Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study.

OBJECTIVE: To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America. METHODS: A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square. RESULTS: In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD. CONCLUSIONS: In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

Are intraoral stents effective in reducing oral toxicities caused by radiotherapy? A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Intraoral stents have been provided to minimize acute and chronic toxicities induced by radiotherapy, including oral mucositis, salivary changes, trismus, radiation-related caries, and osteoradionecrosis. However, a systematic review and meta-analysis is necessary to determine their effectiveness. PURPOSE: The purpose of this systematic review and meta-analysis was to determine the effectiveness of intraoral stent use and determine whether these prosthetic devices can reduce radiation dosage to nontargeted oral tissues and adverse effects related to head and neck radiation. MATERIAL AND METHODS: Two independent reviewers made a systematic search for articles published from January 2010 to March 2020 in 3 databases, supplemented by a manual search. Studies were included if they were clinical trials (randomized controlled trials, both prospective and retrospective), published in English, and evaluated radiation dose and oral adverse side effects (acute or chronic) induced by radiotherapy of participants with and without intraoral stents. RESULTS: The search strategy identified 201 studies; of which, 9 were included. A total of 251 participants were evaluated; of whom, 168 (77.3%) used intraoral stents and 57 (22.7%) were treated with radiotherapy without a prosthetic device. A statistically significant difference was found regarding the use of intraoral stents for preventing oral mucositis (P<.001), salivary changes (P=.003), and trismus (P<.02). A funnel plot showed asymmetry among the differences of means in all selected studies. CONCLUSIONS: Intraoral stents have a positive effect on preventing oral mucositis. Further clinical trials are needed to address the flaws identified in the present systematic review.

Impact of head and neck radiotherapy on the longevity of dental adhesive restorations: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Established restorative protocols for patients after head and neck radiotherapy are lacking, increasing the failure rates of dental adhesive restorations. PURPOSE: The purpose of this systematic review and meta-analysis was to analyze the evidence regarding the impact of head and neck radiotherapy on the longevity of dental adhesive restorations. MATERIAL AND METHODS: A search was performed using PubMed, Scopus, and Embase in May 2018 (updated in November 2020). Data extraction was performed regarding the percentage of restoration failure among dental adhesive materials, including glass ionomer cements, resin-modified glass ionomer cements, and composite resins. Risk of bias was assessed by the meta-analysis of statistics assessment and review instrument (MAStARI). Confidence in cumulative evidence was evaluated by the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) protocol. RESULTS: Four studies met the inclusion criteria. All included studies were classified as having a moderate risk of bias and reported results regarding class V restorations. Overall, composite resins presented lower failure rates at 2 years (30%) when compared with resin-modified glass ionomer (41%) and glass ionomer cements (57%). Meta-analysis showed that the risk of failure with glass ionomer cements was greater than with resin-modified glass ionomer cements (RR: 1.71, P<.001). Composite resins presented lower risk of failure when compared with glass ionomer (RR: 2.29, P<.001) and resin-modified glass ionomer cements (RR: 1.30, P=.03). Three studies reported results regarding fluoride compliance, which had a negative effect on the survival rates of glass ionomer and resin-modified glass ionomer cements and a positive effect on composite resin restorations. CONCLUSIONS: The results suggest that composite resin restorations associated with fluoride gel compliance seems to be the best alternative for restoring class V lesions in patients after head and neck radiotherapy. However, the results showed moderate certainty of evidence, which justifies the need for more randomized clinical trials regarding this subject.

Strategic use of obturator prostheses for the rehabilitation of oral cancer patients during the COVID-19 pandemic.

During the current pandemic scenario, maxillofacial rehabilitation specialists involved with supportive care in cancer must transform its practice to cope with COVID-19 and improve protocols that could quickly return the oral function of complex cancer patients who cannot wait for surgical complex rehabilitation. This includes the role of the maxillofacial prosthodontist for the rehabilitation of surgically treated patients with maxillary cancers by the means of filling obturator prostheses that are considered an optimal scientific-based strategy to reduce hospital stay with excellent pain control, oral function (speech, swallowing, mastication, and facial esthetics), psychologic and quality of life outcomes for the patients following intraoral cancer resection. Therefore, the aim of this commentary was to bring new lights to the strategic use of obturator prostheses for the rehabilitation of oral cancer patients during the COVID-19 pandemic as well as to present a protocol for managing such cases.

