The effect of polyethylenglycol gel on the delivery and osteogenic differentiation of homologous tooth germ-derived stem cells in a porcine model.

OBJECTIVES: The aim of this study was to investigate if bone regeneration can be promoted by homologous transplantation of STRO-1 sorted (STRO-1+) porcine tooth germ mesenchymal stem cells (TGSCs) with the combination of polyethylenglycol (PEG)-based hydrogel and biphasic calcium phosphate (BCP) scaffolds. MATERIAL AND METHODS: TGSCs were isolated from impacted third molars of domestic pigs. Nine critical-sized defects were created as (1) untreated defect; filled with (2) autogenous bone; (3) BCP + PEG; (4) BCP + PEG + unsorted TGSCs; (5) BCP + unsorted TGSCs; (6) BCP + PEG + STRO-1-sorted TGSCs; (7) BCP + STRO-1-sorted TGSCs; (8) BCP + PEG + osteogenic induced unsorted TGSCs; and (9) BCP + PEG + osteogenic induced STRO-1-sorted TGSCs in 20 domestic pigs. CM-DiI labelling was used to track cells in vivo. Histomorphometric assessment of new bone formation was achieved by toluidine blue O staining and microradiography after 1, 2, 4 and 12 weeks posttransplantation. RESULTS: Complete healing was achieved in all defects although defects with PEG hydrogel presented better bone formation while STRO-1+ and unsorted TGSCs showed similar ability to form new bone after 12 weeks. Transplanted cells were seen in defects where PEG hydrogel was used as carriers in contrast to defects treated with cells and only bone grafts. CONCLUSIONS: PEG hydrogel is an efficient carrier for homologous stem cell transplantation. TGSCs are capable of promoting bone healing in critical-sized defects in combination with bone graft and PEG hydrogel. CLINICAL RELEVANCE: This study provides information about the importance of the delivery vehicle for future translational stem cell delivery approaches.

Correction to: Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin-a retrospective study.

The following note was inadvertently omitted from the published paper: This work was performed in (partial) fulfillment of the requirements for the first author's obtaining the degree Dr. med. dent.

Evaluation of Staff Satisfaction After Implementation of a Surgical Safety Checklist in the Ambulatory of an Oral and Maxillofacial Surgery Department and its Impact on Patient Safety.

PURPOSE: Safety checklists in medicine have been shown to be effective in the prevention of complications and adverse events in patients undergoing surgery. Such checklists are not as common in dentistry. The aims of this study were to propose a safety checklist for the ambulatory treatment of patients undergoing oral and implant surgery and to assess its impact on patient safety and staff satisfaction. MATERIALS AND METHODS: After implementation of a surgical safety checklist in the ambulatory treatment of patients undergoing oral and implant surgeries, a questionnaire regarding staff satisfaction and safety-related parameters was randomly administered. Incidents, complications, and adverse events were documented. Outcomes with (n = 40 surgeries) and without (n = 40 surgeries) use of the checklist were analyzed and compared. RESULTS: Staff reported high satisfaction with the use of the checklist, which demonstrably improved team communication and lowered stress levels during surgery. There was a statistically significantly higher frequency of reported incidents without the use of the checklist (n = 43) than with the use of the checklist (n = 10; P = .000). Most incidents were reported in the context of pre- and post-procedural processes. CONCLUSIONS: Safety checklists help to improve work processes, optimize communication, and lower stress levels. Their use in clinical dental practice is recommended.

Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin-a retrospective study.

OBJECTIVES: This study aimed to identify anatomical areas where resections of oral squamous cell carcinomas (OSCC) are significantly associated with close or positive margins. MATERIALS AND METHODS: This retrospective study included 330 patients with a primary OSCC from 2010 to 2015. Patient and tumour data were categorised into three groups by R-status (R0 [clear], ≥ 5 mm, 185 patients [56.06%]; R1 [positive], < 1 mm, 24 patients [7.27%]; and R0 [close], 1-5 mm, 121 patients [36.67%]). RESULTS: Areas where resections were significantly associated with close or positive margins were the hard palate (p < 0.001), buccal mucosa (p = 0.03), floor of the mouth (p = 0.004), lower alveolar ridge (p = 0.01), retromolar triangle (p = 0.005), and dorsal tongue (p = 0.02). CONCLUSIONS: Anatomical areas were identified in the oral cavity where it is challenging to resect OSCCs with an adequate safety margin. CLINICAL RELEVANCE: These results may enable surgeons to achieve a postulated safe distance during tumour resection, leading to a survival benefit for patients.

