[Minimally invasive treatments and open joint surgery for disorders of the temporomandibular joint]. / Minimaal invasieve behandelingen en opengewrichtschirurgie voor aandoeningen van het kaakgewricht.

The initial treatment of symptomatic disorders of the temporomandibular joint typically consists of a conservative approach, in which medication (painkillers and muscle relaxants), orofacial physiotherapy and splints are most important. In most cases, minimally invasive treatment options, such as arthrocentesis, arthroscopy or joint injections, are only considered when conservative methods provide insufficient symptom reduction. There is, however, an ongoing debate about the optimal treatment strategy due to an increasing body of evidence concerning the superior effectiveness in symptom reduction of minimally invasive treatment options with regard to conservative treatments. If these minimally invasive treatment options are also ineffective, open joint surgery may be considered as a last option for a select group of patients.

Reliability and validity of handheld structured light scanners and a static stereophotogrammetry system in facial three-dimensional surface imaging.

Several new systems for three-dimensional (3D) surface imaging of the face have become available to assess changes following orthognathic or facial surgery. Before they can be implemented in practice, their reliability and validity must be established. Our aim, therefore, was to study the intra- and inter-system reliability and validity of 3dMD (stereophotogrammetry), Artec Eva and Artec Space Spider (both structured light scanners). Intra- and inter-system reliability, expressed in root mean square distance, was determined by scanning a mannequin's head and the faces of healthy volunteers multiple times. Validity was determined by comparing the linear measurements of the scans with the known distances of a 3D printed model. Post-processing errors were also calculated. Intra-system reliability after scanning the mannequin's head was best with the Artec Space Spider (0.04 mm Spider; 0.07 mm 3dMD; 0.08 mm Eva). The least difference in inter-system reliability after scanning the mannequin's head was between the Artec Space Spider and Artec Eva. The best intra-system reliability after scanning human subjects was with the Artec Space Spider (0.15 mm Spider; 0.20 mm Eva; 0.23 mm 3dMD). The least difference in inter-system reliability after scanning human subjects was between the Artec Eva and Artec Space Spider. The most accurate linear measurement validity occurred with the Artec Space Spider. The post-processing error was 0.01 mm for all the systems. The Artec Space Spider is the most reliable and valid scanning system.

Arthroscopy versus arthrocentesis and versus conservative treatments for temporomandibular joint disorders: a systematic review with meta-analysis and trial sequential analysis.

The aim of this systematic review was to assess the efficacy of arthroscopy compared to arthrocentesis and to conservative treatments for temporomandibular joint disorders. Thirteen controlled studies on various patient outcomes were included after a systematic search in seven electronic databases. Meta-analyses were conducted separately for arthroscopic surgery (AS) and arthroscopic lysis and lavage (ALL), and short-term (<6 months), intermediate-term (6 months to 5 years), and long-term (≥5 years) follow-up periods were considered. No significant differences in pain reduction and complication rates were found between AS or ALL and arthrocentesis. Regarding improvement in maximum mouth opening (MMO), both AS at intermediate-term and ALL at short-term follow-up were equally efficient when compared to arthrocentesis. However, at intermediate-term follow-up, ALL was superior to arthrocentesis for MMO improvement (mean difference 4.9 mm, 95% confidence interval 2.7-7.1 mm). Trial sequential analysis supported the conclusion of the meta-analysis for MMO improvement for ALL versus arthrocentesis studies at intermediate-term follow-up, but not for the other meta-analyses. Insufficient evidence exists to draw conclusions regarding other patient outcomes or about comparisons between arthroscopy and conservative treatments. Due to the low quality of the primary studies, further research is warranted before final conclusions can be drawn regarding the management of temporomandibular joint disorders.

