Papilla healing following sulcular full thickness flap in endodontic surgery

OBJECTIVE: The objective was to analyze recession of the interdental papilla in periodontally healthy situations following apical surgery using sulcular flap incisions. STUDY DESIGN: Apical surgeries were performed in 13 patients with good periodontal health. A sulcular full thickness flap involving at least 1 interproximal space was raised, using microsurgical instruments and magnification with the least possible trauma. The papillae were closed with vertical mattress sutures (polyamide 6/0) and removed after 3-5 days. The height of the interdental papilla was evaluated preoperatively and postoperatively at 1 month and 3 months using plaster casts and measured with a laser scanner. Thirteen surgical sites were compared to untreated papillae. The pairwise t test was used for statistical analysis. RESULTS: All experimental sites exhibited a significant loss of papilla height at 1 month (P <.003) and 3 months (P <.004). At 3 months retractions increased in 10 sites, while in 3 sites the loss had diminished compared to the 1-month value. CONCLUSIONS: These results suggest that the conventional sulcular flap results in considerable retraction of the papilla height after 1 month and 3 months postsurgically.     

Cigarette smoking negatively affects healing response following flap debridement surgery

BACKGROUND: The purpose of the present parallel design, controlled clinical trial was to evaluate the treatment outcome following flap debridement surgery (FDS) in cigarette smokers compared to non-smokers. METHODS: After initial therapy, 57 systemically healthy subjects with moderate to advanced periodontitis who presented with one area (at least 3 teeth) where surgery was required were selected. Twenty-eight patients (mean age: 39.6 years, 20 males) were smokers (> or = 10 cigarettes/day); 29 patients (mean age: 43.9 years, 7 males) were non-smokers. Full-mouth plaque (FMP) and bleeding on probing (BOP) scores, probing depth (PD), clinical attachment level (CAL), and recession depth (RD) were assessed immediately before and 6 months following surgery. Only sites with presurgery PD > or = 4 mm were used for statistical analysis. RESULTS: Presurgery FMP and BOP were similar in smokers and non-smokers and significantly decreased postsurgery in both groups. Overall, PD reduction and CAL gain were greater, although not significantly, in non-smokers (2.4 +/- 0.9 mm and 1.6 +/- 0.7 mm, respectively) than in smokers (1.9 +/- 0.7 mm and 1.2 +/- 0.7 mm, respectively). For moderate sites (PD 4 to 6 mm), no significant differences in PD and CAL changes were found between groups. For deep sites (PD > or = 7 mm), PD reduction was 3.0 +/- 1.0 mm in smokers and 4.0 +/- 0.8 mm in non-smokers, and CAL gain amounted to 1.8 +/- 1.1 mm in smokers and 2.8 +/- 1.0 mm in non-smokers (P = 0.0477). In smokers, 16% of deep sites healed to postsurgery PD values < or = 3 mm as compared to 47% in non-smokers (P = 0.0000); 58% of deep sites in smokers showed a CAL gain > or = 2 mm, as compared to 82% in non-smokers (P = 0.0000). CONCLUSIONS: Results of the study indicated that: 1) FDS determined a statistically significant PD reduction and CAL gain in patients with moderate to advanced periodontitis; 2) smokers exhibited a trend towards less favorable healing response following FDS compared to non-smokers, both in terms of PD reduction and CAL gain; and 3) this trend reached clinical and statistical significance at sites with initial deep PD.     

