bluuebunny/crossref_metadata_2025 huggingface dataset:
Difference in penetration of horseradish peroxidase tracer as a foreign substance into the peri‐implant or junctional epithelium of rat gingivae
Authors: Ikeda Hidehiro , Shiraiwa Masaru , Yamaza Takayoshi , Yoshinari Masao , Kido Mizuho A. , Ayukawa Yasunori , Inoue Takashi , Koyano Kiyoshi , Tanaka Teruo
Published: March 2003

Abstract: Horseradish peroxidase (HRP) tracer was applied to the gingival sulcus of implants or natural teeth at 5, 25, or 50 mg/ml to investigate the sealing capacities of the peri‐implant epithelium (PIE) and junctional epithelium (JE); the extent of HRP penetration was observed under electron microscopy. A Ti‐6Al−4V implant was inserted either immediately (immediate implantation) or 2 weeks (delayed implantation) after extraction of the maxillary left first molar of rats. The JE of the right molar was used as a control. Although the whole PIE of undecalcified sections appeared to be attached to the implant surface, electron microscopically, the internal basement lamina (IBL) and hemidesmosomes were deficient in the coronal‐middle region of the PIE. There were extensive extracellular deposits of HRP in the intercellular spaces between PIE cells, and HRP was blocked to some extent by the lamina lucida and lamina densa of the external basal lamina and basal cell junction. HRP was detected in the connective tissue under the PIE, but was not found in the connective tissue under the JE. Intracellularly, HRP was found in the vesicles and granules of PIE cells and JE cells. These were fewer in number in PIE cells than in JE cells. There were no differences between the findings for immediate and delayed implantation. The results indicate that a deficiency in the IBL permitted penetration of HRP from the gingival sulcus into the connective tissue under the PIE, and suggest that the endocytotic capacity of PIE cells is inferior to that of JE cells.
Thermal changes observed at implant sites during internal and external irrigation
Authors: Benington Ian C. , Biagioni Paul A. , Briggs James , Sheridan Sean , Lamey Philip‐John
Published: March 2003

Abstract: In the preparation of osseointegrated dental implant sites, the use of bone drilling with conventional external irrigation has been shown to be thermally non‐injurious to bovine bone, when employed as a model for dental implantology. The use of internal irrigation drilling systems is promoted on the basis of improved delivery of coolant to the bone/drill interface, which should subsequently improve local debridement and cooling, and therefore reduce thermal insults to the bone. The aim of this bovine model study was to compare the temperatures that were generated with external and internal irrigation systems during bone preparation for dental implants. A constant drill load of 1.7 kg was applied throughout the drilling procedures via a drilling rig. The burs that were used for both irrigation methods were a 2 mm twist drill for cutting the channel and a 3.25 mm drill for trephining this channel. The principal recorded parameter was the change in temperature generated via the drilling procedure. The 2 mm twist drills produced a maximum change in temperature of only 3.0°C and 3.1°C for the internal and external irrigation systems, respectively. Maximum changes for the 3.25 mm drills were 1.34°C and 1.62°C, respectively. Using the t‐test, no statistical benefit was observed for one irrigant delivery system over the other. The clinical benefit of using the more expensive internal irrigation systems is therefore deemed unjustifiable, on the grounds that these systems do not appear to reduce the thermal challenge to the bone over and above that of simple flood irrigation.
A prospective study of single stage surgery for implant supported overdentures
Authors: Fenlon Michael R. , Palmer Richard M. , Palmer Paul , Newton Jonathan T. , Sherriff Martyn
Published: March 2003

Abstract: Objectives: To investigate the clinical and psychological outcomes with ball attachment supported mandibular overdentures on Branemark implants placed in a single stage surgical approach.

Material and method: Sixteen edentulous patients aged 32–74, with atrophic (flat) mandibular residual alveolar ridges, and a history of having difficulty coping with technically adequate mandibular dentures made within the last 2 years were recruited. Mark II Branemark implants were placed using a single stage surgical technique with healing abutments placed at time of surgery. Mandibular complete dentures were modified by relieving the areas over the abutments and a resilient liner was placed. After a period of 3 months, healing abutments were replaced with ball abutments and new complete dentures were made and the patients followed for a period of 2 years. Patients completed the General Health Questionnaire (GHQ) and answered further questions relating to the functional and psychological impact of complete denture wearing before treatment and 3 months after the dentures were provided. Patients additionally completed the GHQ 2 years after overdenture insertion.

Results: Six patients suffered from loss of one of their two implants in the first 2 years after placement. Three of the implants had failed to osseointegrate, which was detected at initial loading 3 months after placement. General Health Questionnaire scores were statistically significantly reduced after treatment and the improvement was maintained over 2 years. Responses to the functional and psychological questions were similarly improved.

