Hydrophilic implant surfaces ­ a clinical and scientific update (in German) / Hydrophile Implantatoberflächen. Ein Update in Klinik und Forschung

The modification of the implant surface influences implant osseointegration. A physico-chemical means to modify implant surfaces is the creation of hydrophilic surfaces. The aim is an accelerated osseointegration for earlier implant loading and possibly the increase of bone quantity and quality. This review gives an update on the current scientific knowledge on hydrophilic implant surfaces. In vitro, hydrophilic titanium surfaces exhibit different positive effects on hard and soft tissues with significant differences to hydrophobic surfaces. Several cell types and the initial wound healing phase are positively affected. In vivo, an increased osseointegration is detected in the early phase of wound healing. In later stages these significant differences are rarely detectable. Based on clinical trials, early implant loading of hydrophilic surfaces is considered safe and predictable. There is only few data on hydrophilic surfaces in areas of reduced bone quality or quality.

La modification de la surface des implants est l'une des possibilités d'influencer leur ostéo-intégration. L'hydrophilisation des surfaces implantaires est l'une des modifications possibles de leurs propriétés physico-chimiques. L'objectif est d'accélérer la néoformation osseuse périimplantaire pour sécuriser la mise en charge précoce. Il est intéressant de déterminer s'il est possible d'obtenir une augmentation quantitative et une amélioration qualitative de la néoformation osseuse. Cela pourrait aussi présenter des avantages lorsque le site osseux n'est pas optimal. Un nombre croissant de patients souffrent de maladies chroniques, sont soumis à des radiothérapies ou à des traitements médicamenteux systémiques qui influencent le métabolisme osseux. Dans ces cas on voit également des avantages. Ce travail de revue présente une mise à jour sur les études actuelles relatives aux surfaces implantaires hydrophiles. In vitro, les surfaces hydrophiles en titane présentent des propriétés positives sur les tissus durs et mous, avec des différences significatives par rapport aux surfaces hydrophobes. Différents types de cellules intervenant dans la phase initiale de la guérison sont influencées favorablement. In vivo, une ostéo-intégration accélérée est mise en évidence au cours de la phase de guérison précoce, alors que dans les phases ultérieures, ces différences significatives ne sont que partiellement détectables. Sur la base des études existantes, les concepts de mise en charge précoce sont considérés comme sûrs et prédictibles avec les surfaces implantaires hydrophiles. Lorsque la qualité osseuse est réduite, il existe peu de données sur l'ostéo-intégration.

In vivo tooth-color measurement with a new 3D intraoral scanning system in comparison to conventional digital and visual color determination methods.

STATEMENT OF PROBLEM: Three-dimensional (3D) intraoral scanning systems allow for the simultaneous acquisition of 3D information about tooth surfaces and a photorealistic view of the patient's tooth colors. AIM: The goal of this study was the in vivo comparison of a new 3D scanner with a color acquisition mode and conventional visual and digital color measurements. MATERIALS AND METHODS: The colors of 40 teeth of 20 patients were evaluated in seven ways: 1) By dentists using the Vita 3D-Master; 2) By dental technicians using the Vita 3D-Master; 3) With the 3Shape Trios device; 4) With the Vita Easyshade device; 5) With the Vita Easyshade Advance device; 6) With the SpectroShade device; and 7) With the SpectroShade Micro device. Digital measurements of Groups 3 to 7 were repeated three times for each tooth. For all groups, both the CIE Lab values and the Vita 3D-Master values were recorded. The repeatability and relative accuracy of the Vita 3D-Master values were analyzed statistically using Pearson's chi-squared test (α < 0.05). ΔE values were calculated from the CIE Lab values, which served as a basis for performing multidimensional scaling (MDS) and evaluating differences between the groups using the one-way ANOVA with post hoc Tamhane's test (α < 0.05). RESULTS: The results of the ΔE values showed that clinically relevant differences between the evaluation by dentists, dental technicians, and the intraoral scanning device (3Shape) are negligible. The intraoral 3D scanning device (Group 3) and the digital systems (Groups 4 to 7) did not differ significantly in the repeatability of color shade management. The SpectroShade Micro (Group 7) had significantly better relative accuracy than the other devices. CONCLUSIONS: The results demonstrate that intraoral scanning systems can be used to measure both tooth color and tooth surface in 3D. CLINICAL IMPLICATIONS: Intraoral optical scanning devices allow for the acquisition of accurate 3D surface data. Tooth color can be evaluated simultaneously and can be used to determine the color of restorations without requiring additional conventional color-measurement methods.

