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Dive into the research topics where Stefan Hartwig is active.

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Featured researches published by Stefan Hartwig.


Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology | 2016

Patient and treatment-related risk factors for osteoradionecrosis of the jaw in patients with head and neck cancer

Jan-Dirk Raguse; Jaber Hossamo; Ingeborg Tinhofer; Bodo Hoffmeister; Volker Budach; Basil Jamil; Korinna Jöhrens; Nadine Thieme; Christian Doll; Susanne Nahles; Stefan Hartwig; Carmen Stromberger

OBJECTIVE The purpose of this study was to evaluate risk factors for and the incidence of osteoradionecrosis (ORN) of the jaw in patients with head and neck cancer. STUDY DESIGN This study was a retrospective analysis of the risk for ORN and outcome for 149 of 540 patients with head and neck cancer of the oral cavity (65%), oropharynx (26%), or other head and neck sites (9%) treated with radiotherapy between 2004 and 2009. ORN was graded according to Late Effects of Normal Tissues/Somatic Objective Management Analytic Scale (LENT/SOMA) criteria. RESULTS Within a median follow-up of 41 months (95% confidence interval: 27.4-54.6), 38 patients (25.5%) had developed ORN, 37 patients (25%) had a local recurrence, and 53 patients (36%) had died. The median time to diagnosis of ORN was 14.5 months (range: 3-80), and 79% were diagnosed within 2 years of RT. Eleven of these patients had undergone previous mandibular surgery. Univariate significant risk factors for ORN were any comorbidity, poor oral hygiene, pre-radiotherapy osteotomy, close tumor-to-bone proximity, post-radiotherapy dentoalveolar surgery (DAS), DAS without sufficient wound closure, alcohol consumption, and denture pressure sores. In multivariate analysis, comorbidities, pre-radiotherapy mandibular surgery, poor oral hygiene, and insufficient DAS remained significant. CONCLUSIONS Reducing the risk of ORN calls for maintaining optimal oral hygiene, ensuring good denture fit, receiving proper training in DAS, and helping patients to stop drinking and smoking.


Mycoses | 2016

Adjuvant antifungal therapy using tissue tolerable plasma on oral mucosa and removable dentures in oral candidiasis patients: a randomised double‐blinded split‐mouth pilot study

Saskia Preissner; Isabell Kastner; Eyke Schütte; Stefan Hartwig; Andrea Maria Schmidt-Westhausen; Sebastian Paris; Robert Preissner; Moritz Hertel

Extended use of antimycotics in oral candidiasis therapy gives rise to problems related to fungal drug resistance. The aim of this pilot study was to investigate the efficacy of tissue tolerable plasma (TTP) in denture stomatitis patients. It was hypothesised that (I): erythema and (IIa): complaint remission would be accelerated and (IIb): colony forming unit (CFU) reduction would be improved. The halves of the upper jaws of eight patients were randomly assigned to control (nystatin, chlorhexidine and placebo treatment) and test sides (nystatin, chlorhexidine and TTP administered six times each 7 days). The patients and the investigators, who were different from the therapists, were both blinded. Compared to the control sides, the erythema surface was reduced significantly more extensively on the test sides between 2 and 6 weeks of antifungal therapy (P ≤ 0.05). Visual analogue scale values and the frequency of moderate or heavy growth of Candida post‐treatment did not differ significantly between both sides (P > 0.05). The primary hypothesis was confirmed, which may be interpreted as an accelerated remission. As drug therapy is usually limited to the time in which signs of infection are present, TTP might help reducing antifungal use. Even though the secondary hypotheses were not confirmed, persistence of Candida might be only colonisation.


