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Gingival enhancement in fixed prosthodontics. Part I: Clinical findings
Gingival findings John A. Michael Thomas University
enhancement
in fixed
prosthodontics.
Part
I: Clinical
Sorensen, D.M.D.,* Frances M. Doherty, B.S.,** G. Newman, D.D.S.,*** and F. Flemmig, D.M.D.+*** of California, School of Dentistry, Los Angeles, Calif.
This study assessed the efficacy of a 0.12% chlorhexidine gluconate (CHX) rinse on the enhancement and maintenance of gingival health in patients receiving fixed prosthodontic treatment. Thirty patient participants in this examiner blind study were randomly assigned into two groups, one control and another group using CHX 15 ml b.i.d. in addition to normal oral hygiene. The medication was used for 2 weeks prior to crown preparation, 3 weeks during provisional crown placement, and 2 weeks after definitive crown cementation. Plaque and gingivitis indices were measured initially and at the three aforementioned points during the ?-week period. The plaque index for the control group decreased by 0.26 units; CHX decreased by 0.63 units at 7 weeks. The gingival index of the control group decreased by 0.37 units; CHX decreased by 0.87 units. Adjunctive use of chlorhexidine with fixed prosthodontic procedures significantly reduced plaque levels and significantly improved gingival health compared with the control patients. Fixed prosthodontic procedures alone decreased plaque levels and increased gingival health. (J PROSTHET DENT 1991;65:100-7.)
T
he procedures of tooth preparation, gingival displacement, and impression making are probably the least predictable and most frustrating procedures in restorative dentistry. Too often gingival bleeding or excessive crevicular fluid prevents hydrophobic impression materials from flowing into the sulcus below the margin of the tooth preparation. Extension of impression material into the sulcus below the preparation margin is critical for production of dies that reflect the correct emergence profile and sharp definition of the finish line.’ Ideally, periodontal health should be established before initiation of fixed prosthodontic procedures. However, in practice this safeguard is not always possible. Bleeding on stimulation or spontaneous bleeding are signs of gingival inflammation. Preoperatively, if gingival tissues bleed on probing, the manipulation of tissues during preparation, retraction, and impression procedures will induce hemor-
Presented at the Pacific Coast Society of Prosthodontists, Sun River, Ore., and the American Academy of Periodontology, San Diego, Calif. Supported in part by the Procter and Gamble Co., Cincinnati, Ohio. *Assistant Professor, Director, Graduate Prosthodontics. **Registered Dental Hygienist, St.& Research Associate, Section of Periodontics. ***Adjunct Professor, Section of Periodontics. ****Visiting Assistant Professor, Section of Periodontics. 1Ol1/25404
100
rhaging, preventing placement of impression material in the sulcus apical to the preparation of the margin. Without prior resolution of inflammation, the clinician can expect more difficult tooth preparation, gingival displacement, and impression procedures, and a poorer quality impression. In the pursuit of expediency, dentists often resort to chemical agents for control of bleeding gingival tissues during gingival retraction.2 To varying degrees hemostatic agents may be traumatic to the gingival tissues3s4and in some medically compromised patients may cause a health risk.2 To assure stability of the gingival crest during the fixed prosthodontic procedures and long term after final cementation, the treatment must be as atraumatic as possible to the soft tissues. Gingival recession, hypertrophy, or inflammation in the anterior regions can severely compromise esthetic crowns. Considerable research demonstrates the role of plaque in the etiology of gingival inflammation. If plaque development can be limited, gingival inflammation can be controlled. Gingival health can be established and maintained by mechanical and antimicrobial plaque control. Chlorhexidine gluconate (CHX) has been used as an antiplaque agent since the early 1970s in EuropeSs6and its antimicrobial efficacy is well established. It is bactericidal against gram-positive and gram-negative oral microorganisms.’ CHX is retained on tooth surfaces, pellicle substances, plaque, and mucous membranes and is released
over several hours.8l gThis phenomenon is termed substantivity
and accounts for the prolonged
JANUARY1891
in vivo antiplaque
VOLUME65
NUMBER1
GINGIVAL
Table
ENHANC:EMENT.
I.
I. CLINICAL
Study design 2 Weeks
Baseline CHX/Control Assignment to experimental
Rinse
Procedure
group
Oral hygiene instruction
Measurement
1. Clinical 2. Microbiology
effect of CHX. Its clinical safety in 2-year long-term use has been well demonstrated5 and the development of bacterial resistance has not been observed.‘O The effectiveness of CHX in reducing plaque and subsequent gingival inflammation has been well documented.5r llp l2 In view of the high efficacy of the CHX mouthrinse, the predicted theoretical advantages of using CHX in conjunction with fixed prosthodontics are easier tooth preparation, gingival displacement, and impression procedures. This would result in improved quality of the impression, gingival healing, short-term gingival health, final crown margin fidelity, and long-term gingival health. This study assessed the efficacy of rinsing with 0.12% CHX on the enhancement of gingival health in patients receiving fixed prosthodontic treatment.
MATERIAL
AND METHODS
Patients who required fixed prosthodontic treatment were recruited from the UCLA School of Dentistry. Patients were excluded from the study if they had systemic disease or consumed medications affecting the gingiva, including antibiotics, and antimicrobial or fluoride rinses 2 months before baseline. No clinical criteria were set for the gingival status of patients accepted in the study. Thirty patients were randomly assigned to either the CHX group or the control group (CON). The CHX subjects were instructed to use their usual oral hygiene procedures and then rinse with 0.12% CHX (Peridex, The Procter and Gamble Co., Cincinnati, Ohio) 15 ml b.i.d. for 30 seconds. The control group was instructed to use normal oral hygiene followed by rinsing with water for 30 seconds b.i.d. No professional scaling or prophylaxis was performed before or during the study. This examiner- and clinician-blind study was designed (Table I) with a schedule normally followed in the clinical practice of fixed prosthodontics. Measurements were made at six points around each tooth to be restored for the plaque index (Silness and Loe13) and gingival index (Loe and Silness14), and pocket depth measurements were made with a pressure sensitive periodontal probe (30 gm) (Vine Valley Research, Division of Yeaple Corp., Middlesex,
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CHXKontrol Preparation Gingival displacement Impression Provisional restoration 1. Clinical 2. Microbiology
Table 0 1 2 3
II. = = = =
6 Weeks
7 Weeks
CHX/Control
Cementation
CHX/Control Questionnaire
1. Clinical 2. Microbiology
1. Clinical 2. Microbiology
Stain intensity scale
No stain Slight overall stain (yellow color) Moderate overall stain (tan to brown color) Severe overall stain (dark brown to black color)
N.Y.). All parameters were measured at baseline, after 2 weeks at the preparation appointment, after 3 weeks at the cementation appointment, and 2 weeks after 6nal cementation. Treatment was rendered by prosthodontists who were not involved in examination of the periodontal parameters and were unaware as to patient treatment group assignment. At the beginning of each of the four treatment and examination visits, clinical photographs were made. A marginal plaque sample was retrieved from each tooth to be treated and microbiologic characterization was done.15 For each patient a maximum of two crowns were evaluated for clinical and microbiologic parameters. Every attempt was made to establish consistency in the clinical treatment procedures. A minimally traumatic tooth preparation was used. The tooth preparations were thoroughly cleaned with a cotton swab and hydrogen peroxide. The gingival displacement method used for all patients included the use of a single No. 2 retraction cord impregnated with aluminum potassium sulfate at a concentration of 0.65 mg/mch (Gingibraid, Van R Dental Products, Los Angeles, Calif.). The cord was placed dry, remained in the sulcus for 10 minutes, and was removed wet. An Aeroflow air-pressure syringe (Parke& Farmingdale, N.Y.) with a minimal-diameter orifice tip was used for the impression. Either a polyvinyl siloxane (Repros& L.D. Caulk Division, Dentsply International, Milford,Del.) orpolysul6de (Permlastic, Kerr, Romulus, Mich.) impression material was used. A combination of light- and heavy-bodied materials was used with a custom impression tray. For the fabrication of provisional restorations a poly (methyl methacrylate) acrylic resin (Jet Acrylic, Lang Dental Mfg., Chicago, Ill.) was used. Single provisional unite were directly made and
101
SORENSENETAL
I
0
Control
q
Chlorhexidine
80
60
B&line
Measurement Fig.
