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Even though research has suggested that supply chain agility and supply chain adaptability are distinct capabilities, little is known about their performance effects and about the contextual conditions under which they are effective. Based on a sample of 143 German firms, we empirically investigate the effects of supply chain agility and supply chain adaptability on cost performance and operational performance using hierarchical regression analysis. We ground our investigation in the dynamic capabilities view and contingency theory. We find that supply chain agility and supply chain adaptability positively affect both cost performance and operational performance. We further find evidence for a mediating role of supply chain agility in the links between supply chain adaptability and performance. Product complexity positively moderates the links between supply chain adaptability and cost performance, and supply chain adaptability and operational performance. The results contribute to the literature by offering a more nuanced understanding of the performance implications of supply chain agility and supply chain adaptability, thereby addressing the crucial question of why their benefits may or may not materialise under varying levels of product complexity. [ABSTRACT FROM AUTHOR]

Objective: The aim of this clinical study was to evaluate whether a correlation exists between the three-dimensional tooth mobility (TM) and Perlotest values for maxillary anterior periodontally involved teeth (pocket depth > 3 mm) before and after periodontal therapy.Method and Materials: Force-related TM was measured in 3 N Intervals in 19 participants as they bit down on a load cell. Perlotest values were evaluated at reproductible measurement points. Both measurement techniques were performed on maxillary central and lateral incisors and canine teeth before periodontal treatment and after a healing period of 3months. The Pearson product-moment correlation coefficient was calculated to determine exploratory associations. Results:The comparison between TM and Perlotest values indicated "high" and "optimum" correlations for maxillary central incisors before and after periodontal therapy. Lateral incisors exhibited "moderate" and "high" correlations, whereas canines exhibited "weak" and "moderate" correlations before and after periodontal therapy.Conclusion: Perlotest values may provide valuable information about quantitative metric tooth mobility in periodontally involved teeth. In future investigations, the study design can expand on various dental fields, such as implantology and traumatology. (Quintessence Int 2013;44:307-316; doi: 10.3290/j.qi.a29153) [ABSTRACT FROM AUTHOR]

This study aimed to evaluate three- and four-unit posterior fixed partial dentures (FPDs) with zirconia frameworks after 5 years of function. Of the initial 30 subjects, 25 patients with 25 FPDs were examined after a mean follow-up period of 62.1 months. Five patients were not available for recall visits. Two FPDs failed before the 60-month evaluation because of framework fracture or delamination of the veneering ceramic after endodontic treatment. The 5-year survival rate was 92%. Based on these results, it can be suggested that zirconia frameworks have sufficient mechanical requirements for use in the stress-bearing posterior region. Major fracture of the ceramic veneer could be related to inadequate framework design or bruxism. [ABSTRACT FROM AUTHOR]

Purpose: To quantify implant displacement upon axial and oblique force application and comparethe effects of bone quality using an in vitro experimental setup. Materials and Methods: One hundred ninety-two implants were inserted into artificial bone block specimens using a drill guide. Ninety-six implants were placed in soft cancellous bone and loaded in 10-N increments up to 80 N in axial and oblique (30-degree angle) directions (n = 48 in each group). The other 96 implants were inserted in dense artificial bone and loaded in axial and oblique directions in the same force increments. Three-dimensional displacement data were recorded for all implants using a noncontact optical image correlation technique based on photogrammetric principles, and the absolute displacement vector was calculated. Results: There were significant differences in the absolute implant displacement in the different bone densities over all load increments. Implant displacement was significantly higher in soft cancellous bone than in dense bone. Axial and oblique loading revealed significant differences in implant displacement in the cancellous specimens, whereas oblique loading showed increased displacement (339 ± 47 ?m at 80 N) compared to axial loading (266 ± 39 ?m at 80 N). However, axial and oblique loading showed no significant differences over all load increments when implants were inserted in dense specimens (absolute displacement with an 80-N load: 147 ± 10 ?m axial and 126 ± 17 ?m oblique). Conclusions: Bone density influenced implant displacement. The loading character (axial versus oblique) significantly influenced implant displacement in soft cancellous bone block specimens only. However, the limitation of the measured displacement values to an in vitro application that did not represent the complexity of vital bone has to be considered. [ABSTRACT FROM AUTHOR]