Success rate of sialendoscopy. A systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review and meta-analysis on the efficacy and safety of sialendoscopy in the treatment of obstructive diseases of the major salivary glands. MATERIALS AND METHODS: We searched four databases for literature. The primary outcome assessed was the success rate. Secondary outcomes included the use of supportive devices, number of sialadenectomies and complications. Risk of bias was assessed. Meta-analyses with subgroup analysis were performed. RESULTS: In total, 91 studies were included, comprising 8218 patients undergoing 9043 sialendoscopic procedures. The majority of studies had a medium or high risk of bias. The incidence of sialadenectomy varied from 0% to 14%. No major complications were reported. Meta-analysis revealed a weighted pooled success rate of 80.9%. Subgroup analyses showed the weighted pooled success rate in patients with sialoliths (89.6%), stenoses (56.3%), submandibular glands (88.3%), parotid glands (81.2%), patients treated by an endoscopic-assisted transoral removal of a sialolith (86.3%), patients treated by a combined approach of the parotid gland (78.2%), patients with JRP (67.0%) and with RAIS (45.8%). CONCLUSION: The success rate of sialendoscopy did not considerably change in the last 9 years. Sialendoscopy is an efficient and safe procedure for the treatment of major salivary gland obstructive disease.

Arthrocentesis versus non-surgical intervention as initial treatment for temporomandibular joint arthralgia: a randomized controlled trial with long-term follow-up.

Arthrocentesis for arthralgia of the temporomandibular joint (TMJ) is often only indicated when conservative, non-surgical interventions have failed. However, performing arthrocentesis as initial therapy may facilitate earlier and better recuperation of the joint. The aim of this study was to assess the efficacy of this therapy with a long-term follow-up. Eighty-four patients were randomly allocated to receive either arthrocentesis as initial treatment (n = 41) or non-surgical intervention (n = 43). Pain (100-mm visual analogue scale, VAS) and mandibular function impairment questionnaire scores (MFIQ, 0-100) were recorded at 3, 12, and 26 weeks, and ≥ 5 years (median 6.2, interquartile range 5.6-7.4 years). Univariable analyses were performed and linear mixed-effect models were constructed. Patients in the arthrocentesis group experienced significantly lower TMJ arthralgia compared to those treated non-surgically (pain during movement: -10.23 mm (95% confidence interval -17.86; -2.60); pain at rest: - 8.39 mm (95% confidence interval -13.70; -3.08)), while mandibular function remained similar in the two groups (MFIQ -2.41 (95% confidence interval -8.61; 3.78)). Of the final sample, 10 patients (10/39, 26%) in the non-surgical intervention group and two patients (2/34, 6%) in the arthrocentesis group received additional treatment during follow-up. Thus, initial treatment with arthrocentesis reduced TMJ arthralgia more efficaciously than non-surgical intervention in the long term, while maintaining similar mandibular function.

Postoperative skeletal stability at the one-year follow-up after splintless Le Fort I osteotomy using patient-specific osteosynthesis versus conventional osteosynthesis: a randomized controlled trial.

The purpose of this study was to assess the 1-year skeletal stability of the osteotomized maxilla after Le Fort I surgery, comparing conventional osteosynthesis with patient-specific osteosynthesis. Patients were assigned to a conventional or patient-specific osteosynthesis group using prospective randomization. The primary outcome was the three-dimensional change in postoperative skeletal position of the maxilla between the 2-week and 1-year follow-up cone beam computed tomography scans. Fifty-eight patients completed the protocol for the 2-week postoperative analysis, and 27 patients completed the 1-year follow-up study protocol. Of the 27 patients completing the entire protocol, 13 were in the conventional group and 14 in the patient-specific osteosynthesis group. The three-dimensional translation analysis showed that the use of the patient-specific osteosynthesis resulted in a skeletally stable result, comparable to that of conventional miniplate fixation. For both the patient-specific osteosynthesis and conventional miniplate fixation groups, median translations of less than 1 mm and median rotations of less than 1° were observed, indicating that both methods of fixation resulted in a stable result for the 27 patients examined. For the Le Fort I osteotomy, the choice between patient-specific osteosynthesis and conventional osteosynthesis did not affect the postoperative skeletal stability after 1 year of follow-up.

ß-Adrenergic signaling induces Notch-mediated salivary gland progenitor cell control.

