The feasibility of using Patients Concerns Inventory (PCI) in managing Malaysian oral cancer patients

The feasibility of using the Patients Concerns Inventory (PCI) to identify oral cancer patient concerns during consultation in oral and maxillofacial specialist clinics in Malaysia was assessed. A cross-sectional study was conducted using a consecutive clinical sampling technique of all new and follow-up oral cancer patients. Surgeons and counter staff were also recruited. Two-thirds of patients were elderly, 63.9% female, 55.6% Indian, 63.9% of lower-level education, and half had the lowest level household income. Patient status was mostly post-treatment (87.5%) and most were at cancer stage III/IV (63.9%); 59.7% had surgery. Patients took an average 5.9 min (95% CI 5.1–6.7 min) to complete the PCI. Physical domain appeared highest (94.4%); social/family relationship issues (4.2%) were lowest. Significant associations included patient age–personal function (P = 0.02); patient education level–emotional status (P = 0.05) and social/family relationship issues (P = 0.04), and patient TNM staging–personal function (P = 0.03). The patients’ mean feasibility score for the PCI was 5.3 (95% CI 5.1–5.5) out of 6. Patients (93.1%) and surgeons (90%) found the PCI to be feasible. Only 57.1% of counter staff agreed on the use of the PCI during patient registration. Overall, the PCI was considered feasible, thus favouring its future use in routine oral cancer patient management.     

Evaluation of airflow characteristics before and after septoplasty in unilateral cleft patients with a deviated nasal septum: a computational fluid dynamics study

The aim of this study was to evaluate changes in airflow characteristics before and after septoplasty in unilateral cleft lip and palate (UCLP) patients using computational fluid dynamics (CFD) models. The study was designed as a prospective cohort study involving pre- and postoperative computed tomography data from 12 UCLP patients with a deviated nasal septum who underwent septoplasty. CFD analysis of nasal airflow was conducted to study changes in velocity, pressure, volume, nasal resistance, and wall shear stress of the nasal domain before and after surgery. The study results demonstrated a statistically significant difference in pressure drop after septoplasty: median 116.10 Pa (interquartile range (IQR) 749.02 Pa) preoperative compared with 43.39 Pa (IQR 349.01 Pa) postoperative (P =  0.004). Maximum wall shear stress was found to be approximately three times lower after septoplasty: median 6.15 Pa (IQR 1908.62 Pa) preoperative versus median 2.51 Pa (IQR 540.06 Pa) postoperative (P = 0.002). Changes in nasal resistance were also found to be statistically significant: median 460.59 Pa·s/l (IQR 1946.99 Pa·s/l) preoperative versus median 166.61 Pa·s/l (IQR 694.08 Pa·s/l) postoperative (P = 0.04). These values demonstrate significant changes in flow dynamics after surgery indicative of a more uniform airflow pattern and stabilization of the nasal mucosa.     

Complications and outcome after free flap surgery for cancer of the head and neck

We retrospectively studied 136 patients who had free flap reconstruction for cancer of the head and neck at a single centre (2008–2015) to evaluate complications, assess factors associated with them, and analyse their impact on outcome. Preoperative and perioperative data, and surgical and medical complications were recorded, and the impact of the complications on duration of hospital stay and survival were assessed. A total of 86 (63%) patients had complications. Compared with those who did not, they had a higher rate of alcohol abuse (21/86, compared with 5/50, p = 0.039), longer operations (median (IQR) 565 (458–653 compared with 479 (418–556) minutes, p < 0.001), and greater intraoperative loss of blood (725 (400–1150) compared with 525 (300–800) ml, p = 0.042). Complications were more common in patients who had fibular flaps and T4 disease (22/86 compared with 4/50, p = 0.010; 47/80 compared with 16/47, p = 0.015, respectively). Those who had complications also stayed in hospital longer (median (IQR) 9 (7–12) compared with 15 (10–21) days, p < 0.001). Cumulative mortality was higher in patients with late complications (those that occurred after the fourth postoperative day) (61% compared with 36%, p = 0.004). In conclusion, complications in more than half the patients were related to alcohol abuse, a more complicated intraoperative course, and fibular flaps. Complications were associated with a longer hospital stay, and survival was higher in those who did not have late complications than in those who did.     

