bluuebunny/crossref_metadata_2025 huggingface dataset:
Freestanding and tooth‐implant connected prostheses in the treatment of partially edentulous patients
Authors: Naert Ignace E. , Duyck Joke A. J. , Hosny Mahmoud M. F. , Van Steenberghe Daniël
Published: March 2003

Abstract: In 123 patients, 339 implants were connected to 313 teeth by means of fixed partial prostheses (test) and followed up for 1.5–15 years (mean: 6.5). In another ad random selected 123 patients, 329 implants were connected to each other by means of 123 freestanding fixed partial prostheses (control) and were followed up for 1.3–14.5 years (mean: 6.2). The aim of this study was to compare both treatment modalities with each other based on implant, tooth and prosthesis complications. The cumulative implant success, based on implant immobility and/or lack of implant fractures after loading, in the test and control groups amounted to 95% and 98.5%, respectively. Although in the test group 10 implants versus only 1 in the control group failed, a regression analysis of the survival data, based on the cox proportional hazards model, revealed no significant difference. In the test group periapical lesions (3.5%), tooth fracture (0.6%) and tooth extraction due to fatal decay or periodontitis (1%) were observed, besides tooth intrusion (3.4%) and crown cement failure (8%). Framework fracture occurred in 3 patients. In the control group, only 2 abutment screws fractured. The treatment of partial edentulism by means of oral implants was beneficial for our patients. Because of a clear tendency of more implant failures (mobility or fractures) and tooth complications in the tooth‐implant connected prostheses, the freestanding solution is the primary option to be considered. To avoid intrusion of abutment teeth, the connection, if made, should be completely rigid.
A meta‐analytic, quantitative assessment of osseointegration establishment and evolution of submerged and non‐submerged endosseous titanium oral implants
Authors: Boioli L. T. , Penaud J. , Miller N.
Published: March 2003

Abstract: Two implant placement methods are used in oral implantology: submerged (S, two‐stage surgical procedure) and non‐submerged (NS, one‐stage surgery). However, a quantitative assessment of their influence on implant osseointegration, summarising the whole present experience, is not directly possible, owing to the lack of normalisation of the published results. To overcome this difficulty, selection criteria have been applied to the latter in a process of a meta‐analysis of specialised literature, in order to authorise a pooled treatment with an adequate statistical method. Survival life tables are established (up to 15 and 10 years respectively for S and NS implants placed in normal situations) for extended samples (13049 S and 5515 NS implants). Early (before loading) failure rates and 95% confidence level ranges of cumulative implant survival rates are shown. For both categories, the quality of the placement stage remains critical to ensure optimal osseointegration behaviour. Both categories match current survival requirements, but with a quite different behaviour over time. NS implants, while osseointegrating better initially, are subject to causes of osseointegration loss, which persist over a longer period of time. Implant design characteristics (including the type of surface) seem to be more relevant than the placement procedure for the implant’s behaviour. This is in agreement with recent histological and preliminary clinical results, and should be confirmed by further studies.
Morbidity of harvesting of retromolar bone grafts: a prospective study
Authors: Nkenke Emeka , Radespiel‐Tröger Martin , Wiltfang Jörg , Schultze‐Mosgau Stefan , Winkler Gerhard , Neukam Friedrich Wilhelm
Published: March 2003

Abstract: 20 retromolar bone grafts were harvested in outpatients for augmentation of the implant site from January to June 2000 (10 female, 10 male, 40.9 ± 12.8 years, minimum 17 years, maximum 66 years). The aim of the study was to assess typical complications of this procedure in a prospective manner. For the determination of the superficial sensory function of the inferior alveolar and the lingual nerve, an objective method was used. The bone grafts were harvested for single tooth reconstruction. In 14 cases a ridge augmentation and in 6 cases an endoscopically controlled crestal sinus floor elevation was performed. Preoperatively, the height of bone above the cranial aspect of the inferior alveolar nerve in the retromolar region was assessed radiologically with known markers. The maximum mouth opening was determined. The superficial sensory function of the inferior alveolar and the lingual nerve was assessed with the Pointed‐Blunt Test, the Two‐Point‐Discrimination Test and the objective method of the ‘Pain and Thermal Sensitivity’ Test (PATH Test). Moreover, the pulp sensitivity of the teeth of the donor site was determined by cold vitality testing. All tests were repeated 1 week postoperatively. Intraoperatively, the width of the retromolar region was measured with a caliper. The patients rated the operative strain on a visual analogue scale. The height of bone above the inferior alveolar nerve in the retromolar region was 11.0 ± 2.2 mm. The width of the retromolar area was 14.2 ± 1.9 mm. Postoperatively, the maximal mouth opening changed significantly (40.8 ± 3.5 mm preoperatively, 38.9 ± 3.7 mm postoperatively, P = 0.006). However, the reduction was not relevant clinically. A direct injury of the inferior alveolar or lingual nerve did not occur. A sensitivity impairment could not be detected for either of the nerves by the different test methods 1 week postoperatively. The operative strain related to the donor site was significantly less than the strain generated by the implant placement (rating on a visual analogue scale 2.8 ± 1.0 and 4.1 ± 2.0, respectively, P = 0.027). Retromolar bone grafts are a viable method for augmentation of the implant site in conjunction with single tooth reconstruction with low strain on the patient and minimal risk of complications.
Restoration of occlusal function using osseointegrated implants in the canine mandible reconstructed by rhBMP‐2
Authors: Seto Ichiro , Tachikawa Noriko , Mori Masaji , Hoshino Satoru , Marukawa Eriko , Asahina Izumi , Enomoto Shoji
Published: March 2003

