postoperative radiotherapy were provided with bacitracin, clotrimazole, and gentamicin (BCoG) lozenges (one lozenge dissolved in the mouth qid from day 1 of radiotherapy until completion). Ease of use and palatability of the lozenges, patients' symptoms (swallowing and pain), and quantitative and qualitative microbiologic evaluation of an oral rinse collection was conducted at least once weekly during radiation therapy.

RESULTS

No significant side effects were reported from the use of the lozenges. The lozenges were well tolerated at the beginning of treatment by all patients, with some minor difficulty associated with oral discomfort toward the end of the treatment. Microbiologic evaluation showed consistent elimination of yeast organisms in all patients. In four patients there was no growth of gram-negative bacilli on culture, whereas in two patients, fluctuating counts were seen, and one patient had increased counts. The remaining patients had significant reduction in the gram-negative bacilli counts.

CONCLUSIONS

This study demonstrated that the BCoG lozenge is tolerable and microbiologically efficacious, achieving elimination of Candida in all patients and reduction in gram-negative flora in most patients. A phase III study is underway to evaluate the clinical efficacy of this lozenge.

Effect of different chlorhexidine formulations in mouthrinses on de novo plaque formation

BACKGROUND

Chlorhexidine (CHX) 0.2% solution, still the golden standard as mouthrinse for the prevention of plaque formation and development of gingivitis, has some limited side-effects such as extrinsic tooth staining, poor taste, taste disturbance, sensitivity changes in tongue, pain, and the content of alcohol. These side effects led to the search of new formulations.

METHODS

In this double-blind, randomised, cross-over study, 16 young dental students with a healthy periodontium, abolished all means of mechanical plaque control during 4 experimental periods of 11 days (separated from each other by a washout period of 3 weeks). During each experimental period, they rinsed 2x daily with one of the following mouthrinses in a randomised order: CHX 0.2% + alcohol (Corsodyl), CHX 0.12% + alcohol (Perio.Aid), CHX 0.12% + sodium fluoride 0.05% (Cariax Gingival) and CHX 0.12% + CPC 0.05% (Perio.Aid, new formulation). After 7 and 11 days of undisturbed plaque formation, clinical parameters were recorded, questionnaires completed and plaque samples (supragingivally and saliva) collected.

RESULTS

The CHX 0.12% + alcohol and the CHX 0.12% + CPC 0.05% formulations were as efficient as the CHX 0.2% mouthrinse in retarding de novo plaque formation (proven by clinical observations as well as by anaerobic and aerobic culture data), and always superior (p<0.001) to the CHX 0.12% + sodium fluoride 0.05% solution. The subjective ratings were in favour of the new CHX formulation when compared with the other CHX formulations, especially for taste (p<0.05).

CONCLUSIONS

The results of this study demonstrated the potential of a new CHX 0.12% + CPC 0.05% non-alcoholic formulation as an effective anti-plaque and anti-inflammatory agent with reduced unpleasant subjective side-effects.

Effect of a polyhexamethylene biguanide mouthrinse on bacterial counts and plaque

OBJECTIVES

For various clinical applications, polyhexamethylene biguanide (PHMB) has been used for many years as an antiseptic in medicine. Little is known, however, of its antibacterial activity in the oral cavity and its ability to inhibit plaque formation. In this study, a 0.04% PHMB mouthrinse (A) was compared with a negative control placebo rinse (10% ethanol, flavour) (B) and 2 positive control chlorhexidine rinses, one of which was a 0.12% aqueous solution (C) and the other a commercially available mouthrinse (Skinsept mucosa) diluted to a chlorhexidine concentration of 0.12% (D).

MATERIAL AND METHODS

The study was a double-blind, randomised 4-replicate 4 x 4 Latin square cross-over design. Plaque regrowth was assessed with the Turesky et al. modification of the Quigley and Hein plaque index. The in vivo antibacterial effect was assessed by taking bacterial counts from the tooth surface (smears from the lingual surface of 16) and mucosa (smears from the buccal mucosa) 4 h after the 1st rinse with the preparations on day 1 and prior to the clinical examination on day 5. 16 volunteers participated, and on day 1 of each study period were rendered plaque-free, ceased toothcleaning, and rinsed 2x daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. Washout periods were 9 days. Data were analysed using ANOVA with Tukey HSD adjustment for multiple comparisons (significance level alpha=0.05).

