Wolfgang Buchalla

University Hospital Regensburg | Uni Regensburg · Poliklinik für Zahnerhaltung und Parodontologie

Introduction: This questionnaire-based investigation aimed to assess Oral Health Behaviour (OHB) in 2-year-old children taking part in a birth cohort study and to identify relationships between general health, socioeconomic as well as psychosocial factors and OHB. Methods: Factors examined were single parent status, migration background, child’s se...

Objectives: Traumatic dental injuries (TDIs) are common, particularly in children and adolescents, and require timely, well-documented treatment for optimal long-term functional and esthetic outcomes. Despite their prevalence, comprehensive data on TDI remain limited. The Regensburg Dental Trauma Registry (RDTR) was established to enable structured...

The pulp is a unique tissue within each tooth that is susceptible to painful inflammation, known as pulpitis, triggered by microbial invasion from carious lesions or trauma that affect many individuals. The host response involves complex immunological processes for pathogen defense and dentin apposition at the site of infection. The interplay of si...

Objectives The aim of this study was to analyze the precipitation of Cerium(III)nitrate hexahydrate [Ce(NO 3 ) 3 ] or Samarium(III)nitrate hexahydrate [Sm(NO 3 ) 3 ] solutions on human enamel with and without a salivary pellicle. Investigated parameters were At%Ce and At%Sm measured using energy dispersive x-ray spectroscopy (EDX) after test soluti...

Since the molecular mechanisms behind adaptation and the bacterial stress response toward antimicrobial photodynamic therapy (aPDT) are not entirely clear yet, the aim of the present study was to investigate the transcriptomic stress response in Escherichia coli after sublethal treatment with aPDT using RNA sequencing (RNA-Seq). Planktonic cultures...

Introduction Chlorhexidine (CHX) is a commonly used antiseptic in situations of limited oral hygiene ability such as after periodontal surgery. However, CHX is also considered as a possible factor in the emergence of cross-resistance to antibiotics. The aim of this study was to analyze the changes in the oral microbiota and the prevalence of antimi...

Introduction: Chlorhexidine (CHX) is a commonly used antiseptic in situations of limited oral hygiene ability such as after periodontal surgery. However, CHX is also considered as a possible factor in the emergence of cross-resistance to antibiotics. The aim of this study was to analyze the changes in the oral microbiota and the prevalence of antim...

Objectives Chewing gums containing antiseptics or other antimicrobial substances may be effective in reducing plaque and gingivitis. Therefore, the aim of this randomized placebo-controlled clinical trial was to investigate the efficacy of a novel antimicrobial chewing gum containing essential oils (cinnamon, lemon, peppermint) and extracts on redu...

Aim To develop a new coculture system that allows exposure of dental pulp cells (DPCs) to Streptococcus mutans and dentine matrix proteins (eDMP) to study cellular interactions in dentine caries. Methodology Dental pulp cells and S. mutans were cocultured with or without eDMP for 72 h. Cell proliferation and viability were assessed by cell countin...

Red-fluorescing dentine indicates bacterial contamination [Lennon et al.: Caries Res 2002;36:315-319]. We investigated effect of removal of red-fluorescent dentine-caries on shear-bond-strength and fracture-mode of 4 adhesive approaches. Sixty-five carious teeth and 50 non-carious controls were distributed into 4 groups: ClearfilTM self-etch (CSE),...

Purpose: This follow-up of a randomized clinical split-mouth study aimed to investigate the influence of selective enamel etching on the long-term clinical performance of partial ceramic crowns (PCCs) luted with a self-adhesive resin cement. Materials and methods: 43 patients received two PCCs (Vita Mark II; Cerec 3D) each for the restoration of...

Objectives Examination of patients claiming adverse effects from dental materials can be very challenging. Particularly, systemic aspects must be considered besides dental and orofacial diseases and allergies. Therefore, the aim of this study was to investigate a cohort of 687 patients reporting on adverse effects from dental materials focusing on...

Objectives Aerosols and splatter are routinely generated in dental practice and can be contaminated by potentially harmful bacteria or viruses such as SARS-CoV-2. Therefore, preprocedural mouthwashes containing antiseptic agents have been proposed as a potential measure for infection control in dental practice. This review article aims to summarize...

Soon after the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, preprocedural mouthwashes were recommended for temporarily reducing intraoral viral load and infectivity of individuals potentially infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in order to protect medical personnel. Particularly, the antis...

Teeth with different chemical compositions can show vastly different physical properties, so knowledge of elemental composition is required to use animal teeth as substitutes for human teeth in research. In vitro, energy dispersive X-ray spectroscopy (EDX), improved by calibration standards and Si3N4-window material, enables determining local eleme...