Development and validation of a classification and scoring system for the diagnosis of oral squamous cell carcinomas through confocal laser endomicroscopy.

BACKGROUND: Confocal laser endomicroscopy (CLE) is an optical biopsy method allowing in vivo microscopic imaging at 1000-fold magnification. It was the aim to evaluate CLE in the human oral cavity for the differentiation of physiological/carcinomatous mucosa and to establish and validate, for the first time, a scoring system to facilitate CLE assessment. METHODS: The study consisted of 4 phases: (1) CLE-imaging (in vivo) was performed after the intravenous injection of fluorescein in patients with histologically confirmed carcinomatous oral mucosa; (2) CLE-experts (n = 3) verified the applicability of CLE in the oral cavity for the differentiation between physiological and cancerous tissue compared to the gold standard of histopathological assessment; (3) based on specific patterns of tissue changes, CLE-experts (n = 3) developed a classification and scoring system (DOC-Score) to simplify the diagnosis of oral squamous cell carcinomas; (4) validation of the newly developed DOC-Score by non-CLE-experts (n = 3); final statistical evaluation of their classification performance (comparison to the results of CLE-experts and the histopathological analyses). RESULTS: Experts acquired and edited 45 sequences (260 s) of physiological and 50 sequences (518 s) of carcinomatous mucosa (total: 95 sequences/778 s). All sequences were evaluated independently by experts and non-experts (based on the newly proposed classification system). Sensitivity (0.953) and specificity (0.889) of the diagnoses by experts as well as sensitivity (0.973) and specificity (0.881) of the non-expert ratings correlated well with the results of the present gold standard of tissue histopathology. Experts had a positive predictive value (PPV) of 0.905 and a negative predictive value (NPV) of 0.945. Non-experts reached a PPV of 0.901 and a NPV of 0.967 with the help of the DOC-Score. Inter-rater reliability (Fleiss` kappa) was 0.73 for experts and 0.814 for non-experts. The intra-rater reliability (Cronbach's alpha) of the experts was 0.989 and 0.884 for non-experts. CONCLUSIONS: CLE is a suitable and valid method for experts to diagnose oral cancer. Using the DOC-Score system, an accurate chair-side diagnosis of oral cancer is feasible with comparable results to the gold standard of histopathology-even in daily clinical practice for non-experienced raters.

Competency in managing cardiac arrest: A scenario-based evaluation of dental students.

OBJECTIVE: Advanced Cardiovascular Life Support (ACLS) in life-threatening situations is perceived as a basic skill for dental professionals. However, medical emergency training in dental schools is often not standardized. The dental students' knowledge transfer to an ACLS setting thus remains questionable. The aim of the study was to evaluate dental pre-doctorate students' practical competence in ACLS in a standardized manner to enable the curriculum to be adapted to meet their particular needs. MATERIALS AND METHODS: Thirty dental students (age 25.47 ± 1.81; 16 male/14 female) in their last year of dental studies were randomly assigned to 15 teams. Students' ability to successfully manage ACLS was assessed by a scenario-based approach (training module: Laerdal® ALS Skillmaster). Competence was assessed by means of (a) an observation chart, (b) video analysis and (c) training module analysis (Laerdal HeartSim®4000; Version 1.4). The evaluation was conducted by a trained anesthesiologist with regard to the 2010 guidelines of the European Resuscitation Council (ERC). RESULTS: Only five teams (33.3%) checked for all three vital functions (response, breathing and circulation). All teams initiated cardiopulmonary resuscitation (CPR). Only 54.12% of the compressions performed during CPR were sufficient. Four teams stopped the CPR after initiation. In total, 93% of the teams used the equipment for bag-valve-mask ventilation and 53.3% used the AED (Automated external defibrillator). CONCLUSIONS: ACLS training on a regular basis is necessary and, consistent with a close link between dentistry and medicine, should be a standardized part of the medical emergency curriculum for dental students with a specific focus on the deficiencies revealed in this study.