RESULTS

Mouthrinses A, C, and D were significantly more effective in inhibiting plaque than the placebo (B). Mouthrinse C was significantly better than mouthrinses A and D, while mouthrinses D and A were equally effective in inhibiting plaque. Bacterial count reductions on the tooth surface with mouthrinse C were significantly greater compared to mouthrinse A and the placebo (B). The reduction of bacterial counts on the mucosa with C was significantly greater than with A and B after 4 h and significantly greater than with A, B and D after 5 days. Mouthrinse A reduced bacteria on the mucosa significantly more effectively than the placebo (B) after 4 h and 5 days, while mouthrinse D was more effective than the placebo (B) after 4 h.

CONCLUSION

The results indicate that a 0.04% PHMB mouthwash inhibits plaque regrowth and reduces oral bacterial counts, and may be used in preventive applications in the oral cavity.

Oral hygiene in the prevention of caries and periodontal disease

While some periodontal disease may be as old as mankind itself, caries as a public health problem appeared with the development of flour and sugar mills, and the universal access to fermentable carbohydrates. As a consequence, during the last 500 years caries and periodontal disease have been the most common diseases afflicting the human mouth. Together, these two diseases have been responsible for untold pain and suffering, and for excessive destruction and loss of people's teeth. With improving social circumstances in most industrialised nations, increased availability and affordability of modern oral health care, and the promotion of conservative treatment concepts, the 20th century saw significant progress in eliminating pain and tooth loss. Moreover, during the last 50 years advances in the oral health sciences and in technology, have not only increased our understanding of the nature of these diseases and their causes, but also introduced and tested new approaches to their prevention.

Effects of 0.12% chlorhexidine gluconate on experimental gingivitis in non-human primates: clinical and microbiological alterations

OBJECTIVE

This study examined the efficacy of 0.12% chlorhexidine gluconate (Peridex) to reduce gingival inflammation in the absence of mechanical hygiene and its effect on the oral microbial ecology in a non-human primate (NhP) model of gingivitis.

DESIGN

Twelve NhP were stratified based on existing inflammation into two groups of six NhP per group. Oral hygiene was performed on both groups so as to reach a level of gingival health (BOP < or = 0.3) at the conclusion of the hygiene phase. One group received 30 ml of 0.12% chlorhexidine gluconate twice daily 7 days/week, and a second group received 30 ml of placebo (distilled water colored to match the active) using the same regimen for 10 weeks. MEASUREMENT OUTCOMES: Clinical parameters including plaque (PLI), pocket depth (PD), attachment level (AL), and bleeding on probing (BOP) were evaluated at 2-week intervals. Subgingival plaque samples were collected by paper point at 2-week intervals and cultured for predominant cultivable bacteria.

RESULTS

By week 2, there was a difference in BOP between the groups, which reached statistical significance by week 4. This difference in BOP was maintained throughout the course of the study. Chlorhexidine gluconate (0.12%) had no significant effect on PLI, PD, or AL; although PD was greater in the placebo group after week 2 and throughout the study. Microbiologically, at week 4, the treatment group had a reduction in total bacterial counts, as well as Gram positive bacteria, and total black pigmented bacteria, compared to the placebo group. However, only the differences in Actinomyces spp. reached significance. Interestingly, when both groups received only one treatment/day on the weekends (i.e., day 6 and 7), an associated loss of statistically significant differences between the two groups was observed. Additional experiments dosing the non-human primates once daily, 5 days/week yielded no significant differences in clinical parameters, including bleeding, when compared with the placebo group.

CONCLUSION

Non-human primates provided a model system of gingivitis for testing antimicrobial agent effects on the subgingival ecology and accompanying inflammatory responses. Chlorhexidine gluconate (0.12%), even in the absence of mechanical hygiene, was effective in inhibiting clinical signs of inflammation, associated with alterations in the subgingival microbial ecology, most notably Actinomyces spp.

The importance of oral hygiene in nutritional support

Disorders of the mouth can significantly impair the quality of life of the ill patient. For patients requiring nutritional support, especially those who are unable to take food via the oral route, good oral hygiene is of prime importance. This article, the third in a series on nutrition, suggests aims and objectives for mouthcare plus an assessment tool for recording the oral state of patients on admission. The role of saliva in oral health is explored along with the problems and alleviation of a dry mouth. The current range of oral hygiene products and their use are discussed. A sound scientific knowledge of the oral environment in nurse education is advocated; it is suggested that the dental team could help to provide this.