Is the Fixed Mandibular 3-Implant Retained Prosthesis Safe and Predicable for Full-Arch Mandibular Prostheses? A Systematic Review.

PURPOSE: To evaluate implant and prosthetic survival rates of full-arch rehabilitations retained by three implants in patients with edentulous mandibles. MATERIALS AND METHODS: This systematic review was developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The focused question was: Are fixed mandibular 3-implant retained prostheses safe and predicable for full-arch mandibular prostheses? The Medline/PubMed and Cochrane Library databases were used to conduct the systematic search for clinical trials on fixed mandibular 3-implant retained prostheses published between 1999 and 2020. Only English-language studies that presented information on implant and prosthetic survival were included. RESULTS: A total of 302 studies were identified, of which 13 addressed the inclusion criteria. Additionally, 574 participants were included in these studies. As reported, 73 (4.57%) of 1596 implants failed, with a survival rate of 95.43%. In addition, the mean survival rate of the presented prostheses was 89.66%. The mean marginal bone loss was 1.09 mm. CONCLUSION: Within the limitations of the present review, implant and prosthetic survival rates of fixed mandibular 3-implant retained prostheses were similar to those of full-arch mandibular prostheses retained by four or more implants. Further research exploring the topic is necessary.

Impact of pandemic COVID-19 outbreak on oral mucositis preventive and treatment protocols: new perspectives for extraoral photobiomodulation therapy.

This communication discusses the current challenges of oral mucositis (OM) management during the pandemic COVID-19 outbreak and reflects about an extraoral photobiomodulation protocol as an optimal alternative for preventing and treating OM in advanced cancer patients while minimizing the risk of infection by avoiding intraoral manipulation.

Dental treatment needs in hospitalized cancer patients: a retrospective cohort study.

PURPOSE: The objectives of this study were to describe the distribution and the clinicopathological features of the most common causes for dental treatment needs during the hospitalization of cancer patients. METHODS: A retrospective cohort study of 2664 hospitalized cancer patients that analyzed the main dental treatment needs and dental procedures performed from January 2010 to December 2017. RESULTS: A total of 2664 medical patients were included in this study. Non-Hodgkin lymphoma (17.2%) was the most common cancer type, followed by leukemia (14.8%), and oral and oropharyngeal squamous cell carcinoma (10.5%). The most common reasons for patients' hospitalization were chemotherapy protocols (18.8%), monitoring head and neck surgeries (9.7%), and febrile neutropenia (9.6%). The main motivation for the medical team to request dental evaluation was oral mucositis (22.8%) followed by oral pain or toothache (10.8%) and fungal, viral oral infections or traumatic oral lesions (9.9%). The dental treatment needs most observed were pain due to oral mucositis (17%), dental treatment prior to radiotherapy (RT), chemotherapy (CT) or bisphosphonate therapy (BP) (10.8%), teeth extractions (6.5%), and prophylactic photobiomodulation therapy (6.3%), whereas the most common dental treatments performed were oral hygiene protocols (30.2%), photobiomodulation therapy (prophylactic and curative) (21.7%), and dental treatment prior to cancer treatment initiation (RT, CT, and BP) (9.5%). CONCLUSION: This study can be considered original in the oncologic context, providing new information about the most frequent dental treatment needs among a large population of hospitalized cancer patients.

Impact of Clustering Oral Symptoms in the Pathogenesis of Radiation Caries: A Systematic Review.