Chronic recurrent multifocal osteomyelitis in association with pyoderma gangraenosum.

BACKGROUND: Chronic recurrent multifocal osteomyelitis (CRMO) is a rare acquired inflammatory skeletal disorder of unknown origin. CRMO was first described by Gideon in 1972 and mainly affects children and young adults of female gender. The CRMO is part of the clinical picture of non-bacterial Osteomyelitis (NBO) and typically presents a relapsing recurring course with both remission and spontaneous exacerbation. CRMO is typically encountered in the limbs and the metaphysis of long bones in particular. Usually the clinical symptoms include painful swellings of the affected regions. This case report describes the rare case of a CRMO of the mandible in association with pyoderma gangraenosum. CASE PRESENTATION: A 14-year old female caucasian patient, residing in the south of Germany, presented in the oncological outpatient clinic of our Department of Paediatrics and Adolescent Medicine in June 2014 complaining of increasing neck pain and progressive swelling at her left cheek ongoing for about 6 weeks. These symptoms had been occurring quarterly for 4 years, but had never been as pronounced. Blood biochemistry showed a moderately elevated CRP (35 mg/l) and a significantly increased blood sedimentation rate (BSR 48/120 mm). The panoramic radiograph, however, revealed a bone alteration in the left mandibular region. Further investigations confirmed the diagnosis of CRMO. CONCLUSION: The present case underlines the fact that rare diseases might occasionally present with even more rare symptoms. These occasions can obviously be considered to present a considerable diagnostic challenge.

Sinus floor augmentation with autogenous bone vs. a bovine-derived xenograft - a 5-year retrospective study.

OBJECTIVES: The long-term outcome after sinus augmentation with autogenous bone or a bovine xenograft (Bio-Oss(®)) was assessed in 47 patients. Inclusion criterion was a vertical dimension of the maxilla of <4 mm. After a functional loading period of 60 months, implant survival and reduction in the augmentation height were compared between the two groups evaluated. MATERIAL AND METHODS: Sinus augmentation was performed using mandibular bone grafts or Bio-Oss(®). In the autogenous bone group, 70 implants were placed in 23 patients, while in the Bio-Oss(®) group, 24 patients received 98 implants. Fisher's exact test and equivalence testing were used to compare implant survival rates. RESULTS: The overall survival rate of the implants was 95.8% 5 years after implant insertion. In the autogenous bone group, the implants had a survival rate of 97.1%, while in the Bio-Oss(®) group, 94.9% of the implants survived. The difference was not statistically significant (P > 0.05); both treatments are equivalent (confidence interval 90%) for the equivalence interval [-0.1; 0.1]. 43.5% of the cases showed no reduction in the augmentation height 5 years after implant insertion, when augmentation was performed with autogenous bone, while in the Bio-Oss(®) group, no resorption was found in 50% of the augmented areas. Up to 25% reduction in augmentation height was found in 47.8% in the autogenous and in 45.8% in the Bio-Oss(®) group. In 8.7% of all cases in the autogenous bone group and in 4.2 % in the Bio-Oss(®) group, up to 50% of the augmented height was resorbed. CONCLUSION: After a 5 years evaluation period, Bio-Oss(®) as material for the indication maxillary sinus augmentation shows to be equivalent to autogenous bone grafting.

Case report: Upper arm metastasis of an oral squamous cell carcinoma.

BACKGROUND: The Oral Squamous Cell Carcinoma (OSCC) frequently metastasizes lymphogenously. Haematogenous dissemination is less common. This report describes a rare case of a metastatic OSCC of the floor of the mouth to the patients' left upper arm. To our knowledge this is the first of such case described in the literature. CASE PRESENTATION: Twelve months after R0 tumor resection surgery, including microvascular reconstruction of the lower jaw followed by adjuvant radiotherapy, the patient was admitted for osteosynthesis plates removal. During clinical examination a tumor located at his left upper arm was detected. According to the patient the tumor has demonstrated rapid growth. Macroscopic appearance and conventional imaging led to the differential diagnosis of an abscess. MR-imaging could not differentiate between a tumor of soft tissue origin and a metastasis. A biopsy was taken and the pathological examination confirmed the diagnosis of an OSCC metastasis. The postoperative interdisciplinary tumor board recommended radiation therapy. CONCLUSION: Due to the fact that patients with regional lymph node metastases have a higher probability to develop distant metastasis a more detailed screening might be considered--especially when hemangiosis carcinomatosa was histologically or macroscopically found.