Mycoses | 2016

Identification of signature volatiles to discriminate Candida albicans, glabrata, krusei and tropicalis using gas chromatography and mass spectrometry

Moritz Hertel; Stefan Hartwig; Eyke Schütte; Bernhard Gillissen; Robert Preissner; Andrea Maria Schmidt-Westhausen; Sebastian Paris; Isabell Kastner; Saskia Preissner

Oral candidiasis is the most frequent fungal infection of the oral cavity. Clinical diagnoses require mycological confirmation, which is time‐consuming in case of culture testing. The aim of the study was to identify signature volatiles to develop a chairside breath test to diagnose oral candidiasis. Headspaces above Candida albicans, glabrata, tropicalis, krusei cultures, and growth media as control were analysed after eight and 24 h using offline gas chromatography and mass spectrometry. The identification of signature volatiles was assisted using various microbial databases. Retrieved volatile patterns enabled Candida species discrimination in vitro. For C. albicans 3‐methyl‐2‐butanone and styrene and for C. krusei a combination of p‐xylene, 2‐octanone, 2‐heptanone and n‐butyl acetate were found to be specific. 1‐hexanol was found in C. tropicalis, but is emitted by a variety of other microorganisms. C. glabrata was characterised through the absence of these volatiles. The development of a breath test is a promising approach in confirming suspicions of oral candidiasis. To confirm the retrieved results in vivo, breath tests in affected and healthy subjects have to be performed.


Journal of Biophotonics | 2016

Bactericidal efficacy of tissue tolerable plasma on microrough titanium dental implants: An in-vitro-study.

Saskia Preissner; Henrik C. Wirtz; Anne-Kristin Tietz; Shady Abu-Sirhan; Sascha R. Herbst; Stefan Hartwig; Philipp Pierdzioch; Andrea Maria Schmidt-Westhausen; Henrik Dommisch; Moritz Hertel

Surface decontamination remains challenging in peri-implant infection therapy. To investigate the bactericidal efficacy of tissue tolerable plasma, S. mitis biofilms were created in vitro on 32 microrough titanium dental implants. Biofilm imaging was performed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The implants were either rinsed with 1% NaCl as negative control (C) or irradiated with a diode laser (DL) for 60 sec as positive control or plasma (TTP60, TTP120) for 60 or 120 sec. Subsequently, colony forming units (CFU) were counted. Post-treatment, implants were further examined using fluorescence microscopy (FM). Median CFU counts differed significantly between TTP60, TTP120 and C (2.19 and 2.2 vs. 3.29 log CFU/ml; p = 0.012 and 0.024). No significant difference was found between TTP60 and TTP120 (p = 0.958). Logarithmic reduction factors were (TTP60) 2.21, (TTP120) 1.93 and (DL) 0.59. Prior to treatment, CLSM and SEM detected adhering bacteria. Post-treatment FM recorded that the number of dead cells was higher using TTP compared to DL and C. In view of TTPs effectiveness, regardless of resistance patterns and absence of surface alteration, its use in peri-implant infection therapy is promising. The results encourage conducting clinical studies to investigate its impact on relevant parameters.


Dental Traumatology | 2017

Drill‐related root injury caused by intraoperative intermaxillary fixation: an analysis of 1067 screw applications

Stefan Hartwig; Andreas Boettner; Christian Doll; Jan Oliver Voss; Moritz Hertel; Saskia Preissner; Jan D. Raguse

BACKGROUND/AIMS Intermaxillary fixation is a standard procedure for the treatment of mandibular fractures or in orthognathic surgery. Predrilling for screws poses the risk of accidental tooth root injury, potentially leading to further pathological processes. Limited evidence about accidental tooth injury during intermaxillary fixation is available due to heterogenous study designs. The aim of this study was to evaluate the risk of root trauma using predrilled transgingival fixation screws and the clinical consequences for the affected teeth. MATERIALS AND METHODS In this retrospective study, the data of open reduction and internal fixation surgery files with intraoperative application of predrilled intermaxillary fixation screws were analysed. The postoperative radiographic images were evaluated for the occurrence of tooth root injury. Patients diagnosed with root injury were clinically followed up with respect to the dental health for the affected teeth. RESULTS A total of 133 radiologically diagnosed tooth root injuries were recorded (12.5% of screws). The median follow-up interval was 16 months (range: 3-77 months). The return rate was 49.5% for all patients. Of these, four of the injured teeth (3%) needed endodontic treatment. No toothache was reported, no tooth was lost, and no negative impact on periodontal health was clinically evident. CONCLUSION Intermaxillary fixation with predrilled transgingival screws is a safe way to manage mandibular fractures. The incidence of tooth root injury is not uncommon, but the adverse side effects are rare and the health of the affected teeth is mostly not compromised.


