Bibliothek

Notizen: Abstract. The aim of the present study was to compare the effects of guided tissue regeneration (GTR) with non-resorbable (ePTFE) and biodegradable barriers (Polyglactin 910). 23 patients provided 29 pairs of similar contralateral periodontal defects (12 pairs of interproximal intrabony lesions. 11 pairs of degree II and 6 pairs of degree III furcation defects). Each defect was randomly assigned to treatment with either non-resorbable (control [c]) or biodegradable (test [t]) devices. At baseline, 6, 12, 18, and 24 months after surgery, clinical measurements (P1I, GI, PPD, PAL-V, PAL-H) were performed. Standardized radiographs were obtained at baseline 12 and 24 months postsurgically. On the radiographs, the linear distances from the cemento-enamel junction (CEJ) to the alveolar crest (AC) and from the CEJ to bottom of the bony defect (BD) were measured using a computer-assisted analysing method (LMSRT). Both treatments revealed a significant (p 〈 0.05) PPD reduction [all defects: −2.97±1.90 mm (t). –2.21±1.73 mm (c); intrabony defects: –4.00±1.96 mm (t), –3.00 ± 1.87 mm (c); degree II furcations: –2.67 ± 0.97 mm (t), –2.08 ± 1.54 mm (c)], PAL-V gain [all defects: 2.02 ± 1.83 mm (t), 1.18 mm ± 1.50 (c): intrabony defects: 3.45 ± 1.48 mm (t), 1.95 ± 1.64 mm (c); degree II furcations: 1.33 ± 0.94 mm (t), 0.92 ± 1.47 mm (c)], PAL-H gain [degree II furcations: 2.22 ± 0.94 mm (t), 1.86 ± 0.60 mm (c)], and radiographic changes [CEJ-AC: −0.56 ± 1.98 mm (t), −0.06 ± 1.19 mm (c); CEJBD: 2.10 ± 1.92 mm (t), 1.24 ± 2.04 mm (c)] after 24 months. For degree III furcations, neither statistically significant PPD reduction nor PAL-V gain was observed. Similar clinical and radiographic results were found 12 and 24 months after surgical treatment using either non-resorbable or biodegradable barriers. More favorable results concerning PAL-V gain in interproximal intrabony defects could be observed with biodegradable barriers after 24 months than using nonresorbable membranes. Whereas interproximal intrabony lesions and degree 11 furcation defects responded favorably to GTR therapy, through-and-through furcations must be looked upon as a contraindication for this regenerative technique. Based on the results of the present study, the use of biodegradable barriers in GTR may be recommended and, thereby, a surgical re-entry to remove nonresorbable barriers can be avoided.

Notizen: Abstract. The aim of the present study was to compare linear measurements of interproximal bone loss on digitized radiographic images after application of different filters to the gold standard of intrasurgical measurements. Immediately before surgery, 50 radiographs of 50 periodontally-diseased teeth exhibiting interproximal bone loss, were obtained by a standardized technique in 33 patients. Intrasurgically, the distances from the cementoenamel junction (CEJ) to the alveolar crest (AC) and from the CEJ to the deepest extension of the bony defect (BD) were assessed. All radiographs were digitized with a flatbed scanner (resolution: 600×1200 dpi). Using the FRIACOM-soft-ware, the linear distances CEJ to AC and CEJ to BD were measured at 50 interproximal lesions from the digitized but unchanged radiographic images and also after use of 7 different basic imageprocessing modes (enhancement of contrast [dynamics], inversion, high-pass, enhancement of gray-level differences, mean value, histogram correction, spreading of grey values) with 11-fold magnification. Neither the measurement of the distance CEJ to AC on the unchanged images nor assessments with any of the filters revealed significant differences from the gold standard. Multivariate analysis of variance showed the respective filter (p=0.009), intrasurgical and radiographic assessments (p〈0.0001), to statistically significantly, influence the difference between intrasurgical and radiographic measurements of the distance CEJ to BD. The underestimation of the intra-surgically assessed distance CEJ to BD by radiographic measurements ranged from 0.3±2.0 to 0.8±1.9 mm. The filter “mean value” underestimated interproximal bone loss statistically significantly more than the digitized but unchanged radiograph (p=0.05). In this study, basic digital manipulations (filters) of radiographic images failed to result in statistically significantly more valid measurements of interproximal bone loss when compared to the unchanged but digitized images. All radiographic assessments on the digitized images except for use of one filter (mean value) came close to the intrasurgical gold standard.