Comparison of papilla healing following sulcular full-thickness flap and papilla base flap in endodontic surgery

AIM: To compare the loss of papilla height when using the papilla base incision (PBI) or the standard papilla mobilization incision in marginal full-thickness flap in cases with no evidence of marginal periodontitis. METHODOLOGY: Twelve healthy patients referred for surgical treatment of persisting apical periodontitis, who were free from periodontal disease and had intact interdental papillae, were included in the study. The preoperative papilla height was recorded by measuring the distance between a reproducible coronal point on the tooth and the most coronal point of the papilla. The flap design consisted of two releasing incisions connected by a horizontal incision. The marginal incision involved the complete mobilization of the entire papilla in one interproximal space, and the PBI in the other interproximal space. The PBI consisted of a shallow first incision at the base of the papilla and a second incision directed to the crestal bone creating a split thickness flap in the area of the papilla base. Further, apically, a full-thickness flap was raised. In the other interproximal space, the buccal papilla was carefully incised and elevated completely. Following flap retraction, standard root-end resection and root-end filling were performed. Flap closure was achieved with microsurgical sutures. The PBI was sutured with two to three interrupted sutures (size 7/0) and the elevated papilla was reapproximated with vertical mattress sutures, which were removed 3-5 days after the surgery. The height of the interdental papilla was evaluated preoperatively and postoperatively after 1 month and at the 3-month recall, using plaster replicas. The loss of papilla height was measured using a laser scanner. Twelve papilla-paired sites were evaluated. The results were statistically analysed using the t-test. RESULTS: Complete closure of the wound was achieved in all treated sites followed by uneventful healing in all patients. The total mobilization of the papilla resulted in loss of papilla height of 1.10 +/- 0.71 mm at 1 month and 1.25 +/- 0.81 mm at the 3-month recall. At the 3-month recall, the retraction had increased in nine sites, whereas in three sites, the loss of height had slightly diminished compared to 1 month. In contrast, after the PBI, only minor changes could be detected: 0.07 +/- 0.09 mm at 1 month and 0.10 +/- 0.15 mm at 3 months. There was a significant difference between the two incision techniques studied (P < 0.007). CONCLUSIONS: In patients with healthy marginal periodontal conditions, the PBI allows rapid and predictable recession-free healing, whereas complete mobilization of the papilla led to a marked loss of the papilla height. In aesthetically relevant areas, the use of the PBI is recommended, to avoid opening of the interproximal space, when periradicular surgical treatment is necessary.     

Comparison of long-term papilla healing following sulcular full thickness flap and papilla base flap in endodontic surgery

AIM: To compare long-term loss of papilla height when using either the papilla base incision (PBI) or the standard papilla mobilization incision in marginal full thickness flap procedures in cases with no evidence of marginal periodontitis. METHODOLOGY: Twelve healthy patients, free of periodontal disease, who had intact interdental papillae were referred for surgical treatment of persisting apical periodontitis and included in the study. The flap design consisted of two releasing incisions connected by a horizontal incision. The marginal incision involved the complete mobilization of the entire papilla in one interproximal space but in the other interproximal space the PBI was performed. Further apically a full thickness flap was raised. Following flap retraction, standard apical root-end resection and root-end filling was performed. Flap closure was achieved with microsurgical sutures. The PBI was sutured with two to three interrupted sutures (size 7/0), the elevated papilla was reapproximated with vertical mattress sutures (size 7/0), which were removed 3-5 days after the surgery. The height of the interdental papilla was evaluated preoperatively and postoperatively after 1-, 3- and 12-month recall using plaster replicas. The loss of papilla height was measured using a laser scanner. Papilla paired sites were evaluated and statistically analysed. RESULTS: Most papilla recession took place within the first month after the surgery in the complete elevation of the papilla. Further small increase in loss of papilla height resulted at 3 months. After 1 year the loss of height diminished to 0.98 +/- 0.75 mm, but there was no statistical difference between the various recall intervals. In contrast, after PBI only minor changes could be detected at all times. There was a highly significant difference between the two incision techniques for all recall appointments (P < 0.001). CONCLUSIONS: In the short as well as long-term the PBI allows predictable recession-free healing of the interdental papilla. In contrast, complete mobilization of the papilla displayed a marked loss of the papilla height in the initial healing phase although this was less evident 1 year postoperatively. In aesthetically relevant areas the use of the PBI is recommended, to avoid opening of the interproximal space, when periradicular surgical treatment is necessary.     