Radiation-related caries (RRC) is a disease with a high potential for destruction of the dentition, which impairs quality of life in head-and-neck (HN) cancer (HNC) patients who undergo radiotherapy. In light of the recently described "clustering of oral symptoms theory," the present systematic review (PROSPERO CRD42019132709) aims to assess HN and gastrointestinal (GI) symptom clusters among HNC patients and discusses how these indirect effects of cancer therapy play a pivotal role in the pathophysiology of RRC. The search was performed at PubMed, Scopus, and Embase and resulted in 11 studies that met the inclusion criteria. Data extraction was performed with respect to the presence of HN/GI symptom clusters among HNC patients. The methodological data of the studies included were assessed using the MAStARI and GRADE instruments. The most prevalent reported HN symptoms were dysphagia, xerostomia, and pain. Taste alterations and fatigue were also commonly reported by the patients. Loss of appetite and weight loss were regularly reported in the studies, as well as nausea and vomiting. The results of the present study suggest that HNC treatment generates clusters of oral symptoms, leading to dietary changes, impaired oral hygiene, enamel fragility, and a highly cariogenic oral environment, which may impact the risk for RRC. A better understanding of oral symptom clustering could be of considerable clinical significance for the oral health and quality of life of HNC patients. Therefore, contemporary protocols of RRC prevention must take this broader treatment scenario of symptom clusters such as oral side effects into account.

Use of Resin-Based Provisional Material to Create the Posterior Palatal Seal in Complete Denture Definitive Impressions.

The purpose of this article was to present an alternative procedure using resin-based provisional material to create the posterior palatal seal (PPS). This method offers more practicality in clinical routine and increased control for addition of material to create the PPS when compared to traditional techniques such as the use of impression wax.

Initial investigation of the corrosion stability of craniofacial implants.

STATEMENT OF PROBLEM: Although craniofacial implants have been used for retention of facial prostheses, failures are common. Titanium undergoes corrosion in the oral cavity, but the corrosion of craniofacial implants requires evaluation. PURPOSE: The purpose of this in vitro study was to investigate the corrosion stability of commercially pure titanium (CP Ti) exposed to simulated human perspiration at 2 different pH levels (5.5 and 8). MATERIAL AND METHODS: Fifteen titanium disks were divided into 3 groups (n=5 per group). The control group was subjected to simulated body fluid (SBF) (control). Disks from the 2 experimental groups were immersed in simulated alkaline perspiration (SAKP) and simulated acidic perspiration (SACP). Electrochemical tests, including open circuit potential (3600 seconds), electrochemical impedance spectroscopy, and potentiodynamic tests were performed according to the standardized method of 3-cell electrodes. Data were analyzed by 1-way ANOVA and the Tukey honestly significant difference tests (α=.05). RESULTS: Simulated human perspiration reduced the corrosion stability of CP Ti (P<.05). The SBF group presented the lowest capacitance values (P<.05). SAKP and SACP groups showed increased values of capacitance and showed no statistically significant differences (P>.05) from each other. The increase in capacitance suggests that the acceleration of the ionic exchanges between the CP Ti and the electrolyte leads to a lower corrosion resistance. SAKP reduced the oxide layer resistance of CP Ti (P<.05), and an increased corrosion rate was noted in both simulated human perspiration groups. CONCLUSIONS: Craniofacial implants can corrode when in contact with simulated human perspiration, whereas alkaline perspiration shows a more deleterious effect. Perspiration induces a more corrosive effect than simulated body fluid.

A Simple Technique for Placing Extraoral Implants at an Optimal Position in Orbital Defects.

Translucent acrylic templates have been used to indicate implant positions for implant-retained extraoral prostheses; however, this procedure can be challenging, as the acrylic templates have to be positioned onto reflected skin flaps. The fabrication of an acrylic-based colorless template or duplicating an existing prosthesis can facilitate the location of extraoral implants. Spots can be created on templates to indicate the optimal position of the implants. Afterward, punching the skin to the bone with a very thick sharp needle or a small sharp bur will mark the desired implant position on the bone before reflecting the skin.

Surface Characterization of a Glass Fiber Post after Nonthermal Plasma Treatment with Hexamethyldisiloxane.

