Effects of fixed retainers on gingival recession - a 10-year retrospective study.

OBJECTIVE: The aetiology of gingival recessions is not fully understood, and no evidence has yet emerged of a single predisposing factor that instigates this apical shift of the gingival margin. Nonetheless, both fixed retainers and orthodontic treatment have been cited as potential risk factors. The aim of this study was to assess the effects of orthodontic treatment and orthodontic fixed retainers on gingival recessions. SUBJECTS AND METHODS: In total, 105 patients at the Department of Orthodontics at the University of Gothenburg who had undergone orthodontic treatment between 1995 - 2003 were included in this study. Intraoral photographs of the anterior segment and study casts acquired at baseline (pre-treatment), post-treatment and at the 10-year follow-up were used as recorded measurements of gingival recession and orthodontic treatment. At the 10-year follow-up, the patients were divided into two groups based on: long-term (10 years) presence of a fixed retainer [orthodontic treatment and retainer (OR) group; N = 76]; and short-term (<5 years) presence of a fixed retainer [orthodontic treatment (O) group; N = 57]. These groups were compared to a control group (C) of untreated subjects (N = 29). RESULTS: In the anterior segment, gingival recessions were not present at baseline and post-treatment between the two orthodontically treated groups. At the 10-year follow-up, there was no statistically significant difference between the two orthodontically treated groups and the controls. CONCLUSIONS: Orthodontic treatment per se does not increase the risk for gingival recessions, nor does the use of fixed retainers following orthodontic treatment.

The influence of intraoral cooling on taste and smell perception.

BACKGROUND: Cryotherapy using ice chips has been successfully used to prevent chemotherapy-induced oral mucositis. Although effective, concerns have been raised that the low temperatures that are obtained in the oral mucosa during cooling may be potentially harmful to taste and smell perception. Thus, this study aimed to investigate whether intraoral cooling permanently affects taste and smell perception. SUBJECTS AND METHODS: Twenty subjects inserted an ounce of ice chips and moved the ice around in the mouth to cool as large a part of the oral mucosa as possible. Cooling continued for 60 min. At baseline (T0 - minutes), and following 15, 30, 45, and 60 min of cooling, taste and smell perception were registered, using the Numeric Rating Scale. The same procedures were repeated 15 min (T75 - minutes) after completion of cooling. Taste and smell were evaluated using four different solutions and a fragrance, respectively. RESULTS: A statistically significant difference was seen for taste perception with Sodium chloride, Sucrose, and Quinine at all the follow-up time points tested as compared to baseline (p < .05). Citric acid and smell perception proved to be significantly different from baseline following 30 min of cooling. When the same assessments were carried out 15 min following completion of cooling, i.e. T75, all taste and smell perceptions had recovered to some extent. For taste perception, however, a statistically significant difference was still seen for all solutions tested as compared to baseline (p < .01). CONCLUSION: In healthy individuals, intraoral cooling with IC leads to a temporary reduction in taste and smell perception, with a tendency to return to baseline values.

Cooling of the oral mucosa to prevent adverse effects of chemotherapeutic agents: An in vitro study.

BACKGROUND: The cytotoxic effect of chemotherapeutic agents to the oral mucosa, as a side effect of cancer treatment, is a major problem. Cooling the oral mucosa using ice chips in conjunction with chemotherapy is known to reduce the severity of oral mucositis. However, although the use of ice chips is of clinical value, this method of cooling has inherent problems including discomfort for the patient, non-uniformity and fluctuations in cooling temperature throughout the oral cavity. Furthermore, despite being used clinically, it is not known what reduction in temperature is required to prevent oral mucositis. The aim of this study was therefore to determine in vitro if the cytotoxic effect of 5-fluorouracil (5-FU) on the oral mucosa could be reduced by lowering the temperature during chemotherapeutic treatment. METHODS: Tissue-engineered oral mucosal (TEOM) models were incubated at 20, 25, 30 or 35°C for 30 minutes followed by exposure to a clinically relevant concentration of 5-FU (162 µg/mL) for 2 hours and compared with untreated models (35°C). Cell viability and inflammatory cytokine production (IL-6 and TNF-α) were measured using PrestoBlue® and ELISA, respectively. RESULTS: TEOM models incubated at 20°C showed an increased cell viability and had a reduced IL-6 and TNF-α production compared to models treated with 5-FU incubated at 35°C. CONCLUSION: This study demonstrates a reduced cytotoxic effect to the TEOM by reducing the temperature of the tissue during chemotherapy treatment and suggests that decreasing the temperature to 20°C could have clinical advantages.

Efficacy of a novel device for cryoprevention of oral mucositis: a randomized, blinded, multicenter, parallel group, phase 3 trial.

Cryoprevention (CP) using ice (IC) is an effective strategy to prevent chemotherapy-induced oral mucositis (OM). However, the use of IC may cause adverse reactions and requires water of safe quality to minimize risk of serious infections. This randomized, blinded, parallel group, phase 3 trial was conducted in five Scandinavian centers. Eligible patients were diagnosed with multiple myeloma or lymphoma, scheduled to receive conditioning with high-dose chemotherapy prior to autologous hematopoietic stem cell transplantation (ASCT). Patients were assigned to cooling with IC or a novel intraoral cooling device (ICD). The primary outcome was the highest OM score during the study period, expressed as peak value on the Oral Mucositis Assessment Scale (OMAS-total). When the entire study population (n = 172) was analyzed for peak OMAS-total, the two cooling methods were equally effective. However, when the lymphoma group was analyzed separately, the ICD significantly reduced the peak OMAS-total score to a greater extent compared to IC (x̄ ± SD; 1.77 ± 1.59 vs. 3.08 ± 1.50; p = 0.047). Combined with existing evidence, the results of the present trial confirm that CP is an effective method to prevent OM. ClinicalTrials.gov. NCT03203733.