Table III.
7 Weeks
5 Weeks
2 Weeks
Point
1. Graph of percentage of plaque index reduction from baseline.
Summary of position of fixed restorations placed Maxillae
Group
Anterior
Control Chlorhexidine Total
Premolar
8
2
6
1
14
3
Mandible Molar
Anterior
3 2 5
2 2 4
fixed partial denture provisionals were indirectly made on a yellow stone cast made from an irreversible hydrocolloid impression. The acrylic resin restorations were adjusted and then polished with pumice slurry and Acryluster material on a 4-inch rag wheel. The provisional restorations were cemented with zinc oxide-eugenol (ZOE) temporary cement (Temp-Bond, Kerr). At the third measurement appointment, the provisional restorations were carefully removed with towel-clamp forceps and placed in 3% gluteraldehyde with phosphate buffer solution and stored for evaluation with the scanning electron microscope (SEM).15 The tooth preparation was cleaned with hydrogen peroxide on a cotton swab, the tooth was dried, and several layers of copal varnish were applied (Copalite, Cooley and Cooley, Ltd., Houston, Tex.) The crowns were cemented with zinc phosphate cement (Flecks, Mizzy Inc., Clifton Forge, Va.).
Stain grading
method
Full-arch photographs of the patients’ teeth in protruded end-to-end position were used for the determina102
Premolar
1 4 5
Molar
Total
5 9 14
21 24 45
tion of presence and degree of staining. The photographs were unmarked so as to make the measurements unbiased (blind). The baseline and final photographs were given overall scores based on the graders’ assessment of color intensity and coverage as indicated on the scale in Table II. The two photographs were then placed side by side and compared for any overall change from baseline to final visit. For statistical analysis, means and standard error of means were calculated for plaque index, gingival index, and pocket depths. A repeated measures analysis of variance and a paired t-test were used to compare intragroup and intergroup differences for time and treatment effects.
RESULTS Thirty patients were divided into two groups of 15. The CHX group had 24 teeth treated and the CON group had 21 teeth treated in the study. There were 14 women and 16 men with a mean age 39 years (range 20 to 73 years of age). The location of the fixed prostheses and the breakdown of types of restorations, new or replacement, are summarized in Tables III and IV. JANUARY
1991 VOLUME~S
NUMBERI
GINGIVAL
ENHANCIEMENT.
I. CLINICAL.
Table VI. Mean plaque index (x + SEM)
Table IV. Summary of types of restorations placed New Group
PFM
Gold
Control Chlorhexidine Total
2
I
5 7
9 16
Gold
5 3 8
2 Weeks
Baseline
Replacement PFM
T&al
7 7 14
21 24 45
Control Chlorhexidine p Value
5 Weeks
7 Weeks
0.60 f 0.07 0.58 f 0.08 0.36 + 0.07 0.34 f 0.07 0.80 + 0.11 0.48 2 0.13 0.13 f 0.04 0.17 zk 0.08 0.034
0.15
0.005
0.025
Overall treatment effect p < 0.0025.
Table V. Mean pocket depths of teeth to be restored at baseline CHX
Control Pocket
depth
(mm)
Frequency
%
1 2 3 4 5 6 7
4 54 39 21 5 1
3.2 43.2 31.2 16.8 4.0 0.8 -
8
1
0.8
Frequency
3 55 39 38 7 2 -
%
2.1 38.2 27.1 26.4 4.9 1.4 -
A review of the! baseline pocket depths of restored teeth revealed that approximately 95% of subjects in both groups had pocket depths of 4 mm or less (Tible V).
Plaque
index
At baseline the plaque indices were 0.60 for the CON group and 0.80 for the CHX group, with no statistically significant difference between groups (Table VI). The overall treatment differences were statistically significant at p < 0.0025. Significantly greater reduction in plaque levels occurred for CHX versus CON at the three follow up visits: at 2 weeks, p < 0.034; at 5 weeks, p < 0.005; and at 7 weeks, p < 0.025. The greatest reductio! in plaque index occurred by 5 weeks with mean plaque indices decreasing by 0.22 for CON and 0.35 for CHX. Fig. 1 shows the percentage of plaque reduction from baseline. A paired t-test revealed a significant reduction in the percent of plaque reduction for the CON group from baseline to 5 weeks, p < 0.01; and 7 weeks, p < 0.01. The CHX also demonstrated significant reductions in plaque from baseline at 2 weeks, p < 0.005; 5 weeks, p < 0.001; and 7 weeks, p < 0.001.
Gingival
index
At baseline the gingival indices (CON 1.31 and CHX 1.76) were statistically different. The overall treatment differences were statistically significant atp < 0.009 (Table VII). Significant differences between treatments also occurred at 5 weeks, p < 0.045, and 7 weeks, p < 0.007, with the CHX group having the greatest reduction in gingivitis. Fig. 2 demonstrates the percent&e of gingivitis reducTHE JOURNAL
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DENTISTRY
Table VII. Mean gingival index (x rt SEM) 2 Weeks
Baseline
6 Weeks
7 Weeks
Control Chlorhexidine
1.31 * 0.12 1.76 k 0.11
1.31 k 0.11 1.20 * 0.09 0.94 +I 0.11 1.59 k 0.12 1.33 k 0.08 0.89 of: 0.08
p Value
0.008
0.153
0.045
0.007
Overall treatment effect p < 0.009.
tion from baseline. A paired t-test showed a statistically significant reduction for the CON group only from baseline to 7, weeks, p < 0.01. The CHX group had significant reductions in gingival indices at all three measurement points: 2 weeks, p < 0.05; 5 weeks, p < 0.001; and 7 weeks, p < 0.001. The gingival index overall was reduced for the CON group by 0.37 or 28%) whereas for the CHX group it was reduced by 0.87 or 44 % . Most of the improvement for the’CON group occurred after cementation of the final crown (5 to 7 weeks). CHX produced 20% of the reduction in gingivitis before crown preparation, approximately 30% of the reduction during the provisional restoration phase, and 50% of the reduction after cementation of the final crown.
