Guided biopsy of osseous pathologies in the jaw bone using a 3D-printed, tooth-supported drilling template

Suspicious radiological findings in the jaw bone require histopathological examination for the confirmation of a diagnosis. As pathologies in this region are difficult to reach or are in close proximity to relevant anatomical structures, e.g. tooth roots or nerves, they often represent a challenge. Such factors may adversely affect the predictability of the surgical outcome of a biopsy of the osseous tissues. This technical note introduces a novel method for performing a digitally planned, guided biopsy. For this purpose, a cone beam computed tomography scan and an intraoral scan are superimposed using specific planning software. The resulting three-dimensionally printed, tooth-supported drilling template is designed for a trephine biopsy. It allows a precise, minimally invasive approach, with an exact three-dimensional determination of the biopsy location prior to surgery. The risk of devitalization of the neighbouring teeth or possible damage to the nerve structures can be minimized. Furthermore, a small access flap can be sufficient. In summary, the method of bone biopsy presented here allows high precision and greater predictability for biopsy sampling and is minimally invasive for the patient

Accuracy of guided biopsy of the jawbone in a clinical setting: A retrospective analysis

The aim of this study was to investigate the accuracy of a previously described technique for guided biopsy of osseous pathologies of the jawbone in a clinical setting. The data sets of patients who had undergone guided biopsy procedures were retrospectively examined for accuracy. Digital planning of the biopsies and manufacturing of the tooth-supported drilling template were performed with superimposed cone beam computed tomography and intraoral scans using implant planning software. After a trephine biopsy was taken using the template, the postoperative low-dose cone beam computed tomography was analyzed for accuracy using the planning software with the corresponding (digitally-planned) biopsy cylinder. The mean angular deviation was 4.35 ± 2.5°. The mean depth deviation was -1.40 ± 1.41 mm. Guided biopsy seems to be an alternative to a conventional approach for minimally invasive and highly accurate jawbone biopsy

Value of FDG-PET/MR in Oral Focus Assessment in Head and Neck Cancer Patients-A Feasibility Study

FDG-PET/MR is a hybrid imaging modality used for the staging and restaging of advanced head & neck cancer (HNC) patients. Their treatment typically involves radiation therapy, which requires previous dental focus assessment. The aim of this study was to analyze if staging FDG-PET/MR is a valuable tool for oral focus assessment. For this purpose, FDG-PET/MR findings, such as metabolic activity of periapical radiolucencies and marginal periodontitis, were retrospectively compared with conventional standardized dental focus assessment, including dental radiographs and clinical assessment of 124 teeth in seven patients. Increased FDG uptake of periapical lesions was found in one out of 23 lesions. Increased FDG uptake of the marginal periodontium was recorded in one out of 34 lesions. In summary, standardized dental focus assessment by panoramic radiography and periapical radiographs may be enriched by information from FDG-PET/MR, showing active inflammation in dental foci. However, many dental foci have no correlate in FDG-PET/MR. The treatment decision for oral foci may benefit from the visualized presence or absence of metabolic activity on FDG-PET/MR

FDG-PET/CT for oral focus assessment in head and neck cancer patients

OBJECTIVES To compare oral and maxillo-mandibular inflammatory foci on standard oral radiographs (OPT, periapical radiograph) with available fluorine-18-labelled fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) data and to discuss whether additional metabolic information derived from FDG-PET/CT can support oral care specialists when performing oral focus examinations. MATERIALS AND METHODS Data from 23 patients with head and neck cancer who underwent FDG-PET/CT and panoramic and periapical radiography in close succession before first-line radiotherapy and/or chemotherapy were included in this exploratory retrospective study. Periapical lesions and marginal periodontal inflammation on FDG-PET/CT scans and standard oral radiographs were analysed and compared with regard to metabolic activity on FDG-PET/CT in comparison to recorded clinical symptoms and radiological scores. Additionally, inflammatory maxillo-mandibular pathologies were analysed using FDG-PET/CT. RESULTS The maximum standardised uptake value (SUV$_{max}$) in FDG-avid marginal periodontal sites could not be conclusively associated with the radiologically recorded severity of marginal bone loss, but a potential positive correlation was identified. No association was found either between the metabolic activity of periapical lesions and their extent, as recorded on standard oral radiographs, or regarding clinical symptoms (percussion test). Most maxillo-mandibular pathologies did not show increased FDG uptake. CONCLUSIONS FDG-PET/CT provided additional metabolic information that can help clinicians identify lesions with increased inflammatory activity. The incorporation of available oral FDG-PET/CT findings into the primary oral focus assessment may allow for more accurate oral focus treatment. CLINICAL RELEVANCE FDG-PET/CT provides valuable metabolic information for oral care specialists. The detection of inflammatory oral processes using FDG-PET/CT facilitates treatment

Hydrophilic implant surfaces – a clinical and scientific update (in German)

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

Alveolar ridge preservation with autologous particulated dentin-a case series

Abstract Introduction Ridge preservation can be performed with autologous bone, alloplastic bone substitute material or a combination of both. Dentin is similar to bone in its chemical composition. In its use as bone substitute material, it undergoes a remodelling process and transforms to bone. The presented case report introduces a technique in which the extraction socket is augmented with autologous, particulated dentin. Material and methods The fractured, non-savable mesial incisor of the upper jaw was carefully extracted in axial direction. After the extraction, the tooth was cleared from remaining periodontal tissue. The vital pulp tissue or a root canal filling, enamel and cementum were also removed. Following the particulation of the remaining dentin in a bone mill, the dentin particles were immediately filled orthotope into the alveolar socket. The soft tissue closure was performed with a free gingival graft of the palate. Results After an observation period of 4 months, an implant was placed in the augmented area, which osseointegrated successfully and could be restored prosthodontically in the following. The results of this method showed a functional and aesthetic success. Conclusion The pre-implantological, autologous ridge preservation with dentin could be performed successfully. For the establishment of dentin as augmentation material for jaw augmentation procedures, a prospective, clinical trial is now necessary