Conclusion: Single stage surgery led to a higher rate of implant failure than expected. Patients showed significant psychological health benefits from the treatment provided.
Bovine‐HA spongiosa blocks and immediate implant placement in sinus augmentation procedures
Authors: Artzi Zvi , Nemcovsky Carlos E. , Dayan Dan
Published: March 2003

Abstract: Bovine mineral spongiosa block (B‐SB) was used as a bone substitute in sinus augmentation procedures in 10 consecutive patients. Implants were placed during the same session. The purpose of this study was to histopathologically examine the healing of the grafted site around the implants at 12 months. Radiographic follow‐up showed apparent bone apposition in the augmented area around the implants. Clinically, all 36 implants were stable and integrated with the surrounding tissue. Histopathologically, new bone formation was evident in all specimen hard tissue cores. Hydroxyapatite particles were present in direct contact with the remodeled osseous tissue. Mallory trichrome staining showed different stages of mineralization and maturation of the newly formed bone around the grafted mineral particles. Morphometric evaluation of Picrosirius red stained slides under polarized light microscopy was performed at the peripheral/external and deep section slides of all specimens. The average bone area fraction was 34.2%, with a 1 : 5.4 mean lamellar/woven bone ratio at the peripheral side and 53.0%, with 1 : 2.5 mean ratio at the deep side. The differences of both parameters between the two sites were statistically significant. B‐SB proved to be a suitable grafting material with simultaneously placed implants in sinus floor augmentation procedures.
Dog model for study of supracrestal bone apposition around partially inserted implants
Authors: Roos‐Jansåker Ann‐Marie , Franke‐Stenport Victoria , Renvert Stefan , Albrektsson Tomas , Claffey Noel
Published: March 2003

Abstract: A dog model for study of supracrestal bone growth around partially inserted implants is described. The mandibular premolar teeth (P1, P2, P3 and P4) were extracted on both sides of the mandible in four dogs. At a surgical exposure 12 weeks later, two 10 mm titanium implants were partially inserted on each side, 15 mm apart, in the areas of the P1 and the P3 so that five threads protruded from the bone crest. A titanium mesh was fastened to the coronal aspect of the two fixtures and covered with an ePTFE membrane. Thus, a space for potential bone formation was created between the two implants. The surgical flaps were coronally positioned and secured with vertical mattress sutures. After 12 weeks of healing, biopsy specimens were retrieved and examined histologically. In three of the four dogs under study, the partially inserted implants had integrated and the intended large wound spaces had been created around the noninserted parts of the implants. However, bone was not formed around the protruding implants. Accordingly, this experimental model may prove useful for future studies on the use of various procedures that hypothetically may enhance bone formation.
Histomorphometric and fluorescence microscopic analysis of bone remodelling after installation of implants using an osteotome technique
Authors: Nkenke Emeka , Kloss Frank , Wiltfang Jörg , Schultze‐Mosgau Stefan , Radespiel‐Tröger Martin , Loos Kerstin , Neukam Friedrich Wilhelm
Published: March 2003

Abstract: The influence of the osteotome technique on the osseointegration of rough‐surfaced stepped cylinder implants (Frialit®‐2) was compared to conventional preparation of the implant site in an animal model. A total of 104 implants were placed into the distal femoral condyle of 52 New Zealand white rabbits. This region contains sufficient trabecular bone for implant placement. The implant site was prepared either by the osteotome technique or by conventional technique with drills as a control group. During the healing period polychromatic fluorescence labelling was performed with four different fluorescent dyes. After 2, 4 and 8 weeks, the implants were removed with the surrounding bone. The sample preparation was done using the ‘sawing and grinding’ technique. Ground sections 100 µm thick were used for fluorescence microscopic analysis; 30‐µm‐thick ground sections were examined histomorphometrically. After 2 weeks the bone‐to‐implant contact ratio was 55.0 ± 7.1% for the osteotome technique and 29.2 ± 4.8% for the control group (P < 0.0005). After 4 weeks, the bone‐to‐implant contact ratio was still significantly better for the osteotome technique (bone‐to‐implant contact ratio osteotome technique 71.1 ± 7.2%, bone‐to‐implant contact ratio control 59.0 ± 6.3%, P = 0.003). Eight weeks after implant placement the bone‐to‐implant contact ratio was still better for the osteotome technique compared to the conventional implant placement. However it was no longer statistically significant. The qualitative fluorescence microscopic examination showed an earlier and stronger signal for the osteotome technique than the control group. With the latter, the zone of mineralization moved slowly towards the implant surface. Implant sites prepared by the osteotome technique showed a pronounced signal in the whole compressed area already by the second day. In conclusion, the osteotome technique increases new bone formation and leads to an enhanced osseointegration of dental implants in trabecular bone. However, more experimental trials have to be carried out on higher mammals that show a metabolic rate of bone that is more comparable to humans.
The jumping distance revisited
Authors: Botticelli Daniele , Berglundh Tord , Buser Daniel , Lindhe Jan
Published: March 2003

Abstract: Following tooth extraction, a socket often presents dimensions that may be considerably greater that the diameter of a conventional implant. The present experiment was performed to study the healing that occurred adjacent to implants placed in recipient sites with a wide marginal defect. Four Labrador dogs were used. In the right side of the mandible, four experimental sites were prepared to receive titanium implants [sandblasted, large‐grit, acid‐etched (SLA) surface]. Traditional implant installation (control) was performed in one site. In the remaining three sites (test), a step drill was used to widen the marginal 5 mm of the canal. Following placement of an implant in a test site, a circumferential gap about 1–1.25 mm wide and 5 mm deep was present lateral to the implant. A resorbable barrier membrane was used to cover the implant and the bone tissue of two sites, while one site was left uncovered. Four months following implant installation, block biopsies of each implant site were obtained and prepared for ground sectioning. After 4 months of healing, the large marginal defect had been filled with newly formed bone. The degree of bone‐to‐implant contact between the newly formed tissue and the SLA surface was at all test sites high and similar to that obtained at control sites. The placement of a barrier membrane following implant installation did not improve the outcome of healing. We conclude that a marginal defect wider than 1 mm may heal with new bone and a high degree of osseointegration to an implant designed with a SLA surface.
Rat bone marrow cell response to titanium and titanium alloy with different surface roughness
Authors: Rosa Adalberto L. , Beloti Márcio M.
Published: March 2003