Factors affecting the healing response of intrabony defects following guided tissue regeneration and access flap surgery

Abstract Identification and control of significant factors determining clinical outcomes is of paramount importance to improve expected results of a variety of therapeutic procedures. The aim of this investigation was to identify, with a multivariate approach, factors associated with healing outcomes of 3 penodontal surgical procedures in deep intrabony defects. 45 patients with evidence of deep intrabony defects were randomly assigned to 3 treatment groups: access flap (group C), conventional guided tissue regeneration (GTR) with non-resorbable expanded polytetrafluoroethilene (ePTFE) membranes (group B), and GTR with self supporting membranes combined with the modified papilla preservation technique (group A). In both GTR procedures, membranes were positioned coronal to the interproxymal alveolar crest. Primary outcome variables (i.e., probing attachment level gains at 1 year and the amount of newly formed tissue present at membrane removal) were explained in terms of a series of patient, defect morphology and surgical factors, using a multivariate approach. Highly significant treatment effects were observed, indicating that the 3 tested therapeutic modalities resulted in significant differences in primary outcome variables. Detailed analysis assessing the significance of the tested factors in determining the healing outcomes following each procedure was performed with a stepwise elimination approach of non-significant factors. The results indicated that: (i) the need to create and maintain space should be a key objective of regenerative approaches based upon the principles of guided tissue regeneration; (ii) control of patient's oral hygiene and residual periodontal infection in the oral cavity are strongly associated with clinical outcomes of both regenerative and conventional surgical procedures and should receive proper attention.     

Effect of citric acid and lyophilized autologous plasma on healing following periodontal flap surgery in monkeys

The purpose of this histologic, histometric, and autoradiographic study was to examine the effect of citric acid conditioning and lyophilized autologous plasma (LAP) application on healing following periodontal flap surgery. Mucoperiosteal flaps were elevated in six rhesus monkeys using the modified Widman flap procedure. A total of 24 quadrants were treated, each included the first and second premolar and first and second molar teeth. Cementum was removed from the exposed root surfaces, and reference notches were inscribed into the roots at the alveolar bone margin. Two treatment modalities were employed: (1) surgery plus citric acid conditioning, to serve as control and (2) surgery plus citric acid followed by LAP application (400 mg/ml saline). Flaps were returned to their preoperative positions and sutured. Animal sacrifices were scheduled to provide observations 3, 7, 14, 21, 28, and 45 days after surgery. Each monkey received an intravenous injection of tritiated thymidine, 1 microCi/gm of body weight, 1 hour before it was killed. Tissue specimens were processed for evaluation following standard procedures. Histologically, tissue sections were examined for: (1) proliferation and attachment of epithelium, (2) organization and maturation of periodontal fibers, (3) inflammatory cell types, (4) presence or absence of new cementum deposition, and (5) degree of vascularity of the tissues. For histometric evaluation, the radicular notches were used as reference points. The distances examined histometrically were: (1) from the root surface notch to the alveolar bone crest, (2) from the root surface notch to the apical extent of the junctional epithelium, and (3) from the free gingival margin to the apical extent of the junctional epithelium. For autoradiographic evaluation labeled cells were counted in five spatial compartments at 400 X magnification: (1) oral epithelium, (2) crevicular area, (3) supracrestal connective tissue, (4) coronal periodontal membrane, and (5) coronal bone marrow. For each the histometric and autoradiographic evaluation involved a total of 36 tissue sections per quadrant (9 sections per tooth). Tooth and quadrant means were obtained for each monkey. The plasma-treated and control quadrants were compared at each time point by the paired t test. N = 2 monkeys were used for each comparison. Histologic results showed that in teeth that were acid-conditioned after root planing, the epithelium often migrated apically reaching the radicular notch. Those teeth that were conditioned and subsequently treated with LAP demonstrated fiber attachment to the planed root surface and little or no epithelial downgrowth.(ABSTRACT TRUNCATED AT 400 WORDS)     