Using the Patient Concerns Inventory in the identification of fatigue following treatment for head and neck cancer

Fatigue has a profound impact on health-related quality of life (HRQOL). The aim of this study was to describe the clinical characteristics and HRQOL of head and neck cancer patients who raised the issue of fatigue on the Patient Concerns Inventory (PCI) at their review consultation. Eight consultants were randomized to use the PCI as part of a cluster-controlled trial. Patients also completed the University of Washington Quality of Life version 4 (UWQOL), EQ-5D-5L (EuroQol Group), and Distress Thermometer questionnaires. The study included 140 patients who attended clinics at a median of 108 (interquartile range 70–165) days after the end of treatment. The PCI item ‘fatigue’ was the sixth most commonly selected, by 29% (n = 40). Those with advanced tumours were more likely to have selected the item (30/84, 36% vs 10/56, 18%; P = 0.02), as were those treated with radiotherapy ± chemotherapy (34/87, 39% vs 6/53, 11%; P < 0.001). The PCI fatigue group reported significantly worse overall quality of life, social–emotional and physical function composite scores (UWQOL), Distress Thermometer, and EQ-5D-5L. PCI fatigue was common in those with sleeping, nausea, mood, depression, mobility, breathing, and energy level concerns. In conclusion, given the problems associated with fatigue, it is appropriate to screen and seek interventions that might help patients address this.     

Factors contributing to delayed decannulation of temporary tracheostomies following free tissue reconstructive surgery for head and neck cancer

Temporary tracheostomies (TT) are performed to secure the airway perioperatively and postoperatively in head and neck cancer patients undergoing tumour resection and free tissue reconstructive surgery. Patients report that having a TT is unpleasant and they appreciate its removal at the earliest opportunity. Early removal not only improves patient satisfaction but should allow for a more rapid recovery. The aim of this prospective study was to assess factors that contribute to delays in decannulation following TT and hence to provide an insight into the factors that will support earlier decannulation when it is safe to do so. Consecutive patients who had TT over a six-month period were included. Delayed decannulation was defined as that after day seven postoperatively. There were 42 patients with a median (IQR) age of 70 (60-74) years, 26 of whom were men. The tracheostomy was surgical in 29 and percutaneous in 13. The median (IQR) time to decannulation was 4 (3-5) days (range 1-11 days). Seven patients had delayed removal (7-11 days), the reasons being hospital-acquired pneumonia (HAP) (n = 4), prolonged stay in the high dependency unit (HDU) following postoperative myocardial infarction and cardiac arrest (n = 1), failure to tolerate TT occlusion (n = 1), and not stated (n = 1). There were early postoperative complications in 14 patients but despite this seven decannulations were still performed within two and six days. Additional multiprofessional assessment over weekends is likely to facilitate earlier decannulation. As some TTs are removed after a few days there is a need for better selection to avoid their use in certain patients.     

Two-week rule: suspected head and neck cancer referrals from a general medical practice perspective