Evaluation of oral hygiene products: science is true; don't be misled by the facts

Most people in industrialized countries use oral hygiene products. When an oral health benefit is expected, it is important that sufficient scientific evidence exist to support such claims. Ideally, data should be cumulative derived from studies in vitro and in vivo. The data should be available to the profession for evaluation by publication in refereed scientific journals. Terms and phrases require clarification, and claims made by implication or derived by inference must be avoided. Similarity in products is not necessarily proof per se of efficacy. Studies in vitro and in vivo should follow the basic principles of scientific research. Studies must be ethical, avoid bias and be suitably controlled. A choice of controls will vary depending on whether an agent or a whole product is evaluated and the development stage of a formulation. Where appropriate, new products should be compared with products already available and used by the general public. Conformity with the guidelines for good clinical practice appears to be a useful way of validating studies and a valuable guide to the profession. Studies should be designed with sufficient power to detect statistically significant differences if these exist. However, consideration must be given to the clinical significance of statistically significant differences between formulations since these are not necessarily the same. Studies in vitro provide supportive data but extrapolation to clinical effect is difficult and even misleading, and such data should not stand alone as proof of efficacy of a product. Short-term studies in vivo provide useful information, particularly at the development stage. Ideally, however, products should be proved effective when used in the circumstances for which they are developed. Nevertheless, a variety of variable influence the outcome of home-use studies, and the influence of the variable cannot usually be calculated. Although rarely considered, the cost-benefit ratio of some oral hygiene products needs to be considered.

Chlorhexidine: is it still the gold standard?

After 20 years of use by the dental profession, chlorhexidine is recognized as the gold standard against which other antiplaque and gingivitis agents are measured. Chlorhexidine's antiplaque effect is a result of the dicationic nature of the chlorhexidine molecule, which affords the agent the property of persistence of antimicrobial effect at the tooth surface, through both bactericidal and bacteriostatic effects. Although other antiplaque agents may show either purely immediate effect, or limited persistence, the degree of chlorhexidine's persistence of effect at the tooth surface is the basis of its clinical efficacy. Similarly, the cationic nature of the chlorhexidine molecule is the basis of the most common side effect associated with the use of the agent--extrinsic tooth staining. Such tooth staining seems to be the result of a local precipitation reaction between tooth-bound chlorhexidine and chromogens found within foodstuffs and beverages. The cationic nature of the chlorhexidine molecule also means that the activity of the agent is rapidly reduced in the presence of anionic agents, specifically those found within certain types of toothpaste; thus care is required when using normal toothbrushing alongside chlorhexidine. By understanding how the chemical properties of the chlorhexidine molecule can explain the plethora of clinical efficacy and safety data, the use of chlorhexidine can be optimally aimed towards the patient groups who would most benefit from the superior therapeutic effect of the agent. Specifically, chlorhexidine would seem to be of most value to patients in whom the ability to perform adequate oral hygiene procedures has been compromised. In these individuals the delivery of the correct dose of chlorhexidine to the tooth surface can be optimized through the judicial use of the several different chlorhexidine formulations now available. Thus, by understanding the properties and limitations of the chlorhexidine molecule, the dental profession can ensure that the efficacy of the agent is maximized, and the side effects associated with the agent are minimized, allowing chlorhexidine to rightly remain the gold standard against which other antiplaque agents are measured.

The comparative effect of acidified sodium chlorite and chlorhexidine mouthrinses on plaque regrowth and salivary bacterial counts

Acidified sodium chlorite (ASC) is recognised as a highly potent, broad spectrum antimicrobial system that has been successfully developed for uses in veterinary, food processing and medical device fields. The current studies aimed to investigate the persistence of antimicrobial action and plaque inhibitory properties of 3 ASC mouthrinses by comparison with positive control, chlorhexidine 0.12%, and placebo control, water, rinses. Both studies were randomised, double-blind, cross-over 5-cell designs balanced for carryover. The 1st study involved 15 healthy subjects who immediately before and at 30, 60, 180, 300 and 420 min after rinsing provided 2 ml saliva samples. The samples were immediately processed for total anaerobic bacterial counts recorded after 96 h incubation. Washout periods were a minimum of 3 days. The second study involved 20 healthy subjects who on day 1 of each study were rendered plaque free, suspended normal oral hygiene methods and commenced rinsing twice daily with the allocated rinse. On day 5, plaque was scored by index and area after disclosing with erythrosin. Washout periods were 2 1/2 days. The 3 ASC and chlorhexidine rinses produced similar reductions in salivary bacterial counts which remained significantly below the placebo control to 7 h. There were no significant differences between ASC and chlorhexidine rinses except at 30 and 60 min when significantly greater reductions were produced by 2 ASC rinses compared to the chlorhexidine rinse. Plaque indices and areas were considerably and significantly lower with the ASC and chlorhexidine rinses compared to the placebo rinse. There were no significant differences between plaque scores for the 3 ASC rinses and the chlorhexidine rinse, although for 2 ASC rinses plaque scores were lower than for the chlorhexidine rinse. The results indicate that the 3 ASC rinses have equivalent plaque inhibitory action to chlorhexidine as a rinse. Similar to chlorhexidine, the plaque inhibitory action of the rinses appears to be derived from a persistence of antimicrobial action in the mouth.

