Evaluation of masticatory efficiency and OHRQoL in implant-retained overdenture with different numbers of implant in the edentulous mandible: a one-year follow-up prospective study.

PURPOSE: The aim of this article is to evaluate to the masticatory function performance and Oral Health-related Quality of Life (OHRQoL) in implant-retained overdenture compared with different implant number placements in the edentulous mandible. METHODS: From 2013 to 2015, each patients received 3 implants (iSy-Implant, Camlog, Wimsheim, Germany) in intraforaminal mandible (34, 41/31, 44). After operation, inserted implants were gradually loaded and incorporated into an overdenture with a self-aligning attachment system (Locator abutments) in 3 + 3 + 3 months. Five checked points were performed chewing cycle test with multicolored chewing gum and OHIP-G14 questionnaire and a sum score questionnaire as following: pre-operation, one implant load (41/31), two implants loaded (33,43), three implants loaded and 1-year follow up. RESULT: A total of 10 patients with 30 implants were placed, the survival rate of the implants was 100% within 1-year follow-up. Regarding the masticatory function analysis, for the higher number of chewing cycles, the higher mixing rate was observed. After 1 year, the inter-mixing rate without significant changes was found compared to the time after three implants were loaded with attachment system. The mean value of OHIP-G14 was 30.4 preoperatively, 21.1 after loading the first locator, 10.7 after loading two locator abutments, and 3.2 after loading all three locator abutments. After 1 year, OHIP-G14 was 2.6 without significantly changed. The mean of the sum score was 15.5 preoperatively, 27.8 after activation of the first locator, 39.4 after activation of two locators, 46.2 after activation of all three locators, and 47.3 after 1 year. An increase of 0.7 sum score units per time point was observed. No significance was detectable, analogous to OHIP-G14, compared to the time of activation of all three locator setups (p-value = 0.22). CONCLUSIONS: A significant improvement in masticatory function performance and OHRQoL was evaluated with the increasing number of implants with locator attachment in edentulous mandible. With the investigation of the OHIP-G14 and sum score, the results of patient report outcome might be associated with the increase in the number of implants.

Platelet-rich fibrin for rehydration and pre-vascularization of an acellular, collagen membrane of porcine origin.

OBJECTIVES: Pre-vascularization of the collagen membranes with autologous platelet concentrates is a standard procedure in oral and maxillofacial surgery. This study analyzed the possible interaction of an acellular collagen membrane of porcine origin (NM) with platelet-rich fibrin (PRF) regarding its rehydration protocol with differences in pH values and effect on angiogenesis. MATERIALS AND METHODS: NM was analyzed alone and combined with solid PRF by plotting or co-culturing with injectable PRF. Different media (venous blood, buffer solution with a fixed pH value of 7, saline solution, and injectable PRF) were used to analyze the influence on pH value during rehydration. Chorion allantois membrane assay (CAM) was applied to check pro-angiogenic effects after 24, 48, and 72 h, followed by immunohistochemical analysis. RESULTS: Rehydration in injectable PRF showed acidity over time (p < 0.05). A definite pro-angiogenic effect of NM alone was found regarding neo-vessel formation supported by the respective light microscopically analysis without significant differences to PRF alone (p > 0.005). This pro-angiogenic effect could not be exaggerated when NM was combined with liquid/solid PRF (each p > 0.005). CONCLUSIONS: Rehydration with liquid PRF of the collagen membrane results in acidity compared to a saline solution or patient's blood. The significant pro-angiogenic potential of the membrane alone resulted in enhanced neo-vessel formation that could not be optimized with the addition of PRF. CLINICAL RELEVANCE STATEMENT: Using injectable PRF for rehydration protocol of the collagen membrane leads to acidosis that can ultimately optimize wound healing. Differences in the physio-mechanical interplay of collagen matrices and autologous platelet concentrates must result in clinical algorithms if pre-vascularization can maximize outcomes.

Influence of cold atmospheric-pressure-plasma in combination with different pretreatment methods on the pull-off tensile load in two-piece abutment-crowns: an in-vitro study.

