Detection and measurements of apical lesions in the upper jaw by cone beam computed tomography and panoramic radiography as a function of cortical bone thickness Abstract Objectives In the current literature, cone beam computed tomography (CBCT) seems to be more accurate in detecting apical lesions (AL) than two-dimensional radiographs. Cortical bone thickness might have an influence on AL visibility. Therefore, the purpose of the study was to directly compare the diagnostic accuracy of panoramic radiography (PANO) and CBCT in detecting AL in the upper jaw and determine the influence of cortical bone thickness on AL visibility. Materials and methods Anonymised digital images of 351 patients who received a CBCT image and a panoramic radiograph within 90 days were examined for AL in the upper jaw. The analysis was conducted by a trained examiner and reviewed by an expert in dental radiology. Further, the dimensions of AL and cortical bone thickness in the region affected by AL were measured to determine their influence on visibility. Statistical analysis was carried out by means of statistical software (IBM SPSS 25; Armonk, NY, USA). Results The mean age of the patients was 58.9 years with an almost equal gender distribution. A total of 2223 teeth in the upper jaw were included in the final analysis. CBCT detected AL on 144 teeth (6.5%), of which only 23 were also visible on a PANO. The difference between both methods was significant (p < 0.001). The dimensions of AL measured within a PANO were approximately twice as high as those measured by CBCT. However, the difference was not significant (p ≥ 0.005). Cortical bone thickness had no influence on AL visibility. Conclusions and clinical relevance Panoramic radiographs are unsuitable for a reliable diagnosis of AL in the upper jaw, while CBCT leads to a better visualisation of AL. Bone thickness has no significant influence on AL visibility with either imaging method.

Visibility, location, and morphology of the primary maxillary sinus ostium and presence of accessory ostia: a retrospective analysis using cone beam computed tomography (CBCT) Abstract Objectives This retrospective study evaluated the visibility, location, and morphology of the primary maxillary ostium (PMO), as well as the presence and number of accessory maxillary ostia (AMO) in the maxillary sinus using cone beam computed tomography (CBCT). Materials and methods CBCT scans with a large field of view with both maxillary sinuses entirely visible, acquired from February 2016 to February 2018, were initially screened. Patients were included if there was no history of surgical intervention/trauma in the sinus region. Two observers evaluated the CBCTs for PMO and AMOs independently. PMO and AMOs were evaluated in axial, coronal, and sagittal CBCT views. In case of disagreement, a third observer served as a referee. The findings were correlated with age, gender, condition of the sinus mucosa, and status of the dentition to assess for potential influencing factors. Results A total of 184 patients (368 maxillary sinuses) were included. PMO was present and patent in 346 (94.0%) of the 368 analyzed sinuses. Most of the PMOs were located above the attachment of and in the middle third of the inferior turbinate (76.1%) and exhibited a slit shape (71.1%). An AMO was present in 167 (45.5%) of the 368 analyzed sinuses, and 66 (17.9%) sinuses had multiple AMOs. Gender and sinus mucosa morphology were found to be influencing factors for the patency of the PMO. Furthermore, gender seems to be influencing the presence of an AMO. Conclusions Most of the analyzed maxillary sinus cavities in the present population had a patent PMO. Being male and having morphological changes of the sinus mucosa were factors associated with a reduced prevalence of a patent PMO. Clinical relevance A maxillary sinus with pathological findings of the mucosa seems to have a reduced prevalence of patent PMOs. Therefore, clinicians should take care to assess any clinical and radiographical sign indicating a potential maxillary sinusitis prior to surgical interventions in this region, especially in cases with planned sinus floor elevation.