Pocket depth For both treatment groups no change in mean pocket depth occurred (Table VIII).
Impression
remakes
The number of impression remakes was determined, that is, the impressions that, in the clinician’s judgment, were of inadequate quality and required remaking. Six of 15 impressions had to be remade for the control group whereas none of the impressions for the CHX group required remaking.
Staining
index
Most patients in both experimental groups had at least slight staining at baseline. The control group had a higher number of patients with moderate staining and one patient with severe staining (Table IX). Table X reflects the final staining scores. At the end of the ‘/-week study period, the control and CHX groups had equal numbers in each staining level. There was a shift toward moderate staining in both groups. All subjects had at least a slight degree of staining. 103
SORENSEN
ET AL
100
__
q Control •p Chlorhexidine
60 -m
60 --
Baseline
2 Weeks
7 Weeks
5 Weeks
Measurement
Point
Fig. 2. Graph of percentage of gingival index reduction from baseline.
Mean pocket depth (mm + SEM)
Table VIII.
Baseline
Control
2.83
2 Weeks
5 Weeks
Table IX. Baseline staining levels 7 Weeks
+ 0.14 2.83 2 0.17 2.74 + 0.15 2.75 k 0.15
Chlor2.98 + 0.13 2.84 + 0.09 2.74 k 0.11 2.80 & 0.09 hexidine 0.19 0.41 0.51 p Value 0.45 overall treatment effect p < 0.32, ns.
Table XI demonstrates the overall change from baseline to final staining levels. A Mann-Whitney U test showed a significantly greater increase (p < 0.05) in staining for the CHX group. Approximately half of the control group had no change or a decrease in staining while only one subject in the CHX group had no change. Most of the CHX patients had a slight increase in stain and only one patient had a severe increase in stain. The acrylic resin provisional restorations had minimal staining during the 3-week period that they were temporarily cemented. Staining was greatest in the gingival embrasures of provisional fixed partial dentures. DISCUSSION Little research exists regarding gingival health during fixed prosthodontic procedures such as tooth preparation, gingival displacement, and impression making. The present study observed a trend for the control group toward
104
0 1
None Slight Moderate Severe Mann-Whitney
Control
Scale
Led
2 3 U test; z = -1.30
CHX
1
0
5 7
10
1
0
4
(ns, alpha = 0.05).
improved gingival health from the preparation appointment to the final measurement appointment. Most of the improvement took place after cementation of the final crown. The finding that gingival health did not deteriorate during the provisional restoration phase disagrees with several previous studies.16-18One study observed an improvement or no change in gingivar health with provisional restorations; however, the provisional restorations were present for only 1 week.lg The authors predicted higher plaque and gingival indices in the control group during the provisional restoration phase. Compared with definitive crowns, provisional restorations generally have poorer marginal fidelity and contours, greater porosity, and hence increased plaque accumulation. The debridement
and irrigation
of the sulcus during
tooth preparation, retraction cord placement, and impression making may have accounted for the decreased plaque
JANUARY
1991
VOLUME
65
NUMBER
1
GINGIVAL
ENHANCEMENT.
I. CLINICAL
Table XI.
Table X. Final st,aining levels Level
Scale
None Slight Moderate Severe
0 1 2 3
Control
CHX
0 5 8 1
Mann-Whitney U tests; z = 0 (ns, alpha = 0.05).
Overall change from baseline to final
Level
Scale
Severedecrease
-3 -2 -1 0 +1 +2 +3
Moderate decrease Slight decrease No change Slight increase Moderate increase Severe increase
Control 0 1 0 5 6 2 0
CHX 0 0 0 1 9 3 1
Mann-Whitney U test; z = 1.91 (s, alpha = 0.05, l-tailed).
indices. However, no change in gingival indices during the provisional phase was found. The 3-week cementation time for provisional restorations is adequate for accumulation of plaque.20 However, this occurred only to a minimal extent in the control group. The clinicians found that no impression remakes were required for the CHX group whereas impressions for six of control group patients had to be remade. At the 2-week period in this study, just before tooth preparation, gingival displacement, and impression procedures, there were significant differences in plaque and gingival indices between the two experimental groups. Over the first 2 weeks, there was a 40 % reduction in the plaque index for the CHX group while the control group remained unchanged. For this same time period, the gingival index significantly decreased for the CHX group and remained unchanged for the control group. For both groups there appeared to be a lag in the reduction of gingival indices. Plaque levels were reduced for the control group only during the provisional restoration phase, whereas the gingival index continued to improve beyond the provisional phase into the definitive restoration phase. Similarly, for the CHX group, while plaque levels were significantly ,reduced at the preparation appointment and provisional phase, and not after cementation of the final restorations, the gingival index continued to improve after cementation of the final restoration. Of course, a plaque index of approximately 0.2 indicates the presence of negligible amounts of plaque. Thus, this study has shown that the health of gingival tissues takes approximately 2 weeks to improve after a substantial reduction of plaque. The plaque indices for the CHX group were reduced to negligible levels; yet there were still signs for residual inflammation. The pathogenicity of the microorganisms may have been reduced and there could be a time lag in the response of the gingival tissues. Also, the resistance to plaque accumulation is considerably better for the definitive crown compared with the more porous acrylic provisional crown21 The clinician who has not established prepreparation gingival health and places esthetic crown margins based on unhealthy, edematous, or hyperplastic gingival levels may find on returning for final crown cementation that the final
THE JOURNAL
OF PBOSTHETIC
DENTISTRY
crown margin may now be exposed. Some resolution of inflammation occurs by virtue of the tooth preparation and the provisional restoration phase. Long-term gingival health and stability of the gingival margin level could also be impacted as a result of proceeding with fixed prosthodontic restoration in the presence of gingival inflammation. These considerations are based on the premise that a crown with good marginal adaptation was placed. The effect of poor prepreparation gingival health is much more obvious in the face of gingival bleeding during the retraction and impression phase. Gingival hemorrhaging during impression-making prevents adequate placement and extension of impression material in the gingival sulcus. A poor impression produces a compromised die, which propagates a poor fitting crown- further jeopardizing gingival health. It is known that the cardinal signs of gingival inflammation are redness, edema, and bleeding, and the primary etiology of gingival inflammation is the presence of local irritants initiated by the presence of plaque. If plaque accumulation and growth can be limited, gingival inflammation can be controlled.21 The present study found that preconditioning the gingival tissues with CHX mouthrinse significantly reduced plaque levels and improved gingival health compared with that of the control patients. Even though the control group patients had reduced plaque levels during the provisional phase and improved gingival health during the final crown phase, the CHX group had a significantly greater reduction in plaque levels and improvement in gingival index at each measurement point in this study. Knowing CHX’s potential to control growth of microorganisms in the oral cavity it could also be predicted that CHX would have the ability to promote wound healing for traumatic procedures in the mouth, as shown after periodontal surgery.22-24There is a great potential for trauma to the gingival tissues during the tooth preparation, gingival displacement, and impressions procedures. An overcontoured or overextended provisional or final crown restoration may cut the gingival tissues on cementation and, as a
105
SORENSENETAL
result of the overcontouring, may compromise oral hygiene measures.