BACKGROUND: In implant prosthetic dentistry, the adhesive connection of individualized ceramic crowns and prefabricated titanium bases leads to several benefits. However, the durability of the bonding could be a weak point and especially depends on sufficient surface pretreatment. Cold atmospheric-pressure plasma (CAP) is a pretreatment method that should improve the surface properties without physical damage. Thus, the purpose of this study was to investigate the influence of CAP treatment on pull-off tensile load in two-piece abutment crowns. METHODS: Eighty zirconia crowns and titanium bases were divided into eight groups (n = 10) according to their surface pretreatment prior to cementation with Panavia V5: no treatment (A); sandblasting (B); 10-MDP primer (C); sandblasting and primer (D); CAP (AP); sandblasting and CAP (BP); CAP and primer (CP); sandblasting, CAP and primer (DP). The specimens were thermocycled (5°/55°, 5000 cycles), and then the pull-off tensile load (TL) was measured. Statistical analyses were performed using three-way ANOVA with Tukey post-hoc and Fisher's exact tests. RESULTS: The results showed that the TL was highest in group D (p < 0.0001). Some combinations of different treatments led to effects that were greater than the sum of the individual effects. These effects were modified by interactions. Only in combination with primer, CAP treatment had a small but positive significant effect (group CP vs. C and CP vs. AP, p < 0.0001) which however did not come close to the strong interaction effect that resulted from the combination of sandblasting and primer. CONCLUSION: Within the limitations of this study, CAP treatment cannot be recommended in this specific field of indication due to its unreliable influence on TL in combination with other pretreatment methods.

Tumor Recurrence and Follow-Up Intervals in Oral Squamous Cell Carcinoma.

Tumor recurrence in oral squamous cell carcinoma (OSCC) is frequent. However, no consensus about follow-up interval is available. The aim of this study was to analyze the recurrence pattern, detection method and associated parameters for possible risk stratification. Histopathological and epidemiological features were obtained retrospectively and correlated with tumor recurrence and overall survival, distant and lymph node metastases. A total of 760 patients were included, of which 216 patients showed tumor recurrence (mean after 24 ± 26 months). Within the first 12 months, 24% of the recurrences were detected. The primary detection method was clinical examination (n = 123, 57%). Tumor recurrence significantly correlated with advanced histopathological grading (G2/3 vs. G1, p < 0.000) and lymph node metastasis (p = 0.004). Tumor recurrence was frequent. Clinical examination was the primary detection method and manifestation within the first 6−12 months was high. The degree of histopathological grading may be useful for risk stratification.

Short versus Standard Length Implants with Sinus Floor Elevation for the Atrophic Posterior Maxilla.

Objectives: the aim of this clinical study was to compare clinical and radiological outcomes of short dental implants inserted in pristine bone to standard length implants inserted in combination with sinus floor elevation. Materials and methods: For this clinical study, the clinical and radiological outcome of 126 short dental implants (84 patients), inserted in pristine bone were compared with 312 standard length implants (156 patients), placed in combination with maxillary sinus floor elevation procedures. Results: The short implant group (test group [TG]; mean follow-up (± standard deviation (SD) 56.6 ± 42.9 months) and the augmented group (control group [CG]; mean follow-up 41.6 ± 37.6 months) showed cumulative survival rates of 91.8% and 92.4%. Cumulative 5-year implant survival rates were 91.8% for the TG and 90.7% for the CG (p=0.421). Mean marginal bone loss was significantly higher in the CG than in the TG, with a mean MBL of 0.70 ± 0.72 mm in the TG and 0.96 ± 0.91 mm in the CG (p<0.001). A comparable and promising oral health-related quality of life (OHRQoL) was observed in the control and test groups. Conclusions: After over 3 years, short implants placed in the resorbed posterior maxilla obtained similar results to standard implants combined with maxillary sinus floor augmentation procedures.

Biomechanical Characterization of a New Acellular Dermal Matrix for Oral Soft Tissue Regeneration.

