Anselm Petschelt

Rigidity of commonly used dental trauma splints

BACKGROUND/AIMSnThe stability of immobilization devices varies from flexible to rigid, depending on the trauma. We evaluated the rigidity of various commonly used splints in vitronnnMATERIAL AND METHODSnAn acrylic resin model was used. The central incisors simulated injured teeth, with increased vertical and horizontal mobility. The lateral incisors and canines stimulated uninjured teeth. Tooth mobility was measured with the Periotest device. Vertical and horizontal measurements were made before and after splinting, and the difference between values was defined as the splint effect. We evaluated 4 composite splints, 3 wire-composite splints, a titanium trauma splint, a titanium ring splint, a bracket splint, and 2 Schuchardt splintsnnnRESULTSnFor all injured teeth and all splints, there was a significant splint effect for the vertical and horizontal dimensions (P < 0.05). For injured teeth, the composite splints produced the largest changes in vertical tooth mobility; wire-composite splints 1 and 2, using orthodontic wires, produced the smallest vertical splint effects. For uninjured teeth, the Schuchardt 1 splint and the bracket splint produced the largest splint effects; wire-composite splints 1 and 2 produced only a slight change in tooth mobility. Composite splints 2 and 3 produced the largest horizontal splint effects for injured teeth, and the 4 composite splints produced the largest horizontal splint effects for uninjured teeth. The most horizontally flexible splints were the titanium trauma splint and wire-composite splints 1 and 2.nnnCONCLUSIONSnAccording to the current guidelines and within the limits of an in vitro study, it can be stated that flexible or semirigid splints such as the titanium trauma splint and wire-composite splints 1 and 2 are appropriate for splinting teeth with dislocation injuries and root fractures, whereas rigid splints such as wire-composite splint 3 and the titanium ring splint can be used to treat alveolar process fractures.

An evaluation of the Periotest® method as a tool for monitoring tooth mobility in dental traumatology

BACKGROUND/AIMnThe Periotest method is a technique for the objective assessment of tooth mobility. The aims of this study were to determine normal Periotest values in the vertical and horizontal dimensions of periodontally healthy teeth in individuals aged 20-35 years and investigate the reliability of Periotest in terms of intra-series and inter-series reproducibility before and after applying a dental trauma splint in vivo.nnnMATERIALS AND METHODSnPeriotest values were measured in periodontally healthy dental students (n = 33; mean age 24.7 years) at reproducible measuring points in the vertical and horizontal dimensions, before and after splint insertion. Three readings were taken per series to observe the intra-series reproducibility; three series were measured to test inter-series reproducibility (Friedman-test; P <or= 0.001). Two different wire-composite splints, 0.45 mm Dentaflex and 0.8 x 1.8 Strengtheners, were inserted and the Periotest values were measured.nnnRESULTSnThe median Periotest values before splinting were: canines -2.5, lateral incisors -0.9, and central incisors 0.0 for the vertical dimension, and canines 1.1, lateral incisors 3.2, and central incisors 3.6 for the horizontal dimension. The intra-series and inter-series Periotest values were highly reproducible.nnnCONCLUSIONnThe Periotest method provides highly reproducible results. Focused on dental trauma, the method can be applied diagnostically during the splint and follow-up period and for evaluating splint rigidity.

In vitro splint rigidity evaluation – comparison of a dynamic and a static measuring method

OBJECTIVESnThe aim of this in vitro study was to investigate a dynamic and static tooth mobility assessment method in terms of reproducibility and correlation.nnnMATERIALS AND METHODSnA custom-made artificial model was used. The central incisors simulated injured teeth with increased mobility, and the lateral incisors served as uninjured teeth with physiological mobility. To assess tooth mobility, three consecutively repeated measurements were taken, in the vertical and horizontal dimensions before and after splinting, using the Periotest method as well as the Zwick universal testing machine. Reproducibility of the measurements was tested using anova and the Bonferroni post hoc test (α = 0.05). Correlation was analysed using Spearmans rank correlation (α = 0.05).nnnRESULTSnNo significant differences were found when comparing the three consecutively taken Periotest values and the vertical Zwick values (P > 0.05). In the horizontal dimension, the first Zwick values differed from the second and third values (P < 0.05). Only a few random correlations (P < 0.05) were found when comparing the two assessment methods. Horizontal and vertical measurements within one method did not correlate (P > 0.05).nnnCONCLUSIONSnThe Periotest and vertical Zwick values are highly reproducible. The measurements of the two methods do not correlate; therefore, a conversion of Periotest values into metric displacement data is not feasible. The two methods provide different valuable information about tooth mobility. The Periotest method describes the damping characteristics of the periodontal ligament while the Zwick method reveals quantitative metric values.