Studies on stannous fluoride toothpaste and gel (2). Effects on salivary bacterial counts and plaque regrowth in vivo

There has been a resurgence of interest in stannous fluoride (SF) products in particular to provide oral hygiene and gingival health benefits. The aim of this study was to assess the persistence of antimicrobial action of a number of SF formulations in the mouth and relate these to plaque inhibitory activity. The formulations were 2 SF toothpastes (SF1, SF2), 2 SF plus stannous pyrophosphate toothpastes (SFSP1, SFSP2), a SF gel (G), a NaF toothpaste (C) and saline (S) as control. Both studies involve 2 different groups of 21 healthy dentate volunteers. The studies were single, blind, randomised, crossover designs balanced for residual effects, with a minimum 2 1/2 day washout period. Salivary bacterial counts were determined before and to 7 h after a single rinse with the formulations. Plaque regrowth from a zero baseline (day 1) was measured by index and area on day 5, after 2x daily rinsing with slurries of the formulations or saline. For bacterial counts, highly significant treatment differences were found. Bacterial counts were variably reduced by all treatments to 30 min then showed a variable rate of return towards baseline. All test agents were significantly better than S at some timepoints. The order for greatest persistence of action downwards was; (1) SFSP2; (2) SFSP1, G, and SF1; (3) SF2; (4) C; (5) S. Highly significant differences in plaque regrowth between treatments were found with similar mean ordering of efficacy as for salivary bacterial counts from most effective downwards namely; (1) SFSP1 and SFSP2; (2) SF1; (3) SF2; G and C; (4) S. The results were consistent with a parallel study measuring tea staining in vitro, whereby formulations causing the most staining produced the greatest persistence of action and plaque inhibitory activity. This suggests the availability of stannous ions was important for the clinical effects. It is concluded that stannous ions can enhance the plaque inhibitory action of toothpaste via a persistent antimicrobial action.

The propensity of different brands of tea and coffee to cause staining associated with chlorhexidine

Dental staining is a well known and probably the most problematic side effect of using chlorhexidine oral products. Whatever mechanisms are involved, there is no doubt that cationic antiseptics, such as chlorhexidine, can precipitate or bind to surfaces anionic chromogens contained in foods and beverages. The aim of this study in vitro was to determine whether, under controlled conditions, different brands of tea or coffee varied in their propensity to cause staining associated with chlorhexidine. Optically clear acrylic specimens were cycled through saliva, chlorhexidine and different tea and coffee solutions. Staining was measured using a spectrophotometer. After 15 cycles, it was apparent that staining varied at the extreme, both within and between the tea and coffee groups. All coffee brands produced less staining than the tea brands. The least staining coffee and least staining tea brands were approximately 3x less chromogenic than the most staining equivalent beverage. Previous randomised controlled clinical trials have indicated that tea and coffee contribute to dental and tongue staining associated with chlorhexidine mouthrinses. Additionally, abstinence from tea and coffee significantly reduces staining. The results of this study in vitro suggest that when abstinence is difficult, tea and coffee brands of low chromogenicity may be recommended. Clearly these data in vitro require validation in vivo.

Full- versus partial-mouth disinfection in the treatment of periodontal infections. Long-term clinical observations of a pilot study