Abstract: In general, cell response is affected by both chemical composition and surface roughness of implant materials. The aim of this study was to evaluate the effect of titanium (Ti) chemical composition and surface roughness on the response of rat bone marrow cells, examining cell attachment, cell proliferation, total protein content, alkaline phosphatase (ALP) activity, and bone‐like nodule formation. Cells were cultured on both commercially pure titanium (cpTi) and titanium‐6‐aluminum‐4‐vanadium alloy (Ti‐A) discs with four different average roughnesses (Ra). For attachment evaluation, cells were cultured for 2 h. After 14 days, cell proliferation, total protein content, and ALP activity were evaluated. Bone‐like nodule formation was evaluated after 21 days. Data were compared by anova and Duncan's multiple range test when appropriate. Cell attachment and total protein content were affected by neither Ti chemical composition (P = 0.201, and P = 0.639, respectively) or surface roughness (P = 0.972, and P = 0.660, respectively). Proliferation, ALP activity, and bone‐like nodule formation were affected only by Ti chemical composition (P = 0.0001, P = 0.064, and P = 0.0001, respectively). These results suggest that cpTi would optimize osteoblastic differentiation by rat bone marrow cells, including reduced cell proliferation, and increased ALP activity and bone‐like nodule formation, while surface roughness, within the Ra parameters used, would not affect significantly the rat bone marrow cell response.
Temperature changes induced by 809‐nm GaAlAs laser at the implant–bone interface during simulated surface decontamination
Authors: Kreisler Matthias , Al Haj Haitham , D'Hoedt Bernd
Published: March 2003

Abstract: The aim of the study was to investigate temperature changes at the implant–bone interface during simulated implant surface decontamination with a 809‐nm gallium‐aluminium‐arsenid (GaAlAs) semiconductor laser. Stepped cylinder implants with a diameter of 3.8 mm and a length of 11 mm with two different surfaces (sand‐blasted and acid etched, and hydroxyapatite‐coated) were inserted into bone blocks cut from freshly resected pig femurs. Access holes of 0.5 mm were drilled into the bone, to allow K‐type thermocouples to contact periimplant bone in different parts of the cavity. An artificial periimplant bone defect provided access for laser irradiation in the coronal third. A 600‐μm optic fiber was used at a distance of 0.5 mm from the implant surface. Power output varied between 0.5 and 2.5 W in the continuous wave mode. The bone block was placed into a 37°C water bath in order to simulate in vivo thermal conductivity and diffusitivity of heat. Temperature elevations during irradiation were registered for a period of 120 s. In mean, the critical threshold of 47°C was exceeded after 9.0 s at 2.5 W, 12.5 s at 2.0 W, 18.0 s at 1.5 W and 30.5 s at 1.0 W. Surface characteristics did not have a significant effect on temperature elevations. In an energy‐dependent manner, implant surface decontamination with an 809‐nm GaAlAs laser must be limited in time to allow the implant and bone to cool down. Clinical guidelines are presented to avoid tissue damage.
Effect of an essential oilcontaining antiseptic mouthrinse on plaque and salivary Streptococcus mutans levels
Authors: Fine D. H. , Furgang D. , Barnett M. L. , Drew C. , Steinberg L. , Charles C. H. , Vincent J. W.
Published: March 2003

Background: Clinical studies in which antimicrobial mouthrinses were shown to have significant antiplaque activity most frequently have used gingivitis as the clinically relevant endpoint. However, there is evidence to suggest that mouthrinses containing active agents effective against Streptococcus mutans, such as chlorhexidine, may also have a rôle in inhibiting dental caries. This clinical study was conducted to determine the effect of 2×‐daily rinsing with an essential oilcontaining antiseptic mouthrinse (Listerine® Antiseptic) on levels of recoverable S. mutans and total streptococci in supragingival interproximal plaque and in saliva. Additionally, a follow‐up in vitro study is reported which determined whether a differential susceptibility to the antiseptic mouthrinse exists among different strains of streptococci.

Method: Following baseline saliva and plaque sampling for quantification of recoverable S. mutans and total streptococci, 29 qualifying subjects were randomly assigned either the essential oil mouthrinse or a sterile water control. They rinsed with 20 ml for 30 s 2×daily for 11 days and once on the 12th day, in addition to their usual oral hygiene procedures. On day 12, saliva and plaque samples were again collected and microbiological quantification performed. The procedures were repeated with the alternate rinse after a 1‐week washout period.

Results: The essential oil mouthrinse produced respective reductions of 69.9% and 75.4% in total recoverable streptococci and in S. mutans in plaque, and corresponding reductions of 50.8% and 39.2% in saliva. The in vitro study revealed that streptococci from the mutans group were more susceptible to the bactericidal activity of the essential oil mouthrinse than streptococci from the mitis group.

Conclusions: As antimicrobial mouthrinses are most frequently recommended to patients whose mechanical oral hygiene procedures are not adequate for the control of supragingival plaque and gingivitis, this study provides an additional rationale for the inclusion of the essential‐oil mouthrinse as an adjunct to daily oral hygiene procedures.
Periodontal flap surgery with 25% metronidazole gel
Authors: Needleman Ian G. , Collins Angela M. , Moles David R.
Published: March 2003

Objectives:

The aim of this 12‐month, randomised controlled, single‐blind, parallel‐arm study, was to test whether local application of a slow‐release antimicrobial might exert an adjunctive effect on healing following periodontal surgery.