OBJECTIVES: Acellular dermal matrices (ADM) are a suitable alternative to autogenous soft tissue grafts (ASG). The aim of this study was to analyze the biomechanical properties and architectural features of ASG and ADM. MATERIALS AND METHODS: ASG were harvested from the hard palate of fresh frozen body donors as connective tissue grafts and compared to ADM of porcine origin (NovoMatrix, NM; mucoderm, MD). Maximum load (ML, Newton [N]) and expansion (E, [mm]) were measured after rehydration in saline solution by tensile strength measurement. Light microscopy (LM) and scanning electron microscopy (SEM) were performed to analyze the architectural features of ASG and ADM in high resolution. RESULTS: ASG demonstrated a significantly decreased ML compared to NM and MD (p < 0.0001 and p = 0.019). NM showed a significantly increased ML compared to MD (p = 0.001). ASG demonstrated a non-significantly reduced E compared to NM (p = 0.13) and a significantly increased E compared to MD (p = 0.025). NM showed an increased E compared to MD (p < 0.0001). LM and SEM highlighted the surface characteristics and internal structures of ASG and ADM, such as the surface compact layer of MD and the densely packed, parallel running and ordered collagen fibers of NM and MD. CONCLUSIONS: Significant differences concerning the biomechanical properties and architectural features of ASG, and ADM were found. CLINICAL RELEVANCE: Information about the biomechanical properties and architectural features of ASG and ADM can contribute to a better understanding of the clinical performance and extend the application area.

Customised products for orbital wall reconstruction: a systematic review.

The purpose of this systematic review was to critically analyse the recent literature and present the state of the art in customised reconstruction of orbital fractures. Three electronic databases and manual search approaches were used to identify relevant articles. Only controlled clinical studies were included. Primary outcome was defined as the status of recovery (complete/partial functional, and aesthetic disturbances). The benefit of intrasurgical navigation should be described. The secondary outcome was defined as the time of surgery, post-surgical events, and hospitalisation. Of the 552 records identified, eight met the inclusion criteria. Post-surgical results regarding recovery were superior in the customised group, and were comparable to the control group in five studies. The time of surgery was shorter in the customised groups, and liquid infusion and time of hospitalisation were reduced. Four studies documented more accurate reconstruction with the use of navigation. All the studies presented at least one bias, and considerable heterogeneity was evaluated. This review found that the use of customised meshes in combination with surgical navigation resulted in more accurate reconstruction. A significant reduction in surgical time was revealed.

The Efficiency of a Learning Software Compared to e-Books in Dental Education.

OBJECTIVES: Due to time-consuming curricular and extracurricular activities, students in dentistry and medicine can profit from efficient learning strategies. One strategy could be the preparation with individually designed educational software that embed different multimedia sources. The aim of this study was to determine the efficiency of such a program compared with an e-book similar to a traditional textbook. MATERIALS AND METHODS: Dentistry students of the Johannes Gutenberg-University of Mainz passed an entrance multiple-choice test on the topic of odontogenic tumors and were then randomized into two groups. Afterward, both groups had 14 days to study on the topic of odontogenic tumors either with a learning software or an e-book. A final exam was then taken and the two groups were compared. STATISTICAL ANALYSIS: A least significant difference post hoc analysis comparing the group average values was performed. The level of significance was p <0.05. RESULTS: Seventy-one students took part in the study. While students from the first and second clinical semester showed significantly better results and improvements with the e-book, an opposite effect was observed in students from the third and fifth clinical semester with significantly better results and improvements with the software. CONCLUSION: Depending on the clinical experience and knowledge, a multimedia educational software can help students in dentistry to enhance efficiency in the preparation for exams.

Oral Squamous Cell Carcinomas Developing from Oral Lichen Planus: A 5-21 year Retrospective Study.