The two-week rule (2WR) referral system was designed to fast-track patients with suspected malignancies to secondary care services to facilitate prompt investigation and management, the ultimate goals being early detection and improved survival. Patients with symptoms of head and neck cancer primarily present to the general practitioner (GP) who has an important role in the identification of high-risk patients for prompt management. This paper reports urgent 2WR referrals from primary care to highlight difficulties in the referral process. Data were collected from three GP practices (16 GPs) in Merseyside that all used the EMIS Web system (EMIS Health). All patients who were referred on the 2WR pathway in a two-year period from January 2017 were identified (n = 113). The conversion rate for malignant diagnosis was 5.5% (95% CI: 2.0 to 11.5%). Those with multiple symptoms had a higher rate of malignancy (16%, 3/19) than those with a single symptom (3%, 3/91) (p = 0.06). In total, 76% of patients had had no treatment before referral. The duration of symptoms ranged from 1 - 208 weeks (median (IQR) 6 (4-12) weeks). Common benign symptoms included laryngopharyngeal reflux (n = 27), thyroid lesion (n = 9), and neck lymph node (n = 7). The diagnosis of head and neck cancer in primary care is challenging. Initiatives to try to increase the cancer conversion rate are required, but they run the risk of missed diagnosis and increased delay. Sufficient resources are needed in secondary care to ensure the timely assessment of patients who are referred on the 2WR pathway.     

New surgical instrument for the treatment of condylar fractures: the digitised condylar retractor

Reduction is one of the most difficult steps in condylar fracture surgery, and a key factor governing the postoperative outcome. In this study we evaluated quantitatively the effects of a digitised condylar retractor on the duration and rate of reduction. In a prospective, randomised, controlled clinical trial, 48 patients with unilateral condylar fractures who were listed for surgical treatment were randomised to an experimental and a control group (n = 24 in each). The experimental group was treated with a digitised condylar retractor, and the control group with traditional surgical instruments only. The primary outcome variables were duration and rate of reduction. The continuity correction chi squared test and independent samples t test were used for statistical analyses. The results showed that the mean reduction time was 21.3 minutes in the experimental group and 42.4 minutes in the control group (p = 2.48*10⁻⁸, <0.001). The reduction rate was 21/24 in the experimental group and 17/24 in the control group (p = 0.16). The results indicated that the mean duration of reduction was significantly shorter, and the reduction rate was higher, in the experimental group than among controls. In conclusion, the digitised condylar retractor can assist surgeons to improve efficiency and accuracy in the reduction of condylar fractures, so it merits promotion as an aid to their surgical treatment.     

Survival of oral mucosal melanoma according to treatment,tumour resection margin,and metastases

Because of the poor prognosis and of oral mucosal melanoma, and patients’ short survival, large, randomised, clinical studies are difficult. We have investigated its demographic characteristics and analysed the effect of treatment, resection margins, and metastases on survival. We recorded age, sex, site of primary tumour, and types of treatment, survival, and metastases in 74 patients treated at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Survival was analysed based on bony invasion, depth of invasion, and resection margins, and we found that it varied depending on the primary site (p = 0.002), and declined with liver (p = 0.001) or brain (p = 0.033) metastases. The two-year survival according to the primary site was as follows: palate 85% (n = 32), anterior maxillary gingiva 53% (n = 13), mandible 58% (n = 13), and posterior maxillary gingival 74% (n = 10) and buccal mucosa 50% (n = 4). The two-year survival was 34% (n = 8) in patients with liver metastases and 23% (n = 7) in patients with brain metastases. In cases of bony invasion (p = 0.005), depth of invasion (p = 0.042), unclear resection margin (p = 0.023), or higher T stages (p = 0.009), the survival declined considerably. Neck dissection did not affect survival (p = 0.343). Survival of the patients given chemotherapy was significantly lower (p = 0.013) and the two-year survival was 54.0%. The patients given radiotherapy showed no significant difference in survival compared with those not given radiotherapy (p = 0.107). In conclusion, primary site, bony invasion, resection margins, depth of invasion and systemic metastases were critical to predict prognosis and selection of treatment of oral mucosal melanoma.     