The objective of this study was to compare the ability of different endodontic irrigation activation methods to enable irrigant penetration, remove the smear layer from root canal walls after preparation, and investigate surface effects on dentine. Root canals of 90 single-rooted teeth were prepared and irrigated with EDTA (17%) and sodium hypochlo...

The aim of our study was to assess the extent to which families followed recommendations, issued by the German society for sleep medicine, for the prevention of sudden infant death syndrome (SIDS) during night-time sleep. Analyzing longitudinal data from a birth cohort located at the University Children’s Hospital Regensburg in Bavaria (Germany), w...

Red fluorophores synthesized by oral bacteria are important for fluorescence-based diagnosis and treatment because they are used as markers for bacterially infected tissue, mature plaque or calculus. A range of porphyrins has been identified as the source of this fluorescence in carious tissue. It is not clear which of these porphyrins are produced...

The accumulation of caries-preventive compounds on sound enamel is crucial in order to improve the inhibition of carious lesion initiation. The aim of this research was to investigate the initial accumulation of cerium, oligopeptide p11-4, and fluoride from NaF or amine fluoride (AmF) on sound enamel in vitro by means of energy dispersive X-ray spe...

Background: Studies show that parents significantly impact their children's health through their cardiometabolic risk profile and health behavior. There is only little information about the prevalence of cardiometabolic risk factors and lifestyle factors among new parents yet. The aims of this study are therefore to evaluate the prevalences of car...

Objectives This randomized prospective split-mouth study evaluated the clinical performance of a novel, tooth-colored, self-adhesive bulk-fill restorative (SABF, 3M) for restoration of class II cavities as compared to a conventional bulk-fill composite (Filtek One, 3M; FOBF) over 36 months. The null-hypothesis was that both materials perform equall...

The need for dental rehabilitations under general anesthesia (DRGAs) is continuously increasing, particularly for dental treatment of children. The present retrospective cohort study aimed to investigate potential risk factors for repeated need of DRGA in a cohort of patients from a private pediatric dental practice. Demographic and anamnestic data...

Antiseptics are widely used in dental practice and included in numerous over-the-counter oral care products. However, the effects of routine antiseptic use on microbial composition of oral biofilms and on the emergence of resistant phenotypes remain unclear. Microcosm biofilms were inoculated from saliva samples of four donors and cultured in the A...

Aim: To investigate the influence of cavity cleaning and conditioning on marginal integrity of directly placed postendodontic composite class-I-restorations in vitro. Methodology: 168 fully intact teeth without caries or fillings received preendodontic composite restorations (class-II) after their extraction. Occlusal endodontic access-cavities...

Background Appropriate health system utilisation during pregnancy is fundamental for maintaining maternal and child’s health. To study the use and determinants of supplementary prenatal screening and diagnostics in Germany this study provides comprehensive data. Methods We obtained data from a recently established prospective German birth cohort s...

Despite the wide-spread use of antiseptics in dental practice and oral care products, there is little public awareness of potential risks associated with antiseptic resistance and potentially concomitant cross-resistance. Therefore, the aim of this study was to investigate potential phenotypic adaptation in 177 clinical isolates of early colonizers...

Despite the widespread use of antiseptics such as chlorhexidine digluconate (CHX) in dental practice and oral care, the risks of potential resistance toward these antimicrobial compounds in oral bacteria have only been highlighted very recently. Since the molecular mechanisms behind antiseptic resistance or adaptation are not entirely clear and the...

Objective Dental pulp cells interact with immunogenic components such as LPS (lipopolysaccharide) or LTA (lipoteichoic acid) released from microorganisms in carious lesions. In the present investigation, the formation of the pro-inflammatory cytokines TNFα and IL-6 in LPS- or LTA-stimulated cells from the dental pulp interface and pulp fibroblasts...

Both the dental pulp and the apical papilla represent a promising source of mesenchymal stem cells for regenerative endodontic protocols. The aim of this study was to outline molecular biological conformities and differences between dental pulp stem cells (DPSC) and stem cells from the apical papilla (SCAP). Thus, cells were isolated from the pulp...

The influence of patient-specific factors such as medical conditions, low-density lipoprotein cholesterol (LDL-C) or levels of 25-hydroxyvitamin D (25OHD) on periodontal diseases is frequently discussed in the literature. Therefore, the aim of this retrospective cross-sectional study was to evaluate potential associations between radiographic bone...

Introduction Primary goal of restorative caries therapy is to preserve pulp vitality and the dentition. Whereas the conventional approach of complete caries removal aims at the elimination of all affected substances without regard to losses of hard tissue or pulp vitality, the innovative concept of selective caries removal (SCR) is characterised by...