ß-Adrenergic signaling blockade is a mainstay of hypertension management. One percent of patients taking ß-blockers develop reduced salivary gland (SG) function. Here we investigate the role of SG progenitor cells in ß-blocker-induced hyposalivation, using human SG organoid cultures (SGOs). Compared with control SGs, initial low SG progenitor cell yield from patients taking ß-blockers was observed. When passaged, these SGOs recovered self-renewal and upregulated Notch pathway expression. Notch signaling was downregulated in situ in ß-adrenergic receptor-expressing luminal intercalated duct (ID) cells of patients taking ß-blockers. Control SGOs treated with ß-adrenergic agonist isoproterenol demonstrated increased proportion of luminal ID SGO cells with active Notch signaling. Control SGOs exposed to isoproterenol differentiated into more mature SGOs (mSGOs) expressing markers of acinar cells. We propose that ß-blocker-induced Notch signaling reduction in luminal ID cells hampers their ability to proliferate and differentiate into acinar cells, inducing a persistent hyposalivation in some patients taking ß-blocking medication.

Augmented Reality Visualization for Image-Guided Surgery: A Validation Study Using a Three-Dimensional Printed Phantom.

BACKGROUND: Oral and maxillofacial surgery currently relies on virtual surgery planning based on image data (CT, MRI). Three-dimensional (3D) visualizations are typically used to plan and predict the outcome of complex surgical procedures. To translate the virtual surgical plan to the operating room, it is either converted into physical 3D-printed guides or directly translated using real-time navigation systems. PURPOSE: This study aims to improve the translation of the virtual surgery plan to a surgical procedure, such as oncologic or trauma surgery, in terms of accuracy and speed. Here we report an augmented reality visualization technique for image-guided surgery. It describes how surgeons can visualize and interact with the virtual surgery plan and navigation data while in the operating room. The user friendliness and usability is objectified by a formal user study that compared our augmented reality assisted technique to the gold standard setup of a perioperative navigation system (Brainlab). Moreover, accuracy of typical navigation tasks as reaching landmarks and following trajectories is compared. RESULTS: Overall completion time of navigation tasks was 1.71 times faster using augmented reality (P = .034). Accuracy improved significantly using augmented reality (P < .001), for reaching physical landmarks a less strong correlation was found (P = .087). Although the participants were relatively unfamiliar with VR/AR (rated 2.25/5) and gesture-based interaction (rated 2/5), they reported that navigation tasks become easier to perform using augmented reality (difficulty Brainlab rated 3.25/5, HoloLens 2.4/5). CONCLUSION: The proposed workflow can be used in a wide range of image-guided surgery procedures as an addition to existing verified image guidance systems. Results of this user study imply that our technique enables typical navigation tasks to be performed faster and more accurately compared to the current gold standard. In addition, qualitative feedback on our augmented reality assisted technique was more positive compared to the standard setup.?>.

Accuracy of fit analysis of the patient-specific Groningen temporomandibular joint prosthesis.

Total joint replacement (TJR) with a prosthesis can be indicated for patients with severe temporomandibular joint (TMJ) dysfunction. Surgical accuracy is necessary for correct translation of the preoperatively predicted functional outcome, wear, and biomechanical behaviour of the patient-specific TMJ-TJR prosthesis. This study describes the first clinical applications of the patient-specific TMJ-TJR prosthesis according to the Groningen principles (G-TMJ-TJR), which was developed and validated in a prior human cadaver test study. The aim of this study was to validate the accuracy of placement of the patient-specific G-TMJ-TJR in the clinical setting. It was hypothesized that a virtual surgical plan (VSP) combined with guided placement of the patient-specific G-TMJ-TJR would be performed as predictably and accurately as in the prior cadaver series. All patients who received a VSP-based patient-specific G-TMJ-TJR between December 2017 and March 2020 were included in this study. The accuracy analysis was based on postoperative cone beam computed tomography (CBCT) data. All 11 prostheses could be inserted using routine pre-auricular and retromandibular surgical approaches. Analysis of the VSPs and postoperative CBCTs showed an average three-dimensional deviation of 1.07mm (standard deviation 0.46mm, range 0.33-1.91mm) for all of the fossa and mandibular components. The patient-specific G-TMJ-TJR can be applied predictably and accurately in a clinical setting.