Restoration of endodontically treated teeth with major hard tissue loss - influence of post surface design on pull-out bond strength of fiber-reinforced composite posts

AIMnThe aim was to evaluate the influence of post surface design and luting system on bond strength of quartz-fiber-reinforced composite posts (QFRCPs) luted to root canal dentin.nnnMATERIALS AND METHODSnSingle-rooted bovine teeth (nxa0=xa0650) were randomly assigned (13 groups, nxa0=xa050), sectioned, endodontically treated, filled, and post space (length 8xa0mm) prepared. Custom-made plain-surfaced fiber posts (PSXRO) and (both RTD) macroretentive Macro-Lock Post Illusion X-RO (MLXRO) were inserted into the post spaces using six luting systems: Ketac Cem (KC), Fuji Plus (FP), RelyX Unicem, Multilink Primer_Multilink, Sealbond Ultima_CoreCem, and LuxaBond_LuxaCore Z. As control, a titanium post was cemented with KC. After water storage (24xa0h, 37°C), pull-out test was performed, followed by failure mode assessment. Bond strength was calculated in MPa and analyzed using anova, Dunnett-T3-test, and Students t-test with Bonferroni correction.nnnRESULTSnPost design and luting system significantly influenced the bond strength [MPa] (Pxa0<xa00.05). Compared with the control 4.3 (1.5), all test groups exhibited higher bond strengths (Pxa0<xa00.05), except for group PSXRO/KC 4.2 (1.0). The remaining bond strengths were PSXRO: FP 8.6 (1.5), RelyX Unicem 10.4 (3.4), Multilink Primer_Multilink 12.7 (3.0), SealBond Ultima_CoreCem 12.7 (3.0), LuxaBond_LuxaCore Z 15.7 (2.5), and MLXRO: KC 7.2 (2.2), FP 13.4 (2.5), RelyX Unicem 9.2 (2.9), Multilink Primer_Multilink 12.5 (4.5), SealBond Ultima_CoreCem 13.7 (4.6), LuxaBond_LuxaCore Z 20.6 (2.2). The bond strengths of MLXRO were higher than those of PSXRO when luted with KC, FP, and LuxaBond_LuxaCore Z (Pxa0<xa00.05).nnnCONCLUSIONnThe post surface design and luting system selection influenced the bond strength of conventionally and adhesively luted QFRCPs to bovine root canal dentin.

Influence of wire extension and type on splint rigidity – evaluation by a dynamic and a static measuring method

OBJECTIVESnTo evaluate the influence of wire dimension and wire length on the splint rigidity of wire-composite splints in vitro.nnnMATERIALS AND METHODSnA custom-made artificial model was used. The central incisors simulated injured teeth with increased mobility, and the lateral incisors and canines served as uninjured teeth with physiological mobility. To assess horizontal and vertical tooth mobility before and after splinting, the Periotest and Zwick methods were applied. Teeth 13-23 were splinted using wire-composite splint 1 (WCS1; Dentaflex 0.45 mm) and wire-composite splint 2 (WCS2; Strengtheners 0.8 × 1.8 mm). Splint length was varied by successively shortening the wire. The influence of wire dimension was tested using t-test and Wilcoxon-Mann-Whitney test with the Bonferroni-Holm procedure (α = 0.05). To test the influence of wire length, anova and Kruskal-Wallis tests as well as Tukey range and Wilcoxon test with Bonferroni-Holm procedure were applied (α = 0.05).nnnRESULTSnWire dimension significantly influenced splint rigidity (P < 0.05). The wire length significantly influenced the splint rigidity of WCS1 in the horizontal dimension and WCS2 in the horizontal and vertical dimensions (P < 0.05). Splint rigidity was significantly reduced when splinting only injured teeth compared with splints including uninjured adjacent teeth (P < 0.05). No differences were found between splints including one or two uninjured teeth on each side (P > 0.05).nnnCONCLUSIONnWCS1 is flexible compared with the more rigid WCS2. The wire length influences the rigidity. To ensure adequate fixation and reduce the risk of enamel damage during splint removal, the splint should include only one uninjured tooth bilaterally.