Materials and Methods:

Following non‐surgical therapy, 43 patients with moderate to advanced periodontitis, had at least 1 pocket 6 mm with bleeding on probing (BOP). Treatment consisted of modified Widman surgery with no osseous resection. The test group (T) received gel application over the exposed root surface and the control group (C) received no gel, followed by flap closure.

Results: 38 patients completed the study: 5 patients did not attend at 12 months and could not be traced. Surgery was very successful in both groups in improving probing depths (mean baseline: T=7.4 mm, C=7.1 mm; 12 months T=3.7 mm, C=3.5 mm) and relative attachment levels (baseline: T=10.3 mm, C=10.1 mm; 12 months T=8.2 mm, C=8.8 mm). Differences between groups were not significant at 12 months, although the improvements within groups between baseline and 12 months were highly statistically significant (p<0.01). Plaque and BOP levels were low in both groups after treatment.

Conclusion: MWF surgery was effective in establishing the periodontal health of sites with advanced disease and this study was unable to detect an additional benefit to using a 25% metronidazole gel.
Periodontal healing after intentional auto‐alloplastic reimplantation of injured immature upper front teeth
Authors: Pohl Yango , Filippi Andreas , Tekin Ugur , Kirschner Horst
Published: March 2003

Background/aims:

Conventional endodontic treatment results in high complication quota when performed in immature teeth. Intentional reimplantation with extraoral insertion of an endodontic implant (auto‐alloplastic reimplantation) is an alternative.

Method: In a retrospective study, the healing of 40 teeth reimplanted intentionally according to this method in patients aged 7 to 15 years was evaluated. Clinical tests (palpation, percussion sound, periotest values) and radiographical examinations were used to determine the type of periodontal healing (inflammatory resorption/periodontitis apicalis; replacement resorption/ankylosis; normal healing).

Results: Mean lifetime of the replanted teeth was 59.2±42.5 months, estimated survival time on the basis of the Kaplan‐Meier analysis was 99.5 months. 17 teeth (42.5%) were classified as failures, mostly due to inflammatory resorption or periodontitis apicalis. Further investigations demonstrated that success rate and retention period of intentionally replanted teeth depend on the preoperative condition of the pulp. Teeth with preoperative infection suffered frequently from inflammatory resorption or periodontitis apicalis after being replanted (14 of 28 teeth). Estimated survival time according to Kaplan‐Meier was 75.5 months. In contrast, inflammations or progressive resorptions were not observed in teeth without preoperative infection of the pulp. All these 12 teeth showed normal periodontal healing and regular tooth mobility. In the absence of any pathology in clinical or radiological findings after an average functional period of 72.3 months, the prognosis can be presumed excellent. Estimated survival time of 148.3 months according to Kaplan‐Meier differs significantly from survival time of teeth infected preoperatively.

Conclusions: From the results of this investigation, it may be concluded that an infection of the pulp – due to delay of treatment or attempts at endodontic therapy – should be avoided before intentional replantation of immature front teeth with pulp necrosis. Periodontal healing of the autologous root is not impaired by the insertion of posts made of Al2O3‐ceramics or titanium. The inserted posts do not ankylose. Orthodontic movement of auto‐alloplastically replanted teeth is possible.
Determination of the in situ bactericidal activity of an essential oil mouthrinse using a vital stain method
Authors: Pan P. , Barnett M. L. , Coelho J. , Brogdon C. , Finnegan M. B.
Published: March 2003

Background: Recent research has indicated that bacteria within a biofilm may undergo changes in susceptibility to antimicrobial agents when compared to planktonic forms. This study was conducted to determine the bactericidal effect of an essential oil‐containing mouthrinse (Listerine® Antiseptic) on dental plaque bacteria in situ.

Methods: 1‐day‐old plaque in 17 subjects was sampled at baseline from the buccal surfaces of diagonally contralateral maxillary and mandibular bicuspids and 1st molars. Subjects were then randomly assigned either an essential oil mouthrinse or a sterile saline negative control and rinsed under supervision with 20 ml for 30 s. 30 min later, plaque was sampled from the remaining contralateral posterior teeth. Subjects repeated these procedures with their respective alternate rinse after 1 week. Pooled plaque samples from each subject at each sampling period were stained with a commercially‐available fluorescent stain which fluoresces live and dead bacteria green and red, respectively. The stained plaque specimens were analyzed using computerized image analysis. A separate in vitro study was conducted to determine the relationship between the % red stain per sample and bacterial viability.

Results: Analysis of vital stained plaque specimens indicated that following rinsing with the essential oil mouthrinse, 78.7% of bacteria were dead compared to 27.9% following rinsing with the negative control (p<0.001). The in vitro findings demonstrated that the % red stain per sample is reflective of actual bacterial kill.

Conclusions: This study confirms the findings of previous in vitro and in vivo studies which demonstrated the essential oil mouthrinse to have significant biocidal activity against oral micro‐organisms. These studies all support the primacy of a bactericidal mechanism in producing the plaque and gingivitis reductions observed in numerous clinical trials conducted on the essential oil mouthrinse.
A laboratory and clinical investigation comparing 2 oscillating/rotating electric toothbrushes
Authors: Danser M. M. , Driesen G. M. , Timmerman M. F. , Van Der Velden U. , Van Der Weijden G. A.
Published: March 2003

Background/aims: The purpose of the study was to investigate the efficacy of plaque removal by 2 different toothbrushes in a laboratory model and in a clinical study.