[Development of MALT-lymphoma in Sjögren syndrome]. / Ontstaan van MALT-lymfomen bij het syndroom van Sjögren.

Important characteristics of Sjögren syndrome include a sensation of dry mouth, reduced saliva secretion and swelling of the large salivary glands, usually the parotids. Sjögren patients also run a significantly increased risk of developing a non-Hodgkin lymphoma, generally a so-called mucosa associated lymphoid tissue (MALT) lymphoma. Such a MALT lymphoma often develops in the parotid gland. In 2 cases patients presented with recurrent swellings of the parotid glands who developed both Sjögren syndrome and a MALT lymphoma in both of their parotid glands.

Splintless surgery using patient-specific osteosynthesis in Le Fort I osteotomies: a randomized controlled multi-centre trial.

The accuracy of orthognathic surgery has improved with three-dimensional virtual planning. The translation of the planning to the surgical result is reported to vary by >2mm. The aim of this randomized controlled multi-centre trial was to determine whether the use of splintless patient-specific osteosynthesis can improve the accuracy of maxillary translation. Patients requiring a Le Fort I osteotomy were included in the trial. The intervention group was treated using patient-specific osteosynthesis and the control group with conventional osteosynthesis and splint-based positioning. Fifty-eight patients completed the study protocol, 27 in the patient-specific osteosynthesis group and 31 in the control group. The per protocol median anteroposterior deviation was found to be 1.05mm (interquartile range (IQR) 0.45-2.72mm) in the patient-specific osteosynthesis group and 1.74mm (IQR 1.02-3.02mm) in the control group. The cranial-caudal deviation was 0.87mm (IQR 0.49-1.44mm) and 0.98mm (IQR 0.28-2.10mm), respectively, whereas the left-right translation deviation was 0.46mm (IQR 0.19-0.96mm) in the patient-specific osteosynthesis group and 1.07mm (IQR 0.62-1.55mm) in the control group. The splintless patient-specific osteosynthesis method improves the accuracy of maxillary translations in orthognathic surgery and is clinically relevant for planned anteroposterior translations of more than 3.70mm.

[Medicaments and oral healthcare. Mechanisms of interaction between medicaments]. / Serie: Medicamenten en mondzorg. Mechanismen van interacties van medicamenten.

Interactions between medicaments or between a medicament and another product used by the patient may result in a medicamentbecoming inactive or in an increase in the side effects. By proper historytaking, a dentist will often know which medicaments a patient uses and can take this into account in prescribing a medicament. Self-care medications and specific foods are often not spontaneously reported by a patient but can still interact with a medicament prescribed. A dentist should be aware of the interactions a prescribed medicament can have with other medicaments and products used by the patient. Therefore dentists have to ask directly about such medicaments and products, and record them in the patients' file.

Multi-modality 3D mandibular resection planning in head and neck cancer using CT and MRI data fusion: A clinical series.

OBJECTIVES: 3D virtual surgical planning (VSP) and guided surgery has been proven to be an effective tool for resection and reconstruction of the mandible. Currently, most widely used 3D VSP approaches to mandibular resection do not include detailed tumour information in the VSP. This manuscript presents a strategy where the aim was to incorporate tumour visualisation into the 3D virtual plan. Three-dimensional VSP of the mandibular resections was based on the fusion of CT and MRI data which was subsequently applied in clinical practice. METHODS: All patients diagnosed with oral squamous cell carcinoma between 2014 and 2017 at the University Medical Centre Groningen were included. The tumour was delineated on the MRI data, after which this dataset was fused with the CT bone data in order to construct a 3D bone and tumour model for virtual resection planning. Guided resections were performed and post-operative evaluation quantified the accuracy of the resection. The histopathological findings and patient and tumour characteristics were compared to those of a historical cohort (2009-2014) of conventional mandibular continuity resections. RESULTS: Twenty-four patients were included in the cohort. The average deviation from planned resection was found to be 2.2 mm. Histopathologic analysis confirmed all resection planes (bone) were tumour free, compared to 96.4% in the historic cohort. CONCLUSION: MRI-CT base tumour visualisation and 3D resection planning is a safe and accurate method for oncologic resection of the mandible. It is an improvement on the current methods reported for 3D resection planning based solely on CT data.