Long-term changes in graft height after maxillary sinus augmentation, onlay bone grafting, and combination of both techniques: a long-term retrospective cohort study.

OBJECTIVES: This investigation focused on long-term changes in graft height, implant survival rate, and peri-implant tissue conditions of dental implants placed in alveolar ridges after augmentation procedures with a follow-up of 10 years. MATERIAL AND METHODS: We conducted a retrospective cohort study with prospective long-term follow-up of 25 patients with edentulous severe atrophic maxillary situations who received a vertical augmentation procedure with autologous bone prior to implant placement. The participants were divided into three groups according to whether they underwent sinus elevation, onlay grafting, or a combination of both techniques. After a four-month healing period, 127 implants were inserted in the corresponding regions. Following a six-month healing period, the participants underwent prosthodontic rehabilitation, incorporating a fixed or removable implant denture. The cohort was clinically and radiographically followed up 1, 5, and 10 years after augmentation. The following parameters were measured: radiographic vertical bone changes, implant loss, peri-implant pocket depth (PD), width of keratinized mucosa (KM), sulcus fluid flow rate (SFFR), and the radiographic distance between the implant shoulder and the first visible bone-to-implant contact (DIB). RESULTS: Seven implants were lost during the observation period, resulting in a cumulative 10-year survival rate of 94.48%. Significant bone loss occurred during the first 12 months, after which the resorption slowed down and bone height eventually stabilized. After 10 years, the total vertical bone loss was 27.51% after onlay grafting, 28.14% after sinus elevation, and 30.24% in the combination group, with no statistically significant between-group differences. Peri-implant follow-up examinations revealed a positive correlation between SFFR and PD, respectively, DIB, and a negative correlation between SFFR and KM. CONCLUSION: The treatment method does not seem to impact vertical bone loss following augmentation using autologous grafts. This approach results in long-term stability of dental implants. A sufficient width of keratinized peri-implant mucosa is important to prevent peri-implant bone loss and inflammation.

The outcome after surgical therapy of bisphosphonate-associated osteonecrosis of the jaw--results of a clinical case series with an average follow-up of 20 months.

OBJECTIVES: The present case series evaluates the success rate of osteotomy and primary wound closure in patients with bisphosphonate-associated osteonecrosis of the jaw (BRONJ). MATERIALS AND METHODS: Eighty patients suffering from BRONJ were included in the study. All patients received intravenous bisphosphonate therapy and underwent osteotomy and primary wound closure according to a standardised protocol. After discharge, the patients were reviewed on a regular basis over an average time period of 20 months. RESULTS: During follow-up in 11 patients, a recurrence of BRONJ occurred in the former operation field. Seventeen patients died due to their underlying disease. The success rate of osteotomy and primary wound closure in the treatment of BRONJ was calculated at 84.2 % 20 months after surgery. The results showed non-significant difference concerning the outcome of surgery in the different clinical stages of BRONJ. CONCLUSIONS: In accordance with previous studies, stage-independent osteotomy and primary wound closure combined with antibiotics shall be deemed a viable treatment option in patients suffering from BRONJ. CLINICAL RELEVANCE: With a high success rate, osteotomy in combination with primary wound closure seems to be a viable alternative to more conservative protocols in the treatment of BRONJ.

Histological results after maxillary sinus augmentation with Straumann® BoneCeramic, Bio-Oss®, Puros®, and autologous bone. A randomized controlled clinical trial.