Influence of ultrasonic agitation on bond strength, marginal adaptation, and tooth discoloration provided by three coronary barrier endodontic materials Abstract Objectives The effect of ultrasonic agitation (UA) on bond strength and adaptation of cervical plugs prepared with MTA Angelus (MTA), MTA Repair HP (MTAHP), and Biodentine (BIO) was evaluated. Dentin discoloration caused by the materials/treatment was also assessed. Materials and methods Seventy-two single rooted teeth were divided into six groups depending on the materials/treatment. After cervical plug preparation, dentin discs were excised for the push-out test; additional discs were analyzed under the confocal microscope to determine adaptation (gaps occurrence). For dentin discoloration analysis (ΔE), blocks of bovine incisors had cavities prepared and filled with the materials/treatment (from 7 to 180 days). Results Both bond strength and adaptation were positively influenced by UA (P < 0.05). Comparison between materials showed an advantage for BIO when compared to MTAHP (P < 0.05). The best and worst results were provided by BIO/UA (12.66 MPa and 1.87%) and MTAHP (2.54 MPa and 28.58%), respectively. For ΔE, significant differences were observed throughout the periods. Just the MTA without UA exhibited noticeable discoloration at 180 days (P < 0.05). Conclusions UA favored a better adaptation of the materials to the dentin root, resulting in higher bond strength and adaptation of the materials to the root canal walls. Moreover, UA reduced MTA discoloration, keeping it imperceptible over the period evaluated. Clinical relevance The better adaptation and higher bond strength provided by UA can be considered clinically relevant due to the importance of maintaining blood clot integrity and the possible esthetic compromise provided by reparative materials when used as coronary barrier in regenerative procedures.

A metagenomic study of patients with alveolar osteitis after tooth extraction. A preliminary case-control study Abstract Objective To identify the microbiome in sockets with alveolar osteitis and compare it with a control group using metagenomic techniques. Materials and methods A case-control study was conducted in subjects that had undergone a tooth extraction. Microbiological samples were taken from the sockets of 10 patients with dry socket after tooth extraction (AO group) and 10 patients in whom exodontia resulted in no postoperative complications (control group). Bacterial DNA was isolated, and the 16S rRNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by Metagenomic Rapid Annotation. Results A total of 151 different species were found: 55 bacteria were only found in the AO group, 51 were specific to the control group, and 45 were common to both groups. The most frequently found genera in both groups were Prevotella. Prevotella nanceiensis, Actinomyces odontolyticus, Treponema maltophilum, Veillonella dispar, Tannerella forsythia, and Leuconostoc mesenteroides were found in several patients with alveolar osteitis, with an abundance greater than 0.5%, and were absent in all the control group samples. Conclusions Patients who develop alveolar osteitis after dental extractions might have a different microbiota from that of patients without postoperative complications. Since this is a preliminary report, further research is needed to assess whether bacteria play an important role in the etiology of dry socket. Clinical relevance This study seems to indicate that bacteria may play an important role in the alveolar osteitis etiology. Thus, new prevention and treatment strategies should be considered.

Identification of novel fibroblast-like cells from stem cells from human exfoliated deciduous teeth Abstract Objectives This study aimed to differentiate and characterize fibroblast-like cells from stem cells from human exfoliated deciduous teeth (SHED). Materials and methods The differentiation of fibroblast-like cells from SHED was carried out by using specific human recombinant connective tissue growth factor (CTGF). To characterize fibroblastic differentiation, the induced cells were subjected to morphological changes, proliferation rate, gene expression analysis using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), flow cytometry, and immunofluorescence staining. The commercial primary human gingival fibroblasts served as positive control in this study. Results The results from characterization analysis were compared with that of commercial cells to ensure that the cells differentiated from SHED were fibroblast-like cells. The results showed the inductive effect of CTGF for fibroblastic differentiation in SHED. SHED-derived fibroblasts were successfully characterized despite having similar morphological appearance, i.e., (i) significant proliferation rate between fibroblast-like cells and SHED, (ii) high expression of fibroblast-associated markers in qRT-PCR analysis, and (iii) positive staining against collagen type 1, fibroblast-specific protein 1, and human thymic fibroblasts in flow cytometry analysis and immunofluorescence staining. The same expression patterns were found in primary human gingival fibroblasts, respectively. SHED as negative control showed lower expression or no signal, thus confirming the cells differentiated from SHED were fibroblast-like cells. Conclusions Taken together, the protocol adopted in this study suggests CTGF to be an appropriate inducer in the differentiation of SHED into fibroblast-like cells. Clinical relevance The fibroblast-like cells differentiated from SHED could be used in future in vitro and in vivo dental tissue regeneration studies as well as in clinical applications where these cells are needed.