Pain levels and typical symptoms of acute endodontic infections: a prospective, observational study.

BACKGROUND: This study aimed to identify key symptoms that could be associated with the diagnosis of acute forms of symptomatic apical periodontitis (SAP) and symptomatic irreversible pulpitis (SIP), and to identify a diagnostic algorithm based on these symptoms. METHODS: In this prospective, observational study 173 emergency patients diagnosed with acute pain of endodontic origin and no swelling or fistula were included. Patients were asked 11 specific questions from a checklist with a possible discerning value between acute SAP and acute SIP. Pain levels were recorded using the numeric rating scale (NRS-11). Subsequently, the painful tooth was diagnosed. Logistic regression was used to evaluate the checklist regarding its differentiation between SAP (N = 103) and SIP (N = 70). Moreover, a decision tree was constructed based on recursive partitioning to identify a hierarchy in differentiating symptoms. RESULTS: With identical median NRS-11 scores of 8, the teeth diagnosed with acute SAP and SIP were severely painful. The decision tree analysis resulted in a tree with splits according to pain on cold, perceived tooth extrusion, and pain duration. The overall sensitivity of the tree to detect SAP based on key symptoms was 95 %, its specificity was 31 %. CONCLUSIONS: The best indicator for SAP was a reported absence of pain to cold stimuli. In teeth that did have a history of pain triggered by cold stimuli, the decision tree correctly identified SAP in 72 % of the teeth that felt too high and had hurt for less than one week.

Non- and minimally invasive full-mouth rehabilitation of patients with loss of vertical dimension of occlusion using CAD/CAM: an innovative concept demonstrated with a case report.

Abrasion and erosion are two increasingly common indications for dental treatment. Thanks to modern digital technologies and new restorative materials, there are novel therapeutic approaches to restoring such losses of tooth structure in a virtually non-invasive manner. The case study in this article demonstrates one such innovative approach. The patient's severely abraded natural dentition was restored in a defect-driven, minimally invasive manner using high-performance composite materials in the posterior region, and the "sandwich technique" in the anterior region. The restorations were milled on an optimized milling machine with milling cycles adapted for the fabrication of precision-fit restorations with thin edges.

A 3-dimensional accuracy analysis of chairside CAD/CAM milling processes.

STATEMENT OF PROBLEM: Milling is a central and important aspect of computer-aided design and computer-aided manufacturing (CAD/CAM) technology. High milling accuracy reduces the time needed to adapt the workpiece and provides restorations with better longevity and esthetic appeal. The influence of different milling processes on the accuracy of milled restorations has not yet been reviewed. PURPOSE: The purpose of this study was to investigate the influence of different milling processes on the accuracy of ceramic restorations. MATERIAL AND METHODS: Four groups of partial crowns were milled (each n = 17): Three groups in a 4-axial milling unit: (1) 1-step mode and Step Bur 12S (12S), (2) 1-step mode and Step Bur 12 (1Step), (3) 2-step mode and Step Bur 12 (2Step), and (4) one group in a 5-axial milling unit (5axis). The milled occlusal and inner surfaces were scanned and superimposed over the digital data sets of calculated restorations with specialized difference analysis software. The trueness of each restoration and each group was measured. One-way ANOVA with a post hoc Tukey test was used to compare the data (α = .05). RESULTS: The highest trueness for the inner surface was achieved in group 5axis (trueness, 41 ± 15 µm, P<.05). The 4-axial milling unit exhibited trueness at settings ranging from 61 µm (2Step) to 96 µm (12S). For the occlusal surface, the highest trueness was achieved with group 5axis (trueness, 42 ± 10 µm). The 4-axial milling unit exhibited trueness at settings ranging from 55 µm (1Step) to 76 µm (12S). CONCLUSIONS: Restorations milled with a 5-axial milling unit have a higher trueness than those milled with a 4-axial milling unit. A rotary cutting instrument with a smaller diameter results in a more accurate milling process. The 2-step mode is not significantly better than the 1-step mode.