Notizen: Aim: Evaluation of the clinical effect of topical application of doxycycline adjunctive to non-surgical periodontal therapy.Methods: A total of 111 patients suffering from untreated or recurrent moderate to severe periodontitis at 3 different centers (Heidelberg, Frankfurt, Nijmegen) were treated in this double-blind split-mouth study. In each patient, 3 different treatment modalities were assigned randomly to 3 test teeth: scaling and root planing alone (SRP), SRP with subgingival vehicle control (VEH), and SRP with subgingival application of a newly developed biodegradable 15% doxycycline gel (DOXI). At baseline, clinical parameters were measured at all single rooted teeth using a reference splint: PlI, PPD, relative attachment level (RAL-V), GI. 3 strata were generated according to baseline PPD: (i) 5–6 mm, (ii) 7–8 mm, (iii) 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE290204:ges" location="ges.gif"/〉9 mm. Not more than 50% active smokers were allowed to each stratum. 3 and 6 months after therapy re-examination was performed by examiners blinded to baseline data and test sites. The statistical comparison of RAL-V gain and PPD reduction between the treatments was based on a repeated measures ANOVA with correction according to Huynh & Feldt. The comparison of SRP versus DOXI was considered as the main study question.Results: 110 patients finished the 3 months and 108 the 6 months examination. The study did not show adverse effects of VEH or DOXI except for one singular inflammation that occurred 2 months after application of the doxycycline gel. DOXI provided statistically significantly more favorable PPD reduction (SRP: −2.4±1.4 mm, VEH: −2.7±1.6 mm, DOXI: −3.1±1.2 mm; SRP versus DOXI p=0.0001, VEH versus DOXI p=0.0066) and RAL-V gain (SRP: 1.6±1.9 mm, VEH: 1.6±2.2 mm, DOXI: 2.0±1.7 mm; SRP versus DOXI p=0.027, VEH versus DOXI p=0.038) than SRP and VEH after 6 months.Conclusions: Adjunctive topical subgingival application of a biodegradable 15% doxycycline gel was safe and provided more favorable RAL-V gain and PPD reduction than SRP alone and VEH. Thus, by use of topical doxycycline the threshold for surgical periodontal therapy might be moved toward deeper pockets.

Notizen: Objective: The aim of the present study was to compare radiographic assessment of bony fill by digital subtraction analyses (DSA) after periodontal surgery of infrabony and furcation defects with bone level measurements.Methods:  For 19 patients with 19 infrabony lesions and 20 degree II furcation defects, five defects were treated conventionally and 34 defects were treated by regenerative periodontal surgery. At baseline and 60 ± 3 months after surgery, clinical measurements (GI, PPD, PAL-V, PAL-H, PlI) and standardized radiographs were obtained. Furthermore, intrasurgically after reflection of a mucoperiosteal flap and 60 months after surgery after local anesthesia without flap reflection, the distance from the cementoenamel junction (CEJ) to bottom of the bony defect (BD) was measured vertically (PBL-V) and, in furcation defects, horizontally (PBL-H). Pre- and postsurgical radiographs were analyzed by digital subtraction. Bone level gain and DSA results were compared by simple regression analysis.Results: Surgical treatment revealed significant PPD reduction (− 3.45 ± 1.56 mm; P 〈 0.001), PAL-V gain (2.84 ± 1.36 mm; P 〈 0.001), and PBL-V gain (1.68 ± 1.20 mm; P 〈 0.001) in infrabony defects, as well as PPD reduction (− 1.68 ± 1.73 mm; P = 0.001) and PAL-H gain [1.43 ± 1.70 mm (P = 0.001)] in furcation defects after 5 years. A correlation could be found in furcation defects between PBL-H gain and DSA (R2 = 0.34, P = 0.003), whereas the study failed to demonstrate a consistent correlation between PBL-V and DSA in infrabony defects (R2 = 0.12, P = 0.149).Conclusions:  DSA correlates significantly with PBL-H measurements in furcation defects. Thus, either method is a sufficient tool to evaluate bony fill within furcation defects. On the other hand, DSA did not correlate significantly with PBL-V measurements in infrabony defects. This discrepant contribution of DSA in the evaluation of these two types of defects may be explained by the fact that DSA primarily evaluates change in a buccolingual direction.