Abstract:Bone morphogenetic proteins have been found to be one of the most promising osteoinductive substances and they are expected to be utilized clinically for the reconstruction of defective mandibles. However, newly formed bone induced by recombinant human bone morphogenetic protein‐2 (rhBMP‐2) has not yet been proven able to withstand the masticatory force applied by oral implants. In this study, we examined the qualitative changes in an rhBMP‐2‐induced mandible from the functional force of osseointegrated oral implants. Segmental (30 mm) bone defects were created in the mandibles of beagles. A poly D,L‐lactic coglycolic acid‐coated gelatin sponge impregnated with rhBMP‐2 was grafted to the resected canine mandible. The new bone was formed 8 weeks after surgery and the Brånemark system fixtures were implanted into the reconstructed mandible. After another 8 weeks, the prosthesis was placed over the oral implants. The prosthesis was maintained in occlusion with the opposing natural dentition for 0, 4, 12, 24, or 48 weeks before the animal was euthanized. The quality of regenerated bone was then evaluated histologically and the osseointegration ratio between oral implants and the bonemeasured. During the first 4 weeks, the ratio remarkably increased from 48.9% to 64.5%. After 48 weeks, the ratio approached about 74.5%. The bone loaded for 48 weeks had undergone extensive remodeling and consolidation; its quality was better and maturer than that of bone that was not loaded. These results indicated that the newly formed bone induced by rhBMP‐2 was able to withstand the masticatory force applied by oral implants and had become as functionally mature as a natural bone.
Fatigue resistance of ITI implant‐abutment connectors − a comparison of the standard cone with a novel internally keyed design
Authors: Perriard Jean , Wiskott W. Anselm , Mellal Aissa , Scherrer Susanne S. , Botsis John , Belser Urs C.
Published: March 2003

Abstract: The Straumann Company has recently supplemented its standard ‘morse‐taper’ configuration with an octagonal internal key. During the restorative phase of implant treatment, this additional feature was designed to ensure positional duplicability between the laboratory and the clinical environments. It was, however, unclear whether this keying mechanism would decrease the mechanical strength of the connection between the implant and the abutment. This applies to keyed male and female parts but also to combinations of the new and the standard designs. Specially constructed specimens analogs representing all three combinations were fitted with a T‐shaped bar, preangled to 15° and subjected to vertical force applications provided by a servohydrolic fatigue tester. The loading frequency was 2 Hz and the maximum cycle number was 106. The data were evaluated using the staircase technique. The specimens were also modeled and analyzed numerically using finite element procedures. The samples' failure locations were recorded and the displacement vs. cycle number plots were patterned in four groups. The fatigue tests and staircase analysis showed no difference in mechanical resistance between the standard and the internally keyed connectors. The finite element models revealed a stress concentration located at the apical edges of the octagonal connector. However, it appeared that this phenomenon was based on computational rather than mechanical grounds. The locations of the failure sites were distributed randomly across the structures, thereby indicating the absence of a locus of minor resistance. The patterns of the displacement vs. cycle number could not be attributed to specific combinations between the standard and the internally keyed designs. It was concluded that both connectors are equal in their mechanical resistance to bending and torquing forces.
Ion implantation: surface treatment for improving the bone integration of titanium and Ti6Al4V dental implants
Authors: De Maeztu Miguel A. , Alava J. Iñaki , Gay‐Escoda Cosme
Published: March 2003

Abstract: Dental implants subjected to surface treatment have shown better bone integration than implants which have only been turned (machined). Three main types of treatment are presently available: the addition of material or coating, the removal of material, and surface modification. Ion implantation corresponds to the third approach. A histomorphometric study is made following the rabbit tibial bone placement of 88 commercial dental implants of pure titanium and Ti6AI4V subjected to surface treatment in the form of different ion implants (C+, CO+, N+, Ne+). Light microscopic, scanning electron microscopic (SEM), electron microsonde (EDS) and X‐ray photoelectron spectroscopy (XPS) studies were made. The results indicate improved bone integration (expressed as percentage bone‐implant contact) in those specimens subjected to ion implantation versus the non‐treated controls, the difference being statistically significant for the groups treated with C+ and CO+. In these groups, XPS showed a Ti‐O‐C junction (bone–implant interface) involving covalent type bonds, these being stronger and more stable than the ion‐type bonds usually established between the titanium oxide and bone.
The accuracy of the Vivacare true pressure‐sensitive periodontal probe system in terms of probing force
Authors: Bergenholtz Axel , Al‐Harbi Nader , Al‐Hummayani Faudia M. , Anton Peter , Al‐Kahtani Saad
Published: March 2003

Background: The Hunter TPS Vivacare periodontal probe was invented to perform consistent, accurate and reliable periodontal examinations “with controlled pressures”.