OBJECTIVE: This investigation focused on a comparison of clinical and histological characteristics after sinus floor augmentation with biphasic calcium phosphate (BCP, Straumann BoneCeramic(®) ), anorganic bovine bone (ABB, Geistlich Bio-Oss(®) ), mineralized cancellous bone allograft (MCBA, Zimmer Puros(®) ), or autologous bone (AB). MATERIALS AND METHODS: Thirty consecutive patients with a posterior edentulous maxillary situation and a vertical bone height less than or equal to 4 mm were included in this study. A two-stage procedure was carried out. After augmentation of the maxillary sinus with ABB, BCP, MCBA, or AB followed by a healing period of 5 months, biopsies were taken with simultaneous implant placement. The samples were analyzed using microradiography and histology. RESULTS: Ninety-four implants were placed in the augmented positions and 53 bone biopsies were taken and evaluated. The bone volume fraction of newly formed bone was measured as 30.28 ± 2.16% for BCP, 24.9 ± 5.67% for ABB, 41.74 ± 2.1% for AB, and 35.41 ± 2.78% for MCBA with significant increases in bone volume of AB vs. BCP and ABB, and MCBA vs. ABB samples. Significantly different residual bone substitute material was measured as 15.8 ± 2.1% in the BCP group and 21.36 ± 4.83% in the ABB group. CONCLUSION: As it provides the highest rate of de novo bone formation, AB can be considered to remain the gold standard in sinus floor augmentation. All tested control materials showed comparable results and are suitable for maxillary sinus augmentation.

The diameter of anodic TiO2 nanotubes affects bone formation and correlates with the bone morphogenetic protein-2 expression in vivo.

INTRODUCTION: Recently, it has been demonstrated that the nanoscale environment is a critical factor for cellular behaviour. It has been shown that the diameter of TiO2 nanotube layers controls the cellular behaviour of cells involved in the bone-forming process in vitro. Therefore, the aim of the present study was to investigate the effects of the diameter of TiO2 nanotubes on peri-implant bone formation and the expression of bone matrix proteins in vivo. MATERIALS AND METHODS: Ninety experimental implants with a nanotube diameter ranging from 15 up to 100 nm were placed in the frontal skulls of six domestic pigs, whereas untreated implants served as controls. The bone-implant contact (BIC) as well as the expression of bone morphogenetic protein (BMP)-2, collagen type-I and osteocalcin were histomorphometrically and immunohistochemically analysed after 30 days. RESULTS: Evaluating the BIC, a significant higher value, could be found for the 50, 70 and 100 nm groups compared with the controls, whereas a correlation with the BMP-2 expression was present. The BMP-2 expression within the 50, 70 and 100 nm groups was statistically different compared with the control group. Significant difference was found for the osteocalcin expression in the 70 nm group. No statistical difference was found evaluating collagen type-I. SEM evaluation of the specimen surfaces revealed that the nanotube coatings do resist shearing forces evoked by implant insertion. CONCLUSION: The nanotube diameter can be designed to support cellular functions of osteoblasts and osteoclasts in vivo, including differentiation and protein expression and therefore offer a powerful tool for the controlled formation of peri-implant bone around medical implant devices.

Diabetes mellitus negatively affects peri-implant bone formation in the diabetic domestic pig.

AIM: Diabetes mellitus is classified as a relative contraindication for implant treatment, and higher failure rates have been seen in diabetic patients. The aim of the present study was to investigate the effect of diabetes on peri-implant bone formation in an animal model of human bone repair. MATERIALS AND METHODS: Diabetes was induced by an intra-venous application of streptozotocin (90 mg/kg) in 15 domestic pigs. Implants were placed after significant histopathological changes in the hard and soft tissues were verified. The bone-implant contact (BIC), peri-implant bone mineral density (BMD), and expression of collagen type-I and osteocalcin proteins were qualitatively evaluated 4 and 12 weeks after implantation. Fifteen animals served as healthy controls. RESULTS: Diabetes caused pathological changes in the soft and hard tissues. The BIC and BMD were significantly reduced in the diabetic group after 4 and 12 weeks. Collagen type-I was increased in the diabetic group at both time points, whereas osteocalcin was reduced in the diabetic group. CONCLUSIONS: Poorly controlled diabetes negatively affects peri-implant bone formation and bone mineralization. These findings have to be taken into consideration for diabetic patients with an indication for implant therapy.

Automatic quantification of speech intelligibility in patients after treatment for oral squamous cell carcinoma.