Notizen: The comparison of the effects of guided-tissue regeneration (GTR) using 2 different biodegradable barriers (polylactide acetyltributyl citrate; polydioxanon) in 3- and 2-wall intrabony defects.Method: The polydioxanon barrier is an experimental membrane for GTR therapy that consists of an continuous occlusive barrier that has a layer of slings on the side that is meant to face the mucoperiosteal flap. 15 patients provided 15 pairs of similar contralateral periodontal defects: 12 predominantly 2-wall and 18 predominantly 3-wall intrabony defects. Each defect was randomly assigned to treatment with either polylactide acetyltributyl citrate (control [c]) or polydioxanon (test [t]) devices. At baseline and 6 months after surgery, clinical measurements (PlI, GI, PPD, PAL-V) were performed.Results: Barrier exposure was commonly observed in both groups (control/test): 5/4 after 7 days, 9/11 after 14 days and 11/12 after 28 days postsurgically. 4 weeks after surgery, 77% of all barriers were exposed to some extent. However, both treatments revealed a significant GI reduction (p〈0.05), PPD reduction [−4.63±1.85 mm (t), −4.17±1.89 mm (c); p〈0.001] and PAL-V gain [3.97±1.17 mm (t), 3.40 mm±1.40 (c); p〈0.001] 6 months after surgery. Regarding GI and PPD reduction as well as PAL-V gain, there were neither statistically significant nor clinically relevant differences between test and control: similar clinical results were found 6 months after surgical treatment using both biodegradable barriers.Conclusions: Based on the results of the present study, the use of both biodegradable barriers in GTR therapy may be recommended.

Notizen: Abstract: The aim of the present study was to evaluate the reproducibility of probing depth (PD) and vertical attachment level (PAL-V) measurements at endosseous implants. Twenty partially edentulous patients who had received 44 Frialit-2 and 30 Astra implants between 1994 and 1996 were examined. At all teeth and implants, clinical parameters (GI, PlI, PD, PAL-V) were measured at 6 sites using the flexible plastic version of the universal explorer TPS probe. At the implants and at teeth that were in similar locations compared to the implants, PD and PAL-V measurements were repeated. For each of the 20 probes that had been used for clinical examination of the 20 patients, the probing force was assessed using a precision balance. As a measure of intraexaminer reproducibility, the following standard deviations of single PD and PAL-V measurements were calculated: Frialit-2: 0.71/0.74 mm; Astra: 0.72/0.75 mm; tooth: 0.59/0.57 mm (PD/PAL-V). Stepwise multiple regression analysis revealed implant/tooth position and GI to influence PD and PAL-V measurement error (P〈0.001). At anterior teeth, a lower variability was observed than at posterior teeth (P〈0.001). PD and PAL-V measurement error were higher at implants than at teeth and influenced by patients. The respective models explained 13% and 17% of the variability of the dependent variable (PD/PAL-V), respectively. Intraexaminer variability of PD and PAL-V measurements at implants tended to be higher than at teeth. Multivariate analysis of variance revealed probe and probe holder to statistically significantly (P〈0.001) influence probing force. However, the differences in probing force between the various probe heads were very small. They reached a maximum of 0.054 N between probe 3 and 14 and may be looked upon as clinically irrelevant.

Notizen: Abstract The furcation involvement of 100 molars in 25 patients suffering from moderate to advanced periodontitis was investigated. The horizontal probing attachment level (PAL-H) within the furcations was assessed 2× within 2 weeks using the pressure-calibrated (0.25 N) flexible plastic universal explorer version of the TPS probe (TPS). To determine the measurement error of PAL-H assessments, the standard deviation of single measurements was calculated. The measurements were repeated using a colour-coded Nabers probe and compared to the TPS assessments. 253 furcations were evaluated (100 buccal, 47 lingual, 53 mesiolingual and 53 distolingual, respectively). For buccale, lingual, mesiolingual and distolingual furcations, the standard deviations were 0.486 mm, 0.598 mm, 0.846 mm, 1.039 mm, respectively. Measurement error was less in buccal and lingual furcations than in mesiolingual and distolingual sites (p 〈 0.005). The agreement of replicate measurements of furcation degrees was excellent for buccal and lingual furcations (weighted κ [standard error] 0.824 [0.076] and 0.779 [0.107], respectively), but only moderate for mesiolingual and distolingual furcations (weighted κ 0.688 [0.096] and 0.544 [0.101). respectively). Only in distolingual sites there was a significant (p 〈 0.025: paired t-test) underestimation of PAL-H by the TPS as compared to the Nabers probe. At all locations the TPS underestimated furcation degrees significantly (p 〈 0.1; Stuart-Maxwell's χ2) as compared to Nabers probe. Measurement error of mesiolingual and distolingual furcations was significantly higher than of buccal or lingual sites. The reproducibility of PAL-H measurements in furcations using TPS is comparable to data published for scorings with colour-coded Nabers probes. Through and through furcations are likely to be underestimated by using the flexible plastic version of the TPS probe. Hence, it seems to be unsuitable for a proper assessment of the degree of furcation involvement.