A review of the staining data indicates that the CHX subjects had a greater increase in staining for the 7-week period of the study. This was expected because a number of studies have reported staining associated with CHX rinsing. However, most subjects rinsing with CHX had only a slight increase in staining over the 7-week study period. The higher overall baseline staining levels probably resulted because no preoperative prophylaxis or scaling was performed. Higher baseline levels of staining probably contributed to increasing the overall final levels of staining a8 well. Thoroughly polishing provisional restorations will help minimize staining. The clinicians observed that the greatest staining of provisional restorations took place in the gingival embrasures of fixed partial dentures. These surfaces are difficult to polish and difficult for patients to clean. To evaluate only the effects of CHX treatment, no professional scaling, root planing, or prophylaxis was .performed at any point in this study. This makes the reduction in plaque and gingival indices with the use of C%IX even more impressive. Before tooth preparation, if fixed prosthodontics patients are properly diagnosed for gingivitis and a prophylaxis or scaling is performed in conjunction with CHX rinsing, periodontal health can be optimixed, making fixed prosthodontic procedures easier and more predictable.
CLINICAL
IMPLICATIONS
This study showed that patients with bleeding on probing indicating a gingival index of 1 or greater would substantially benefit from the use of chlorhexidne. Patients with a gingival index of less than 1 would probably have less of a need for adding the drug to the regimen of prophylaxis and oral hygiene measures. Based on the findings of this study, the following g&delines are offered for the use of 0.12% chlorhexidine gluconate mouthrinse in fixed prosthodontics:, First, assessgingival health. Determine the patient’s oral hygiene abilities, pocket depths, plaque levels, and presence of gingivitis, particularly hleeding upon probing. The patient with pocket depths greater than 4 mm should first be treated or referred to a periodontist. The patient who has bleeding sites indicating a gingival index of at least 1 would benefit from the use of chlorhexidine. On the initial appointment a prophylaxis should be performed and a regimen of CHX 15 ml b.i.d. should be instituted at least 2 weeks before the fixed prosthodontic procedures. If the patient,has no bleeding sites, minimal plaque levels, or gingivitis, the use of chlorhexidine is probably not indicated. Limited benefit would be observed with a gingival index much less than 1.
106
CONCLUSIONS 1. There was a significantly greater reduction in plaque index from baseline to 7 weeks for the chlorhexidine group (79%) compared with the control group (40%). 2. There was a significantly greater reduction in gingival index from baseline to 7 weeks for the chlorhexidine group (44%) compared with the control group (28%). 3. However, some improvement in gingival health from iixed prosthodontic procedures alone was also observed.
REFERENCES 1. Shillingburg HT. Hobo S, Whitaett LD. Fundamentals of fixed prosthodontics. 2nd ed. Chicago: Quintessence Publishing Co, 1981:206. 2. Donovan TE, Gandara BK, Nemets H. Review and survey of medicamerits used with gingival retraction cords. J PRIX.THET DENT 198$533525-31. Harrison DJ. E5cct of retraction materials on the gingival sulcus epithelium. J PROSTHJTT DENT 1961;11:514-21. O’Leary TJ. Severe periodontal ilestruction following impraasion procedures. J Periodontol 1973$4:43-B. Los H, Schiott CR, Glavind L, Karring T. Two years oral uss of chlorheridine in man. I. Genera1 design and clinical effects. J Periodont Res 1976;17:135-44. 6. Flora L, Gjermo P, Rolla G, Waerhaug J. A 4-month study on the effect of chlorhexidine nouthwasheq on 56 soldiers. &and J Dent Res 1972;80:10-7. I. Baker PJ, Coburn RA, Genco PJ, Evans RT. Structural determinants of activity of chlorhexidine and alkyl bisbiguanidas against the human oral flora. J Dent Ras 1987;66:1699-106. for hydroxy8. Rolla G. Loe H, Schiott CR. The affinity of chlorhesidine apatite and salivary mucins. J Periodont Ras 1970;5:90-5. 9. Rolls G, Los H, Schiott CR. Retention of chlorhexidine in the human oral cavity. Arch Oral Biol 1971;16:1109-16. 10. Briner WW, Grossman E, Buckner RY, et al. Effect of chlorheridine gluconate mouthrinse on plaque bacterial. J Periodont Res 198621 (Suppl):44-52. 11. Siegrist AE, Gusbarti FA, Breu ML, Weber HP, Lang NP. Efficacy of supervised rinsing with chlorhexidine digluconate in comparison to phenolic and piant alkaloid .compounds. J Periodont Res 1986; 16(Suppl):60-73. 12. Grossman E, Rieter D, Stursenbarger OP, et al. Six-month study on the effect of a chlorhexidine mouthrinse on gingivitis in adults. J Periodont Res 1986;16(Suppl):33-43. 13. Silness J, Loe H. Periodontal disease in pregnancy. II. Correlation between oral hygiene and periodontal condition, Acta Odontol &and 1964;22:121-35. 14. Loe H, Silness J. Periodontal disease in pregnancy. I. Prevalence and severity. Acta Odontol Stand 1963;21:533-51. 15. Flemming TF, Sorensen JA, Newman MG, Nachnani S. Gingival enhancement in fixed prosthodontics. II. Microbiologic findings. J PROWHET D~UVT 199Otin press). 16. Donaldson D. GingivaI recession associated with temporary crowns. J Periodontol 1973;44:691-6. 17. Waerhaug J. Zander HA. Reaction of gingival tissues to self-curing acrylic restorations. J Am Dent ABBOC 1957$4:760-B. 18. Brandau HE, Yaman P, Molvar M. Effect of rastorative procedures for a porcelain jacket crown on gingival health and height. Am J Dent 1988;1:119-22. des marginalen paro19. Siebert GK. Heiman H. Zum entsunddungsgrad dontiumsauf reise von provisorischen Kronen. Eine khnisch-experimentelle studie. Dtsch Zahnaritl Z 1986;41:986-988. gingivitis in man II. 20. Theilade E, Wright WH, Jensen SE. Experimental A longitudinal, clinical and bacteriological investigation. J Periodont Res 1966;1:1-13. properties 21. Sorensen J. A rationale for comparison of plaque-retaining of crown systems. J PROSTHET DENT 1989:62:264-g.
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22. Langabaek J, Bay L. The effect of chlorhexidine mouthrinse on healing after gingivectomy. Stand J Dent Res 1976;&1:224-8. 23. Sam M, Newman hY(G,Anderson L, Matoska W, Otomo-Corgel J, Saltini C. Clinical enhancement of post-periodontal surgical therapy by a 0.12% chlorhexidine gluconate mouthrinse. J Periodontol 1989;60: 570-6. 24. Newman MG, Sam M, Nachnani S, Saltini C, Anderson L. Effect of 0.12% chlorhexidine on bacterial recolonization following periodontal surgery. J Periodontol 1989;60:577-81.
Contributing
author D.D.S., Adjunct Assistant Professor, Department of Biostatistics, School of Public Health, University of California, Los Angeles, Calif.
J. J. Lee, PLD,
Reprint requests to: DR. JOHN A. SORENSEN CHS 33-041 SCHOOL OF DENTISTRY UNIVEFWTY OF CALIFORNIA Los ANGELES. CA 90024
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TEE
JOURNAL
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PROSTHETIC
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107
enhancement
in fixed
prosthodontics.