Dental Traumatology | 2016

Severe tooth loss after root damage caused by predrilled intermaxillary fixation screw: a case report

Stefan Hartwig; Christian Doll; Jan Oliver Voss; Jan D. Raguse

Intermaxillary fixation (IMF) with screws is routinely used as a conservative therapy or to obtain normal occlusion during the surgical procedure of open reduction and internal fixation for treating mandibular fractures. The risk of iatrogenic dental damage caused by interdental drilling is widely known. Several side effects are described, including loss of response to pulp sensibility testing, root fracture, and, loss of the tooth. This is a case report about a young man who had undergone temporary IMF treatment with a single proven root damage. The patient did not appear for follow-up but he presented 5 years afterward with local purulent osteomyelitis concerning the affected and the adjacent teeth. Osteotomy and extraction of two premolars and one molar were necessary for rehabilitation. This case report illustrates the importance of careful use of predrilled IMF screws and the necessity of frequent follow-ups in cases of proven tooth root damage due to IMF treatment.


Journal of Stomatology, Oral and Maxillofacial Surgery | 2018

Clinical characteristics and immunohistochemical analysis of p53, Ki-67 and cyclin D1 in 80 odontogenic keratocysts

Christian Doll; Kevin Dauter; Korinna Jöhrens; Stefan Hartwig; Jan Oliver Voss; Martin Klein; Max Heiland; Jan-Dirk Raguse

OBJECTIVE The aim of this study was to evaluate clinical parameters and expression patterns of Ki-67, cyclin D1 and p53 in odontogenic keratocysts. MATERIAL AND METHODS In this study, fifty-three patients with 80 odontogenic keratocysts were included. The medical records of these patients were reviewed retrospectively. To elucidate the molecular pathogenesis of the disease, the expression of p53, Ki-67 and cyclin D1 was analyzed using immunohistochemistry. RESULTS A total of 53 patients (mean age 38 years) with a median follow-up of 4.2 years (ranging from 4 days to 14.4 years) were evaluated. The rates of recurrence and post-operative complications varied depending on the surgical approach: cystectomy and peripheral ostectomy led to manageable low rates of complications and recurrence frequency. Immunohistochemical evaluation revealed that all lesions were positive for Ki-67 and cyclin D1 expression. The expression of Ki-67 was associated with the degree of inflammation. Cyclin D1 was expressed significantly higher in syndrome-associated keratocystic lesions. In contrast to non-syndromal lesions, all syndromal lesions expressed p53. CONCLUSION This investigation demonstrates that the pathogenesis of syndromal keratocysts appears to differ from sporadic odontogenic keratocysts. Additionally, the primary and recurrent non-syndromal keratocysts have a similar etiology, as no differences in the expression patterns of Ki-67, p53 and cyclin D1 were observed.