Aims:

The aims of the present investigation are 3: (1) what is the accuracy of the probing force when various probe heads are used in a correct operation position; (2) what is the effect of over‐ and under‐reading of the operation position on the probing force; (3) what is the accuracy of the probing force when different probe handles are used. The Hunter TPS probe consists of a tip connected to a special spring mechanism, which controls the pressure extended to the probe tip. According to the manufacturer, the force indicator lines coincide at approximately 20 g force.

Method: The test apparatus consisted of an electronic balance, and an electronic caliper. 12 TPS probes tips and 3 handles were selected to test whether there were differences in force between probes. Each probe tip was adapted to the same handle and tested 10 times. In a 2nd test, the TPS‐handles and over‐, accurate‐, and under‐readings were analyzed as to how they affect the probing force. The 12 TPS probe tips were connected to each of the 3 handles and tested 10× for each of 3 handles and levels.

Results: The range in force between TPS probe tips was 8.4 g (p<0.001). For the handles as well as for each of the readings of the operating positions, the differences were small and non‐significant. However, between over‐ and under‐readings, there were statistical significant differences.

Conclusions: The conclusion is that the variation in force between probe tips is high and always above the manufacturer's “approximately” 20 g. As long as the same handle and the same probe tip are used together, and the examiner is reading the markings correct, the. TPS probe is adequate.
Comparisons of clinical and radiographic measurements of inter‐proximal vertical defects before and 1 year after surgical treatments
Authors: Zybutz Michael , Rapoport Darrin , Laurell Lars , Persson G. Rutger
Published: March 2003

Background: Radiographic measurements are often used as a substitute for direct clinical measurements requiring re‐entry surgery for follow‐up outcome studies.

Aims:

(1) To assess the reliability of clinical and radiographic measurements of periodontal defects as compared to direct bone measurements during surgical procedures, and (2) to assess the associations between selected clinical and radiographic measurements of periodontal inter‐proximal defects.

Methods: 57 inter‐proximal periodontal defects were measured at baseline and at 12 months after surgical treatment. Direct measurements during surgery of the distance between the CEJ to the bottom of defects (ABL) were compared with probing to bone (PB), probing attachment level (PAL), and radiographic measurements.

Results: Probing to bone is an accurate measure to assess inter‐proximal bone level as compared to ABL (mean difference: 0.1 mm) and that intra‐oral standardized radiographs underestimate bone level and defect depth by approximately 1.4 mm. The interpretation of periodontal changes between baseline and 12 months after treatment by probing to bone, or PAL measurements, or from radiographic images yield almost identical results (mean difference0.2 mm). For the assessments of changes over time using PB change as the standard, intra‐class correlation (ICC) coefficients varied between 0.52 to 0.90. The best ICC coefficient was found for relative attachment level change assessed by the Florida probe (0.90), and with an ICC value of 0.61 for changes assessed from intra‐oral radiographs. Two‐way analysis of variance failed to demonstrate differences between sets of comparisons.

Conclusions: Both radiographic interpretations of changes over time, and measurements of attachment level changes are reliable in assessing the treatment outcome of inter‐proximal intra‐bony defects when compared to probing to bone changes as the standard method.
Expression of intracellular elastase activity in peripheral neutrophils from patients with adult periodontitis
Authors: Figueredo C. M. S. , Gustafsson A. , Åsman B. , Bergström K.
Published: March 2003

This study aimed to investigate whether circulating neutrophils from patients with periodontitis contain more catalytically active elastase than neutrophils from healthy controls. The amount of IL‐1β in these cells was also analyzed and the correlation with elastase activity was tested. The periodontitis group consisted of 15 subjects with marked periodontal destruction. The healthy control group consisted of 15 subjects with no clinical signs of periodontal destruction. The elastase activity and the IL‐1β content in the cells were measured with flow cytometry using a specific substrate and antibodies, respectively. The plasma concentration of IL‐1β and the total content of antigenic elastase in the crushed cells were measured with an ELISA. The elastase activity per neutrophil was significantly higher in the patients than in the controls, while the total antigenic elastase content did not differ. The % of cells positively stained for IL‐1β was somewhat higher in the patient group. Significantly higher amounts of IL‐1β per sample, estimated by multiplying the % of stained cell with the amount of staining per cell, were found in the patient group. A significant correlation between IL‐Iβ and elastase activity was noted in the patient group (R=0.6, p=0.001), but not in the control group. In conclusion, peripheral neutrophils from patients with adult periodontitis express more active elastase and total amounts of IL‐1. The similar amounts of antigenic elastase suggests that this higher activity is possibly due to some kind of priming /activation already in the circulation.
Analysis of aspartate aminotransferase in gingival crevicular fluid assessed by using PocketWatchTM: a longitudinal study with initial therapy
Authors: Shimada Koichi , Mizuno Tsuyoshi , Ohshio Kaori , Kamaga Masayuki , Murai Seidai , Ito Koichi
Published: March 2003

Aim: The aim of this longitudinal study was to analyze the level of aspartate aminotransferase (AST) in gingival crevicular fluid (GCF) by using PocketWatchTM before and after initial therapy in patients with chronic adult periodontitis and to determine the relationship between AST and conventional measures of periodontal status, such as probing depth, clinical attachment level, bleeding on probing, and gingival index.

Method: A total of 11 patients with chronic adult periodontitis were enrolled. Their periodontal status and AST levels in GCF were measured at baseline and post‐initial therapy (the number of pockets=67), and statistically analyzed.