Background and Aims: There is insufficient data regarding clinical characteristics, relapse rates, as well as lymph node metastasis of squamous cell carcinomas of the oral cavity (OSCC) developing from oral lichen planus (OLP-OSCC). The aim of this retrospective study was to evaluate clinical characteristics, as well as relapse, recurrence and survival rates of OLP-OSCC. Methods: In a retrospective monocenter analysis, all consecutive patients with an OSCC treated in the time period 1st January 2000-December 31 2016 were reviewed. All patients with OSCC developing from OLP/OLL (oral lichenoid lesions) were identified and analyzed for epidemiological data, risk profile, location of primary tumor, pTNM classification, lymph node metastasis, primary therapy, recurrence, and outcome. Results: A total of 103 patients (45%♂/ 55%♀) with an average age of 62 ± 14 year were included in this study. At the time of initial diagnosis, 17% (n = 18) of patients had cervical metastases (CM) whereas only 11% (11 patients) displayed advanced tumor sizes (T > 2). T-status (p = 0.003) and histopathological grading (p = 0.001) had an impact on the incidence of CM. 39.6% of the patients developed a relapse after an average of 24 months with a mean of two recurrences per patient. Advanced tumor size had a significant impact on the 5 year overall survival and was associated with disease-free survival of the patients (p < 0.001, respectively p = 0.004). Conclusion: Although initial lymph node metastases were not more frequent, more aggressive recurrence patterns compared to OSCC were seen for OLP-OSCC. Therefore, based on the study results, a modified recall for these patients is suggested.

Halitosis in Oral and Maxillofacial Surgery Patients - a Pilot Study.

BACKGROUND: Halitosis is a relatively inhomogeneous pathology with an extremely high prevalence in the population. Potential risk factors for bad breath include bacterial decomposition of organic material as well as numerous general and systemic diseases. The aim of the present study was to analyze whether certain subgroups of oral and maxillofacial surgery patients have a higher risk of halitosis. Further the impact of halitosis on the patient's quality of life was ascertained. METHODS: A total of 127 oral and maxillofacial patients aged between 19 and 86 years were enrolled in this study. On account of their underlining disease, patients were divided into five different investigation groups. The dental examination comprised tongue coating, periodontal screening index (PSI), gingival index (GI), PI (plaque index), DMF-T values as well as non-stimulated saliva flow rates. Halitosis was monitored both organoleptically according to Rosenberg and instrumentally by means of a Halimeter®, which records the volatile sulfur compounds (VSC values in ppm). Patients were further asked to fill out questionnaires regarding their medical history and oral hygiene, oral health (OHIP-14), and quality of life (BDI-II). RESULTS: Halitosis values, which were recorded by a Halimeter® correlated with the objective Rosenberg golden standard method. Furthermore, halitosis values correlated with elevated PSI, GI, and DMF-T values as well as the degree of tongue coating. Patients with oral cancer showed significantly higher VSC values compared to all other groups. No difference in VSC values could be found between all other patient groups. CONCLUSIONS: The Halimeter® could be validated as a suitable method for determining halitosis in oral and maxillofacial patients. The significantly increased halitosis values in cancer patients as opposed to all other patient groups suggests the potential of halitosis VSC values as a potential screening method. The development of non-invasive breath tests for diagnosis could be subject of future research.

The role of diabetes mellitus on the formation of severe odontogenic abscesses-a retrospective study.

OBJECTIVES: To analyze the correlation of diabetes mellitus and hyperglycemia with severe odontogenic abscesses. MATERIALS AND METHODS: Records of all patients in the Department of Oral and Maxillofacial Surgery of the Medical Center of the Johannes Gutenberg-University who underwent inpatient treatment for severe odontogenic abscesses between 2010 and 2016 were evaluated retrospectively regarding diabetes anamnesis, maximum and fasting blood sugar count, and duration until discharge. In order to compare the numbers to a general maxillofacial group, all patients who received inpatient treatment in 2013 for any diagnosis other than an abscess of the head and neck region were analyzed as well, and the numbers were correlated. RESULTS: In total, 977 abscess patients were found in the analyzed period. 7.0% of the patients had a known diagnosis of diabetes mellitus type II and 0.6% of type I. Correlation with the general group showed that abscesses were significantly more likely in diabetics as well as patients with abnormal maximum and fasting blood sugar counts. These patients also needed significantly longer inpatient treatment. CONCLUSIONS: Diabetics and patients with abnormal glucose tolerance show significantly higher numbers of severe odontogenic abscesses and might therefore benefit from earlier escalation of antibiotic medication. CLINICAL RELEVANCE: Severe odontogenic abscesses are one of the most frequent diagnoses in maxillofacial practice. Adjusting the therapeutic approach for diabetics or patients with abnormal blood sugar counts might help to prevent the development of abscesses.