Comparison of Er,Cr:YSGG and diode laser effects on dentin hypersensitivity: a split-mouth randomized clinical trial Abstract Objectives The aim of the present study was to compare the clinical efficacy of diode laser and Er,Cr:YSGG lasers in the treatment of dentin hypersensitivity. Materials and methods Thirty-four teeth from 17 patients with dentin hypersensitivity were divided into two groups. In group D, the teeth were irradiated with diode laser beams with a wavelength of 940 nm for 1 min, and in group E, the teeth were irradiated with Er,Cr:YSGG laser beams with a wavelength of 2780 nm and a pulse width of 140–200 μs. Treatments with laser beams were carried out in 1 session. Sensitivity was assessed with air spray and a dental explorer. Pain severity was measured with the use of visual analog scale (VAS) before and after laser application. Results A decrease in dentin hypersensitivity was observed in both groups immediately, 1 week, and 1 month after laser irradiation. Statistically significant differences were found between the two groups in dentin hypersensitivity severity only 1 month after laser application. The decrease in dentin hypersensitivity by Er,Cr:YSGG laser was significantly higher than that by diode laser at this time interval. Conclusion The decrease in dentin hypersensitivity after application of Er,Cr:YSGG laser was significantly higher than that after the application of diode laser at 1-month postoperative interval. Clinical relevance Er,Cr:YSGG laser is a better choice than diode laser for the treatment of dentin hypersensitivity in the short term.

Impact of type of tooth on outcome of non-surgical root canal treatment Abstract Objectives We assessed the impact of type of tooth on the outcome of root canal treatment (RCT) according to factors potentially weakening the prognosis such as preoperative apical periodontitis (AP) and treatment modality (primary or secondary RCT). Materials and methods We scrutinized patient documents including pre- and postoperative radiographs of 640 permanent teeth receiving non-surgical RCT at Helsinki University Clinic in 2008–2011. Of teeth, 44% were molars, 32% premolars, and 24% anterior teeth. Patients’ mean age was 51.5 years; 51% were male. AP was present in 60.5% of teeth preoperatively. We used the periapical index (PAI) to assess the radiographs and defined radiographically “healthy” and “healing” cases as successful. Statistical evaluation included chi-squared tests, Fisher’s exact tests, t tests, and logistic regression modeling. Results The overall success rate (SR) was 84.1%; 88.3% for primary and 75.5% for secondary RCT (p < 0.001). The SRs for anterior teeth, premolars and molars were 85.6%, 88.8%, and 79.7%, respectively. Teeth with and without AP had SRs of 77.3% and 94.5%, respectively (p < 0.001). The RCTs were more likely to succeed in anterior teeth and premolars than in molars (OR 1.7; 95% CI 1.1–2.7) and in females than in males (OR 1.9; 95% CI 1.2–3.1). Conclusions Apart from existing AP and retreatment scenario, also, the type of tooth and gender had a significant influence on the outcome of RCT in this study. Clinical relevance The prognosis of RCT varies by type of tooth; special attention should be given to RCT of molar teeth.

Relationship between periodontal inflammation and calcium channel blockers induced gingival overgrowth—a cross-sectional study in a Japanese population Abstract Objectives Periodontal inflammation is regarded as a risk factor for drug-induced gingival overgrowth (DIGO). In order to elucidate the involvement of periodontal inflammation in DIGO, the periodontal status of subjects who do not develop DIGO despite receiving causative drugs (non-responders) needs to be examined. Therefore, the aim of the present study which was a pilot study was to assess periodontal inflammatory variables in responders (calcium channel blocker induced-GO patients), non-responders, and patients who did not receive causative drugs (non-consumers). Materials and methods The following parameters were measured: (1) existence of gingival overgrowth, (2) number of teeth, (3) mean periodontal pocket depth (PPD), and (4) percentage of positive sites for bleeding on probing (BOP). The periodontal inflamed surface area (PISA) and periodontal epithelial surface area (PESA) and the PISA/PESA ratio which indicated the degree of periodontal inflammation in each patient were also used to evaluate periodontal inflammation. Results Thirteen responders, 32 non-responders, and 83 non-consumers were included in the analyses. The mean PPD, percentage of BOP, PESA, and PISA, and the PISA/PESA ratio were significantly higher in responders than in non-responders and non-consumers (p < 0.01). The BOP, PISA, and PISA/PESA ratio were significantly lower in non-responders than in non-consumers (p < 0.05). A positive correlation was found between PPD and age in non-consumers. On the other hand, a negative correlation was noted between PPD and age in non-responders. Conclusions Periodontal inflammation may be associated with the initiation of DIGO. Clinical relevance It could be speculated that periodontal therapy before the administration of calcium channel blockers may prevent the development of gingival overgrowth.