Results: There was a statistically significant difference in AST levels between diseased periodontal sites (1.2±0.7) and healthy sites (0.3±0.6, p<0.05), and between baseline and post‐initial therapy (p<0.05). Improvements in clinical status were noted following periodontal therapy and there was a corresponding decrease in AST levels.

Conclusions: In conclusion, it is suggested that AST levels may be a useful adjunct in the clinical assessment of periodontal disease sites, since AST level decreases when periodontal status improves.
Acoustic energy affects human gingival fibroblast proliferation but leaves protein production unchanged
Authors: Jones Heather , Feth Lawrence , Rumpf Deborah , Hefti Arthur , Mariotti Angelo
Published: March 2003

Background, aims: Sonic toothbrushes are well‐established in oral home care for plaque removal; however, the effects of low frequency acoustic (sonic) energy released from sonic toothbrushes to the cells of the periodontium have not been investigated. The purpose of this study was to evaluate the effects of sonic energy on human gingival fibroblast proliferation and protein production in cell culture.

Methods: Direct and indirect transfer calibration studies found the fundamental frequency of the Sonicare® sonic toothbrush to be 261 hertz (Hz) with amplitudes ranging from 70 to 104 decibels (dB) in the human periodontium. Using an in vitro delivery system, which coupled a signal‐wave generator with a bone transducer to mimic the energy delivered by the Sonicare® toothbrush, the effects of signal, amplitude and duration were evaluated longitudinally using a gingival fibroblast cell culture model. 8 strains of fibroblasts isolated from healthy human gingiva were seeded at 30,000 cells/35 mm culture dish in minimum essential medium supplemented with 10% fetal bovine serum. To ascertain the relationship of the amplitude and the duration of sonic stimulation to cellular proliferation, gingival fibroblasts were subjected 2× daily to 261 Hz sound at various amplitudes (67–97 dB) for 0, 15, 30, 60, and 120 s on days 1, 3, 5, 7, and 10.

Results: It was found that either 30 or 120 s of sound exposure for 10 days of treatment had significant effects on cell proliferation in comparison to control cultures. Specifically, at day 10, 87 dB at 261 Hz for 30 s 2× daily resulted in a 25.5% increase in cell number (p<0.001), whereas 87 dB at 261 Hz for 120 s twice daily caused a 30.9% decrease in cell number (p<0.001) when compared to control cultures. When cells are stimulated under optimum acoustic conditions for 10 days, there was no difference between the treatment and control groups for collagen (p=0.897) or noncollagen (p=0.697) protein production.

Conclusions: Sonic energy has been shown to both increase and decrease cellular proliferation depending on exposure time; however, during optimum sound‐induced conditions for cellular proliferation, sonic energy had no effect on fibroblast protein production. These data suggest that sonic energy can affect the behavior of cells in culture. Further research into the mechanisms of these changes will provide important information for manipulating cellular behavior.
A sedation technique for implant and periodontal surgery
Authors: Craig David C. , Boyle Carole A. , Fleming Garry J. P. , Palmer Paul
Published: March 2003

Objective: Evaluation of a sedation technique which involved titrating intravenous midazolam to an ‘ideal’ sedation end point, followed by a continuous infusion of propofol. This technique might be a satisfactory alternative to general anaesthesia for implant surgery in anxious patients or when procedures exceed 60‐min duration.

Material and Methods: 20 patients were treated on 23 occasions. A 2‐mg bolus of midazolam was injected intravenously followed after 90 s by 1 mg increments until the patient was adequately sedated. 30 min after this induction with midazolam, a propofol infusion was started at a rate which varied between 0–300 mg/h (0–30 ml/h). The actual infusion rate was adjusted in order to maintain the optimum sedation level which had been achieved using midazolam. The quality of sedation was assessed using Ellis and Sedation scores.

Results: Midazolam dosage varied between 5 and 14 mg. The initial propofol infusion rate was 200 mg/h (20 ml/h) for 21 of the 23 implant surgery treatments.

Conclusion: The sedation technique described takes advantage of the differing pharmacokinetic properties of midazolam and propofol. Initial sedation was achieved using midazolam, this was then maintained using a variable propofol infusion. The shorter distribution and elimination half‐lifes of the latter drug made matching the level of sedation to the patient's needs easier and also provided good short‐term recovery.
Myxoid liposarcoma of the oral cavity with involvement of the periodontal tissues
Authors: Favia Gianfranco , Maiorano Eugenio , Orsini Giovanna , Piattelli Adriano
Published: March 2003

Background, aims: Liposarcoma is the 2nd most frequent soft tissue sarcoma in adults, but it is extremely rare in the head and neck and, particularly, in the oral cavity. We report on a 25‐year‐old female who presented with a periodontal mass, extended from the right upper 3rd molar to the right upper 2nd premolar, covered by intact oral mucosa. The clinical differential diagnosis included peripheral giant cell granuloma, salivary gland neoplasms, squamous cell carcinoma of the gingiva, sarcoma and malignant lymphoma.

Methods: To accurately plan subsequent treatment, an excisional biopsy was performed and a myxoid liposarcoma was diagnosed. Consequently, the patient underwent wide excision of the neoplasm with maxillary en‐block resection.