Three-Dimensional Bioprinting Using a Coaxial Needle with Viscous Inks in Bone Tissue Engineering - An In vitro Study.

INTRODUCTION: Vascularized autologous tissue grafts are considered "gold standard" for the management of larger bony defects in the craniomaxillofacial area. This modality does however carry limitations, such as the absolute requirement for healthy donor tissues and recipient vessels. In addition, the significant morbidity of large bone graft is deterrent to fibula bone flap use. Therefore, less morbid strategies would be beneficial. The purpose of this study was to develop a printing method to manufacture scaffold structure with viable stem cells. MATERIALS AND METHODS: In total, three different combinations of ground beta tri-calcium phosphate and CELLINK (bioinks) were printed with a nozzle to identify a suitable bioink for three-dimensional printing. Subsequently, a coaxial needle, with three different nozzle gauge combinations, was evaluated for printing of the bioinks. Scaffold structures (grids) were then printed alone and with additional adipose stem cells before being transferred into an active medium and incubated overnight. Following incubation, grid stability was evaluated by assessing the degree of maintained grid outline, and cell viability was determined using the live/dead cell assay. RESULTS: Among the three evaluated combinations of bioinks, two resulted in good printability for bioprinting. Adequate printing was obtained with two out of the three nozzle gauge combinations tested. However, due to the smaller total opening, one combination revealed a better stability. Intact grids with maintained stability were obtained using Ink B23 and Ink B42, and approximately 80% of the printed stem cells were viable following 24 hours. DISCUSSION: Using a coaxial needle enables printing of a stable scaffold with viable stem cells. Furthermore, cell viability is maintained after the bioprinting process.

Protocol for a randomised controlled trial to study cryoprevention of chemotherapy-induced oral mucositis after autologous stem cell transplantation.

INTRODUCTION: A majority of patients who receive myeloablative therapy prior to hematopoetic stem cell transplantation develop oral mucositis (OM). This adverse cytotoxic effect manifests as oral mucosal erythema and ulcerations and frequently necessitates high doses of morphine for pain alleviation. OM may also interfere with food intake and result in parenteral nutrition, weight loss and impaired quality of life. To date, there have been a few studies of evidence-based interventions for prevention of OM. Cooling the oral mucosa using ice chips in conjunction with chemotherapy is known to reduce the severity of OM although clinical application is still limited due to several disadvantages. The primary endpoint of this study is therefore to evaluate the efficacy of an innovative intraoral cooling device (Cooral) compared with ice cooling in reducing the degree of OM, in patients with myeloma or lymphoma. METHOD AND ANALYSIS: A total of 180 patients from four different university hospitals in Sweden will be randomised to ice or Cooral in a proportion of 1:1. The degree of OM will be assessed at eight intraoral locations, in accordance with the Oral Mucositis Assessment Scale and WHO scale. Patients will be registered beginning at admission and will continue until discharge or until day +28. The primary variable is analysed in a multiple linear regression model. The significance level used is 5%. ETHICS AND DISSEMINATION: The study protocol, questionnaire, diaries and letter of invitation to participants have been reviewed by the local ethical board in Göteborg. The trial results will be published in a peer-reviewed journal and disseminated to participants. TRIAL REGISTRATION NUMBER: NCT03203733; Pre-results. PROTOCOL VERSION: Version 4, 2017-06-05.

Correction to: Innovative intraoral cooling device better tolerated and equally effective as ice cooling.

Unfortunately, the online published article has error in Table 1. The correct Table 1 is given in the following page.

Innovative intraoral cooling device better tolerated and equally effective as ice cooling.

PURPOSE: Most of the patients who receive myeloablative therapy prior to stem cell transplantation develop oral mucositis (OM). This adverse reaction manifests as oral mucosal erythema and ulcerations and may require high doses of morphine for pain alleviation. OM may also interfere with food intake and result in weight loss, a need for parenteral nutrition, and impaired quality of life. To date, there have been very few studies of evidence-based interventions for the prevention of OM. Cryotherapy, using ice chips, has been shown to reduce in an efficient manner the severity and extent of OM, although clinical applications are still limited due to several shortcomings, such as adverse tooth sensations, problems with infectious organisms in the water, nausea, and uneven cooling of the oral mucosa. The present proof-of-concept study was conducted to compare the tolerability, temperature reduction, and cooling distribution profiles of an intra-oral cooling device and ice chips in healthy volunteers who did not receive myeloablative treatment, and therefore, did not experience the symptoms of OM. METHODS: Twenty healthy volunteers used the cooling device and ice chips for a maximum of 60 min each, using a cross-over design. The baseline and final temperatures were measured at eight intra-oral locations using an infra-red thermographic camera. The thermographic images were analysed using two digital software packages. A questionnaire was used to assess the tolerability levels of the two interventions. RESULTS: The intra-oral cooling device was significantly better tolerated than the ice-chips (p = 0.0118). The two interventions were equally effective regarding temperature reduction and cooling distribution. CONCLUSIONS: The intra-oral cooling device shows superior tolerability in healthy volunteers. Furthermore, this study shows that temperature reduction and cooling distribution are achieved equally well using either method.