Method: The 2 brushes used were the Philips/Jordan HP 735® and the Braun Oral‐B Ultra Plaque Remover® (D9). Both were compared in a laboratory study (using a robot system) and a short‐term clinical study. For the laboratory study, plaque substitute was applied to the artificial teeth of ten typodonts, which were cleaned by a robot for 2 min. The remaining plaque substitute was measured on buccal and lingual/palatal surfaces, as well as gumline and interproximal sites, using a computerized vision system. The clinical study included 23 non‐dental students. All subjects received a single oral prophylaxis and were asked not to brush their teeth for 48 h prior to their appointment. After the amount of plaque had been evaluated at 6 sites per tooth, subjects brushed in a random split‐mouth order with the 2 electric toothbrushes, after which the amount of plaque was re‐evaluated.

Results: The results of the laboratory study showed that, for all surfaces combined, the mean removal of plaque substitute for both brushes was the same. However, at the vestibular and the approximal vestibular surfaces, the reduction in plaque substitute was significantly higher (p<0.01) with the Braun toothbrush compared to the Philips. In the clinical study, the mean overall plaque reduction for the Braun toothbrush (74%) was significantly higher than for the Philips (66%). Further analysis revealed that the significant difference in favour of the Braun brush was mainly due to plaque removal from the approximal vestibular and the approximal lingual sites.

Conclusions: In conclusion, both the laboratory and clinical study show that the Braun Oral‐B Ultra Plaque Remover® (D9) is more effective than the Philips/Jordan HP 735®. Both study models indicate that this difference is greatest on the approximal vestibular surfaces.
Serum IgG reactivity to subgingival bacteria in initial periodontitis, gingivitis and healthy subjects
Authors: Tanner A. C. R. , Kent R. L. , Maiden M. F. J. , Macuch P. J. , Taubman M. A.
Published: March 2003

Background/aims: Established periodontal diseases may be associated with antibody responses to periodontal pathogens, but it is not known at which stage of disease this antibody response is initiated. This study aimed to characterize the host systemic response in initial periodontitis, gingivitis, and periodontal health, to evaluate whether elevated serum antibodies to subgingival species could be detected in initial periodontitis.

Method: Human systemic immune response were evaluated to 40 subgingival bacterial species in 16 healthy, 21 gingivitis, 11 initial periodontitis and 5 progressing recession adults. Subjects had minimal periodontal attachment level (AL) loss at baseline. Disease categories were determined after 12 months monitoring at three‐month intervals. Increased AL loss 1.5 mm (disease activity) at interproximal sites defined initial periodontitis, recession was characterized by AL loss at buccal sites. Serum IgG antibodies were evaluated semi‐quantitatively by immunoblot from blood taken at baseline, active and final visits.

Results: No antibody was detected from 55% of reactions. When detected, levels were below those reported for advanced periodontitis subjects. There were no major differences in serum antibody levels between healthy, gingivitis and initial periodontitis subjects, despite differences in the subgingival microbiota. Serum antibodies for more species were detected in recession subjects, compared with the other study subjects. No changes in antibody levels were detected between baseline, active, and final visits. No systematic association between species colonization and presence of systemic antibody was observed.

Conclusions: This study did not detect differential elevation of mean serum antibody levels in initial periodontitis subjects, suggesting that serum antibody levels are not sensitive risk markers for initial periodontitis.
Prevalence of Actinobacillus actinomycetemcomitans and clinical conditions in children and adolescents from rural and urban areas of central Italy
Authors: Paolantonio Michele , Di Bonaventura Gianni , Di Placido Giacinto , Tumini Vincenzo , Catamo Giovanni , Di Donato Angelo , Piccolomini Raffaele
Published: March 2003

Background: The aim of this study was to report on the prevalence of Actinobacillus actinomycetemcomitans (Aa) and the periodontal clinical conditions in children and adolescents from a rural area of central Italy compared with the ones from an urban area of the same region.

Method: The study population consisted of 780 systemically healthy children, aged 6–14 years inhabiting the county of Chieti. 505 children attended 3 primary and 2 secondary schools from a rural area whereas 275 individuals attended 1 primary and 1 secondary school from the city of Chieti. The 2 provincial areas present a great difference in socioeconomic level and cultural background. Clinical examination consisted of recording the % of gingival sites positive for the presence of plaque (Pl+), bleeding on probing (BOP+), mean probing depth (PD) from each primary or permanent tooth fully erupted in the oral cavity. Loss of periodontal attachment (AL+) was evaluated only in interproximal sites. AL+ subjects were distinguished in juvenile periodontitis (JP) prepubertal periodontis and early periodontitis (EP) patients. 8 gingival sites were microbiologically sampled in each subject and cultured, after pooling, for the presence of Aa.