PURPOSE: Treatment of oral carcinomas often causes reduced speech intelligibility. It was the aim of this study to objectively evaluate the speech intelligibility of patients after multimodal therapy for oral squamous cell carcinoma (OSCC) with a computer-based, automatic speech recognition system. MATERIALS AND METHODS: The speech intelligibility of 59 patients after multimodal tumor treatment for OSCC, located at the lateral tongue, floor of the mouth, or the alveolar crest of the lower jaw, was objectively analyzed by a computer-based speech recognition system that calculates the percentage of correct word recognition (WR). RESULTS: The patients' WR was significantly reduced compared with a healthy control group without speech impairment (P ≤ .001). Higher T-classification was associated with a reduced WR (P < .01). Tumors located at the tongue showed a significantly higher WR than tumors at the floor of the mouth or the alveolar crest (P ≤ .001). Surgical resection and reconstruction of the lower jaw bone significantly reduced the WR (P ≤ .001) compared with cases without osseous tumor infiltration. CONCLUSIONS: Speech intelligibility after treatment for OSCC, objectively quantified by a standardized automatic speech recognition system, is reduced for increasing tumor size, increasing resection volume, and tumor localization near the lower jaw. Surgical reconstruction techniques seem to have an impact on speech intelligibility.

Validation of optical three-dimensional plagiocephalometry by computed tomography, direct measurement, and indirect measurements using thermoplastic bands.

The aim of the study was to validate optical three-dimensional surface imaging for plagiocephalometry by comparing it with established direct and indirect plagiocephalometric measurements. From head models with symmetric and asymmetric shapes, a number of distances were determined for plagiocephalometry. Data were acquired by optical three-dimensional surface imaging, direct and indirect measurements, and computed tomography. Data acquisition was repeated 10 times with each method. In 10 patients with positional plagiocephaly, optical three-dimensional surface data were acquired, and thermoplastic strips were used to reproduce the largest circumferences of the patients' heads. All measurements were carried out by the same observer. The measurements for the head models were used to assess the reproducibility of the different measurement techniques and to check if there were statistically significant differences between them. The patient measurements were also used to determine if there were statistically significant differences between the different techniques in clinical use. None of the plagiocephalometric distances showed statistically significant differences when the 4 different methods were compared on the head models (P > 0.05). Comparison of plagiocephalometric distances obtained from optical three-dimensional imaging and from thermoplastic strips in clinical use showed also no significant difference (P > 0.05). The results of the current study reveal that optical three-dimensional imaging is a relevant alternative to other established techniques in plagiocephalometry that should be tested in larger patient series.

Osteotomy and primary wound closure in bisphosphonate-associated osteonecrosis of the jaw: a prospective clinical study with 12 months follow-up.

GOALS OF WORK: This is a prospective clinical study aimed at assessing the success rate of osteotomy and primary wound closure in patients with bisphosphonate-associated osteonecrosis of the jaw (BONJ). MATERIALS AND METHODS: Fifty patients who had received bisphosphonates intravenously and subsequently suffered from BONJ were included in the study. All patients underwent osteotomy of the affected jaw bone region and primary wound closure under general anaesthesia. They were followed up bimonthly for a period of 12 months. RESULTS: Macroscopically altered bone could be completely removed in all cases. In two patients with plasmocytoma, major bleeding occurred postoperatively that required monitoring in an intensive care unit. In two cases, recurrence of BONJ was diagnosed during the first 2 months. In three patients, recurrence appeared between the fourth and the sixth month. In these cases, an additional osteotomy had to be performed. Six patients died during the follow-up period. In the remaining 39 patients, no signs of recurrence could be detected during the follow-up of 12 months. The success rate of the surviving patients was 89% after 1 year. CONCLUSION: Due to the high success rate of osteotomy and primary wound closure, it should be checked for every patient suffering from BONJ if osteotomy is a viable treatment option.

Panoramic radiograph, computed tomography or magnetic resonance imaging. Which imaging technique should be preferred in bisphosphonate-associated osteonecrosis of the jaw? A prospective clinical study.