Effects of polyphosphates and fluoride on hydroxyapatite dissolution: A pH-stat investigation

ObjectivesThis study investigated the immediate and sustained effect of sodium trimetaphosphate (TMP) and sodium hexametaphosphate (HMP) associated or not with fluoride (F) on hydroxyapatite (HA) dissolution using an erosion-like model, considering as well as the influence of salivary coating.DesignBaseline dissolution rates were determined for HA discs using a pH-stat system. In the first set of experiments, HA discs were treated with 1100 μg F/mL, 1% or 8% of HMP, 1% or 8% of TMP and 1100 μg F/mL associated with 1% or 8% of HMP or TMP, totaling 9 groups (n = 8). In a second phase, HA discs were kept in pooled human saliva at 37 °C for 2 h before treatment with deionised water and 1100 μg F/mL associated with 1% or 8% of HMP or TMP, totaling 5 groups (n = 8). The post-treatment dissolution rate was determined from three consecutive 30-min assays. Data were analysed using 2 and 3-way ANOVA followed by Fisher and Holm–Sidak methods, respectively (α = 0.05).ResultsAll test solutions promoted reduction in HA dissolution rate when compared to baseline control in the first post-treatment run (p < 0.001). However, a synergistic effect was only observed between fluoride and 1% HMP. Moreover, the duration of inhibitory effect was greater when 8% HMP and 1 or 8% HMP associated with F were assessed (p < 0.001). The presence of salivary coating led to higher protection for all groups when compared to discs without coating (p < 0.001).ConclusionThe reduction of HA dissolution rate, as well as the duration of this effect were influenced by fluoride, type and concentration of phosphate salt and the presence of a salivary coating.     

Quality of life of Japanese elderly oral cancer patients during the perioperative period

Japan’s aging society has an increasing incidence of oral cancer. This study investigated perioperative changes in quality of life (QoL) among 172 oral cancer patients (elderly ≥75 years vs non-elderly <75 years), pre-treatment, at treatment completion, and at 1, 3, and 6 months post-treatment, using the following Functional Assessment of Cancer Therapy – Head and Neck (FACT-H&N) subscales: physical well-being (PWB), social/family well-being (SWB), emotional well-being (EWB), functional well-being (FWB), additional head- and neck-specific concerns (H&N). SWB (P = 0.026), H&N (P = 0.024), and total FACT-H&N (P = 0.009) scores were significantly lower in the elderly group than in the non-elderly group at 6 months post-treatment, especially for mastication items (H&N1, P = 0.047; H&N11, P = 0.004), but not for swallowing items (H&N5 and H&N7, both P >  0.05). PWB (P =  0.004), EWB (P <  0.001), and FWB (P =  0.022) scores in the non-elderly group were significantly higher at 6 months post-treatment than before treatment. In the elderly group, no subscale showed a better score at 6 months post-treatment. Post-treatment QoL in elderly oral cancer patients did not improve, unlike in non-elderly patients.     

Stress hyperglycaemia or diabetes mellitus in cervicofacial infections? A Maxillofacial Surgery Trainee Research Collaborative (MTReC) study

Diabetes mellitus (DM) is thought to be associated with poor outcomes in cervicofacial infections (CFI), yet little is known about the prevalence of DM in these cases. Stress hyperglycaemia (SHG), a normal physiological response to inflammation, is distinct from DM, though they overlap and may be conflated. We aimed to establish the prevalence of DM and SHG in CFI, and to determine the effect of each on severity of disease and outcome measures. The Maxillofacial Surgery Trainee Research Collaborative (MTReC) carried out an audit of all patients with CFI admitted to 25 hospitals between May and October 2017. To the best of our knowledge this created the largest prospective database on CFI, with information collected on presentation, source of infection, biological data, and outcomes. We recorded 1002 admissions, of which 78 (7.8%) had DM. Random blood glucose was measured on admission in 401 patients (40%), of which 45 (11%) displayed SHG. Patients diagnosed with DM were more likely to have infections arising from a salivary source (13% vs 4%, p < 0.00), more returns to theatre (9% vs 2%, p < 0.00), and a longer hospital stay (median (range) 2 (0-34) vs 1 (0-139) day, p = 0.01) than non-DM patients. In contrast, patients with SHG had more severe disease (multiple fascial spaces involved in 59% vs 19%, p = 0.01, and systemic inflammatory response syndrome present in 66% vs 45% p = 0.03), but did not have significantly more returns to theatre (2% vs 3%, p = 0.91) or longer stays in hospital (median (range) 1 (0-63) vs 1 (0-6), p = 0.55) than normoglycaemic patients. The prevalence of DM in our cohort was only marginally higher than in the general population, despite previous retrospective case reviews suggesting a significantly higher prevalence. SHG was not associated with poor outcomes in our cohort, but is likely to be associated with a small increased risk of subsequent diagnosis of DM, which can be quantified using a calculator tool. On discharge, it is important to give appropriate advice about diet, lifestyle, exercise, and weight loss to all patients with CFI.     