Results: 30.3% of rural subjects, were positive for the presence of Aa, the difference from urban children (16%) being statistically significant (p=0.01) irrespective of gender and age. Aa showed a significantly (p=0.006) higher mean proportion in subgingival plaque samples from rural children (0.13% versus 0.02%). Loss of periodontal attachment in at least one site was found in 18 rural children (3.56%) (3 JP; 15 EP) and 2 urban girls (0.72%) (1 JP; 1 EP). No significant differences for AL were observed within the rural group according to the gender and age differentiation. In the urban group, both AL+ subjects were Aa+, while among children from rural areas all 3 JP and 13 EP subjects were Aa+. Rural subjects evidenced significantly worse clinical parameters with respect to urban children (% Pl+ sites: p=0.000; % BOP+ sites: p=0.010; mean PD: p=0.000.) The relative risk for AL+ sites was significantly greater (2.42) in rural subjects harboring Aa in subgingival plaque. Similarly, the presence of Aa in subgingival plaque was related to a greater risk of more than 50% of BOP+ gingival sites in both rural and urban subjects (1.45 and 8.40, respectively).

Conclusions: Results of this study suggest that Aa colonization in children and adolescents from central Italy is affected by socioeconomic and cultural factors; these factors also affect the periodontal condition of the subjects.
Pharmacodynamic effects of ketoprofen on crevicular fluid prostanoids in adult periodontitis
Authors: Paquette D. W. , Lawrence H. P. , McCombs G. B. , Wilder R. , Binder T. A. , Troullos E. , Annett M. , Friedman M. , Smith P. C. , Offenbacher S.
Published: March 2003

The reported therapeutic benefits of nonsteroidal anti‐inflammatory drugs (NSAIDs) in slowing periodontal disease progression appear intimately linked to the effective inhibition of local prostaglandin synthesis. This randomized, partially double‐blind, controlled trial was conducted to evaluate the pharmacodynamic effects of the NSAID, ketoprofen (KTP), on gingival crevicular fluid (GCF) prostanoids. 42 subjects, ages 35–57 years, with moderate to advanced adult periodontitis were recruited and monitored for 22 days. On day 1, subjects were randomized for 1 of 5 treatments: i) 0.5% KTP gel; ii) 1.0% KTP gel; iii) 1.0% KTP alternate gel; iv) 2.0% KTP gel; v) 25 mg KTP capsule (positive control). Subjects applied 1 ml of gel topically to their gingiva or administered one capsule p.o., b.i.d. for 14.5 days. GCF samples were collected from posterior, interproximal sites on days 1 (pre‐dosing; 1, 2, 3, 6 h), 8 (pre‐dosing; 2 h), 15 (pre‐dosing; 2 h) and 22 (post‐treatment). GCF levels of prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) were determined using RIA, and expressed in ng/ml and % reduction from baseline (%Effect). Neither a significant difference among groups nor a dose response in % effect for either prostanoid was evident, both overall and among cohorts with elevated baseline mediator levels ([PGE2]>34 ng/ml; [LTB4]>300 ng/ml). When data were combined from all groups, significant (p<0.01) % reductions in GCF PGE2 were noted at 1 and 2 h post‐dosing (29% and 24%, respectively). In comparing topical versus systemic formulations, all topical formulations were as equipotent as systemic dosing in altering local prostaglandin levels despite lower KTP exposures with gel treatments. These data indicate that both topical and systemic KTP therapies pharmacodynamically reduce GCF PGE2 levels in adult periodontitis subjects, allowing for potential inhibition of disease progression.
Effect of subgingival scaling during supportive therapy
Authors: Jenkins William M. M. , Said Samsiah H. M. , Radvar Mehrdad , Kinane Denis F.
Published: March 2003

Background, aims: This prospective study was designed to investigate the rôle of root débridement at 3 month intervals for patients with periodontitis whose disease had persisted following the completion of conventional periodontal treatment.

Methods: 39 maintenance patients with at least 4 pockets at least 4 mm deep were assigned to coronal scaling (CS) and subgingival scaling (SS) groups. Probing depths (PD), bleeding on probing (BOP) and relative attachment levels (RAL) were recorded at all eligible sites at baseline and 3, 6, 9 and 12 months later. Plaque index scores were recorded at the 12‐month visit. At every visit, following data collection, both groups received a coronal scaling and the SS group, in addition, received a thorough subgingival débridement. In the CS group, subgingival débridement was performed only for ‘loser’ sites which enhibited loss of attachment 2 mm relative to baseline values. Due to low compliance, only 31 patients completed the study. Thus, data analyses were carried out for 130 sites in 17 CS group patients and 146 sites in 14 SS group patients.

Results: During the course of the study, 21 loser sites were identified in each group, but the difference in proportion of loser sites between groups was not significant. Furthermore, although there was a trend toward PD reduction in both groups throughout the study, mean PD, RAL and BOP values were not significantly different from baseline values at any time point, and there were no significant differences between groups with respect to these variables. Mean plaque scores measured at the 12‐month visit revealed no significant differences between groups.

Conclusion: These findings call into question the value of performing repeated subgingival scaling at 3‐month intervals for patients with persistent disease.
Association of interleukin‐1 gene polymorphisms with early‐onset periodontitis
Authors: Parkhill Judith M. , Hennig Branwen J. W. , Chapple Iain L. C. , Heasman Peter A. , Taylor John J.
Published: March 2003

Background, aims: Early onset periodontal diseases (EOP) are a group of inflammatory disorders characterised by a rapid rate of periodontal tissue destruction, in young individuals who are otherwise healthy. There is now substantial evidence to suggest that genetic factors play a rôle in the pathogenesis of EOP but the precise nature of these factors remains unclear. Polymorphisms in cytokine genes which may underpin inter‐individual differences in cytokine synthesis and secretion have been associated with other diseases which have an inflammatory pathogenesis, including chronic adult periodontal disease (CAPD).