Part
I: Clinical
Sorensen, D.M.D.,* Frances M. Doherty, B.S.,** G. Newman, D.D.S.,*** and F. Flemmig, D.M.D.+*** of California, School of Dentistry, Los Angeles, Calif.
This study assessed the efficacy of a 0.12% chlorhexidine gluconate (CHX) rinse on the enhancement and maintenance of gingival health in patients receiving fixed prosthodontic treatment. Thirty patient participants in this examiner blind study were randomly assigned into two groups, one control and another group using CHX 15 ml b.i.d. in addition to normal oral hygiene. The medication was used for 2 weeks prior to crown preparation, 3 weeks during provisional crown placement, and 2 weeks after definitive crown cementation. Plaque and gingivitis indices were measured initially and at the three aforementioned points during the ?-week period. The plaque index for the control group decreased by 0.26 units; CHX decreased by 0.63 units at 7 weeks. The gingival index of the control group decreased by 0.37 units; CHX decreased by 0.87 units. Adjunctive use of chlorhexidine with fixed prosthodontic procedures significantly reduced plaque levels and significantly improved gingival health compared with the control patients. Fixed prosthodontic procedures alone decreased plaque levels and increased gingival health. (J PROSTHET DENT 1991;65:100-7.)
T
he procedures of tooth preparation, gingival displacement, and impression making are probably the least predictable and most frustrating procedures in restorative dentistry. Too often gingival bleeding or excessive crevicular fluid prevents hydrophobic impression materials from flowing into the sulcus below the margin of the tooth preparation. Extension of impression material into the sulcus below the preparation margin is critical for production of dies that reflect the correct emergence profile and sharp definition of the finish line.’ Ideally, periodontal health should be established before initiation of fixed prosthodontic procedures. However, in practice this safeguard is not always possible. Bleeding on stimulation or spontaneous bleeding are signs of gingival inflammation. Preoperatively, if gingival tissues bleed on probing, the manipulation of tissues during preparation, retraction, and impression procedures will induce hemor-
Presented at the Pacific Coast Society of Prosthodontists, Sun River, Ore., and the American Academy of Periodontology, San Diego, Calif. Supported in part by the Procter and Gamble Co., Cincinnati, Ohio. *Assistant Professor, Director, Graduate Prosthodontics. **Registered Dental Hygienist, St.& Research Associate, Section of Periodontics. ***Adjunct Professor, Section of Periodontics. ****Visiting Assistant Professor, Section of Periodontics. 1Ol1/25404
100
rhaging, preventing placement of impression material in the sulcus apical to the preparation of the margin. Without prior resolution of inflammation, the clinician can expect more difficult tooth preparation, gingival displacement, and impression procedures, and a poorer quality impression. In the pursuit of expediency, dentists often resort to chemical agents for control of bleeding gingival tissues during gingival retraction.2 To varying degrees hemostatic agents may be traumatic to the gingival tissues3s4and in some medically compromised patients may cause a health risk.2 To assure stability of the gingival crest during the fixed prosthodontic procedures and long term after final cementation, the treatment must be as atraumatic as possible to the soft tissues. Gingival recession, hypertrophy, or inflammation in the anterior regions can severely compromise esthetic crowns. Considerable research demonstrates the role of plaque in the etiology of gingival inflammation. If plaque development can be limited, gingival inflammation can be controlled. Gingival health can be established and maintained by mechanical and antimicrobial plaque control. Chlorhexidine gluconate (CHX) has been used as an antiplaque agent since the early 1970s in EuropeSs6and its antimicrobial efficacy is well established. It is bactericidal against gram-positive and gram-negative oral microorganisms.’ CHX is retained on tooth surfaces, pellicle substances, plaque, and mucous membranes and is released
over several hours.8l gThis phenomenon is termed substantivity
and accounts for the prolonged
JANUARY1891
in vivo antiplaque
VOLUME65
NUMBER1
GINGIVAL
Table
ENHANC:EMENT.
I.
I. CLINICAL
Study design 2 Weeks
Baseline CHX/Control Assignment to experimental
Rinse
Procedure
group
Oral hygiene instruction
Measurement
1. Clinical 2. Microbiology
effect of CHX. Its clinical safety in 2-year long-term use has been well demonstrated5 and the development of bacterial resistance has not been observed.‘O The effectiveness of CHX in reducing plaque and subsequent gingival inflammation has been well documented.5r llp l2 In view of the high efficacy of the CHX mouthrinse, the predicted theoretical advantages of using CHX in conjunction with fixed prosthodontics are easier tooth preparation, gingival displacement, and impression procedures. This would result in improved quality of the impression, gingival healing, short-term gingival health, final crown margin fidelity, and long-term gingival health. This study assessed the efficacy of rinsing with 0.12% CHX on the enhancement of gingival health in patients receiving fixed prosthodontic treatment.
MATERIAL
AND METHODS
Patients who required fixed prosthodontic treatment were recruited from the UCLA School of Dentistry. Patients were excluded from the study if they had systemic disease or consumed medications affecting the gingiva, including antibiotics, and antimicrobial or fluoride rinses 2 months before baseline. No clinical criteria were set for the gingival status of patients accepted in the study. Thirty patients were randomly assigned to either the CHX group or the control group (CON). The CHX subjects were instructed to use their usual oral hygiene procedures and then rinse with 0.12% CHX (Peridex, The Procter and Gamble Co., Cincinnati, Ohio) 15 ml b.i.d. for 30 seconds. The control group was instructed to use normal oral hygiene followed by rinsing with water for 30 seconds b.i.d. No professional scaling or prophylaxis was performed before or during the study. This examiner- and clinician-blind study was designed (Table I) with a schedule normally followed in the clinical practice of fixed prosthodontics. Measurements were made at six points around each tooth to be restored for the plaque index (Silness and Loe13) and gingival index (Loe and Silness14), and pocket depth measurements were made with a pressure sensitive periodontal probe (30 gm) (Vine Valley Research, Division of Yeaple Corp., Middlesex,
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CHXKontrol Preparation Gingival displacement Impression Provisional restoration 1. Clinical 2. Microbiology
Table 0 1 2 3
II. = = = =
6 Weeks
7 Weeks
CHX/Control
Cementation
CHX/Control Questionnaire
1. Clinical 2. Microbiology
1. Clinical 2. Microbiology
Stain intensity scale
No stain Slight overall stain (yellow color) Moderate overall stain (tan to brown color) Severe overall stain (dark brown to black color)
N.Y.). All parameters were measured at baseline, after 2 weeks at the preparation appointment, after 3 weeks at the cementation appointment, and 2 weeks after 6nal cementation. Treatment was rendered by prosthodontists who were not involved in examination of the periodontal parameters and were unaware as to patient treatment group assignment. At the beginning of each of the four treatment and examination visits, clinical photographs were made. A marginal plaque sample was retrieved from each tooth to be treated and microbiologic characterization was done.15 For each patient a maximum of two crowns were evaluated for clinical and microbiologic parameters. Every attempt was made to establish consistency in the clinical treatment procedures. A minimally traumatic tooth preparation was used. The tooth preparations were thoroughly cleaned with a cotton swab and hydrogen peroxide. The gingival displacement method used for all patients included the use of a single No. 2 retraction cord impregnated with aluminum potassium sulfate at a concentration of 0.65 mg/mch (Gingibraid, Van R Dental Products, Los Angeles, Calif.). The cord was placed dry, remained in the sulcus for 10 minutes, and was removed wet. An Aeroflow air-pressure syringe (Parke& Farmingdale, N.Y.) with a minimal-diameter orifice tip was used for the impression. Either a polyvinyl siloxane (Repros& L.D. Caulk Division, Dentsply International, Milford,Del.) orpolysul6de (Permlastic, Kerr, Romulus, Mich.) impression material was used. A combination of light- and heavy-bodied materials was used with a custom impression tray. For the fabrication of provisional restorations a poly (methyl methacrylate) acrylic resin (Jet Acrylic, Lang Dental Mfg., Chicago, Ill.) was used. Single provisional unite were directly made and
101
SORENSENETAL
I
0
Control
q
Chlorhexidine
80
60
B&line
Measurement Fig.
