The effects of zinc on radiation-induced dysgeusia: a systematic review and meta-analysis.

PURPOSE: Many head and neck cancer patients who receive radiation therapy experience radiation-induced dysgeusia (RID), which has no standard treatment. The only supplement controlled clinical trials have evaluated for the treatment of RID is zinc. However, the results of these and other studies investigating the use of zinc for RID have been inconsistent. To assess the validity of zinc as a treatment for RID, we conducted a systematic literature search and performed a meta-analysis to determine the extent to which zinc affects RID incidence and the degree to which ongoing RID responds to zinc. METHODS: We searched the Ovid MEDLINE, Ovid Embase, PubMed, and Cochrane Library databases to identify studies investigating the use of zinc-based therapy for RID in head and neck cancer patients treated with radiation that were published between January 1, 2003, and November 9, 2017. Using American Society of Clinical Oncology criteria, we selected studies with a high level of evidence for inclusion in the meta-analysis. RESULTS: Of the 32 full-text articles eligible for inclusion, three were included in the final review and meta-analysis. The meta-analysis showed that, compared with placebo, zinc reduces the incidence of RID (risk ratio, 0.72; 95% confidence interval, 0.67-0.92) but does not improve taste acuity more rapidly following radiation therapy (risk ratio, 2.58; 95% confidence interval, 0.97-6.88). CONCLUSION: Our findings indicate that zinc-based therapy reduces the incidence of RID but has a minimal effect on ongoing RID. Our findings also highlight the need for additional evidence-based research on this topic.

Prosthodontic treatment of a patient with Ewing sarcoma of the left maxillary sinus: A clinical report.

This clinical report describes the prosthodontic rehabilitation of a 22-year-old woman with a substantial treatment history of Ewing sarcoma of the left maxillary sinus. The patient was diagnosed with Ewing sarcoma at the age of 7 years and went through chemotherapy, radiation, surgical resection, and free-flap reconstruction, initially without prosthodontic rehabilitation. The patient aged 22 years was referred to the oral oncology clinic at The University of Texas MD Anderson Cancer Center for prosthodontic treatment. The patient's prosthetic rehabilitation with dental implants and a definitive maxillary obturator prosthesis is presented in detail.

Report of a Powered Air-Purifying Respirator and Its Use in the Dental Setting.

BACKGROUND: Respirators have received much attention since the outbreak of the COVID-19 pandemic. Due to a substantial shortage of the most commonly used respirator, the N95 Filtering Facepiece Respirator (N95), as well as the desire to have added protection while performing aerosol generating procedures (AGPs), dental healthcare personnel (DHCP) have considered alternative respirator options. It is well documented in the medical literature that the Powered Air-Purifying Respirator (PAPR) provides better protection against respiratory pathogens; however, there are no reported cases that describe the use of PAPRs in the dental setting. This survey report evaluates the use of a loose-fitting full facepiece PAPR by different dental providers. OBJECTIVE: To determine if a PAPR can be used in the dental setting and identify any potential barriers to use. METHODS: Eleven DHCP representing general dentistry, dental hygiene, pediatric dentistry, endodontics, orthodontics, oral and maxillofacial surgery and maxillofacial prosthodontics at Walter Reed National Military Medical Center (WRNMMC) and Naval Postgraduate Dental School (NPDS) were asked to wear the MAXAIR PAPR while performing an AGP. They then completed a 14-question survey. RESULTS: There was a 100% response rate. All DHCP with the exception of the endodontist were able to successfully wear the MAXAIR PAPR for the duration of their procedure. All DHCP reported that the PAPR was more comfortable than expected. There were no reports of fogging or hindrance to visibility, breathing was unaffected or enhanced, and the noise level was tolerable. Average time to don and doff the PAPR was 5 minutes. All DHCP were able to wear loupes; some were not able to wear a headlight. Two DHCP reported a history of mild claustrophobia, and both were able to tolerate the PAPR without any issue. 44% preferred the PAPR over the N95. CONCLUSION: This preliminary survey of a loose-fitting PAPR in the dental setting suggests there is a place for PAPRs in the dental community.

Resistance to abrasion of extrinsic porcelain esthetic characterization techniques.

STATEMENT OF PROBLEM: A novel esthetic porcelain characterization technique involves mixing an appropriate amount of ceramic colorants with clear, low-fusing porcelain (LFP), applying the mixture on the external surfaces, and firing the combined components onto the surface of restorations in a porcelain oven. This method may provide better esthetic qualities and toothbrush abrasion resistance compared to the conventional techniques of applying color-corrective porcelain colorants alone, or applying a clear glaze layer over the colorants. However, there is no scientific literature to support this claim. PURPOSE: This research evaluated toothbrush abrasion resistance of a novel porcelain esthetic characterization technique by subjecting specimens to various durations of simulated toothbrush abrasion. The results were compared to those obtained using the conventional characterization techniques of colorant application only or colorant followed by placement of a clear over-glaze. METHOD AND MATERIALS: Four experimental groups, all of which were a leucite reinforced ceramic of E TC1 (Vita A1) shade, were prepared and fired in a porcelain oven according to the manufacturer's instructions. Group S (stain only) was characterized by application of surface colorants to provide a definitive shade of Vita A3.5. Group GS (glaze over stain) was characterized by application of a layer of glaze over the existing colorant layer as used for Group S. Group SL (stain+LFP) was characterized by application of a mixture of colorants and clear low-fusing add-on porcelain to provide a definitive shade of Vita A3.5. Group C (Control) was used as a control without any surface characterization. The 4 groups were subjected to mechanical toothbrushing using a 1:1 water-to-toothpaste solution for a simulated duration of 32 years of clinical use. The amount of wear was measured at time intervals simulating every 4 years of toothbrushing. These parameters were evaluated longitudinally for all groups as well as compared at similar time points among groups. RESULTS: In this study, the novel external characterization technique (stain+LFP: Group SL) did not significantly enhance the wear resistance against toothbrush abrasion. Instead, the average wear of the applied extrinsic porcelain was 2 to 3 times more than Group S (stain only) and Group GS (glaze over stain). Application of a glaze layer over the colorants (Group GS) showed a significant improvement on wear resistance. Despite its superior physical properties, the leucite reinforced ceramic core (Group C) showed 2 to 4 times more wear when compared with other test groups. CONCLUSION: A conventional external esthetic characterization technique of applying a glaze layer over the colorants (Group GS) significantly enhanced the surface wear resistance to toothbrush abrasion when compared with other techniques involving application of colorants only (Group S) or mixture of colorant and LFP (Group SL). The underlying core ceramic had significantly less wear resistance compared with all externally characterized specimens. The novel esthetic characterization technique showed more wear and less color stability, and is thus not advocated as the "best" method for surface characterization. CLINICAL IMPLICATIONS: Application of a glaze layer provides a more wear-resistant surface from toothbrush abrasion when adjusting or extrinsically characterizing leucite reinforced ceramic restorations. Without the glaze layer, the restoration is subjected to a 2 to 4 times faster rate and amount of wear leading to possible shade mismatch.