Method: We therefore investigated the frequency of polymorphisms in the genes encoding interleukin‐1β (IL‐1β) and its receptor antagonist (IL‐1RA) in 70 EOP patients, including a subgroup of 21 localised EOP (L‐EOP) patients and 72 periodontally healthy controls. All subjects were of Caucasian heritage and systemically healthy. A single nucleotide polymorphism (SNP) in exon 5 of the IL‐1β gene (IL‐1β+3953) was analysed by amplifying the polymorphic region using PCR, followed by restriction digestion with Taq1 and gel electrophoresis.

Results: The frequency of IL‐1β genotypes homozygous for allele 1 (corresponding to the presence of a restriction site) of the IL‐1β+3953 SNP was found to be significantly increased in EOP patients (χ2 test, p=0.025). Upon stratification for smoking status a significant difference was found in the IL‐1β genotype distribution between EOP smokers compared to control smokers (F‐exact test, p=0.02), but not between EOP non‐smokers and control non‐smokers. The IL‐1β 1/1 genotype occurred at a higher frequency in EOP smokers (odds ratio=4.9) compared to control smokers. A variable number tandem repeat polymorphism (VNTR) in intron 2 of the IL‐1RA gene was analysed by amplifying the polymorphic region using PCR and fragment size analysis by gel electrophoresis. There was no evidence for an association of an IL‐1RA genotype with EOP. However the combination of IL‐1β allele 1 and IL‐1RA allele 1 (corresponding to 4 repeats) was associated with EOP (Clump, p=0.01).

Conclusions: These findings suggest that an IL‐1β genotype in combination with smoking, and a combined IL‐1β and IL‐1RA genotype are risk factors for EOP and support a role for genetic and environmental factors in susceptibility to EOP.
Bacterial susceptibility to amoxicillin and potassium clavulanate in advanced periodontitis patients not responding to mechanical therapy
Authors: Kleinfelder J. W. , Müller R. F. , Lange D. E.
Published: March 2003

Background, aims: Between 4 and 8% of periodontitis patients are reported to respond poorly to conventional therapy. In these cases, adjunctive use of systemic antibiotics might be a reasonable therapeutic approach. The purpose of this study was to evaluate the effects of systemic amoxicillin/clavulanate as adjunct to periodontal surgery on the predominant subgingival microorganisms in patients not responding to mechanical therapy. Furthermore, the bacterial susceptibility to amoxicillin/clavulanate was analyzed before and after therapy in order to assess the clinical validity of pre‐therapeutic susceptibility testing.

Methods: In 10 periodontitis subjects with no subgingival detection of Actinobacillus actinomycetemcomitans, the predominant subgingival organisms were identified using the identification system Rapid ID 32 A as well as antibiotic susceptibility was tested utilizing the E test.

Results: Porphyromonas gingivalis and Prevotella oralis were detected in 7/10 subjects and could no more recovered after therapy. Fusobacterium nucleatum and Peptostreptococcus micros were present in 5/10 patients before treatment, but could be detected in 6/10, resp. 3/10 after therapy. In 4/10 subjects harboring F. nucleatum and in 3/10 with P. micros, those organisms were not targeted by amoxicillin/clavulanate, although post‐treatment testing revealed their alleged susceptibility (MICs varied from 0.023 to 0.032 μg/ml, resp. from 0.125 to 2.0 μg/ml).

Conclusions: The results of this study suggest that the outcomes of conventional methods of susceptibility testing have to be interpreted very carefully when being used for treatment of plaque‐related diseases. Furthermore, since the endpoint of systemic antibiotic treatment as adjunct to conventional therapy is elimination of F. nucleatum or P. micros in patients harboring these organisms, the use of amoxicillin/clavulanate appears not to be justified.
Comparison of a conventional and modified tooth stain index
Authors: Macpherson L. M. D. , Stephen K. W. , Joiner A. , Schäfer F. , Huntington E.
Published: March 2003

Objectives:

To evaluate a modified tooth stain index and determine the effect of dietary factors on stain formation.

Methods: At baseline, 182 adult volunteers were given a full oral prophylaxis followed by stain assessment using a modification of the Lobene index. This involved assigning separate scores to the mesial (M) and distal (D) sites of each tooth, in addition to the standard gingival area (G) and tooth body (B). For each site, stain intensity and areas were scored. The sum of (intensity×area) scores was calculated for all sites (GBMD‐value) and for the gingival and body sites only (GB‐value). The subjects used a standard abrasive dentifrice and a soft toothbrush for 6 weeks.

Results: Stain was reassessed and the average increase in GBMD‐value was 20.9 (sd=9.9) (buccal aspect) and 29.9 (sd=18.0) (lingual aspect). The corresponding GB‐values were 4.4 (sd=4.8) and 12.5 (sd=10.2). The coefficients of variation of the GBMD index values were consistently lower than those of the GB values. Smoking and tea‐drinking were found to be the only significant (p<0.001) factors investigated for stain formation.