[Mandibular function after a condylectomy for unilateral condylar hyperplasia]. / Mandibulaire functie na condylectomie voor unilaterale condylaire hyperplasie.

Unilateral condylar hyperplasia is a rare growth disorder originating in the growth centre of the mandibular condyles and resulting in facial asymmetry. Primary treatment consists of condylectomy. In this cross-sectional research, limitations in mandibular function and oral health related quality of life were measured with the Mandibular Function Impairment Questionnaire and the Oral Health Impact Profile (NL49). The study included 17 patients who underwent treatment for unilateral condylar hyperplasia with a condylectomy in the University Medical Center Groningen between 1997 and 2012. The median (IQR) scores of the Mandibular Function Impairment Questionnaire (8,0 [1,0; 15,0]) and the Oral Health Impact Profile (25,0 [3,0; 53,0] were low compared to other conditions involving the mandible. A higher age was associated with increased limitations in mandibular function (rs = 0,588 (p = 0,013)). After a condylectomy for unilateral condylar hyperplasia the functional impairment of the mandible and the decrease in oral health related quality of life are low.

Development of a patient-specific temporomandibular joint prosthesis according to the Groningen principle through a cadaver test series.

OBJECTIVES: Patients suffering from osteoarthritis, ankylosis (e.g. post-trauma or tumour) in the temporomandibular joint (TMJ) can present with symptoms such as severely restricted mouth opening, pain or other dynamic restrictions of the mandible. To alleviate the symptoms, a total joint prosthesis can be indicated, such as the Groningen TMJ prosthesis. This was developed as a stock device with a lowered centre of rotation for improved translational and opening capacity. This study aimed to improve the design of the prosthesis, and produce a workflow for a customized Groningen TMJ prosthesis, in order to make it more accurate and predictable. METHODS: The fossa and mandibular components of the Groningen TMJ prosthesis were customized. A series of five human cadavers was operated and bilateral TMJ prostheses were placed using custom cutting and drilling guides. Placement accuracy was evaluated based on post-operative CT data. RESULTS: A total of N = 10 prostheses were placed and analysed. The average Euclidean distance deviation from planned to actual position was 0.81 mm (SD 0.21). All prostheses were placed according to the routine surgical approaches and had an excellent alignment with the bony structures. CONCLUSION: The newly developed custom Groningen TMJ prosthesis can be placed with great accuracy and is the first step for improving TMJ total joint replacement surgery.

Secondary surgical management of osteoradionecrosis using three-dimensional isodose curve visualization: a report of three cases.

Osteoradionecrosis is defined as bone death secondary to radiotherapy. There is a relationship between the radiation dose received and the occurrence of osteoradionecrosis of the jaws, with the risk increasing above a dose of 60Gy. In cases of class III mandibular osteoradionecrosis, a segmental resection can be indicated. Current practice is to completely remove the affected bone up to the point where the bone looks healthy and is bleeding. Exact resection planning and the use of guided surgery based on imaging of the bone changes have not been reported so far. This article describes a method whereby the radiotherapy dose information is incorporated into the imaging of the affected bone in order to plan a three-dimensional (3D) virtual guided resection and reconstruction of the mandible in osteoradionecrosis. The method enables 3D visualization of each desired dose field in relation to the 3D model of the affected bone. Two types of application - for resection and reconstruction - are described.

Measuring the social impact of dental research: An insight into the most influential articles on the Web.

OBJECTIVES: To identify the most discussed dental articles on the Web and to assess the association between the intensity of online attention, publication characteristics, and citations. MATERIALS AND METHODS: An Altmetric Explorer search was conducted for articles published in the 91 dental journals included in 2015 InCites™ Journal Citation Report® and mentioned online at all times. The 100 articles with the highest online attention, as measured by the "Altmetric Attention Score" (AAS), were screened for journal title, quartile of impact factor distribution (Q1-Q4), publication date, origin and affiliation of first author, article topic, type, and access. Citation counts were harvested from Scopus. RESULTS: The top 100 articles presented a median AAS of 119 and were mostly discussed on news outlets, Twitter, and Mendeley. Forty-one articles were published in Q1 journals, 24 in Q2 journals, 32 in Q3 journals, and three in Q4 journals. AAS was significantly higher in articles of Q2 journals (median AAS = 398, range = 70-513) than in articles of Q1. A weak reverse correlation existed between AAS and time since publication (r = -.25, p < .05). No correlation was detected between AAS and other publication characteristics or number of citations. CONCLUSIONS: Increased social impact of dental articles is not significantly associated with high citation rates.