Results: The post‐operative course was uneventful and the patient is alive and well 8 years after the original diagnosis. The authors stress the importance of considering soft tissue sarcomas in the diagnostic approach to patients with unusual periodontal neoplasms and to plan adequate surgical sampling of the lesion (i.e. excisional biospy).

Conclusions: This appears of pivotal importance as more limited specimens may result in inaccurate pre‐operative diagnosis.
The effect of chewing sugar‐free gum on plaque regrowth at smooth and occlusal surfaces
Authors: Hanham A. , Addy M.
Published: March 2003

Background and aim: Chewing gum has the potential to provide oral health benefits including plaque control. The aim of this study was to determine the effects of chewing sugar free gum on plaque regrowth at buccal, lingual and occlusal surfaces of teeth.

Method and materials:

11 healthy and dentally‐fit dental hygiene students participated in this randomised, single‐blind crossover 4‐day plaque regrowth study. From a zero plaque score on day 1, subjects suspended oral hygiene measures and either chewed gum or did not chew gum over 4 days. Gum chewing was one piece chewed for 30 min 4 × per day. On day 4, subjects were scored for plaque after disclosing from buccal, lingual and unrestored occlusal surfaces.

Results: There was no significant difference in smooth surface plaque scores between the treatments but significantly less plaque accumulated (44%) at occlusal surfaces during gum chewing compared to no gum chewing.

Conclusion: Chewing gum can reduce plaque accumulation at sites of predilection for caries but has little or no effect at sites of predilection for gingivitis.
Oscillating/rotating electric toothbrushes compared: plaque removal and gingival abrasion
Authors: Van Der Weijden G. A. , Timmerman M. F. , Piscaer M. , Ijzerman Y. , Van Der Velden U.
Published: March 2003

Objectives: This study was designed to test the efficacy in plaque removal and the potential for gingival abrasion of 3 electric toothbrushes. The established Braun Oral‐B ‘Ultra’ plaque remover (D9), the Philips/Jordan HP 735, and the newly designed Braun Oral‐B 3D Plaque Remover (3D).

Material and Methods: This study was designed as a split‐mouth, single blind, randomised clinical study consisting of 3 identical experiments with 3 combinations of toothbrushes (exp 1:3D–HP735, exp 2:D9–HP735, exp 3:D9–3D). 40 subjects were requested not to brush their teeth 48 h prior to each examination. At this visit, both the gums and teeth were disclosed for the assessment of baseline plaque and gingival abrasion. Abrasion sites were scored as small (5 mm) or large sites (>5 mm). Plaque was assessed according to the Quigley & Hein index at 6 sites per tooth. The participants brushed 60 s with the 2 brushes, each brush in 2 randomly selected contra‐lateral quadrants.

Results: The increase in number of small abrasions after brushing (exp. 1) was 1.2 versus 1.7 for 3D and HP735, respectively (ns); In exp. 2 the increase was 0.9 for both D9 and HP735. In exp. 3 the increase was 0.4 sites for both D9 and 3D. Comparison of the 3D and HP735 showed a mean plaque reduction of 67% and 54%, respectively (p<0.05); when the D9 and HP735 were compared, a mean plaque reduction of 70% and 58%, respectively, was found (p<0.05); a mean plaque reduction of 74% was found in the comparison of D9 and 3D.

Conclusion: The results show that the potential gingival abrasion after brushing is comparable for all 3 electric toothbrushes. In addition the longer the subjects used the brushes the less abrasion occurred. Finally both 3D and D9 were more effective than the HP735 in removing plaque.
Treatment outcome for IDDM patients in relation to glutamic acid decarboxylase autoantibodies and serum IgG to periodontal pathogens
Authors: Sims Tom J. , Lernmark Åke , Smith Todd , Page Roy C. , Persson G. Rutger
Published: March 2003

Background: Patients with insulin‐dependent diabetes mellitus (IDDM) have elevated risk for periodontitis (PD) relative to subjects without diabetes. Whether refractory PD in IDDM patients is related to autoimmunity as indicated by serum glutamic acid decarboxylase autoantibody GAD Ab levels or to host bacterial immunity as reflected by serum antibody titers to periodontal pathogens is unknown.

Aims: To determine if non‐surgical periodontal treatment outcome differs between GAD Ab‐seropositive and ‐seronegative IDDM patients by assessing the following parameters: (1) pretreatment serum levels of GAD Ab, (2) pretreatment serum IgG titers to key periodontal pathogens, and (3) changes in periodontal pocket probing depth (PDC) after treatment.

Methods: Before and two months after periodontal treatment of 11 GAD Ab‐seronegative and 7 ‐seropositive subjects, PDC was assessed and serum GAD Ab and IgG to Porphyromonas gingivalis (Pg), Bacteroides forsythus (Bf), and Actinobacillus actinomycetemcomitans (Aa) were studied using established radioligand precipitation and enzyme‐linked immunosorbent assays, respectively.

Results: The PDC decrease was significantly better for GAD Ab‐seronegative subjects than for seropositive subjects (median 1.4 mm±0.5 s.d. versus 0.5 mm±0.3 s.d., p<0.03, Mann‐Whitney). GAD Ab levels and PDC were positively correlated (r=+0.71, p<0.05) for sero‐positive subjects but were neutral (r=−0.07) for seronegative subjects. Serum IgG to Pg and GAD Ab levels were positively associated (r2=0.42) in seropositive subjects. Logistic regression analysis confirmed that GAD Ab status was the primary discriminator for PDC (p<0.04).