A classical treatment for chronic adult periodontitis consists of four to six consecutive sessions of scaling and root planing at a 1- to 2-week interval. Such a so-called "quadrant or sextant therapy" might result in a reinfection of a previously disinfected area by bacteria from an untreated region. The purpose of this study was to investigate, over an 8-month period, the clinical benefits of full-mouth disinfection within a 24-hour period in the control of chronic periodontitis. Ten adult patients with advanced chronic periodontitis were randomly assigned to a test and a control group. The control group received the standard scheme of initial periodontal therapy, consisting of scaling and root planing of the four quadrants was performed within 24 hours and immediately followed by a thorough supra- and subgingival chlorhexidine application to limit any transfer of bacteria. The latter involved tongue brushing with a 1% chlorhexidine gel for 60 seconds, mouthrinsing with a 0.2% chlorhexidine solution twice for 60 seconds, repeated subgingival irrigation of all pockets with a 1% chlorhexidine gel (3 times within 10 minutes), and mouthrinsing twice daily with a 0.2% chlorhexidine solution during 2 weeks. In addition, both groups received thorough oral hygiene instructions. The plaque index, gingival index, probing depth, gingival recession, and bleeding on probing were recorded prior to professional cleaning and at 1, 2, 4, and 8 months afterwards. Although the test group scored higher plaque indices than the control group, especially at months 2 and 4, the gingival index and bleeding tendency showed similar improvements with time. However, when the gingival/plaque ratio was considered, the latter was lower in the test group at all follow-up visits. For pockets > or = 7 mm, full-mouth disinfection showed a significantly (P = 0.01) higher reduction in probing depth at each follow-up visit with, at month 8, a reduction of 4 mm (from 8 mm to 4 mm), in comparison to 3 mm (from 8 mm to 5 mm) for the classical therapy. The increase in gingival recession in the full-mouth disinfection group remained below 0.7 mm, while in the control group it reached 1.9 mm after 8 months. This resulted in a gain of clinical attachment level of 3.7 mm for the test group versus 1.9 mm for the control group. A radiographical examination also indicated a superior improvement for the test group when compared to the control group. This pilot study suggests that a full-mouth disinfection in one day results in an improved clinical outcome in chronic periodontitis as compared to scalings per quadrant at 2-week intervals over several weeks.

Local and systemic chemotherapy in the management of periodontal disease: an opinion and review of the concept

Periodontal disease appears to arise from the interaction of pathogenic bacteria with a susceptible host. The main aims of disease management have been to establish a high standard of oral hygiene and to professionally and thoroughly debride the root surface Chemical agents could be considered for both aspects of management. Chemoprevention using supragingivally delivered agents such as chlorhexidine may be questioned for value in the pre-treatment hygiene phase but have well-established efficacy immediately preoperatively and during the post-operative weeks. Long-term maintenance use of chlorhexidine is problematic due to local side effects. Antiplaque toothpastes show modest benefits to gingivitis but are not proven to prevent recurrence of periodontitis. Chemotherapy may be directed at subgingival plaque, using antimicrobials, or at the host response using anti-inflammatory agents. Antimicrobials can be locally or systemically delivered. In most cases antimicrobial chemotherapy should be considered adjunctive to mechanical debridement. The advantages of local and systemic chemotherapy must be balanced against the disadvantages and potential side effects of agents. Antimicrobial chemotherapy offers little or no benefit to the treatment of most chronic adult periodontitis patients and should be reserved for the more rapid or refractory types of disease, and after the debridement phase. Despite the large number of studies there are insufficient comparative data to support any one local delivery system or systemic regimen as superior to another. Systemic versus local antimicrobials have not been compared to date. Host response modifying drugs such as non-steriodal anti-inflammatory drugs (NSAIDS) offer the potential to reduce breakdown and promote healing, including bone regeneration. However until more data are available, NSAIDs should not be used in the management of chronic periodontal diseases, there being no specific agent(s) or regimen established for use. Chemotherapy has an important place in the management of chronic periodontal diseases but routine use must be considered as an over prescription of these valuable agents.

The effect of oxidising mouthrinses compared with chlorhexidine on salivary bacterial counts and plaque regrowth

For various clinical indications, oxidising agents have been used in dentistry for many years. Little is known, however, of their antibacterial activity and their ability to inhibit plaque formation. In this study, 2 mouthrinses containing peroxyborate (Bocasan) and peroxycarbonate (Kavosan) were compared alongside a negative control saline rinse and a positive control chlorhexidine rinse (Corsodyl) for their ability to inhibit plaque reformation. Employing a randomised four replicate 4 x 4 latin square cross over design and, whilst omitting all other oral hygiene, plaque was measured by area and index after rinsing for 4 days. In a second study, in vivo antibacterial effects of the rinses were assessed by measuring salivary bacterial counts following single rinses with the preparations at various time intervals over 7 h. Plaque inhibition by chlorhexidine was significantly greater than the other rinses. All rinses were significantly better than the saline rinse at inhibiting plaque. For plaque area, the peroxycarbonate rinse was significantly better than the peroxyborate rinse at inhibiting plaque. Salivary bacterial count reductions were significantly greater compared to saline with chlorhexidine at all time intervals up to 7 h. Whilst both peroxyborate and peroxycarbonate rinses produced greater reductions in bacterial counts than saline up to 3 h, at no time interval were the differences significant. The findings of these studies would suggest oxidising mouthrinses may inhibit plaque formation not by a direct antibacterial effect, but by some other mechanism. The magnitude of plaque reductions obtained with the peroxyborate and more so peroxycarbonate rinses would suggest a need for further study of these preparations when used as adjuncts to normal toothbrushing.