Table III.
7 Weeks
5 Weeks
2 Weeks
Point
1. Graph of percentage of plaque index reduction from baseline.
Summary of position of fixed restorations placed Maxillae
Group
Anterior
Control Chlorhexidine Total
Premolar
8
2
6
1
14
3
Mandible Molar
Anterior
3 2 5
2 2 4
fixed partial denture provisionals were indirectly made on a yellow stone cast made from an irreversible hydrocolloid impression. The acrylic resin restorations were adjusted and then polished with pumice slurry and Acryluster material on a 4-inch rag wheel. The provisional restorations were cemented with zinc oxide-eugenol (ZOE) temporary cement (Temp-Bond, Kerr). At the third measurement appointment, the provisional restorations were carefully removed with towel-clamp forceps and placed in 3% gluteraldehyde with phosphate buffer solution and stored for evaluation with the scanning electron microscope (SEM).15 The tooth preparation was cleaned with hydrogen peroxide on a cotton swab, the tooth was dried, and several layers of copal varnish were applied (Copalite, Cooley and Cooley, Ltd., Houston, Tex.) The crowns were cemented with zinc phosphate cement (Flecks, Mizzy Inc., Clifton Forge, Va.).
Stain grading
method
Full-arch photographs of the patients’ teeth in protruded end-to-end position were used for the determina102
Premolar
1 4 5
Molar
Total
5 9 14
21 24 45
tion of presence and degree of staining. The photographs were unmarked so as to make the measurements unbiased (blind). The baseline and final photographs were given overall scores based on the graders’ assessment of color intensity and coverage as indicated on the scale in Table II. The two photographs were then placed side by side and compared for any overall change from baseline to final visit. For statistical analysis, means and standard error of means were calculated for plaque index, gingival index, and pocket depths. A repeated measures analysis of variance and a paired t-test were used to compare intragroup and intergroup differences for time and treatment effects.
RESULTS Thirty patients were divided into two groups of 15. The CHX group had 24 teeth treated and the CON group had 21 teeth treated in the study. There were 14 women and 16 men with a mean age 39 years (range 20 to 73 years of age). The location of the fixed prostheses and the breakdown of types of restorations, new or replacement, are summarized in Tables III and IV. JANUARY
1991 VOLUME~S
NUMBERI
GINGIVAL
ENHANCIEMENT.
I. CLINICAL.
Table VI. Mean plaque index (x + SEM)
Table IV. Summary of types of restorations placed New Group
PFM
Gold
Control Chlorhexidine Total
2
I
5 7
9 16
Gold
5 3 8
2 Weeks
Baseline
Replacement PFM
T&al
7 7 14
21 24 45
Control Chlorhexidine p Value
5 Weeks
7 Weeks
0.60 f 0.07 0.58 f 0.08 0.36 + 0.07 0.34 f 0.07 0.80 + 0.11 0.48 2 0.13 0.13 f 0.04 0.17 zk 0.08 0.034
0.15
0.005
0.025
Overall treatment effect p < 0.0025.
Table V. Mean pocket depths of teeth to be restored at baseline CHX
Control Pocket
depth
(mm)
Frequency
%
1 2 3 4 5 6 7
4 54 39 21 5 1
3.2 43.2 31.2 16.8 4.0 0.8 -
8
1
0.8
Frequency
3 55 39 38 7 2 -
%
2.1 38.2 27.1 26.4 4.9 1.4 -
A review of the! baseline pocket depths of restored teeth revealed that approximately 95% of subjects in both groups had pocket depths of 4 mm or less (Tible V).
Plaque
index
At baseline the plaque indices were 0.60 for the CON group and 0.80 for the CHX group, with no statistically significant difference between groups (Table VI). The overall treatment differences were statistically significant at p < 0.0025. Significantly greater reduction in plaque levels occurred for CHX versus CON at the three follow up visits: at 2 weeks, p < 0.034; at 5 weeks, p < 0.005; and at 7 weeks, p < 0.025. The greatest reductio! in plaque index occurred by 5 weeks with mean plaque indices decreasing by 0.22 for CON and 0.35 for CHX. Fig. 1 shows the percentage of plaque reduction from baseline. A paired t-test revealed a significant reduction in the percent of plaque reduction for the CON group from baseline to 5 weeks, p < 0.01; and 7 weeks, p < 0.01. The CHX also demonstrated significant reductions in plaque from baseline at 2 weeks, p < 0.005; 5 weeks, p < 0.001; and 7 weeks, p < 0.001.
Gingival
index
At baseline the gingival indices (CON 1.31 and CHX 1.76) were statistically different. The overall treatment differences were statistically significant atp < 0.009 (Table VII). Significant differences between treatments also occurred at 5 weeks, p < 0.045, and 7 weeks, p < 0.007, with the CHX group having the greatest reduction in gingivitis. Fig. 2 demonstrates the percent&e of gingivitis reducTHE JOURNAL
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Table VII. Mean gingival index (x rt SEM) 2 Weeks
Baseline
6 Weeks
7 Weeks
Control Chlorhexidine
1.31 * 0.12 1.76 k 0.11
1.31 k 0.11 1.20 * 0.09 0.94 +I 0.11 1.59 k 0.12 1.33 k 0.08 0.89 of: 0.08
p Value
0.008
0.153
0.045
0.007
Overall treatment effect p < 0.009.
tion from baseline. A paired t-test showed a statistically significant reduction for the CON group only from baseline to 7, weeks, p < 0.01. The CHX group had significant reductions in gingival indices at all three measurement points: 2 weeks, p < 0.05; 5 weeks, p < 0.001; and 7 weeks, p < 0.001. The gingival index overall was reduced for the CON group by 0.37 or 28%) whereas for the CHX group it was reduced by 0.87 or 44 % . Most of the improvement for the’CON group occurred after cementation of the final crown (5 to 7 weeks). CHX produced 20% of the reduction in gingivitis before crown preparation, approximately 30% of the reduction during the provisional restoration phase, and 50% of the reduction after cementation of the final crown.