Association between facial measurements and polymorphisms in human epidermal growth factor and transforming growth factor β1

The aim of the study was to evaluate the association between genetic polymorphisms in human epidermal growth factor (EGF) (rs4444903) and transforming growth factor β1 – (TGF-β1) (rs1800470) with facial measurements in patients with dentofacial deformities. A total of 144 adult patients with dentofacial deformities were included. Facial linear and angular measurements were traced in lateral cephalometric radiographs used Dolphin 2D software. Cells from oral mucosa were collected for DNA to be extracted. The polymorphisms were genotyped using real-time polymerase chain reaction (PCR). Probabilites of less than 0.05 were accepted as significant. The rs4444903 heterozygous patients had a decrease in the mandibular length (p = 0.043) and the length of the mandibular base (p = 0.008), and homozygous A patients also had a reduction in the length of the mandibular base (p = 0.013) compared with homozygous G patients. Patients AG had an increase in measurement of the anterior facial height (p = 0.032) and in ANS-Me distance (p = 0.022) when compared with homozygous A. To the rs1800470, heterozygous patients had an increase in the length of the mandibular base (p = 0.043) when compared with homozygous A. Heterozygous AG patients had an increase in angular measurements in TGF-β1 polymorphism for the upper gonial angle, when compared with the homozygous AA (p = 0.032). Genetic polymorphisms in EGF and TGF-β1 are associated with facial measurements in a Brazilian population of patients with dentofacial deformities.     

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 >2 mm. 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 1.05 mm (interquartile range (IQR) 0.45–2.72 mm) in the patient-specific osteosynthesis group and 1.74 mm (IQR 1.02–3.02 mm) in the control group. The cranial–caudal deviation was 0.87 mm (IQR 0.49–1.44 mm) and 0.98 mm (IQR 0.28–2.10 mm), respectively, whereas the left–right translation deviation was 0.46 mm (IQR 0.19–0.96 mm) in the patient-specific osteosynthesis group and 1.07 mm (IQR 0.62–1.55 mm) 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 3.70 mm.     

High levels of socioeconomic deprivation do not inhibit patients’ communication of concerns in head and neck cancer review clinics

To examine associations between socioeconomic status and the extent to which patients with cancer of the head and neck expressed concerns to surgeons during routine follow-up clinics, we analysed audio recordings of 110 consultations with one consultant. We used the Verona Coding Definitions of Emotional Sequences (VRCoDES) to measure communication between the doctor and the patient, and grouped the English indices of multiple deprivation (IMD) 2015 scores into deciles to compare the VRCoDES with socioeconomic status. There were no significant correlations between IMD decile and the number and type of cues and concerns, or the type of response by the consultant, but there was a positive correlation between IMD decile and duration of appointment (r = 0.288, p < 0.01). When the duration of appointment was controlled for, there was a negative correlation between IMD decile and number of cues and concerns (r = ?0.221, p < 0.05). These findings question the assumption that socioeconomic status is associated with a patient’s willingness to express concerns. Shorter consultations suggest that less time is spent responding to their concerns or building a rapport. Clinicians might find it advantageous to adopt strategies that will improve their understanding of these patients and help them to communicate more effectively.     