An approach to efficacy screening of mouthrinses: studies on a group of French products (II). Inhibition of salivary bacteria and plaque in vivo

The aim of this study was to determine the value of screening studies to assess the efficacy of antiseptic mouthrinse products relative to proven products. The products tested were 6 antiseptic mouthrinses available in France. 4 contained chlorhexidine (Eludril, Hibident, Parodex and Prexidine) with Hibident considered the positive control. 1 product contained cetylpyridinium chloride (Alodont) and 1 hexetidine (Hextril). Saline was used as the negative control. The 1st study assessed the persistence of action of the products by recording salivary bacterial counts before and up to 7 h after single rinses. The 2nd study measured the inhibition of plaque regrowth, from a zero baseline, in the absence of tooth-brushing over a 4-day period. Both studies used blind randomised crossover designs balanced for residual effects. Salivary bacterial count reductions with time were highly significantly greater for Parodex to 5 h and Hibident and Prexidine to 7 h; There were no significant differences between the latter three chlorhexidine rinses except at 3 h, when decrements were significantly less with Parodex. Despite a mean trend in favour, Alodont, Eludril and Hextril were not significantly different from saline. Plaque inhibition by area and index was highly significantly different between products. Hibident, Parodex and Prexidine showed similar plaque inhibition and were significantly more effective than all other rinses. Eludril and Hextril were significantly more effective than saline but Alodont was not. Taken with the associated study in vitro and published reports on the same or similar products, it is apparent that efficacy of a product cannot be assumed merely because it contains a known active plaque inhibitor.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of polylactic acid granules on the incidence of alveolar osteitis after mandibular third molar surgery. A prospective randomized study

OBJECTIVE

To evaluate the effect of polylactic acid granules placed in third molar sockets on the incidence of alveolar osteitis.

STUDY DESIGN

A prospective randomized study with 161 patients (322 bilaterally impacted mandibular third molars).

RESULTS

The sockets in which the polylactic acid granules were placed had a significantly higher rate of alveolar osteitis (23.6%) than did the control sockets (13.58%). In all subgroups analyzed, the incidence of alveolar osteitis was higher in the experimental (polylactic acid) group.

CONCLUSION

On the basis of the findings of this study, polylactic acid granules do not reduce the incidence of alveolar osteitis and may actually contribute to a higher incidence of alveolar osteitis.

Dietary staining in vitro by mouthrinses as a comparative measure of antiseptic activity and predictor of staining in vivo

Extrinsic staining of teeth is a side-effect of some antiseptic mouthrinses. However, few of the many rinse products available to the general public have been investigated for their propensity to cause staining. Dietary factors play an aetiological role in staining and have been used in vitro to study and compare the activity of rinses. The aim of this study was to assess rinse products for staining in vitro and, through the staining reaction, to compare the activity of products containing the same ingredients. Perspex blocks, with or without saliva pretreatment, were soaked in rinses for 2 min, washed and placed in a standard tea solution for 60 min and then the optical density (OD) read on a spectrophotometer. The cycle was repeated 10 times for saliva and 17 times for no saliva specimens or until the maximum OD was exceeded. A series of three separate experiments was performed by this method. The maximum OD was not exceeded by any product before seven passages and therefore data were compared at six passages. For most products OD increased with saliva pretreatment. Some cetylpyridinium chloride (CPC) rinses stained comparably to a chlorhexidine rinse. CPC rinses, most of which contained the same concentration of the antiseptic, varied considerably in their propensity to induce staining and one was little different to water controls. A 0.1% chlorhexidine rinse stained slightly more than a 0.2%. A phenolic/essential oil product produced some staining but zinc, triclosan and other essential oil rinses did not stain.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial penetration in vitro through GTAM membrane with and without topical chlorhexidine application. A light and scanning electron microscopic study