Pocket depth For both treatment groups no change in mean pocket depth occurred (Table VIII).
Impression
remakes
The number of impression remakes was determined, that is, the impressions that, in the clinician’s judgment, were of inadequate quality and required remaking. Six of 15 impressions had to be remade for the control group whereas none of the impressions for the CHX group required remaking.
Staining
index
Most patients in both experimental groups had at least slight staining at baseline. The control group had a higher number of patients with moderate staining and one patient with severe staining (Table IX). Table X reflects the final staining scores. At the end of the ‘/-week study period, the control and CHX groups had equal numbers in each staining level. There was a shift toward moderate staining in both groups. All subjects had at least a slight degree of staining. 103
SORENSEN
ET AL
100
__
q Control •p Chlorhexidine
60 -m
60 --
Baseline
2 Weeks
7 Weeks
5 Weeks
Measurement
Point
Fig. 2. Graph of percentage of gingival index reduction from baseline.
Mean pocket depth (mm + SEM)
Table VIII.
Baseline
Control
2.83
2 Weeks
5 Weeks
Table IX. Baseline staining levels 7 Weeks
+ 0.14 2.83 2 0.17 2.74 + 0.15 2.75 k 0.15
Chlor2.98 + 0.13 2.84 + 0.09 2.74 k 0.11 2.80 & 0.09 hexidine 0.19 0.41 0.51 p Value 0.45 overall treatment effect p < 0.32, ns.
Table XI demonstrates the overall change from baseline to final staining levels. A Mann-Whitney U test showed a significantly greater increase (p < 0.05) in staining for the CHX group. Approximately half of the control group had no change or a decrease in staining while only one subject in the CHX group had no change. Most of the CHX patients had a slight increase in stain and only one patient had a severe increase in stain. The acrylic resin provisional restorations had minimal staining during the 3-week period that they were temporarily cemented. Staining was greatest in the gingival embrasures of provisional fixed partial dentures. DISCUSSION Little research exists regarding gingival health during fixed prosthodontic procedures such as tooth preparation, gingival displacement, and impression making. The present study observed a trend for the control group toward
104
0 1
None Slight Moderate Severe Mann-Whitney
Control
Scale
Led
2 3 U test; z = -1.30
CHX
1
0
5 7
10
1
0
4
(ns, alpha = 0.05).
improved gingival health from the preparation appointment to the final measurement appointment. Most of the improvement took place after cementation of the final crown. The finding that gingival health did not deteriorate during the provisional restoration phase disagrees with several previous studies.16-18One study observed an improvement or no change in gingivar health with provisional restorations; however, the provisional restorations were present for only 1 week.lg The authors predicted higher plaque and gingival indices in the control group during the provisional restoration phase. Compared with definitive crowns, provisional restorations generally have poorer marginal fidelity and contours, greater porosity, and hence increased plaque accumulation. The debridement
and irrigation
of the sulcus during
tooth preparation, retraction cord placement, and impression making may have accounted for the decreased plaque
JANUARY
1991
VOLUME
65
NUMBER
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GINGIVAL
ENHANCEMENT.
I. CLINICAL
Table XI.
Table X. Final st,aining levels Level
Scale
None Slight Moderate Severe
0 1 2 3
Control
CHX
0 5 8 1
Mann-Whitney U tests; z = 0 (ns, alpha = 0.05).
Overall change from baseline to final
Level
Scale
Severedecrease
-3 -2 -1 0 +1 +2 +3
Moderate decrease Slight decrease No change Slight increase Moderate increase Severe increase
Control 0 1 0 5 6 2 0
CHX 0 0 0 1 9 3 1
Mann-Whitney U test; z = 1.91 (s, alpha = 0.05, l-tailed).
indices. However, no change in gingival indices during the provisional phase was found. The 3-week cementation time for provisional restorations is adequate for accumulation of plaque.20 However, this occurred only to a minimal extent in the control group. The clinicians found that no impression remakes were required for the CHX group whereas impressions for six of control group patients had to be remade. At the 2-week period in this study, just before tooth preparation, gingival displacement, and impression procedures, there were significant differences in plaque and gingival indices between the two experimental groups. Over the first 2 weeks, there was a 40 % reduction in the plaque index for the CHX group while the control group remained unchanged. For this same time period, the gingival index significantly decreased for the CHX group and remained unchanged for the control group. For both groups there appeared to be a lag in the reduction of gingival indices. Plaque levels were reduced for the control group only during the provisional restoration phase, whereas the gingival index continued to improve beyond the provisional phase into the definitive restoration phase. Similarly, for the CHX group, while plaque levels were significantly ,reduced at the preparation appointment and provisional phase, and not after cementation of the final restorations, the gingival index continued to improve after cementation of the final restoration. Of course, a plaque index of approximately 0.2 indicates the presence of negligible amounts of plaque. Thus, this study has shown that the health of gingival tissues takes approximately 2 weeks to improve after a substantial reduction of plaque. The plaque indices for the CHX group were reduced to negligible levels; yet there were still signs for residual inflammation. The pathogenicity of the microorganisms may have been reduced and there could be a time lag in the response of the gingival tissues. Also, the resistance to plaque accumulation is considerably better for the definitive crown compared with the more porous acrylic provisional crown21 The clinician who has not established prepreparation gingival health and places esthetic crown margins based on unhealthy, edematous, or hyperplastic gingival levels may find on returning for final crown cementation that the final
THE JOURNAL
OF PBOSTHETIC
DENTISTRY
crown margin may now be exposed. Some resolution of inflammation occurs by virtue of the tooth preparation and the provisional restoration phase. Long-term gingival health and stability of the gingival margin level could also be impacted as a result of proceeding with fixed prosthodontic restoration in the presence of gingival inflammation. These considerations are based on the premise that a crown with good marginal adaptation was placed. The effect of poor prepreparation gingival health is much more obvious in the face of gingival bleeding during the retraction and impression phase. Gingival hemorrhaging during impression-making prevents adequate placement and extension of impression material in the gingival sulcus. A poor impression produces a compromised die, which propagates a poor fitting crown- further jeopardizing gingival health. It is known that the cardinal signs of gingival inflammation are redness, edema, and bleeding, and the primary etiology of gingival inflammation is the presence of local irritants initiated by the presence of plaque. If plaque accumulation and growth can be limited, gingival inflammation can be controlled.21 The present study found that preconditioning the gingival tissues with CHX mouthrinse significantly reduced plaque levels and improved gingival health compared with that of the control patients. Even though the control group patients had reduced plaque levels during the provisional phase and improved gingival health during the final crown phase, the CHX group had a significantly greater reduction in plaque levels and improvement in gingival index at each measurement point in this study. Knowing CHX’s potential to control growth of microorganisms in the oral cavity it could also be predicted that CHX would have the ability to promote wound healing for traumatic procedures in the mouth, as shown after periodontal surgery.22-24There is a great potential for trauma to the gingival tissues during the tooth preparation, gingival displacement, and impressions procedures. An overcontoured or overextended provisional or final crown restoration may cut the gingival tissues on cementation and, as a
105
SORENSENETAL
result of the overcontouring, may compromise oral hygiene measures.