Bacteremia following laser and conventional surgery in hamsters

The CO2 laser prevents bleeding by sealing blood and lymph vessels as it vaporizes tissue. Bacteremia following oral surgery might not occur under these conditions. To test this hypothesis, a 0.2-mm-deep incision 1 cm long was made in the right buccal cheek pouch of hamsters using either laser, electrosurgery, or a scalpel. Twenty minutes later, 1 mL of blood was taken from each animal by cardiac puncture, inoculated on a blood agar medium, and incubated anaerobically for 4 days; then the colonies were counted. Using an operational definition of bacteremia as five colonies or more per plate, there were no positive results out of 18 trials (0/18) for laser surgery, 7/8 for electrosurgery, and 8/12 for scalpel surgery. Based on the Student t test using the binomial distribution, the laser produced statistically less bacteremia than the other two methods (P less than .01). Because the five-colony cutoff was arbitrary, the nonparametric Wilcoxon Rank test was also used. Colony formation from blood from the laser group was significantly less than from the electrosurgery group (P less than .01) and the scalpel group (P less than .05). The laser surgery group was not statistically different from the control (nonsurgerized) group. These results suggest that there is a considerable bacteremia following scalpel and electrosurgery, but that laser surgery produces no bacteremia.     

Evaluation of the healing response following placement of Coe-pak and an experimental pack after periodontal flap surgery

Abstract 2 periodontal dressings. Coe-pak* and RD8 (a product under development). were assessed following periodontal surgery, using a double-blind study of randomised split-mouth design, with each patient acting as their own control. Matched sites were selected for periodontal flap surgery under local analgesia. Sites were randomly allocated to each group. The dressings were applied by a single operator and both patients and clinical assessors were blind as to the dressing employed. The dressings were assessed as to their handling properties, m addition to a 7-day post-operative assessment of the surgical sites and a subjective patient report. Maximum pain levels were relatively low (4 in a scale 0–10); subjects reported more pain and analgesics required with RD8 than with Coe-pak, This was reflected in the results of the patient assessment which indicated that 5O% preferred Coe-pak, compared to 25%. who preferred the RD8 dressing. The results showed RD8 to be an acceptable periodontal dressing when compared to Coe-pak, There were no statistically significant differences between treated sites in both groups with regard to post-operative plaque scores, bleeding scores or tissue healing.     

Growth in width following pharyngeal flap surgery

The data reported in this investigation can be summarized in the following statements: Pharyngeal flap surgery in this sample of 17 cleft patients did not appear to produce or be related to any dramatic alterations in growth in width of the jaws or dental arches following the surgery. The only significant finding was related to an increase in basal maxillary width following flap surgery, a result opposite that described as typical of nasorespiratory obstruction. In general, the more interesting and significant relationships found between pharyngeal flap surgery and dentofacial growth in studies in the vertical and sagittal planes were not found in this evaluation of growth in width. Nasal cavity width changes with growth could not be related to the flap, but point out the possible usefulness of evaluating data such as these grouped according to cleft type.     

Changes in microvascular patterns following the periodontal flap surgery

Serial changes in the microvascular pattern beneath the inner epithelium and in the periodontal connective tissue attachment on the upper incisors in adult mongrel dogs, were studied by scanning electron microscopy to elucidate the process of reconstructing the vascular architecture following mucoperiosteal flap surgery. In the early stage of wound healing, capillaries beneath the epithelium in the marginal gingiva were transformed into glomeruli, in the course of the predominantly elongation type of angiogenesis. At the junctions, newly formed sinusoidal vessels were formed in the course of predominantly sprouting type of angiogenesis, and anastomosed with vasculatures between the flap and the periodontal membrane. In these newly formed vessels, vascular glomeruli in the marginal gingiva and newly formed sinusoidal vessels at the coronal side of the junctions were transformed into a capillary network beneath the inner epithelium accompanying the epithelization. At the apical side of the junctions, newly formed sinusoidal vessels showed a series of changes to cope with alterations of the tissue environment accompanying connective tissue attachment, but the vasculatures established after surgery showed a dense and irregular arrangement compared with the control side. These results show that the attachment mechanism obtained by wound healing differ from the original one.     