Cell homing for dental pulp tissue engineering has been advocated as a feasible approach to regenerate dental pulp in a clinical setting. In order to develop a translational protocol for clinical application, we wanted to determine the effects of disinfectants on the availability of growth factors from the root canal, the amount that can be obtaine...

Objectives In the context of the phase-down of amalgam, development of easily applicable, permanent restorative materials is of high clinical interest. Aim of this study was to evaluate the clinical performance of a novel, tooth-colored, self-adhesive bulk-fill restorative (SABF, 3M Oral Care) and a conventional bulk-fill composite (Filtek One, 3M...

Odontogenic MSCs are vulnerable to LPS-triggered bacterial infections, and they respond by secreting inflammatory mediators, such as IL-6, and with mineralization. Since both processes might be prone to a disturbance of the redox homeostasis, the oxidative stress influence on vital functions of human dental pulp cells (HPCs) was investigated. With...

Die eigenen Zähne zu erhalten, ist in der Regel ein gemeinsames Ziel von Patienten und Zahnarzt. Dieses Bestreben zeigt sich auch darin, dass immer mehr Menschen mit einer höheren Anzahl an eigenen Zähnen älter werden [1]. Maßgeblich an dieser Entwicklung beteiligt sind ein gestiege nes Mundgesundheitsbewusstsein sowie tech nische Fortschritte, die...

Objectives: To determine the clinical performance of partial ceramic crowns (PCCs) luted with a conventional resin cement combined with a universal adhesive without or with selective enamel etching or luted with a self-adhesive resin cement. Methods: In a split-mouth design, each three CAD/CAM-PCCs (Vita Mark II, Cerec) were placed in 50 patients....

Background The aim of this study was to examine the interaction of a multitude of socio-economic, lifestyle, environmental, psychosocial and birth related determinants and their effect on maternal health four weeks after delivery. Methods We used data from a German birth cohort study, the KUNO-Kids health study. Social determinants, as well as the...

Aim of the study was to develop a standardized model system to investigate endodontic irrigation techniques and assess the efficiency of different activation methods on the removal of hard tissue debris in complex root canal systems. Mesial roots of mandibular molars were firstly scanned by micro-computed tomography (µCT) and allocated to three gro...

The antimicrobial photodynamic therapy (aPDT) is a promising approach for the control of microbial and especially fungal infections such as mucosal mycosis. TMPyP [5,10,15, 20-tetrakis(1-methylpyridinium-4-yl)-porphyrin tetra p-toluenesulfonate] is an effective photosensitizer (PS) that is commonly used in aPDT. The aim of this study was to examine...

Objective: In a cohort of 500 patients complaining about adverse effects from dental materials, allergies were found to be contributing to the patients' subjective complaints in only about 14% of the cases. Therefore, the aim of this retrospective study was to investigate an enlarged cohort of 625 patients reporting on adverse effects from dental...

Citrate is important for lipid synthesis and epigenetic regulation in addition to ATP production. We have previously reported that cancer cells import extracellular citrate via the pmCiC transporter to support their metabolism. Here, we show for the first time that citrate is supplied to cancer by cancer-associated stroma (CAS) and also that citrat...

Helicobacter pylori is associated with chronic gastritis, gastric or duodenal ulcers, and gastric cancer. Since the oral cavity is the entry port and the first component of the gastrointestinal system, the oral cavity has been discussed as a potential reservoir of H. pylori. Accordingly, a potential oral-oral transmission route of H. pylori raises...

Objective Histological techniques have long been an integral part of dental research. Especially the processing of complex tissues poses specific challenges, however, literature offers only few technical references. Objectives of this study were therefore to optimize histological staining methods and compile detailed protocols for preparation and s...

Background The objective of this scoping review was to systematically explore the current knowledge of cellular and molecular processes that drive and control trauma-associated root resorption, to identify research gaps and to provide a basis for improved prevention and therapy. Methods Four major bibliographic databases were searched according to...

Brain tissue is known to have elevated citrate levels necessary to regulate ion chelation, neuron excitability, and the supply of necessary energy substrates to neurons. Importantly, citrate also acts as a central substrate in cancer metabolism. Recent studies have shown that extracellular citrate levels in the brain undergo significant changes dur...

Background Dental odontoblasts produce dentin mineralized matrix, trigger immune responses and act as sensory cells. The understanding of the mechanisms of these functions has been particularly restricted due to the lack of odontoblasts being cultivable in vitro. Because of the lack of specific markers to identify cells of the odontoblastic lineage...