Rigidity evaluation of quartz‐fiber splints compared with wire‐composite splints

AIMnTo evaluate the influence of reinforcement material on in vitro dental splint rigidity.nnnMATERIALS AND METHODSnu2002A custom-made artificial model was used. The central incisors simulated injured teeth with increased mobility, and the lateral incisors served as uninjured teeth with physiologic mobility. The Periotest and Zwick methods were used to assess horizontal and vertical tooth mobility before and after splinting, and relative splint effect (SpErel) was calculated. Teeth 12-22 were splinted using two wire-composite splints (WCS), WCS1 (Dentaflex 0.45mm), and WCS2 (Strengtheners 0.8×1.8mm) as well as four quartz-fiber splints, QS1 (Quartz Splint UD 1.5mm), QS2 (Quartz Splint Rope 1.5mm), QS3 (Quartz Splint Woven 2.5mm), and QS4 (dry fibers 667 tex). The influence of the splint type was evaluated using anova, Tukey range, and the Dunnett-T3 test (α=0.05). To test the influence of initial tooth mobility, the t-test was applied (α=0.05).nnnRESULTSnu2002Reinforcement materials significantly influenced splint rigidity (P<0.05). The horizontal and vertical SpErel of WCS1 compared with WCS2 and QFSs1-4 was statistically significant (P<0.05). Significant differences were found when comparing the horizontal SpErel of WCS2 with WCS1 and QSs1-4 (P<0.05). SpErels of the injured and uninjured teeth showed significant differences (P<0.05).nnnCONCLUSIONnu2002WCS1 is flexible compared with the more rigid WCS2 and QSs1-4. Initial tooth mobility influences SpErel. The flexible WCS1 can be recommended for splinting dislocation injuries whereas the semi-rigid/rigid WCS2 and QS1-4 can be used for horizontal root fractures and alveolar process fractures. The QS1-4 provide good esthetic outcome.

Restoration of endodontically treated teeth with major hard tissue loss--bond strength of conventionally and adhesively luted fiber-reinforced composite posts.

AIMnTo evaluate the influence of the luting system on the pull-out bond strength of conventionally and adhesively luted fiber-reinforced composite posts (FRCPs).nnnMATERIAL AND METHODSnOne hundred extracted bovine teeth (Di 3) were endodontically treated and randomly assigned to nine test groups and one control group (n = 10) according to luting system. After preparing the post cavities (8 mm), the custom-made FRCPs were inserted using conventional glass-ionomer cement (Ketac Cem), resin-reinforced glass-ionomer cement (Meron Plus and Fuji Plus), self-adhesive resin cement (RelyX Unicem and BisCem), self-conditioning adhesive and resin cement [Multilink Primer + Multilink and AdheSE + DC Activator + MultiCore Flow, or etch-and-rinse adhesive and resin cement (SealBond Ultima + CoreCem, and LuxaBond + LuxaCore Z). As a control, custom-made titanium posts were inserted with Ketac Cem. After water storage (37°C, 24 h, dark), the pull-out test was performed, followed by failure mode evaluation. The data were statistically analyzed (α = 0.05) using analysis of variance and the Dunnett T3 post hoc test.nnnRESULTSnLuting system type and identity significantly influenced bond strength (P < 0.001); the bond strengths of all luting systems except Ketac Cem, MeronPlus, and BisCem were significantly higher than the control (4.4 ± 1.1 MPa). RelyX Unicem (12.0 ± 3.0 MPa) and LB + LCZ (14.8 ± 2.3 MPa) generated the highest bond strengths. The clinical application was demonstrated by restoring a traumatized tooth with extensive coronal destruction and thin root canal walls, using a FRCP combined with direct composite build-up.nnnCONCLUSIONnLuting system selection significantly influenced the bond strength of conventionally and adhesively luted FRCPs to bovine root canal dentin.