Objective: Primary stability and micromovement of orthodontic mini-implants depends on a number of factors and influences clinical success or failure. The purpose of this study was to assess the behavior of orthodontic mini-implants upon initial load application. Method and Materials: Orthodontic mini-implants (n = 39) were inserted in the alveolar process of maxillary human cadaver specimens (n = 10). Increasing horizontal forces (up to 2.5 N) were applied, and triggered images were taken in 0.5-N load intervals. Additionally, peri-implant parameters based on micro-CT volume data were recorded. Data were subjected to a two-sided nonparametric Wilcoxon signed rank test, and betweengroup comparisons were assessed with a Mann-Whitney test (α = .05). Results: Initial load application led to displacement beyond elastic recovery of the surrounding bone after force release (P < .001). Cortical thickness and insertion depth, despite numeric differences, did not reveal any statistical differences, while displacement of mini-implants was significantly affected by contact to neighboring teeth (P < .001). Conclusions: Insertion technique and initial load application on orthodontic mini-implants may be regarded as two crucial factors for success, while repeated application of orthodontic force does not seem to increase screw mobility. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objective. The purpose of the present study was to investigate whether or not the quantitative Periotest values of anterior teeth correlate with quantitative metric values of tooth mobility under vertical (VL) and horizontal load (HL) in periodontally healthy subjects. Materials and methods. Thirty-one subjects with good periodontal conditions were included and subjected to two different tooth mobility measurement techniques. Periotest values were measured at reproducible measurement points in the vertical (vPT) and horizontal (hPT) dimensions of upper central and lateral incisors and canine teeth. Using the optical measurement technique (photogrammetry), tooth mobility was measured under load in the horizontal (HL) and vertical loading directions (VL) at different load forces. Pearson's correlation coefficients were used to determine exploratory associations. Results. The comparison between hPT and HL showed no correlations between the two measurements except for 'weak' and 'moderate' correlations for teeth 21 and 23. The analysis of correlations between vPT and VL data showed statistically significant correlations for both the left and right canine teeth that ranged from 'weak' to 'high'. Comparisons between hPT values and VL and between vPT and HL showed significant correlations at a few loading forces only. Conclusion. Quantitative Periotest values cannot be used to draw conclusions about the metric assessment of tooth mobility. For this purpose, the photogrammetric technique could be an additional tool for scientific questions. [ABSTRACT FROM AUTHOR]

Background/aim: The 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. Materials and methods: Periotest® 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 ≤ 0.001). Two different wire-composite splints, 0.45 mm Dentaflex and 0.8 × 1.8 Strengtheners, were inserted and the Periotest® values were measured. Results: The 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. Conclusion: The 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. [ABSTRACT FROM AUTHOR]

Objective: To investigate, in vitro, the effect of time on the 3-dimensional accuracy of open-tray implant impression copings made of polyvinyl siloxane and polyether impression materials., Method and Materials: Reference models with 4 internal connection implants were fabricated. Four sets of 71 direct impressions were made with square impression copings using an open-tray technique. One set of impressions was made with polyether material (material A) and each of 3 polyvinyl siloxane materials (materials B, C, and D). Three-dimensional changes in spatial orientation of the implant analogs were measured over 48 hours using an optical measurement device. Deviation values were summed over 4 points and averaged per impression. Global differences were tested with a nonparametric Kruskal-Wallis test followed by pairwise comparisons using the Mann-Whitney U test., Results: The mean dimensional accuracy of implant impressions significantly differed over time (P < .001). Materials A and B were found to produce comparable results, For materials C and D there was a significant increase in deviations, with a maximum increase at 2 hours. Deviations for material C were comparable to materials A and B at 48 hours. Baseline values were not maintained by any material., Conclusions: Within the limits of this in vitro study, it can be concluded that time cannot be neglected as a factor affecting the accuracy of implant master casts.