Impaired healing response of periodontal furcation defects following flap debridement surgery in smokers. A controlled clinical trial

OBJECTIVES: The purpose of the present parallel-design, controlled clinical trial was to evaluate the treatment outcome of periodontal furcation defects following flap debridement surgery (FDS) procedure in cigarette smokers compared to non-smokers. MATERIALS AND METHODS: After initial therapy, 31 systemically healthy subjects with moderate to advanced periodontitis, who presented at least one Class I or II molar furcation defect, were selected. Nineteen patients (mean age: 40.3 years, 15 males) were smokers (>or=10 cigarettes/day) and 12 patients (mean age: 44.8 years, 3 males) were non-smokers. Full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS), probing pocket depth (PPD), vertical clinical attachment level (v-CAL), and horizontal clinical attachment level (h-CAL) were assessed immediately before and 6 months following surgery. RESULTS: Overall, statistically significant v-CAL gain was observed in smokers (1.0 +/- 1.3 mm) and non-smokers (1.3+/-1.1 mm), the difference between groups being statistically significant (p=0.0003). In proximal furcation defects, v-CAL gain amounted to 2.3+/-0.7 mm in non-smokers as compared to 1.0+/-1.1 mm in smokers (p=0.0013). At 6 months postsurgery, non-smokers presented a greater h-CAL gain (1.3+/-1.1 mm) than smokers (0.6+/-1.0 mm), with a statistically significant difference between groups (p=0.0089). This trend was confirmed in both facial/lingual (1.4+/-1.0 versus 0.8+/-0.8 mm) and proximal furcation defects (1.2+/-1.3 versus 0.5+/-1.2 mm). The proportion of Class II furcations showing improvement to postsurgery Class I was 27.6% in smokers and 38.5% in non-smokers. After 6 months, 3.4% of presurgery Class I furcation defects in smokers showed complete closure, as compared to 27.8% in non-smokers. CONCLUSIONS: The results of the present study indicated that (1) FDS produced clinically and statistically significant PPD reduction, v-CAL gain, and h-CAL gain in Class I/II molar furcation defects, and (2) cigarette smokers exhibited a less favorable healing outcome following surgery in terms of both v-CAL and h-CAL gain.     

Pilot clinical studies on the effect of topical citric acid application on healing after replaced periodontal flap surgery

The effect of citric acid conditioning of the root surfaces during periodontal surgery was studied in 12 patients with residual pockets ≥ 5 mm two months following oral hygiene instruction and initial root planing. Full thickness, replaced flap procedure ("modified Widman") was performed with or without topical citric acid application using a split mouth approach. Six months post-operatively, improvement of the periodontal conditions was observed as evidenced from reduction of probing pocket depth, gain of probing attachment level and gingival recession. A mean probing attachment level gain for pooled acid treated surfaces of 2.1 mm was obtained as compared to 1.5 mm for the non-acid treated control surfaces.
Our previous dog and human studies have demonstrated new connective attachment after acid conditioning of root surfaces as contrasted to readaplation of a junctional epithelium in the non-acid treated controls. However, the results of the present study indicate that from a clinical standpoint, the use of citric acid application might only provide a small improvement in probing attachment levels.     

Effect of Tisseel on healing after periodontal flap surgery.