Development of new artificial models for splint rigidity evaluation

AIMnWe developed two versions of an artificial model and assessed their suitability for splint rigidity evaluation. These models allowed the simulation of traumatically loosened teeth and the use of the acid-etch technique for splint application.nnnMATERIALS AND METHODSnA straight and half-round arch bar model with bovine tooth facets were manufactured. Using the Periotest method, tooth mobility was evaluated before (PTVpre) and after (PTVpost) splinting. Two types of previously investigated wire-composite splints, WCS1 (Dentaflex 0.45 mm; Dentaurum) and WCS2 (Strengthens 0.8 × 1.8 mm; Dentaurum), were applied (n = 10) to each model. The relative splint effect (SpErel = ΔPTV/PTVpre) was calculated, and the working times for the models and splints were evaluated. Students t-test and the Mann-Whitney U-test were employed with Bonferroni correction for multiple hypotheses.nnnRESULTSnWhen comparing the relative splint effect of the injured central incisors between the models within one splint type, differences were only found for tooth 21 (WCS2; P < 0.008); for comparisons of splints within one model type, differences were detected for both incisors and model types (P < 0.008). With the straight model, significantly less working time was necessary (P < 0.05).nnnCONCLUSIONnUsing these models for in vitro splint rigidity evaluation, the splints can be applied with the acid-etch technique and tooth mobility can be individually adjusted. WCS1 is considered flexible compared to the more rigid WCS2. The results from the straight and the round model were predominantly closely related to each other. In terms of working time, the straight model is superior to the round model.

Influence of adhesive point dimension and splint type on splint rigidity – Evaluation by the dynamic Periotest method

AIMnTo evaluate the influence of adhesive point dimension and splint type on the rigidity of wire-composite splints in vitro.nnnMATERIALS AND METHODSnA custom-made artificial model was used. The two central incisors served as injured teeth (degrees of loosening III and II) and the two lateral incisors as non-injured teeth (physiological mobility). Horizontal and vertical tooth mobilities were investigated before and after splinting with the Periotest(®) method; the percent change was taken as the relative splint effect. Teeth were splinted with three types of wire-composite splints: Dentaflex (0.45xa0mm), Strengtheners (0.8xa0×xa01.8xa0mm), and Dentaflex completely covered with composite. Four adhesive point dimensions (2, 3, 4, and 5xa0mm) were evaluated. Normal distribution was tested with the Kolmogorov-Smirnov test. Differences were evaluated with the anova and post hoc tests for pair-wise comparisons. Significance level was set at 0.05.nnnRESULTSnThe adhesive point dimension did not influence splint rigidity, in general ( P xa0=xa00.288). Significant effects were found in non-injured teeth with the Dentaflex ( P xa0<xa00.001) and in injured teeth with the Strengtheners ( P xa0<xa00.001). The Strengtheners splint rigidity increased significantly with increasing adhesive point dimensions. The three splints showed significantly different effects at 5-mm adhesive point dimension ( P xa0<xa00.001).nnnCONCLUSIONnSplint rigidity for injured teeth was influenced by adhesive point dimension only when splinting with Strengtheners. We recommend adapting splint rigidity by selecting different wires and reducing the adhesive point dimension to a minimum. Dentaflex can be used for flexible splinting, Strengtheners, and composite covered Dentaflex for rigid splinting.

Influence of attachment and bone loss on the mobility of incisors and canine teeth

Abstract Objective. The purpose of this clinical study was to evaluate the correlation between tooth mobility (TM), crown-to-root ratio (CRR) and clinical attachment loss (CAL) in periodontally-compromised participants. Materials and methods. While slowly biting on a load cell, the mobility of the upper incisors and canine teeth of 20 volunteers was measured using a photogrammetric measurement technique. An automated software program recorded the force-related three-dimensional TM at 3-N intervals. CAL was assessed clinically and CRR values were assessed radiographically. For each contralateral pair of teeth (central, lateral incisor, canine) and for each main level of force, the Pearson product-moment correlation coefficient between TM and CRR and between TM and CAL was computed. Correlations were considered statistically significant at p < 0.05. Results. Statistically significant positive correlations were found between TM and CRR for incisors and canines for each main level of force, whereas canines had the lowest correlation. Statistically significant positive correlations were also found between TM and CAL for the central and lateral incisors at each main level of force. Canines showed no significant correlation between CAL and TM, regardless of force level. Conclusion. The loss of attachment and bone seem to have more influence on the mobility of incisors than canines.