Conclusion: Detection of elevated GAD Ab levels in combination with elevated IgG titers to Pg before treatment is indicative of IDDM patients with refractory PD.
Untreated periodontal disease in Indonesian adolescents
Authors: Timmerman M. F. , Van der Weijden G. A. , Arief E. M. , Armand S. , Abbas F. , Winkel E. G. , Van Winkelhoff A. J. , Van der Velden U.
Published: March 2003

Background/aims: In an Indonesian population deprived of regular dental care, the experienced progression of disease between baseline (1987) and follow‐up (1994) was investigated in relation to the composition of the subgingival microbiota at follow‐up. At baseline the age ranged from 15 to 25 years. Clinical and microbiological evaluation was completed in 158 of the 167 subjects available at follow‐up.

Methods: Plaque index (PI), pocket depth (PD), bleeding on probing (BOP), and attachment loss (AL) were scored at the approximal surfaces of all teeth and subgingival calculus on the approximal surfaces of the Ramfjord teeth only (number of sites with subgingival calculus: NSC). A pooled sample of the deepest pocket in each quadrant was evaluated using microbiological culture techniques.

Results: At baseline the mean values of the clinical parameters were AL=0.35 mm, PI=1.01, BOP=0.80 PD=3.25 mm and NSC=6.04 and at follow‐up AL=0.75 mm, PI=1.16, BOP=1.19, PD=3.34 mm and NSC=5.85. All parameters except PD and NSC showed a statistically significant increase. At follow‐up the prevalence of Actinobacillus actinomycetemcomitans was 40%, of Porphyromonas gingivalis 67%, of Prevotella intermedia 66%, of Fusobacterium nucleatum 79%, of Bacteroides forsythus 16%, of Campylobacter rectus 4%, and of P. micros 6%. No differences in clinical parameters were found between groups with or without these micro‐organisms. In 129 subjects AL of 2 mm at 1 site was found. Logistic regression showed three significant odds‐ratio’s for experienced progressive periodontitis: Plaque index (12.2), gender (3.4) and Actinobacillus actinomycetemcomitans (2.9).

Conclusions: The results of this retrospective study suggest that plaque is the most important parameter related to experienced disease progression, and that the presence of A. actinomycetemcomitans may be associated with increased chance of disease progression.
Subgingival debridement of root surfaces with a micro‐brush: macroscopic and ultrastructural assessment
Authors: Carey Helen M. , Daly Christopher G.
Published: March 2003

Aim: The aim of this study was to assess the use of a micro‐brush to remove plaque deposits from subgingival, periodontally involved root surfaces in vivo.

Methods: 30 periodontally involved teeth requiring extraction for periodontal or prosthetic reasons in 26 adult patients were utilised. For inclusion, teeth had to display at least 30% bone loss radiographically. Following the establishment of local anaesthesia, grooves were cut on the proximal root surface adjacent to the gingival margin at the line angles. For each tooth, 1 proximal root surface was rubbed with the micro‐brush for 2 min to the depth of the pocket whilst the other root surface acted as an undebrided control. The teeth were then extracted, rinsed in 0.85% NaCl, stained with 2% erythrosine solution and photographed. The amount of erythrosine staining on each subgingival, periodontally involved root surface was assessed by tracing the areas of stain on a colour photograph and scanning the tracings into a computerised image tracing program.

Results: Results were expressed as the % of the periodontally involved root‐surface area that exhibited staining. Stained areas were further examined with the scanning electron microscope (SEM). The undebrided root surfaces each displayed 100% staining. The debrided surfaces (with probing pocket depths of 4–10 mm) displayed mean staining of 16.1% (SD ±7.1%) of the proximal surface area. SEM assessment showed that undebrided root surfaces were covered with thick deposits of bacteria. On debrided surfaces, stain‐free areas were free of plaque whilst areas of faint staining exhibited either no plaque, calculus deposits or scanty, isolated islands of bacteria. Bacteria had been partially removed from the surface of calculus in some areas.

Conclusions: The findings indicate that subgingival debridement with a micro‐brush is effective in removing plaque deposits from periodontally involved root surfaces.
Prostaglandin E2 concentrations in gingival crevicular fluid: observations in untreated chronic periodontitis
Authors: Preshaw Philip M. , Heasman Peter A.
Published: March 2003

Objectives: We set out to monitor gingival crevicular fluid prostaglandin E2 (GCF‐PGE2) concentrations longitudinally in a cohort of subjects with chronic periodontitis, given that we had noted an unexplained trend for GCF‐PGE2 concentrations to gradually increase in control groups and placebo populations in previously published clinical trials.

Material and Methods: 41 adults with moderate‐severe chronic periodontitis were recruited. GCF samples were collected from 8 test sites (with 5–8 mm probing depths and attachment loss) every 30 days for 150 days, and assayed for PGE2. Clinical measurements (probing depths, attachment levels, bleeding on probing) were recorded at days 0 and 150.