Premature exposure of membrane in the oral cavity is considered the most common complication as well as a reason for failure or incomplete success of guided tissue regeneration, as the exposed membrane undergoes plaque accumulation. A method to control, or at least to reduce the bacterial invasion of the membrane allowing a delay in the membrane removal, could be of clinical interest. The purpose of the present study was to evaluate the possibility of treating, with topical chlorhexidine application, the bacterial colonization of exposed membranes. A special device was developed in order to evaluate, under an experimental environment, the bacterial colonization. This device was made from a removable acrylic denture base to which 5 gold cups were attached. The cups consisted of an internal compartment, isolated from the oral cavity by a GTAM membrane, and an external compartment exposed to the oral environment. 3 healthy subjects had this device fitted, bilaterally, in the molar-premolar region of the upper jaw. The cups of one side of each subject had 0.2% chlorhexidine gluconate gel applied 2x a day for 1 min, whereas those of the other side served as controls. 12 cups were removed after 2 weeks and the remainder removed after 1 month. The non-treated control specimens were characterized by greater amounts of plaque accumulation. In all the test sites, plaque deposits increased in thickness and quantity during the 4 weeks of the experiment. Complete invasion of the membrane and initial colonization of its internal surface were observed only in 4-week specimens. A relatively simple flora consisting mainly of cocci and short rods, was found in bacterial deposits forming under the influence of chlorhexidine, whereas in non-treated specimens, it was possible to observe a more mature and complex plaque, composed mostly of filamentous bacteria. In conclusion, topical application of chlorhexidine gel is an effective method of reducing plaque and calculus formation on the surface of GTAM membranes exposed to the oral cavity for up to 4 weeks. This study has, however, failed to demonstrate the capacity of chlorhexidine to prevent or to retard bacterial penetration through the thickness of the inner portion of the membranes.

Effect of chlorhexidine rinse on the incidence of dry socket in impacted mandibular third molar extraction sites

This nonrandomized prospective study was conducted in a private practice setting to determine the effect of a 0.12% chlorhexidine gluconate rinse (Peridex, Proctor and Gamble, Cincinnati, Ohio) on the incidence of dry socket after removal of impacted mandibular third molars. Over a 3-year period, 371 patients (total of 654 impacted mandibular third molars) received either no treatment (group 1), 2 weeks of twice daily Peridex rinse postsurgery (group 2), or one rinse presurgery (group 3). The group that used Peridex twice daily for 2 weeks after surgery (group 2) showed a significant reduction (56%) in the incidence of dry socket when compared with either the group that did not rinse (group 1) or the group that rinsed only once just before surgery (group 3). The incidence of dry socket was higher in smokers and in females who used oral contraceptives. Twice daily use of Peridex for 2 weeks also yielded significant reductions in dry socket in smokers, nonsmokers, and in females who did not use oral contraceptives. Results from this study demonstrate that the use of Peridex for 2 weeks after surgery is effective in prevention of dry socket after surgical extraction of impacted molars.

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.

Antioxidative activities of some chemotherapeutics. A possible mechanism in reducing gingival inflammation

Inflammatory periodontal diseases are related to dental plaque formation. Increase in the perfusion of the inflamed tissue results in increased oxygen supply. Although oxygen has healing effects, it is bound to be a mediator of peroxidation in biological membranes. Chemotherapeutic agents such as chlorhexidine, listerine, sanguinarine, and cetylpridinium chloride and oral antibiotics such as tetracycline HCl and doxycyline were tested for their antioxidative activities. While doxycycline has the highest antioxidant activity in lower volumes (0.1 ml), sanguinarine, listerine and a pace after them, tetracycline HCl, had similar effects in higher volumes (0.3 and 0.4 ml). The results showed that in addition to their antiseptic or antimicrobial effects, these preparations have an antioxidative activity against spontaneous oxidation.

The magnitude and duration of the effects of some mouthrinse products on salivary bacterial counts

The persistence of action or substantivity of an antimicrobial agent in the mouth relates to the plaque inhibitory action of that compound. Substantivity can be assessed by measuring the magnitude and duration of the fall in salivary bacteria following single rinses with antimicrobials. This was a randomised single-blind, cross-over study measuring the effects of single 60-s rinses of 5 mouthwash products on salivary bacterial counts in 14 healthy human volunteers. Effects over a 7-h period were compared with a chlorhexidine rinse product (positive control) and saline (negative control). All but one rinse, containing cetylpyridinium chloride (CPC), significantly reduced bacterial counts compared to saline up to 5-7 h. No rinse produced the magnitude or duration of effect noted for chlorhexidine and decrements from baseline, with one exception, were highly significantly lower than with the chlorhexidine product. Comparing the 2 CPC rinses, the findings suggest that the activity of one product was vitiated by some other ingredient. The triclosan/copolymer, the essential oil/phenolic and one CPC products exhibited similar persistence. In those cases where information is available, these data are consistent with comparative plaque inhibitory findings for the products or their active ingredients. Again, it is concluded that the method is a useful screening and comparison test for the potential plaque inhibitory activity of antimicrobial oral hygiene products.