Clinical Oral Investigations | 2018

Volatile organic compounds in the breath of oral candidiasis patients: a pilot study

Moritz Hertel; Eyke Schuette; Isabell Kastner; Stefan Hartwig; Andrea Maria Schmidt-Westhausen; Robert Preissner; Sebastian Paris; Saskia Preissner

ObjectivesThe aim of the study was to investigate whether specific volatile organic compounds (VOCs) can be detected in oral candidiasis patients using breath analysis in order to develop a point-of-care diagnostic tool.Patients/methodsBreath samples of 10 diseased patients and 10 subjects carrying no Candida spp. were analyzed using gas chromatography and mass spectrometry. In infected patients, breath tests were performed before and after antifungal therapy.ResultsBreath testing was positive for 143 volatiles in both healthy subjects and diseased patients. Among those, specific signature volatiles known to be emitted by Candida spp. in vitro were not detected. Even though no specific signature was retrieved from the diseased patients, a pattern containing nine compounds (2-methyl-2-butanol, hexanal, longifolene, methyl acetate, 1-heptene, acetophenone, decane, 3-methyl-1-butanol, chlorbenzene) was identified, which showed characteristic changes after antifungal therapy.ConclusionsFocusing on the identified pattern, breath analysis may be applied to confirm the absence of Candida spp. after therapy in terms of a confirmatory test supplementing clinical examination, thereby replacing microbial testing. However, microbial testing will still be needed to initially confirm clinical diagnoses, as no specific signature was found.Clinical relevance: A breath test may help in avoiding extended antifungal administration resulting in resistance development and might be useful in the monitoring of disease recurrences in vulnerable groups.


Otolaryngology-Head and Neck Surgery | 2017

Volatile Organic Compounds in the Breath of Oral Squamous Cell Carcinoma Patients: A Pilot Study

Stefan Hartwig; Jan D. Raguse; Dorothee Pfitzner; Robert Preissner; Sebastian Paris; Saskia Preissner

Objective To assess the feasibility of detecting signature volatile organic compounds in the breath of patients with oral squamous cell carcinoma. Study Design Prospective cohort pilot study. Setting University hospital. Subjects and Methods Using gas chromatography and mass spectrometry, emitted volatile organic compounds in the breath of patients before and after curative surgery (n = 10) were compared with those of healthy subjects (n = 4). It was hypothesized that certain volatile organic compounds disappear after surgical therapy. A characteristic signature of these compounds for diseased patients was compiled and validated. Results Breath analyses revealed 125 volatile organic compounds in patients with oral cancer. A signature of 8 compounds that were characteristic for patients with oral cancer could be detected: 3 from this group presented were absent after surgery. Conclusion The presented results confirmed the hypothesis of an absence of cancer-associated volatile organic compounds in the breath after therapy. In this pilot study, we proved the feasibility of this test approach. Further studies should be initiated to establish protocols for usage in a clinical setting.


Journal of Cranio-maxillofacial Surgery | 2016

The lower trapezius island myocutaneous flap in tunnelled technique to cover complicated tissue defects located between the craniocervical and cervicothoracic junction following spinal surgery

Jan D. Raguse; Marcus Czabanka; Jan Oliver Voss; Stefan Hartwig; Peter Vajkoczy; Pit Jacob Voss; Christian Doll

PURPOSE Stable coverage of complicated defects located between the craniocervical and cervicothoracic junction following wound healing disturbance after spinal surgery can be challenging. Especially in cases where devices are exposed, well-vascularized coverage is required to achieve stable wound conditions. Therefore, the aim of the present study was to evaluate the clinical outcome of the lower trapezius island myocutaneous flap (LTIMF) as a possible treatment option. MATERIALS AND METHODS Four patients with a mean age of 68.8 years (ranging from 50 to 93 years) with wound healing disturbance following spinal surgery leading to defects of the dorsal neck/upper back refractory to conservative treatment and surgical debridement were included. All defects were reconstructed with a LTIMF based on the transverse cervical artery. RESULTS Mean follow-up was 16.5 months (ranging from 5 to 30 months). No major flap failure occurred; minor complications in three patients including lateral superficial skin necrosis were easily handled. In all patients, excellent functional and aesthetic results were achieved. CONCLUSION The lower trapezius island myocutaneous flap represents a reliable treatment option to cover complicated defects located between the craniocervical and cervicothoracic junction following wound disturbance after spinal surgery.

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