Mandibular reconstruction using the deep circumflex iliac artery free flap: effect of the length of bone harvested on donor site morbidity

The aim of this study was to assess the amounts of pain and morbidity that are associated with the length of the harvested anterior iliac bone graft (cm), and their effect on the contour of the donor site and activities of daily life. A total of 62 patients who had mandibular reconstruction using an iliac bone graft were enrolled in this study at the Wuhan University Hospital. The same surgical standards were used throughout. We divided the patients into two groups depending to the length of the graft (<9 cm or 9 cm or more). The amount and duration of the pain, the time necessary to walk normally, abnormalities of sensation, contour of the donor site, length of the scar, and the patients’ satisfaction with the donor site were evaluated, and outcomes in the two groups compared. The worst pain after operation (p = 0.001) the length of the scar (p = 0.001), and the time needed before the patients were able to walk (p = 0.001) differed significantly between the two groups. There was no significant difference between the two groups regarding other complications. The anterior iliac crest might still be considered to be an ideal donor site for large mandibular defects.     

Metabolic control and periodontal treatment decreases elevated oxidative stress in the early phases of type 1 diabetes onset

ObjectiveRecently, increasing concern has been focused on the contribution of oxidative stress in the pathology of periodontal disease and diabetes mellitus. Firstly, the present study aimed to analyze gingival crevicular fluid (GCF), salivary, and serum oxidative status in children with type 1 diabetes mellitus (T1DM) at diagnosis and systemically healthy children with and without gingivitis. Additionally, the diabetic patients were reevaluated after diabetes and periodontal treatment.DesignThe study groups were composed of 32 T1DM patients at diagnosis, and age- and gender-matched thirty-six systemically healthy children with (G) and without (H) gingivitis. The diabetic patients who took insulin therapy (1.5 units/kg/day totally) and periodontal treatment (oral hygiene education with professional scaling) were reevaluated after 3 months. The levels of total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were recorded.ResultsGCF, salivary, and serum OSI were elevated in group T1DM compared to the other groups at baseline (p < 0.05), and decreased in group T1DM at reevaluation compared to baseline (p < 0.05). GCF OSI was positively correlated with periodontal clinical parameters (p < 0.05). Glycated hemoglobin was positively correlated with GCF TOS (r = 0.302, p = 0.007), GCF OSI (r = 0.346, p = 0.002), salivary TOS (r = 0.326, p = 0.046), and serum TOS (r = 0.239, p = 0.044).ConclusionThe instability in the oxidative status that accompanies diabetes may be considered a significant pathogenic factor of diabetes-related periodontal inflammation.     

Effects of low-level laser therapy on the proliferation and apoptosis of gingival fibroblasts treated with zoledronic acid

Low-level laser therapy (LLLT) has been indicated as an adjuvant therapy for bisphosphonate-induced osteonecrosis. However, the effects of LLLT on bisphosphonate-treated cells are not yet clear. This study evaluated the effects of LLLT on the proliferation and apoptosis of gingival fibroblasts treated with zoledronic acid (ZA). Cells were exposed to ZA at 5 μM for 48 h. Irradiation was performed using a laser diode prototype (LaserTABLE, InGaAsP; 780 nm ± 3 nm, 25 mW) at 0.5 or 3 J/cm², three times every 24 h. Cell proliferation and apoptosis were evaluated by fluorescence microscopy. Data were analyzed by Mann–Whitney test at the 5% level of significance. ZA decreased cell proliferation to 47.62% (interquartile range (IQR) 23.80–57.14%; P = 0.007) and increased apoptosis of gingival fibroblasts to 27.7% (IQR 20.9–33.4%; P = 0.0001). LLLT increased cell proliferation compared with non-irradiated cells, at 0.5 J/cm² (57.14%, IQR 57.14–71.43%; P = 0.003) and at 3 J/cm² (76.19%, IQR 61.90–76.19%; P = 0.0001), but did not increase cell proliferation in ZA-treated cells. Irradiated fibroblasts presented lower apoptosis rates than the ZA-treated cells, but apoptosis was no different in ZA-treated cells compared to those that were ZA-treated and also irradiated.     