PURPOSE: To characterize the surface of glass fiber posts (GFP) after different surface treatments and evaluate which method incorporates higher amounts of silicon (Si) particles, as well as to evaluate the bond strength at the post/ composite-cement interface with four different surface treatments of glass fiber posts luted with composite cement. MATERIALS AND METHODS: Twelve glass fiber posts were obtained from the manufacturer. The posts were randomly distributed into four groups (n = 3): Co (control), no surface treatment; S, 70% alcohol and silane (60 s); HF + S, 10% hydrofluoric acid gel (60 s) and silane (60 s); NTP, nonthermal plasma of hexamethyldisiloxane (HMDSO) associated with argon (30 min). The surface of each GFP was characterized through scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Forty GFPs were randomly divided into 4 groups according the surface treatments (n = 10) and cemented with one composite cement (Rely X U200) into artificial canine teeth. The specimens were placed in a universal testing machine and subjected to tensile testing until failure occurred. Statistical analysis of the atomic percentage and bond strength was performed using ANOVA, followed by the post-hoc Tukey test (p = 0.05). RESULTS: EDS graphics showed that the NTP group had a higher Si atomic percentage (at%) than the other groups (p < 0.001). The HF + S group had a higher Si at% than did the Co and S groups. SEM images illustrated that the surfaces of the GFPs were variously modified after different treatments. The NTP group incorporated higher Si levels on the GFP surface and yielded the highest bond strengths (p < 0.005) compared to the other tested groups. CONCLUSION: Treatment with HMDSO + Ar plasma (NTP) incorporated higher Si levels on the surface of the GFPs without inducing critical defects. NTP treatment promoted better bond strength results when compared to the other tested group when GFPs were cemented with composite cement.

Immediate Dental Implant Placement After Removal of Complex Odontoma.

The aim of the authors was to report a clinical case about immediate implant placement after the removal of complex odontoma. A 35-year-old female patient presented to private service complaining about absence of lower right first premolar. The computed tomographic showed radiopaque attenuation, surrounded by a narrow radiolucency in the area of dental absence, suggesting a mineralized lesion. The surgical removal of lesion was performed by intraoral access with general anesthesia and the implant of 3.75 × 10 mm (Neodent) was placed with the aid of a surgical guide, following the drill sequence established by the manufacturer. No complications were observed after 1 year with the prosthetic rehabilitation.

Stress Distribution in an Implant-Supported Mandibular Complete Denture Using Different Cantilever Lengths and Occlusal Coating Materials.

PURPOSE: The aim of this study was to assess stress distribution in the bone-implant interface of a mandibular implant-supported prosthesis with different cantilever lengths, aesthetic coating materials, and implant abutments. MATERIALS AND METHODS: A photoelastic model of an edentulous mandible, containing 5 external hexagon implants, was constructed. Experimental models were divided into 6 groups: group 1-UCLA component and metal bar; group 2-UCLA component and acrylic resin coating; group 3-UCLA component and porcelain coating; group 4-abutment and metal bar; group 5-abutment and acrylic resin coating; and group 6-abutment and porcelain coating. Forces were applied to the most anterior implant, the most posterior implant, and different cantilever lengths. RESULTS: The results showed a higher number of high-stress fringes as the cantilever length increased. Fringes were better distributed in groups with prostheses composed of acrylic resin and in groups that contained an abutment. CONCLUSION: The stress distribution in the bone-implant interface is improved when the cantilever is eliminated and when abutments in an acrylic resin prosthesis are used.

Assessment of treatment outcomes for facial prostheses in patients with craniofacial defects: A pilot retrospective study.