Removal of stones from the superficial lobe of the submandibular gland (SMG) via an intraoral endoscopy-assisted sialolithotomy Abstract Objectives Sialolithiasis is the most common cause of chronic sialadenitis of the submandibular gland (SMG). Symptomatic superficial lobe stones are often treated by submandibulectomy. A gland preserving operation allows for transoral stone removal through endoscopically assisted sialolithotomy. Herein, we provide clinical and sonographical follow-up data in patients who underwent sialolithotomy under general anesthesia. Materials and methods Sixty patients treated at the Department of Oral and Maxillofacial Surgery at Düsseldorf University Hospital for superficial lobe sialolithiasis of SMG were included in this study. All received transoral sialolithotomy under general anesthesia. Follow-up was conducted via standardized patient questionnaires, clinical examination, and B-mode and color Doppler sonography. Results Mean patient age was 48.9 years. 56.6% of right and 43.4% of left SMG were affected. Mean follow-up was 45 months. Fifty-five of 59 detected stones could be removed. Mean operation time was 71 min. 3.3% of patients reported recurrent episodes of postoperative pain and 10% felt recurrent episodes of gland swelling. Persistent postoperative lingual nerve hypesthesia was described in one patient. No facial nerve damages occurred. Salivary flow rates remained reduced in most of the affected glands upon stone removal. Sonographical follow-up data of the previously affected SMG after intraoral endoscopy-assisted sialolithotomy showed a regular gland size in 70.8% of cases, a parenchyma free of inflammation in 93.8%, and without signs of fibrosis in 72.9% of cases. 68.7% of patients showed a regular structure of Wharton’s duct at time of follow-up. In total, 89.6% of patients were diagnosed stone-free within both glands on follow-up. No case required subsequent submandibulectomy. Conclusions Sialolithotomy of Wharton’s duct for removal of stones from the SMG’s superficial lobe is a promising alternative to submandibulectomy. Clinical relevance Reduction of postoperative morbidity through endoscopically assisted sialolithotomy for removal of superficial lobe stones from SMG. Trial registration Ethics Committee of Heinrich-Heine-University Düsseldorf (no. 5586)

Different surface modifications combined with universal adhesives: the impact on the bonding properties of zirconia to composite resin cement Abstract Objective The purpose of this study was to analyze the impact of plasma treatment and (universal adhesives) UAs on the bonding properties of zirconia. Material and methods Zirconia specimens (N = 744; n = 186/pretreatment) were prepared, highly polished, and pretreated: (i) plasma (oxygen plasma, 10s, 5 mm), (ii) airborne-particle abrasion (alumina, 50 μm, 0.05 MPa, 5 s, 10 mm), (iii) airborne-particle abrasion + plasma, and (iv) without pretreatment (highly polished surface). Surface roughness (Ra) and surface free energy (SFE) were measured (n = 6/pretreatment). Tensile bond strength (TBS) specimens (n = 180/pretreatment) were further divided (n = 18/conditioning): Clearfil Ceramic Primer (PCG), All-Bond Universal (ABU), Adhese Universal (AU), Clearfil Universal Bond (CUB), G-Premio Bond (GPB), Futurabond U (FBU), iBond Universal (IBU), One Coat 7 Universal (OCU), Scotchbond Universal (SBU), and no conditioning. PCG was luted with Panavia F2.0 and the remaining groups with DuoCem. After storage in distilled water (24 h; 37 °C) and thermocycling (5000×; 5 °C/55 °C), TBS was measured and fracture types (FTs) were determined. Data were analyzed using univariate ANOVA with a partial eta square (ƞP2), the Kruskal–Wallis H, the Mann–Whitney U, and the Chi2 test (P < .05). Results Plasma treatment resulted in an increase of SFE but had no impact on Ra. Airborne-particle abrasion resulted in the highest Ra and a higher TBS when compared with plasma and non-treatment. SBU and AU obtained a higher TBS when compared with PCG. OCU, FBU, ABU, IBU, and GPB indicated comparable TBS to PCG. CUB revealed the lowest TBS. Conclusions Plasma treatment cannot substitute airborne-particle abrasion when bonding zirconia but MDP-containing adhesives are essential for successful clinical outcomes. Clinical relevance Airborne-particle abrasion with a low pressure (0.05 MPa) in combination with UAs promotes the clinical success of adhesively bonded zirconia restorations.