Success rate 1 year after apical surgery: a retrospective analysis

PURPOSE The aim of the current study was the retrospective analysis of the outcomes of teeth treated with apical surgery after a 1-year follow-up period. Furthermore, potential factors associated with the success rate were investigated. METHODS All patients were treated at the Clinic of Cranio-Maxillofacial and Oral Surgery at the University of Zurich between 2010 and 2017. To be eligible for inclusion, all patients were required to have undergone apical surgery with a retrograde root-end filling, and a 1-year follow-up examination at the University of Zurich. Treatment success at the 1-year follow-up time-point was defined as an absence of clinical complaints and radiographically determined healing. Parameters that were analysed included tooth localisation, periapical index of the preoperative lesion, administration of antibiotics, smoker status, histopathology of the apical lesion, radiographically determined sufficiency of root canal treatment pain and clinical signs of inflammation at the initial examination. RESULTS A total of 81 teeth fulfilled all the inclusion criteria. At the 1-year follow-up, 91.4% of the teeth exhibited successful clinical and radiographic healing. The type of tooth was significantly associated with the success of the surgery (p = 0.006), but radiological severity of periapical inflammation, lesion histopathology, administration of antibiotics, smoker status, the quality of the root canal treatment, and preoperative pain and clinical signs of inflammation were not. CONCLUSION The results of the present study suggest that apical surgery with retrograde root-end filling is a reliable therapy for the preservation of teeth. Furthermore, there are limited factors that affect the treatment outcome

Sensibilitätsstörung des Nervus mandibularis

Die Wurzelspitzen der Unterkiefermolaren haben häufig eine enge Lagebeziehung zum Kanal des Nervus alveolaris inferior. Bei einer Wurzelkanalbehandlung kann es durch Überinstrumentierung oder Überstopfen von Wurzelkanalfüllmaterial zu einem Nervtrauma mit anschließenden Sensibilitätsstörungen kommen. Anhand eines Fallberichts über den Behandlungsverlauf bei einer jungen Patientin, die aufgrund einer Anästhesie in der rechten unteren Kinnregion in die Klinik für Mund-, Kiefer- und Gesichtschirurgie und Oralchirurgie überwiesen wurde, werden mögliche Therapieoptionen und prophylaktische Maßnahmen bei Sensibilitätsstörungen nach einer Wurzelkanalbehandlung im Molarenbereich diskutiert

Künstliche Intelligenz in der oralen Chirurgie und Medizin

Das Forschungsgebiet der künstlichen Intelligenz (KI) ist endgültig in der öffentlichen Wahrnehmung angekommen. Durch die Zusammenarbeit zwischen Informatik und Zahnmedizin wird ein großer Erkenntnisgewinn erwartet. Besonderes Potenzial besteht in der Vernetzung von allgemein- mit zahnmedizinischen Daten. Hierdurch können neue Einblicke in die Relevanz der oralen Gesundheit für den Gesamtorganismus gewonnen werden. Weitere interessante Forschungsfelder für KI in der Chirurgie entstehen für die radiologische und fotografische Bildgebung sowie die Diagnostik. In diesem Beitrag wird aufgezeigt, wie auf Basis von maschinellem Lernen („Machine learning“) klinische Gebiete wie z. B. die Diagnostik prämaligner und maligner Läsionen, die Diagnostik Medikamenten-assoziierter Kiefernekrosen, die Planung implantologischer Eingriffe und das zahnärztliche Röntgen verändert werden. Klinisch eröffnen sich zahlreiche Chancen zum Erkenntnisgewinn bzw. zur Therapieverbesserung. All diese möglichen Verbesserungen erleichtern die Arbeit der Zahnärzte und verbessern die Therapiequalität für die Patienten. Um die Akzeptanz dieser Methoden bei den Ärzten, insbesondere aber auch bei den Patienten zu fördern, sollten die neuen digitalen Techniken transparente und rational erklärbare Diagnose- und Therapieergebnisse liefern

Detectability of Osseous Lesions with a Pre-Programmed Low-Dose Protocol for Cone-Beam Computed Tomography

The present study aimed to compare the diagnostic reliability of a pre-set, manufacturer-specific, low-dose mode against a standard-dose mode in the detection of four different osseous lesions in the mandible with cone-beam computed tomography (CBCT). Four types of lesions (periapical lesion, extended periodontal gap, recession of the buccal lamella, sequestrum/fracture) were prepared on 40 pig mandibles. CBCT images were obtained from each mandible, with both the low-dose and standard-dose modes using the Orthophos SL CBCT device (Dentsply-Sirona, Bensheim, Germany). Twelve assessors quantitatively (detection of lesions) and qualitatively (assessment of detectability) evaluated the CBCT images in SIDEXIS 4 (Dentsply-Sirona) using a study-specific digital examination tool. A correct diagnosis was achieved in almost 71% (LD: 70.8%; SD: 70.9%) of 1920 lesions, without a statistically significant difference between the low-dose and standard-dose mode. This finding was consistent across all four lesion types. In conclusion, while low-dose mode and standard-dose mode CBCT scans performed similarly in the detection of four prepared lesions of the mandible, the former may be a promising, user-friendly alternative method of obtaining radiation-optimized, three-dimensional images in accordance with the As Low As Diagnostically Acceptable (ALADA) principle