STATEMENT OF PROBLEM: The longevity of silicone facial prostheses is short, and published data concerning this type of rehabilitation are limited. PURPOSE: The purpose of this retrospective study was to identify predictive variables for prosthetic failure and to highlight the results that can be expected after treatment with silicone facial prostheses. MATERIAL AND METHODS: After institutional approval, patient records from a single Brazilian institution for the time period 2004 to 2015 were assessed. A standardized form was used to collect patient data. Frailty survival modeling (simple random effects survival model) was used to test whether age, sex, type of prosthesis, source of defect, number of implants, and type of retention have a direct impact on the prosthetic failure rate (α=.05). RESULTS: Auricular prostheses were the most frequently fabricated prostheses. Eighty-four prostheses were fabricated during the follow-up period. The overall survival rate for facial prostheses was 34.5%. Color alteration was the most common reason for new prostheses (27.38%). The implant success rate was 98.18%. The number of implants approached statistical significance (P=.06) with a reduced risk of failure when the patient had 2 implants compared with patients with zero implants and patients with more than 2 implants. CONCLUSIONS: Patients should be recalled frequently so that retouches can be performed, avoiding the repeated fabrication of new prostheses. Well-designed studies are necessary to identify more relevant complications and factors that lead to prosthetic failure.

A systematic comparison of bar-clips versus magnets.

STATEMENT OF PROBLEM: Currently, which type of suprastructure is preferred when fabricating implant-retained craniofacial prostheses is unknown. PURPOSE: The purpose of this systematic review was to identify the best retention system (bar-clips versus magnets) for implant-retained craniofacial prostheses. MATERIAL AND METHODS: This systematic review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A systematic search of Medline/PubMed and Web of Science databases for clinical trials was conducted on implant-retained craniofacial prostheses published between 2005 and 2015. English-language studies that directly compared different types of retention systems or presented information on implant survival, periimplant soft tissue reactions, and prosthetic complications were included. Nonclinical studies were excluded to eliminate bias. RESULTS: A total to 173 studies were identified, of which 10 satisfied the inclusion criteria. In total, 492 participants were included in these studies. Four selected studies displayed detailed information with regard to the number of implant failures according to the retention system. As reported, 29 (18.2%) of 159 implants with magnets failed, whereas 25 (31.6%) of 79 implants with bars failed. Overall auricular superstructures showed the highest survival (99.08%). In addition, 55.4% of all participants in the selected studies showed grade 0 of periimplant soft tissue reactions. CONCLUSIONS: A systematic search for clinical studies resulted in few studies with a short-term follow-up and small number of participants. The limited data collected indicated that magnets show fewer complications than bar superstructures; however, no hard conclusions could be drawn. Further research, preferably in the form of clinical trials, is needed to validate these findings.

Obturator Prostheses for Melanotic Neuroectodermal Tumor of Infancy in the Maxilla.

Melanotic neuroectodermal tumor of infancy frequently affects the maxilla. A communication between the oral and nasal cavities can be created by surgery. The authors rehabilitated a young patient with obturator prostheses to correct feeding. The association of the obturators with orthodontic devices provided proper maxillary growth and eruption of teeth. The outcomes were very satisfactory after a 3-year follow-up, and dental implants are planned.

Rehabilitation With Mandibular Implant-Retained Complete Overdenture Using the Association of Two Retention Systems.

This article reports a case of oral rehabilitation with two-implant-retained mandibular overdenture using bar/clip and ball attachment bilaterally on the distal side. A patient aged 69 years, fully edentulous, presented herself to private practice complaining about the instability of mandibular denture. Several possibilities of rehabilitation with advantages and disadvantages were explained to the patient, based in the clinical and radiograph examinations, and patient desire, in which she opted by conventional maxillary complete denture and two-implant-retained mandibular overdenture. Two external hexagon implants of 3.75 × 10 mm were placed in anterior area of mandible. The fabrication of the metal framework with bar/clip and ball attachment bilaterally on the distal side was planned based on prior arrangement of the artificial teeth. Internal adaptation and occlusal adjustments were performed in the day of insertion of finalized denture and instructions about maintenance and sanitation. The patient showed satisfaction with the final result of her treatment, and no complications were observed during this period. The association of bar/clip with ball system may be viable as option of retention for mandibular implant-retained complete overdenture; however, further randomized controlled trials are necessary to obtain detailed knowledge about the topic.