Comparison of intraoperative outcomes with single and double puncture techniques of arthrocentesis of the temporomandibular joint

Evidence of differences in operator-related outcomes between single and double puncture arthrocentesis is limited. The purpose of this prospective study was to compare intraoperative outcomes with single puncture types 1 and 2, and double puncture, arthrocentesis. A total of 59 patients with 60 temporomandibular joints (TMJ) were treated sequentially by single puncture type 1 (n = 20), single puncture type 2 (n = 20), and double puncture arthrocentesis (n = 20). Total operating time, incidence of dislocation of the needle, preauricular swelling, and ease of operation were compared. Single puncture type 2 arthrocentesis took significantly less time than type 1 (p < 0.0001) or double puncture arthrocentesis (p < 0.0001), but there was no difference in operating time between single puncture type 1 and the double puncture technique (p = 0.25). There were significantly fewer dislocations of the needle with single puncture type 1 (p = 0.041) and single puncture type 2 (p = 0.033) than with double arthrocentesis. Single puncture type 2 arthrocentesis was easier than the single puncture type 1 (p = 0.001) or double puncture technique (p < 0.0001). Extravasation of fluid caused swelling in seven patients after double puncture, and in three patients each after single puncture types 1 and 2, arthrocentesis. Our results indicate that the single puncture type 2 technique is easiest and requires the least operating time. There was no difference between single puncture type 1 and double puncture arthrocentesis in terms of operating time or ease of the procedure. There were fewer operative dislocations of the needle with the single than with the double puncture technique.     

Investigation into the validity of WearCompare,a purpose-built software to quantify erosive tooth wear progression

ObjectivesThe use of surface matching software with intraoral scanners is developing rapidly which increases the need for accessible, accurate and validated measurement software. This investigation compared the current gold-standard Geomagic Control software to a purpose-built software “WearCompare”.MethodsArtificially created occlusal defects of a known size were created on 10 natural molar teeth scanned with a structured-light model-scanner (Rexcan DS2, Europac 3D, Crewe). The volume change, maximum profilometric loss and mean profilometric loss were obtained from both Geomagic Control (3D Systems, Darmstadt, Germany) and WearCompare (leedsdigitaldentistry.com). Duplicated datasets were randomly repositioned and re-alignment performed. The effect of the re-alignment was calculated by analysing differences between the known defect size and defect size after re-alignment using the same measurement metrics. Lastly, clinical wear measurements were compared on natural molar surfaces (n = 60) over 6 months using study models collected from a previous longitudinal trial. Data analysis was performed in SPSS v25 (paired t-tests, Pearson correlations, p < 0.05).ResultsMeasurement correlation between the softwares was greater than 0.97 (p < 0.001) for all measurement metrics. The volume change error (SD) after alignment was −0.67 mm³(1.14) for Geomagic and −0.06 mm³(0.93) for WearCompare (p = 0.140 and r = 0.065, p = 0.86). Measurement errors were observed after alignment in both softwares and no statistical differences were observed between softwares. The volume change on the clinical dataset over 6 months was +0.29 mm³(3.97) in Geomagic and −0.30 mm³(1.82) for WearCompare (p = 0.19 and r = 0.61, p < 0.001). The mean profile gain was 42.86 μm(40.19) for Geomagic and 32.17 μm(23.72) for WearCompare (p = 0.048). Correlations between the softwares were greater than 0.6 for all measurement metrics except for mean profile gain.SignificanceWearCompare is a comparable tool to Geomagic for quantifying erosive tooth wear. WearCompare reported statistically less profile gain indicating less error but further research is needed to reduce the human errors in both softwares.