Notizen: Background:  Controlled-release delivery systems enable the clinician to extend the half-life period of locally administered antibiotics in gingival crevicular fluid (GCF) significantly. The aim of this split-mouth study was to compare the pharmacokinetic profile of two different doxycycline gels (DOXY and ATRI) for topical subgingival application. Pharmacokinetics of both doxycycline gels were analyzed in GCF and saliva.Methods:  In 10 patients suffering from severe periodontitis, 10 pairs of contralateral defects (pocket depth 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE494:ges" location="ges.gif"/〉5 mm/bleeding on probing or 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE494:ges" location="ges.gif"/〉6 mm) were randomly assigned either to the first application of DOXY or ATRI. Fourteen days after the topical application of the first antibiotic gel, the application of the second gel in the contralateral defect took place. Clinical examinations at baseline showed no significant differences between sites treated with DOXY and ATRI. Samples of GCF and saliva were drawn baseline, 2, 5 and 24 h after application, 2, 3, 4, 7, 9 and 11 days after application. Separation and quantitative measurement of both doxycycline-gels was performed with HPLC- and UV-detection at λ=260 nm.Results:  In saliva specimens, time-dependent changes of mean doxycycline concentration were almost identical for both doxycycline-gels and declined from a maximum 2 h after application (ATRI: 6653.90±3096.14 μg/ml; DOXY: 5386.60±1542.02 μg/ml [arithmetic mean±SEM]) to zero values 9 days after application. In crevicular fluid specimens, sites treated with ATRI exhibited a faster decrease of mean doxycycline concentration (1085.30, 264.00, 273.94, and 258.00 μg/ml measured 2, 5, 24, and 48 h after application) than sites treated with DOXY (1388.38, 1300.40, 803.73, and 235.10 μg/ml). The faster decrease of ATRI compared with DOXY could not be proved to be statistically significantly different.Conclusions:  Both doxycycline gels showed pharmacokinetics of controlled-release delivery systems.

Notizen: Abstract. The furcation involvement of 100 molars in 25 patients suffering from moderate to advanced periodontitis was investigated. Presurgically, the horizontal probing attachment level (PAL-H) within the furcations was assessed 2 × within 14 days. To determine the measurement error of PAL-H, the standard deviation of single measurements was calculated. The measurements were repeated intrasurgically and compared with presurgical assessments of furcation degrees. The overall standard deviation of single measurements was 0.739 mm. For buccal, lingual, mesiolingual and distolingual furcations, the standard deviations were 0.602 mm, 0.559 mm, 0.759 mm, 1.099 mm, respectively; measurement error was less in buccal and lingual furcations than in distolingual furcations (p〈0.001). The agreement of replicate measurements of furcation degrees was excellent for buccal, lingual and mesiolingual furcations (weighted κ– coefficients between 0.776 and 0.944), but only moderate for distolingual furcations (κw= 0.706). Multiple linear regression analysis revealed significant influence of furcation depth, width and furcation location on differences of PAL-H (p〈0.05). There was no significant difference between furcation degree as assessed presurgically and intra-surgically.

Notizen: Aim: The aim of the present study was to assess the reproducibility and validity of linear measurements of interproximal bone loss in intrabony defects on digitized radiographic images after application of different filters and magnifications.Methods: Immediately before surgery 50 radiographs of 50 periodontally diseased teeth exhibiting interproximal intrabony defects were obtained by a standardized technique in 50 patients. Intrasurgically the distances from the cementoenamel-junction (CEJ) to the alveolar crest (AC) and from the CEJ to the deepest extension of the bony defect (BD) were assessed. All radiographs were digitized by a flatbed scanner (resolution: 600×1200 dpi). Using the FRIACOM-soft ware, the linear distances CEJ to AC and CEJ to BD were measured at 50 intrabony defects on digitized but unchanged radiographic images and also after use of 2 different basic image processing modes (filters: enhancement of grey level differences, spreading of grey values) with 7-fold and 14-fold magnification by 2 different examiners.Results: Repeated measures MANOVA revealed reproducibility of the measurement of the distance CEJ to AC to be significantly influenced by examiner (p=0.027) and filter in combination with the height of 2 wall component of the intrabony defect (p=0.066). For the distance CEJ to BD filters had significant influence on reproducibility in correlation with vertical angulation difference (p=0.001). On the average in this study radiographic measurements tended to overestimate the amount of bone loss as assessed by intrasurgical measurements (CEJ-AC: 0.74–1.91 mm; CEJ-DB: −0.04–0.77 mm). Validity of measurement of the distance CEJ-AC was shown to be significantly influenced by the depth of the intrabony defect (p〈0.003). Validity of the distance CEJ-BD was significantly influenced by intrasurgically assessed bone loss (p=0.029), horizontal angulation (p=0.066). Filters influenced the validity only in combination with examiner (p〈0.001).Conclusions: In this study, the chosen digital manipulations (filters: spreading, structure) of radiographic images failed to result in statistically significantly more reproducible or valid measurements of interproximal bone loss within intrabony defects when compared to the digitized but unchanged images. All radiographic assessments on the digitized images except for use of enhancement of grey level differences (structure) came close to the intrasurgical gold standard.