[A PhD completed 9. The value of oral foci screening in oncology patients]. / Hora est 9. De waarde van tandheelkundig focusonderzoek bij oncologiepatiënten.

In both patients who undergo radiotherapy because of a tumour in the head and neck region and patients who are treated with high doses of chemotherapy because of haematological disorders, prior to treatment an oral foci screening is carried out. The aim of this focus investigation is to identify oral abnormalities, the so-called oral foci. Such foci can lead to oral problems during or post-treatment. A careful oral foci screening, conforming to protocol, appears to be very relevant for patients who have to undergo head and neck radiotherapy. Particular attention must be devoted to the evaluation of the perodontium, because the chance of disorders affecting the bone-healing that appear post-radiotherapy in the head and neck region is increased in patients with periodontitis. In patients with a haematological disorder, asymptomatic, chronic foci do not require treatment prior to or during the oncological treatment because such oral foci do not increase an extra risk of infectious complications, despite what was hitherto believed.

[Localised (juvenile) spongiotic hyperplasia of the gingiva; a less common laesion]. / Gelokaliseerde (juveniele) spongiotische hyperplasie van de gingiva: een minder bekende aandoening.

A 49-year-old woman presented with a superficial, ulcerative laesion of approximately 7x3 mm of the marginal labial gingiva of the first upper incisor right. The laesion had returned twice after limited surgical excision. On the basis of a new, extensive excisional biopsy, additional investigation was carried out by the pathologist, which led to a diagnosis of localised (juvenile) spongiotic gingival hyperplasia (LJSGH). The aetiology of LJSGH is still unclear. A typical characteristic is the localised and solitary presence of the laesion. Localised (juvenile) spongiotic hyperplasia of the gingiva is most often seen on the marginal labial gingiva of the maxilla. The laesion can disappear spontaneously, but surgical excision is generally indicated due to the negative cosmetic effect and influence on oral hygiene. The risk of recurrence is high, particularly when the laesion is not radically removed.

Bacterial colonization of the peri-implant sulcus in dentate patients: a prospective observational study.

OBJECTIVES: The aim of the present study was to compare the composition of the periodontal microflora at baseline (T0) with the submucosal microflora at least 1 year after implant placement (T1) in periodontally healthy patients. MATERIAL AND METHODS: For all 169 consecutive patients that visited our clinic during 1 year, we determined their periodontal parameters, implant mucosal index, and presence of implant calculus. At T0, self-reported smoking status was recorded and subgingival and submucosal biofilm samples were obtained and analyzed for the presence and numbers of selected periodontal pathogens. All measurements were repeated at T1. RESULTS: One hundred twenty patients completed the study. Periodontal parameters were stable or had improved at T1. The total bacterial load was lower at implant sites (P < 0.05). The prevalence of Porphyromonas gingivalis was low at baseline, but at T1, detection rate and numbers were higher at implant sites compared to dentate sites. At T1, the frequency of detection of P. gingivalis (P = 0.01), Parvimonas micra (P = 0.018), and Fusobacterium nucleatum (P = 0.035) was higher in smoking patients (n = 23) than in non-smokers (n = 97). CONCLUSIONS: Colonization of the submucosal peri-implant area is similar to the composition of subgingival microbiota. Smoking has a measurable effect on the colonization of implant-associated biofilms and may select for P. gingivalis, P. micra, and F. nucleatum. CLINICAL RELEVANCE: The colonization of implants by well-known periodontal pathogens is very similar to that in normal dentition, also in a healthy cohort. Smoking status was related with the prevalence of periodontal pathogens where smokers harbored more often periodontal pathogens such as P. gingivalis, P. micra, and F. nucleatum.