Conclusions: It is concluded that the modified index may well be advantageous to its conventional counterpart because sites with most visible stain are assessed separately and because it may also offer higher discriminatory power due to a lower coefficient of variation.
Comparison of clinical outcomes following treatment of chronic adult periodontitis with subgingival scaling or subgingival scaling plus metronidazole gel
Authors: Griffiths G. S. , Smart G. J. , Bulman J. S. , Weiss G. , Shrowder J. , Newman H. N.
Published: March 2003

Background, aims: Conventional treatment of chronic periodontitis involves mechanical debridement of periodontal pockets. Recently, subgingival antimicrobials have been used adjunctively following such debridement. This 2‐centre study compared the clinical effects of subgingival scaling (SRP) with SRP plus subgingival application of 25% metronidazole gel, Elyzol® (SRP+gel), in patients with chronic adult periodontitis.

Method: Voluntary informed written consent was obtained from 45 subjects at the Eastman (mean age 46, range 34–63) and 43 subjects at RAF Halton (mean age 47, range 34–71) who participated in this blind, randomised split‐mouth design study. All had at least 2 sites in each quadrant with probing pocket depth (PPD) 5 mm. PPD, bleeding on probing (BOP), and clinical probing attachment levels (CAL) measured using a stent, were recorded at baseline and at 1, 3, 6 and 9 months post‐therapy. After subgingival scaling of all quadrants, 2 quadrants were randomly selected to be treated with metronidazole gel.

Results: A paired t‐test on baseline values showed no bias between groups. Both treatments effectively reduced the signs of periodontitis. At each follow‐up visit, reduction in PPD, CAL and BOP after the combined treatment was greater than for SRP alone. Paired t‐tests showed that the improvement in the SRP+gel group was statistically significantly better (p<0.001) than for SRP alone (mean 0.5±0.6 mm. 95% CI 0.4–0.6 mm.) Similarly, the % of sites which improved to a final pocket depth of 3 mm and the % of sites which improved over the 9 months of the study by as much as ≥2 mm were greater for SRP+gel than for SRP alone.

Conclusions: At the end of the study, the mean reductions for PPD were 1.0 mm (SRP) compared to 1.5 mm (SRP+gel), and for CAL they were 0.4 mm (SRP) compared to 0.8 mm (SRP+gel), with mean difference for CAL between treatments of 0.4±0.6 mm (95% confidence intervals of 0.3–0.6 mm). The combination therapy of SRP+gel was superior to the conventional treatment of SRP alone, and these differences were maintained for 9 months.
Osseointegrated implants in a patient with Papillon‐Lefèvre syndrome
Authors: Ullbro Christer , Crossner Claes‐Göran , Lundgren Tord , Stålblad Per‐Åke , Renvert Stefan
Published: March 2003

Background: The Saudi female reported in this study was diagnosed with Papillon‐Lefèvre syndrome. She had lost all her teeth, including third molars, at the age of 18 years.

Method: She was wearing full dentures for 7 years, before 5 titanium implants were installed in the mandible.

Results: 4½ years after the implant installation, the treatment was clinically and radiographically successful. Neither A. actinomycetemcomitans nor P. gingivalis were detected at any of the implants. This very encouraging result does not differ from what is generally reported in edentulous medically healthy patients.

Conclusion: The use of implants could considerably enhance future therapeutic options for the severely dentally compromised patients with Papillon‐Lefèvre syndrome.
Effect of non‐surgical periodontal treatment on clinical parameters and the numbers of Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans at adult periodontitis sites
Authors: Doungudomdacha S. , Rawlinson A. , Walsh T. F. , Douglas C. W. I.
Published: March 2003

Background, aims: The purpose of this study was to relate the numbers of Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans cells to clinical parameters at diseased and healthy periodontal sites before and after non‐surgical periodontal therapy using a sensitive quantitative PCR method (Q‐PCR).

Method: The sensitivity of the Q‐PCR was less than 10 cells for all three species. Subgingival plaque samples were collected from 541 sites in 50 adult periodontitis subjects pre‐treatment, post‐treatment and at a follow‐up visit (3–6 months post‐treatment). Pocket probing depth, attachment loss and bleeding on probing were recorded at each visit and both healthy and diseased sites in each subject were sampled.

Results: Quantification revealed that P. gingivalis counts were associated with pocket depth (p=0.006) and attachment loss (p=0.010); however, neither P. intermedia nor A. actinomycetemcomitans was associated with the clinical signs examined. Post‐treatment, there was a significant decrease in the numbers of all three species in both the diseased and healthy sites (86–99%) but none were eradicated. Positive associations were found between any two of the three species studied both pre‐ and post‐therapy. By the follow‐up visit, there was a significant improvement in the probing depth of deep sites (p=0.001) but in no other clinical parameters.

Conclusion: This study demonstrates the usefulness of Q‐PCR for enumerating putative pathogens in clinical periodontal specimens and that the numbers of the three organisms in all sites decrease with non‐surgical periodontal therapy.
Chlorhexidine varnishes: a review
Authors: Matthijs S. , Adriaens P. A.
Published: March 2003

Background: Of all chemical plaque control agents, chlorhexidine digluconate has proven to be the most effective and safe. Since 1964, varnishes have been used for local delivery of fluor and are reported to be an effective and easy to use vehicle. During the past decade, varnishes for local delivery of antimicrobial agents have been developed and investigated in vitro and in vivo.

Aim: In this paper, the existing literature on the use of 3 different chlorhexidine varnishes in different fields in dentistry is reviewed.

Method: In vitro results concerning the release of the antimicrobial agents are compared for the 3 different varnish formulations.

Results and conclusion: Clinical reports on the efficacy of controlled‐release systems in altering cariogenic and periodontopathic microflora are summerized.