It was the aim of the present study to find out which radiological imaging techniques allow assessing the extent of bisphosphonate-associated osteonecrosis of the jaw (BONJ) in an adequate way. Twenty-four patients suffering from BONJ were included in the study. Before surgery, each patient was examined with panoramic radiograph, contrast-enhanced magnetic resonance imaging (MRI) and non-enhanced computed tomography. The detectability of BONJ was assessed for the three imaging techniques. The extent of the jaw region affected by BONJ was determined in MRI and CT scans and compared to the intra-operative situation. The detectability of BONJ lesions was 54% for panoramic radiographs, 92% for MRI scans and 96% for computed tomography (CT) scans. The intra-operatively assessed extent of BONJ correlated significantly with the measurements on CT scans (p = 0.0004) but did not correlate significantly with the measurements in MRI scans (p = 0.241). The intra-operatively measured extent of BONJ differed significantly from the CT measurements (p = 0.00003) but not from the MRI data (p = 0.137). Although MRI as well as CT have a high detectability for BONJ lesions that exceeds that of panoramic radiographs by far, both techniques show problems with the exact assessment of the extent of BONJ lesions in the individual patients. Therefore, the relevance of MRI and CT for the preoperative assessment of the extent of BONJ lesions is limited. Future research should focus on the identification of imaging techniques that allow assessing the extent of BONJ lesions with a higher accuracy.

Long-Term Influence of Platelet-Rich Plasma (PRP) on Dental Implants after Maxillary Augmentation: Implant Survival and Success Rates.

The atrophic maxilla often requires bone augmentation before implant placement to ensure long-term implant success. A previous prospective clinical trial examined the use of platelet-rich plasma (PRP) during maxillary augmentation. The short-term results showed no positive effect of PRP. The aim of this study was to evaluate the same patient collective of the previous study regarding the PRP long-term impact on the survival and success of dental implants. Fifty-three patients from the previous study diagnosed with maxillary atrophy and augmented with autologous bone grafts from the iliac crest and dental implants, were included in this study. Treatment was carried out on both sides in 34 patients with a split-mouth-design in which one randomly chosen side was treated additionally with PRP, the other side was the control-side. Nineteen patients were treated only on one side and were assigned to the PRP-or the control group randomly. Implant follow-up of the patients from the previous study was performed after an average time of 13 years. Implant success was evaluated using two different success criteria. Thitry-seven patients (25 women and 12 men) were investigated in this study. Seventeen patients (12 female, 5 male) were included in the PRP group, while 20 patients (13 female, 7 male) participated in the control group. A total of 210 implants were inserted. Of these, 102 implants (48.57%) were placed in the PRP group and 108 implants (51.42%) in the control group. Out of 102 investigated implants in the PRP group, 6 were removed (survival rate 94.1%). While two of the 108 implants in the control group were loss (survival rate 98.1%). In the PRP group, the cumulative probability of survival after 15.1 years was 94.1% and in the control group, was 98.1%, with no significant difference between the two groups. Higher significant difference for the control group was found in the cumulative success probability using Albrektson criteria (p = 0.05). Positive impact of PRP on long-term implant survival and success could not be found.

Long-Term Influence of Platelet-Rich Plasma (PRP) on Dental Implants after Maxillary Augmentation: Retrospective Clinical and Radiological Outcomes of a Randomized Controlled Clinical Trial.

: The long-term clinical and radiological outcomes of dental implants inserted in augmented bone treated with platelet-rich plasma (PRP) has not been well addressed in the literature yet. This study is based on a collection of patients from a randomized controlled trial (RCT) that did not report any short-term positive effects of PRP on bone healing after sinus lift surgery using autologous iliac crest bone graft. This study aimed to evaluate the long-term impact of PRP regarding clinical and radiological outcomes on the inserted implants in the previous RCT. For this evaluation, we considered the following variables: plaque index, probing depth, bleeding index, mobility grade, Periotest® values, and radiological bone loss. Out of 53 patients (n = 306 implants) included in the previous study we were able to reinvestigate 37 patients (n = 210 implants) in two centers (31 in Giessen, Germany and 6 in Erlangen, Germany). Clinical and radiographic parameters suggested overall healthy conditions of the peri-implant tissue. The PRP-group and the control group did not differ significantly in the majority of the parameters. The overall evaluation showed that result data of the PRP-group was inferior to the control group in 64 percent of the evaluated parameters. The present study cannot provide evidence of a positive effect of PRP on the long-term implant clinical and radiological outcomes. In fact, a tendency towards inferior long-term results in the PRP-group was detected without reaching a significant threshold. Further controlled trials need to be conducted to investigate this correlation.