Results: A gradual and statistically significant increase in GCF‐PGE2 concentrations was observed over the course of the study, from 40.3 ng/ml to 83.1 ng/ml (p<0.001). When data were expressed as absolute PGE2 content, a similar statistically significant increase from baseline to day 150 was observed (p<0.001). GCF volumes did not vary significantly during the study (p>0.05). Over the same time period, no statistically significant changes in clinical parameters were recorded, with the exception of mean probing depths, which decreased slightly from 5.73 mm to 5.51 mm (p<0.05).

Conclusion: A trend for gradually increasing GCF‐PGE2 concentrations in the absence of any clinical signs of disease progression was noted in a group of patients monitored longitudinally. We suggest that this phenomenon is to be expected in longitudinal clinical trials, and propose a new model for the role of PGE2 in the pathogenesis of periodontal destruction. We feel that if GCF mediators are to be monitored in clinical studies, then both concentrations and absolute mediator content should be calculated, and a standardised sampling protocol should be employed.
How do data from deepest pocket per quadrant relate to full‐mouth scores?
Authors: Timmerman M. F. , Van der Weijden G. A. , Hart A. A. M. , Abbas F. , Winkel E. G. , Van der Velden U.
Published: March 2003

Background: When the subgingival presence of periodontal pathogens is studied in groups of patients or populations, mostly a number of the deepest sites is sampled. The mean clinical parameters of these deep sites are also frequently used as a the descriptor of the clinical situation of these subjects. It can be questioned, whether these 4 deep sites are capable of predicting a full‐mouth situation.

Aim: The purpose of the present retrospective study was to investigate to what extent the experienced progression of periodontitis as measured in the deepest approximal pocket in each quadrant reflects the disease progression at the approximal sites on a full‐mouth level.

Methods: A data set of a 7‐year longitudinal study of 158 young subjects (69 male, 89 female, 15–25 years of age at baseline) was used. Clinical assessments included plaque index (PI), pocket depth (PD) and attachment loss (AL) at baseline (1987) and follow‐up (1994). Measurements were made at the approximal surfaces of all teeth. The deepest pocket in each quadrant was determined at follow‐up. Changes of the clinical parameters between baseline and follow‐up were calculated both as full‐mouth mean scores as well as for these 4 deepest sites. A regression analysis was used to evaluate the relationship between full‐mouth score and the 4 test sites.

Results: For disease progression between baseline and follow‐up, significant correlation coefficients were observed between the 4‐site and full‐mouth mean changes (PD: 0.80, AL: 0.70, PI: 0.77). Regression coefficients were 0.51 for PD, 0.35 for AL and 0.55 for PI. The precision of the estimate for the full‐mouth mean, as predicted by the 4‐site mean, is determined by the residual standard deviation. This was for PD 0.31 mm, for AL 0.31 mm and for PI 0.29. Compared to the between‐patient standard deviation of the full‐mouth means, the residual standard deviations were high.

Conclusion: In the present population, a reasonable to good correlation between full‐mouth and 4‐sites data was observed. However, the high residual standard deviation in the regression analysis illustrates the inaccuracy for the 4‐sites data when used as a descriptive for changes in the periodontal condition on a full‐mouth level. Data evaluating progression of periodontitis based on a limited number of diseased sites should be interpreted cautiously.
Randomised controlled trials and publication trends in periodontal research during 1980–2000
Authors: Sjögren P. , Halling A.
Published: March 2003

Objectives:  To study publication trends, as well as the number and proportion of randomised controlled trials covering different areas of periodontal research (RCT‐Ps).

Material and methods:  The study was based on Medline searches (MeSH terms) for the period 1980– 2000. The RCT‐Ps (n = 675) were examined for relevance for different areas of periodontal research, journals of publication, and the countries of origin.

Results:  In periodontal research the annual number of publications had increased from 162 in 1980 to 440 in 2000. Moreover, clinical trials in periodontal research (CT‐Ps) had increased more than 10‐fold, and RCT‐Ps more than 15‐fold. More than 4 out of 10 RCT‐Ps covered the areas ‘periodontal surgery’ and ‘gingivitis and plaque treatment or prevention’. More than 6 out of 10 RCT‐Ps in total and more than 8 out of 10 RCT‐Ps about ‘periodontal surgery’, were published in two different journals. U.S.A was the most common country of origin of RCT‐Ps, contributing to almost 4 out of 10 RCT‐Ps during 1988– 2000.

Conclusion:  The annual number of RCT‐Ps increased substantially during 1980–2000, and a few clinical research areas predominated. Future research should give priority to areas where clinical evidence is scarce and where high‐quality RCT‐Ps are most needed.
In vitro calibration and validation of a digital subtraction radiography system using scanned images
Authors: Woo B. M. S. , Zee K.‐Y. , Chan F. H. Y. , Corbet E. F.
Published: March 2003

Objectives: To calibrate and validate a digital subtraction radiography system using scanned images for quantification of alveolar bone changes by means of computer‐assisted densitometric image analysis (CADIA) in vitro.

Materials and Methods: Noise levels were determined using 10 standardized periapical radiographs of the same lower molar region in a human dry skull. For validation of the system, radiographs were taken before and after bovine bone particles in measures with increments of 2 mg weighing from 2 to 20 mg were added into each socket of three dry skulls. Radiographs were developed and scanned into a computer with a flatbed scanner. After digitization, the images were subjected to alignment, normalization and subtraction. Appropriate regions of interest (ROIs) were selected and their CADIA values were calculated for the determination of noise levels, and correlations between the CADIA values and the actual bone mass were performed.