Mouthrinses

Mouthrinses have been used for centuries for medicinal and cosmetic purposes, but it is only in recent years that the rationale behind the use of the ingredients has been subject to scientific research and clinical trials. Although Listerine held its position for many years in the vanguard of the anti-plaque agents, the advent of mouthrinses containing chlorhexidine was a major breakthrough in the research for a chemical means to prevent disease. Since that time, and especially in the past ten years, the number of formulations that claim to have anti-plaque, anti-calculus, and anti-caries activity has increased, and much emphasis has been placed on such substances as an adjunct to, or indeed to replace, conventional toothbrushing techniques. This review covers the literature on mouthrinses over the past five years, concentrating more on the anti-plaque, anti-gingivitis, and anti-calculus formulations. In the first section, the methods of conducting clinical trials of mouthrinses are discussed, and a plea is made for a greater degree of standardization of methodology with agreed acceptable levels of clinical benefit. Trials of established mouthrinses are considered, and the advantages and disadvantages of several newer formulations discussed. From the review, it appears that chlorhexidine has no equal in its effects on reduction of plaque and gingivitis, but major drawbacks lie in the taste and stain-producing problems. The pre-brushing rinse, Plax, does not have unqualified success in all trials, though the more recent European formulation may have promise. Newer rinses which inhibit bacterial adhesion to tooth surfaces also appear promising, and it is suggested that more work on combinations of active ingredients is necessary.

A review of chlorhexidine and its use in special populations

The purpose of this paper is to review the mechanism of the action, safety, and side-effects of chlorhexidine, and to provide guidelines for its use in special populations. Chlorhexidine has been used orally since 1959, primarily for the control of dental plaque. Chlorhexidine is a safe material, with low toxicity potential when used correctly. The most conspicuous side-effects are the development of yellow-brown stains on the teeth, tongue, and at the margins of anterior restorations, and an alteration in taste sensation. The use of chlorhexidine is indicated in developmentally disabled, medically compromised patients, and in dependent elderly populations, since these groups are often physically unable to remove plaque by mechanical means. Clinicians should not prescribe chlorhexidine indiscriminately for all patients, however, until analyzing its efficacy, safety, and side-effects.

Enhancing the effect of oral hygiene with the use of a foam brush with chlorhexidine

The maintenance of oral hygiene for hospitalized patients, particularly medically compromised and immune compromised patients, may reduce the risk of oral and systemic infection. Foam brushes have been recommended for use in these populations, however, the use of a foam brush has not been shown to be an acceptable alternative to the use of a toothbrush. In this study, we demonstrate that the use of a foam brush saturated with chlorhexidine was equally effective in measures of plaque levels and gingivitis as was the use of a toothbrush. Therefore if a toothbrush cannot be used in hospitalized patients, an alternative may be the use of chlorhexidine applied with a foam brush.

A 6-month home usage trial of a 1% chlorhexidine toothpaste (1). Effects on plaque, gingivitis, calculus and toothstaining

Research and development has been aimed towards the development of toothpastes for oral hygiene and gingival health benefits. The most effective antiplaque agent to date, chlorhexidine, is difficult to formulate into active toothpaste products. Despite some encouraging findings for experimental chlorhexidine toothpastes, there are to date no commercially available products. Based on positive findings from an experimental gingivitis study, this investigation evaluated 2 chlorhexidine toothpastes, one with fluoride, as adjuncts to oral hygiene. The study was a double-blind controlled, parallel, balanced group design, extending over 6 months. A total of 297 volunteers commenced the study after screening for a minimum acceptance level of gingivitis. At baseline, 6, 12 and 24 weeks, stain, gingival, bleeding and plaque indices were recorded, together with a calculus index at 6, 12 and 24 weeks. After a baseline prophylaxis, volunteers used the allocated product 2 x per day, with no other oral hygiene instructions given. Plaque, gingival and bleeding scores improved in all 3 groups, but to an overall significantly greater extent in the active groups. However, staining and calculus indices were significantly increased in the active compared to the control group. If the local side-effects of chlorhexidine are considered to be acceptable, these chlorhexidine toothpastes could be recommended for the same clinical applications as other chlorhexidine products. The apparent compatibility of fluoride with chlorhexidine in the one product may be pertinent to caries prevention.