A review of the staining data indicates that the CHX subjects had a greater increase in staining for the 7-week period of the study. This was expected because a number of studies have reported staining associated with CHX rinsing. However, most subjects rinsing with CHX had only a slight increase in staining over the 7-week study period. The higher overall baseline staining levels probably resulted because no preoperative prophylaxis or scaling was performed. Higher baseline levels of staining probably contributed to increasing the overall final levels of staining a8 well. Thoroughly polishing provisional restorations will help minimize staining. The clinicians observed that the greatest staining of provisional restorations took place in the gingival embrasures of fixed partial dentures. These surfaces are difficult to polish and difficult for patients to clean. To evaluate only the effects of CHX treatment, no professional scaling, root planing, or prophylaxis was .performed at any point in this study. This makes the reduction in plaque and gingival indices with the use of C%IX even more impressive. Before tooth preparation, if fixed prosthodontics patients are properly diagnosed for gingivitis and a prophylaxis or scaling is performed in conjunction with CHX rinsing, periodontal health can be optimixed, making fixed prosthodontic procedures easier and more predictable.
CLINICAL
IMPLICATIONS
This study showed that patients with bleeding on probing indicating a gingival index of 1 or greater would substantially benefit from the use of chlorhexidne. Patients with a gingival index of less than 1 would probably have less of a need for adding the drug to the regimen of prophylaxis and oral hygiene measures. Based on the findings of this study, the following g&delines are offered for the use of 0.12% chlorhexidine gluconate mouthrinse in fixed prosthodontics:, First, assessgingival health. Determine the patient’s oral hygiene abilities, pocket depths, plaque levels, and presence of gingivitis, particularly hleeding upon probing. The patient with pocket depths greater than 4 mm should first be treated or referred to a periodontist. The patient who has bleeding sites indicating a gingival index of at least 1 would benefit from the use of chlorhexidine. On the initial appointment a prophylaxis should be performed and a regimen of CHX 15 ml b.i.d. should be instituted at least 2 weeks before the fixed prosthodontic procedures. If the patient,has no bleeding sites, minimal plaque levels, or gingivitis, the use of chlorhexidine is probably not indicated. Limited benefit would be observed with a gingival index much less than 1.
106
CONCLUSIONS 1. There was a significantly greater reduction in plaque index from baseline to 7 weeks for the chlorhexidine group (79%) compared with the control group (40%). 2. There was a significantly greater reduction in gingival index from baseline to 7 weeks for the chlorhexidine group (44%) compared with the control group (28%). 3. However, some improvement in gingival health from iixed prosthodontic procedures alone was also observed.
REFERENCES 1. Shillingburg HT. Hobo S, Whitaett LD. Fundamentals of fixed prosthodontics. 2nd ed. Chicago: Quintessence Publishing Co, 1981:206. 2. Donovan TE, Gandara BK, Nemets H. Review and survey of medicamerits used with gingival retraction cords. J PRIX.THET DENT 198$533525-31. Harrison DJ. E5cct of retraction materials on the gingival sulcus epithelium. J PROSTHJTT DENT 1961;11:514-21. O’Leary TJ. Severe periodontal ilestruction following impraasion procedures. J Periodontol 1973$4:43-B. Los H, Schiott CR, Glavind L, Karring T. Two years oral uss of chlorheridine in man. I. Genera1 design and clinical effects. J Periodont Res 1976;17:135-44. 6. Flora L, Gjermo P, Rolla G, Waerhaug J. A 4-month study on the effect of chlorhexidine nouthwasheq on 56 soldiers. &and J Dent Res 1972;80:10-7. I. Baker PJ, Coburn RA, Genco PJ, Evans RT. Structural determinants of activity of chlorhexidine and alkyl bisbiguanidas against the human oral flora. J Dent Ras 1987;66:1699-106. for hydroxy8. Rolla G. Loe H, Schiott CR. The affinity of chlorhesidine apatite and salivary mucins. J Periodont Ras 1970;5:90-5. 9. Rolls G, Los H, Schiott CR. Retention of chlorhexidine in the human oral cavity. Arch Oral Biol 1971;16:1109-16. 10. Briner WW, Grossman E, Buckner RY, et al. Effect of chlorheridine gluconate mouthrinse on plaque bacterial. J Periodont Res 198621 (Suppl):44-52. 11. Siegrist AE, Gusbarti FA, Breu ML, Weber HP, Lang NP. Efficacy of supervised rinsing with chlorhexidine digluconate in comparison to phenolic and piant alkaloid .compounds. J Periodont Res 1986; 16(Suppl):60-73. 12. Grossman E, Rieter D, Stursenbarger OP, et al. Six-month study on the effect of a chlorhexidine mouthrinse on gingivitis in adults. J Periodont Res 1986;16(Suppl):33-43. 13. Silness J, Loe H. Periodontal disease in pregnancy. II. Correlation between oral hygiene and periodontal condition, Acta Odontol &and 1964;22:121-35. 14. Loe H, Silness J. Periodontal disease in pregnancy. I. Prevalence and severity. Acta Odontol Stand 1963;21:533-51. 15. Flemming TF, Sorensen JA, Newman MG, Nachnani S. Gingival enhancement in fixed prosthodontics. II. Microbiologic findings. J PROWHET D~UVT 199Otin press). 16. Donaldson D. GingivaI recession associated with temporary crowns. J Periodontol 1973;44:691-6. 17. Waerhaug J. Zander HA. Reaction of gingival tissues to self-curing acrylic restorations. J Am Dent ABBOC 1957$4:760-B. 18. Brandau HE, Yaman P, Molvar M. Effect of rastorative procedures for a porcelain jacket crown on gingival health and height. Am J Dent 1988;1:119-22. des marginalen paro19. Siebert GK. Heiman H. Zum entsunddungsgrad dontiumsauf reise von provisorischen Kronen. Eine khnisch-experimentelle studie. Dtsch Zahnaritl Z 1986;41:986-988. gingivitis in man II. 20. Theilade E, Wright WH, Jensen SE. Experimental A longitudinal, clinical and bacteriological investigation. J Periodont Res 1966;1:1-13. properties 21. Sorensen J. A rationale for comparison of plaque-retaining of crown systems. J PROSTHET DENT 1989:62:264-g.
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22. Langabaek J, Bay L. The effect of chlorhexidine mouthrinse on healing after gingivectomy. Stand J Dent Res 1976;&1:224-8. 23. Sam M, Newman hY(G,Anderson L, Matoska W, Otomo-Corgel J, Saltini C. Clinical enhancement of post-periodontal surgical therapy by a 0.12% chlorhexidine gluconate mouthrinse. J Periodontol 1989;60: 570-6. 24. Newman MG, Sam M, Nachnani S, Saltini C, Anderson L. Effect of 0.12% chlorhexidine on bacterial recolonization following periodontal surgery. J Periodontol 1989;60:577-81.
Contributing
author D.D.S., Adjunct Assistant Professor, Department of Biostatistics, School of Public Health, University of California, Los Angeles, Calif.
J. J. Lee, PLD,
Reprint requests to: DR. JOHN A. SORENSEN CHS 33-041 SCHOOL OF DENTISTRY UNIVEFWTY OF CALIFORNIA Los ANGELES. CA 90024
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