Die eigenen Zähne zu erhalten, ist in der Regel ein gemeinsames Ziel von Patienten und Zahnarzt. Dieses Bestreben zeigt sich auch darin, dass immer mehr Menschen mit einer höheren Anzahl an eigenen Zähnen älter werden. Maßgeblich an dieser Entwicklung beteiligt sind ein gestiegenes Mundgesundheitsbewusstsein sowie technische Fortschritte, die ein m...

Interfaces between dentin, enamel and luting agents were characterized using low vacuum Scanning Electron Microscopy (SEM). After smear layer creation, one of three luting agents (RelyX Unicem 2, Clearfil SA Cement and Panavia F 2.0/ED Primer II) was applied on 60 enamel-dentin specimens and dual-cured or self-cured. Specimens were polished (Experi...

Objective: The release of inflammatory cytokines from antigen-stimulated cells of the immune system is inhibited by resin monomers such as 2-hydroxyethyl methacrylate (HEMA). Although the formation of oxidative stress in cells exposed to HEMA is firmly established, the mechanism behind the inhibited cytokine secretion is only partly known. The pres...

Stroke-associated pneumonia is a major cause for poor outcomes in the post-acute phase after stroke. Several studies have suggested potential links between neglected oral health and pneumonia. Therefore, the aim of this prospective observational study was to investigate oral health and microbiota and incidence of pneumonia in patients consecutively...

Introduction In view of increasing resistance against antibiotics and antiseptics, antimicrobial photodynamic therapy (aPDT) may be a promising approach for use in dentistry. The aim of this study was to investigate the mechanism of action of aPDT with the phenalene-1-one derivatives SAPYR and SA-PN-05 as photosensitizers by evaluating bacterial ab...

Objectives: The aims of this study were to investigate the antimicrobial efficacy of antiseptics in saliva-derived microcosm biofilms, and to examine phenotypic adaption of bacteria upon repeated exposure to sub-inhibitory antiseptic concentrations. Methods: Saliva-derived biofilms were formed mimicking caries- or gingivitis-associated condition...

Objectives: SARS-CoV-2 is mainly transmitted by inhalation of droplets and aerosols. This puts healthcare professionals from specialties with close patient contact at high risk of nosocomial infections with SARS-CoV-2. In this context, preprocedural mouthrinses with hydrogen peroxide have been recommended before conducting intraoral procedures. Th...

Selective caries excavation may support pulp preservation. This in vitro study investigated the influence of selective removal of demineralized dentin on marginal integrity of composite restorations as determined by dye penetration. Dentinal caries‐like lesions were produced in the approximal surfaces of 40 extracted human molars (ethylenediaminete...

Antimicrobial resistance is a serious issue for public healthcare all over the world. While resistances toward antibiotics have attracted strong interest among researchers and the general public over the last two decades, the directly related problem of resistance toward antiseptics and biocides has been somewhat left untended. In the field of dent...

Aim To investigate tooth survival and clinical long‐term outcomes up to 26 years following guided tissue regeneration (GTR) therapy in deep intra‐bony defects. Methods Patients from three prospective clinical split‐mouth studies, which investigated the outcomes of GTR therapy, were re‐evaluated 21 to 26 years after surgery independent of the membr...

Background: Synthetic particulate hydroxyapatite (HAP; Ca5(PO4)3(OH)) is used as ingredient in oral care products but its effects on cariogenic biofilms are not clear yet. The primary mode of action of HAP may be acting as a calcium phosphate reservoir when deposited in oral biofilms and release Ca2+ and (hydrogen) phosphate ions upon bacterial ac...

Objectives The aims of this study were (i) to assess cumulative survival rates of class II resin-based composite and compomer restorations in primary molars with a 5-year observation period and (ii) to analyze the influence of different types of anesthesia and different localizations of the restorations in the teeth. Methods Patient charts of a pr...

Fluorescence-aided caries excavation (FACE) is a relatively new fluorescence-based tool allowing specific assessment of the degree of bacterial infection of carious dentin during caries excavation before placement of a restoration. Infected dentin fluoresces red, while dentin which is not bacterially invaded, fluoresces green. This allows the opera...

Abstract One mechanism of action for the anticaries effect of topical fluoridation is through precipitation of CaF2. In this in vitro study energy-dispersive x-ray spectroscopy (EDX) is used as a semiquantitative method to detect enamel fluoride-precipitation under the influence of acidic and neutral pH-value and absence or presence of a salivary p...

Aim To compare penetration depths of endodontic irrigants into dentinal tubules after different activation methods ex vivo. Methodology Root canals of 90 extracted teeth were prepared to size 40, .06 taper. Teeth were divided into 6 groups, and final irrigation was performed with EDTA and sodium hypochlorite as follows: (I) manual dynamic activa...