Results: When the threshold value was 7, the percentage of pixels deviating from the set threshold value was small (0–11.3%). There were statistically significant correlations between the actual bone mass and the CADIA value for anterior sockets (p<0.001, r2=0.89) and posterior sockets (p<0.001, r2=0.9). For pooled data of both anterior and posterior sockets, the correlation was also statistically significant (p<0.001, r2=0.88).

Conclusions: A high and statistically significant correlation between the actual bone mass and CADIA value was obtained, which suggests that the system could be suitable for the detection of small alveolar bone changes.
Variation in caries and treatment experience in 35–44‐year‐old Lithuanians
Authors: Aleksejuniene Jolanta , Eriksen Harald M. , Holst Dorthe
Published: March 2003

Abstract – Data summarising caries levels differ between countries and often conceal large variations. These differences may reflect variations at individual, group, social and other levels. Caries and treatment experience differences are found to be significantly related to a variety of clinical and non‐clinical factors. Variation in caries within Lithuanian children has been reported and related to background‐, behavior‐, dental care‐ and other factors. Variation in general or related to any factors in adult Lithuanian population has not been studied. The aim of the present study was to estimate variation in caries and treatment experience and relate them to biological‐, psychosocial‐, health‐related, behavioral‐ and dental care related aspects. The existing knowledge from other oral health studies was used to select the factors found of importance in relation to variations in caries scores. The study consisted of clinical and self‐reported data collected from a stratified random sample of 382 individuals (attendance rate 50%). Two statistical approaches, a bivariate and a multivariate, were applied. The two dependent variables DMFT and DS were tested with a set of independent variables. The bivariate analysis revealed significant associations for approximately one half of all variables studied. For multivariate testing, a backward linear multiple regression was used. Forty‐one percent of the variation in DS was explained and 48% in DMFT scores. Differences in scores were related to various factors in the two analyses. The strength and significance of a few relationships differed in both of the analyses. The multivariate testing revealed some strong and significant associations with independent variables which were found to be weak and non‐significant (P>0.05) when tested bivariately and vice versa. Less than half of the variation could be explained in dental caries scores in 35–44‐year‐olds and not only dental care related factors were important. In both of the analyses, the varying degrees of strength (significance levels) give rise to a hypothesis that this incomplete explanation of the variation can be due to interrelated effects of different estimates.
Dentist‐related factors influencing the amount of prosthodontic treatment provided
Authors: Kronström Mats , Palmqvist Sigvard , Söderfeldt Björn , Carlsson Gunnar E.
Published: March 2003

Abstract – Objectives: To evaluate, using multivariate methods, the associations between indicators of the amount of prosthodontic treatment and dentist‐related factors. Methods: Questionnaires were sent to a random sample of 2059 general dentists, response rate was 76%. Two indicators of prosthodontic activity were used as dependent variables: 1) reported weekly working hours used for prosthodontics and 2) reported numbers of produced single crowns, fixed partial dentures, and removable dentures. Independent variables were ‘social and demographic attributes’, ‘job situation’ and ‘attitudes of dentists’. Multiple regression analysis was used in models with continuous dependent variables and logistic regression analysis for categorical dependent variables. Results:‘Weekly working hours used for dental care of adults’ showed a strong association in all models with the dependent variable ‘weekly working hours used for prosthodontics’. Male dentists provided more prosthodontic services than female dentists, even if reporting less time used for prosthodontics. Private practitioners produced more fixed prosthodontics than dentists employed in the public dental health service. Dentists in the public dental health service reported a higher production of removable dentures than private practitioners. Conclusion: The results indicate that factors, besides those in the rational clinical model for decision‐making, e.g. gender and delivery system, play a role in the provision of prosthodontic services.
Service provision patterns by main diagnoses and characteristics of patients
Authors: Brennan D. S. , Spencer A. J. , Szuster F. S. P.
Published: March 2003

Abstract – Service provision patterns may be influenced not only by clinical oral health status leading to a diagnosis and treatment plan, but also by other variables such as patient characteristics. The main aim of this study was to investigate whether associations between services provided and patient factors would persist after controlling for the main presenting diagnosis or condition. A random sample of dentists surveyed in 1993–94 provided a response rate of 74%. Private general practitioners recorded service provision data from logs of 1–2 typical days of practice. Caries (26.5%) was the most prevalent diagnosis, followed by recall/maintenance care (19.0%), pulpal/periapical infection (10.9%), and failed restorations (10.4%). Diagnoses were associated with variation in the percentage of patients receiving services in main areas of service, and also with insurance status, sex and age distributions of patients, and type of visit (chi‐square; P<0.05). Logistic regressions of receipt of services indicated statistically significant associations with patient characteristics and diagnosis categories. Controlling for diagnosis, uninsured patients and those visiting for emergencies had less favourable service patterns (e.g., higher odds of extractions, but lower odds of preventive and crown and bridge services) compared to patients who had dental insurance or visited for check‐ups or other non‐emergency dental problems. The influence of these factors on services provided has implications of public health importance in terms of appropriateness of care and social inequality.