Gender-Specific Differences of Dental Emergency Patients and the Use of Antibiotics: A 4-Year Retrospective Study.

PURPOSE: To evaluate the clinical characteristics of dental emergency patients with special regard on gender-specific differences related to the utilisation and use of antibiotics. MATERIALS AND METHODS: A retrospective analysis of all patients who presented to the emergency service of a university hospital in from 2010 to 2013 was performed. Demographic data, diagnosis, conducted treatment and the prescription of antibiotics were recorded and further analysed. RESULTS: Altogether, 16,296 patients visited the emergency service. Of these patients, only one-fourth (25.7%; n = 4185) suffered from a diagnosis with urgent treatment needs. Gender-specific differences were found in the reason of visit. Males presented significantly more often with severe diagnoses, like abscess or trauma. Females presented significantly more often with non-urgent diagnoses, not directly connected to oral hygiene habits, like temporomandibular disorders (TMD), denture sore or dolor post extractionem. Moreover, an overuse of antibiotics was found among emergency patients, with every fifth patient (20.2%; n = 3291) being prescribed an antibiotic. CONCLUSION: Better public education on dental emergencies and constant updates for dentists about the use of antibiotics in dental emergency care is necessary to secure adequate medical supply for severe dental emergencies and to avoid an inappropriate use of antibiotics.

Undergraduate Students' Acceptance of a Reciprocating One-File System for Endodontic Treatment.

OBJECTIVES: Reciprocating endodontic one-file systems are a comparatively new method for root canal shaping. Even though the mechanical properties are comparable to modern rotating mechanical systems, data about subjective assessment and application quality are scarce. This study evaluates the reciprocating one-file system in undergraduate education. MATERIALS AND METHODS: A total of 42 undergraduate students without experience regarding reciprocating file systems filled in a questionnaire in four different points in time (t 1-t 4) anonymously. The questionnaire was based on a numerical rating scale ranging from 0 to 10. STATISTICAL ANALYSIS: A least significant difference post-hoc analysis comparing the group average values was performed. The adjusted level of significance was p < 0.004 after Bonferroni correction. RESULTS: All rating scores increased after the first theoretical instruction. After the first practical training in artificial root canals in resin blocks and extracted teeth (t 2), the estimation of "time efficiency" (p = 0.002), "handling" (p < 0.001), and "overall impression" (p < 0.001) improved significantly. The "overall impression" remained constant and showed no significant changes after the first practical training. CONCLUSIONS: Reciprocating systems seem to show a good acceptance among first time users. Initial concerns about "work safety" decrease during every step of the educational process. Reciprocating one-file systems are a safe and well-accepted method in undergraduate teaching.

Sentinel lymph node biopsy in T1/T2 squamous cell carcinomas of the tongue: A prospective study.

Commonly used staging procedures often cannot predict the absence of cervical metastases (CM) in squamous cell carcinomas (SCCs) of the oral cavity. Due to the high incidence of occult CM in numerous N0 cases in the clinic, an elective neck dissection (ND) is performed. The sentinel lymph node biopsy (SNB) is a common concept in the modern surgical therapy of malignancies. The present study evaluates the applicability of this concept for T1/T2-SCC of the tongue. In a prospective clinical study, 10 consecutive patients with T1/T2-SCC of the tongue and cN0 necks, were enrolled. Following sentinel lymph node (SLN) scintigraphy, all patients underwent SNB with a γ-probe and a subsequent ND. SNB specimens were compared with histopathological assessments of surgical specimens from the ND. A total of 5 female and 5 male patients (mean age, 52 years; women, 62 years; men, 42 years), with a median follow-up time of 33.5 months (range, 10-40 months), were treated. All patients presented with detectable SLNs. In 7 cases, the SLN(s) and the residual ND were negative for CM. In 3 cases, the SLN(s) were positive without further CM in the other neck nodes. Furthermore, 1 patient showed additional CMs after 10 months in the contralateral neck and lung metastasis after 18 months, but none at the time of the initial treatment. The concept of an SNB appears to be applicable to the management of the cN0 neck in small SCC of the tongue. The role of SNB in the management of SCC requires further investigation by prospective trials with larger patient numbers.