The purpose of this investigation was to evaluate the effect on healing of fast and slow absorbable Tisseel in combination with periodontal flap surgery. Mucoperiosteal flaps were raised on the buccal aspect of maxillary premolars and mandibular premolars and first molars in 4 beagle dogs. The underlying buccal, interproximal and inter-radicular bone was then removed to a level of approximately 5 mm apically to the original bone crest and half way into the interdental spaces and bifurcations. The exposed root surfaces were curetted in order to remove the periodontal ligament tissue, and a notch was made in the root surface at the base of the defects. On the control teeth, the flaps were sutured immediately after creation of the defects, while on the test teeth, a layer of fast (group I) or slow (group II) absorbable Tisseel was applied between the curetted roots and the subsurface of the flaps prior to suturing. Postoperatively, the teeth were brushed 2 x weekly. The dogs were sacrificed after 4 months. Histological analysis revealed that the amounts of new attachment and bone regrowth were similar in the test and control groups, although the results tended to be most favorable for the group of teeth treated with fast absorbable Tisseel (Group I).     

Microvascular response in the periodontal ligament following mucoperiosteal flap surgery

BACKGROUND: When the mucoperiosteal flap is elevated, the gingivo-periosteal vascular plexus and periodontal ligament (PDL) vascular plexus sever their connection with the circulatory tracts that pass through alveolar bone. We studied the effect exerted on the PDL vascular plexus during restoration of the circulatory tract. METHODS: We performed experimental mucoperiosteal flap surgery in adult beagle dogs. Histological specimens, prepared after injecting India ink into the blood vessels on postoperative days 5, 7, 14, 21, 28, and 42, were examined under a light microscope. In addition, vascular corrosion cast specimens of the PDL, into which acrylic resin was injected, were observed using a scanning electron microscope. RESULTS: On postoperative day 5, the PDL vascular plexus had formed new blood vessels toward the bone side and root side, and bone resorption of the alveolar bone proper had initiated primarily around the opening of the Volkmann's canal. From postoperative day 7 to 14, the PDL vascular plexus formed new vessels on the bone side and root side accompanied by bone resorption of the alveolus, and demonstrated a complicated vascular architecture, which gradually organized and transformed into a mesh structure from postoperative day 21. Osteogenesis was initiated and encircled the newly formed vessels, and the alveolar bone proper recovered to a flat morphology. Judging from the quantity of new vessels and bone resorption, the width of the PDL space seemed to be the greatest on postoperative day 14. CONCLUSIONS: When the mucoperiosteal flap was elevated, active wound healing was activated because of angiogenesis from the PDL, which possesses a microcirculatory system. Moreover, it was suggested that angiogenesis of the PDL vascular plexus and subsequent bone resorption of alveolar bone might temporarily reduce the tooth-supporting function and cause postoperative mobility.     

Low-intensity pulsed ultrasound accelerates periodontal wound healing after flap surgery

Background and Objective:  A study was conducted to evaluate the effects of low-intensity pulsed ultrasound on wound healing in periodontal tissues after mucoperiosteal flap surgery.
Material and Methods:  Bony defects were surgically produced bilaterally at the mesial roots of the mandibular fourth premolars in four beagle dogs. The flaps were repositioned to cover the defects and sutured after scaling and planing of the root surface to remove cementum. The affected area in the experimental group was exposed to low-intensity pulsed ultrasound, daily for 20 min, for a period of 4 wk from postoperative day 1 using a probe, 13 mm in diameter. On the control side, no ultrasound was emitted from the probe placed contralaterally. After the experiment, tissue samples were dissected out and fixed in 10% formalin for histological and immunohistochemical analyses.
Results:  The experimental group showed that the processes in regeneration of both cementum and mandibular bone were accelerated by low-intensity pulsed ultrasound compared with the control group. In addition, the expression level of heat shock protein 70 was higher in the gingival epithelial cells of the low-intensity pulsed ultrasound-treated tooth.
Conclusion:  Our results suggest that osteoblasts, as well as cells in periodontal ligament and gingival epithelium, respond to mechanical stress loaded by low-intensity pulsed ultrasound, and that ultrasound accelerates periodontal wound healing and bone repair.     

Alveolar bone loss in thymectomized golden hamsters.

Fifty-six neonatally thymectomized and 41 neonatally sham-operated female golden hamsters (Mesocricetus auratus) were divided into 2 groups, one inoculated with Actinomyces (N16) and the other not inoculated. All animals were raised and maintained on a high sucrose, soft diet (Diet 2000) and water, ad libitum. White blood cell counts, differentials and total lymphocyte counts were determined at 4 to 5 weeks of age. The rejection of albino hamster skin grafts and the hemagglutination response to sheep red blood cells (SRBC) were used to determine inhibition of T lymphocyte function. Evaluation of alveolar bone loss at the end of 160 days indicated that the thymectomized animals with a significant depression of the hemagglutination response to SRBC and a lack of skin graft rejections had a significantly higher bone loss than sham-operated animals. This suggests that the cellular immune response plays a role in the periodontal syndrome in hamsters. Further investigation is necessary to establish how significant this role is in relationship to the numerous other factors that are present. These data suggest that the role of the cellular immune response in the hamster periodontium may be protective rather than destructive. The role of Actinomyces (N16) in the development of bone loss was not significant.     

Alterations in crevicular fluid flow during healing following gingivectomy and flap procedures

Gingival fluid was collected from the mesial aspects of the anterior teeth of twelve patients before initial preparation and two weeks after completion of this. All pockets from which fluid was collected were measured prior to initial preparation. On twelve occasions pockets were eliminated by conventional gingivectomy and on eight flaps were reflected followed by curettage and osteoplasties. Gingival fluid was collected immediately prior to operation and at two, three and four weeks post-operatively. A strong correlation (r =+0.93: P < 0.001) was found between pocket depth and the amount of the gingival fluid exudate. Initial preparation reduced the amount of fluid flow, the extent of the reduction being significant (P < 0.01) where pockets were deep. No significant change in the amount of fluid flow had occurred two weeks after either type of operation but there were significant reductions (P < 0.01) between the third and fourth post-operative weeks when flap procedures had been performed and in the fourth post-operative week in the case of gingivectomies. The level of gingival fluid flow was the same in both groups four weeks after the operations even though it was twice as great in the flap procedures group as in the gingivectomy group before operation.     

The effect of retained subgingival calculus on healing after flap surgery

This study investigated the effects of retained subgingival calculus on healing of the periodontium at ten, 30 and 120 days. Eight beagle dogs between eight and ten years old with naturally occurring periodontal disease were used. One dog that died before any procedures were done provided information on the extent of gingival inflammation prior to surgery. Quadrants from seven dogs meeting the criteria for inclusion were selected, and each quadrant was randomly designated as either an instrumented or noninstrumented, surgical site. The gingival index for the selected sites was recorded along with clinical probing measurements. Instrumented sites were treated by reflection of a facial mucoperiosteal flap followed by thorough root planing. Non instrumented sites were treated by a facial mucoperiosteal flap alone. All flaps were returned to their preoperative position and secured with interrupted sutures. No antibiotics were given. Meticulous daily plaque control was begun the day after surgery and continued until sacrifice. There was a statistically significant reduction in gingival index scores for the 30- and 120-day instrumented sites and for the 120-day noninstrumented sites. Mean probing depths for the instrumented group showed a significant reduction at 30 and 120 days and for the noninstrumented group at 120 days after surgery. Forty percent of the noninstrumented roots and 10% of the instrumented roots displayed subgingival calculus. At all evaluation periods and in both instrumented and noninstrumented roots, inflammation was more intense when calculus was present; the difference was significant at ten days with the instrumented and at ten and 30 days with the noninstrumented specimens.(ABSTRACT TRUNCATED AT 250 WORDS)