Effects of steel scalpel, ultrasonic scalpel, CO2 laser, and monopolar and bipolar electrosurgery on wound healing in guinea pig oral mucosa

The effect of biopolymer gel derived from sugarcane on healing of traumatic oral ulcers: an experimental study

PURPOSE

The extracellular polysaccharide (EPS) is produced by the bacterium Zoogloea sp. and plays a positive role in tissue repair. The purpose of this study was to clinically and histologically compare the effects of EPS in the healing of traumatic oral ulcers in rats with the effects of triamcinolone.

METHODS

Ulcers were induced in the oral mucous of 45 male Wistar rats, divided into three groups: control group, treated with triamcinolone, and treated with biopolymer gel. In the clinical evaluation, we considered the weight variation of the animals and the size of the lesion area, at baseline and on treatment days 1, 3 and 7. The histological parameters evaluated were the type and intensity of the inflammatory infiltration, the presence of necrosis and foreign body granuloma and the degree of re-epithelialization of the lesion.

RESULTS

The reduction of the lesion area was greater in the animals treated with EPS, with no difference in the intensity of the inflammatory infiltration between the groups on days 3 and 7 of treatment.

CONCLUSIONS

The results suggest that topical application of EPS in traumatic oral ulcers of rats promotes faster repair than triamcinolone ointment, without increasing the intensity of inflammatory infiltration under the lesion.

Commissurotomy Using Carbon Dioxide Laser in 67 Dogs

Commissurotomy is a surgical technique whereby the lip commissure is incised. Indications for commissurotomy include cheiloplasty, partial commissurectomy, or access to the caudal portion of the maxilla or mandible for oral surgery. Carbon dioxide (CO2) laser was used for commissurotomy in dogs for partial commissurectomy (n = 7) or access for oral surgery (n = 60). All dogs had oral or maxillofacial neoplasms that required resective surgery. The CO2 laser was used to perform commissurotomy or commissurectomy, as indicated. Commissurotomy healing was evaluated at 2 weeks with longer-term follow-up of a minimum of 6 weeks (104.6 ± 99.2 weeks) postoperatively. Postoperative complications related to commissurotomy (n = 6) included mucosal dehiscence (n = 3) less than 1.5 cm, lip margin dehiscence (n = 2) less than 1.0 cm, and complete commissurotomy wound dehiscence (n = 1). Two wound dehiscence cases, including the complete wound dehiscence, had uncomplicated healing following revision surgery. Minor marginal and mucosal dehiscence cases healed by the second intention. Periwound edema ranged from mild to severe and resolved by the 2-week postoperative examination. Statistical analysis showed that complications associated with commissurotomy/commissurectomy were independent of the type of surgical procedure, tumor type, and surgical margin evaluation when using the CO2 laser. Commissurotomy using CO2 laser provided rapid and unimpeded exposure with minimal hemorrhage of the caudal maxilla and mandible for resective oral and maxillofacial surgery.

Injuries of Different Surgical Instruments on the Vocal Folds of Dogs

OBJECTIVE

This study aimed to compare the damage of vocal folds caused by four different surgical instruments: CO2 laser, electrosurgical knife, plasma radiofrequency ablation, and steel knife.

STUDY DESIGN

Randomized controlled study.

METHODS

The CO2 laser, electrosurgical knife, plasma radiofrequency ablation, steel knife, and other instruments were used to simulate the laryngeal microsurgery on experimental dogs. Both total vocal fold resection and punctate ablation were performed. On the day of surgery and 6 days later, the vocal fold tissue from the surgical site was removed for histological evaluation. The extent of vocal fold damage was assessed using the automatic digital pathological scanning system.

RESULTS

We detected varying degrees of damage to the laryngeal tissues. Only the steel knife caused epidermal defects on the vocal fold tissue, while other instruments produced thermal damage of different degrees. Furthermore, the steel knife also showed better and faster healing. The plasma radiofrequency ablation was found to cause more severe thermal burns to vocal folds than other surgical instruments (P < 0.05). Six days postsurgery the inflammatory reaction from the steel knife had basically subsided, with only hyperplasia and tissue repair visible microscopically, showing the best healing degree. On the other hand, the radiofrequency ablation group showed the heaviest inflammatory reaction, indicating relatively poor prognosis (P < 0.05).

CONCLUSION

Compared with the CO2 laser, the electrotome and steel knife showed less damage and better healing, while the plasma radiofrequency ablation showed the most obvious thermal burns to laryngeal and vocal tissues during surgery, with relatively poor healing.

Effects of an Ultra-Polished Scalpel on Incisional Wounds in a Diabetic Model

Inflammation after surgical incisions is related to the degree of tissue damage. Healing with low inflammation is desirable, especially in patients with compromised healing potential. This experimental study was conducted to assess the degree of inflammatory reaction and scar formation from incisions made by an ultra-polished scalpel (UPS). Two paravertebral incisions were made with a conventional scalpel (CS) and a UPS in 18 individual rats with diabetes. The fibrotic tissue (scar) area and expression levels of collagen, transforming growth factor, and matrix metalloproteinases were quantified on postoperative days 3, 7, and 30. The scar widths and areas were significantly lower in the UPS group than in the CS group. The scar widths were 64.3 ± 14.7 µm and 86.8 ± 12.1 µm in the UPS and CS groups, respectively (P = 0.03). The scar areas were 11,398 ± 1595 µm2 in the UPS group and 17,433 ± 3487 µm2 in the CS group (P = 0.014). The UPS group had less inflammation on day 3, less transforming growth factor synthesis on days 3 and 7, lower levels of matrix metalloproteinases, and less collagen synthesis on day 7 than did the CS group. The UPS achieved less local inflammation by reducing the local tissue damage in diabetic rat models, enabling better healing, and resulting in less scar formation. The UPS warrants further clinical study as it may bring beneficial outcomes for patients with impaired healing capability and patients who seek to reduce scarring.

Soy protein/β-chitin sponge-like scaffolds laden with human mesenchymal stromal cells from hair follicle or adipose tissue promote diabetic chronic wound healing

Chronic wounds are a worldwide problem that affect >40 million people every year. The constant inflammatory status accompanied by prolonged bacterial infections reduce patient's quality of life and life expectancy drastically. An important cell type involved in the wound healing process are mesenchymal stromal cells (MSCs) due to their long-term demonstrated immunomodulatory and pro-regenerative capacity. Thus, in this work, we leveraged and compared the therapeutic properties of MSCs derived from both adipose tissue and hair follicle, which we combined with sponge-like scaffolds (SLS) made of valorized soy protein and β-chitin. In this regard, the combination of these cells with biomaterials permitted us to obtain a multifunctional therapy that allowed high cell retention and growing rates while maintaining adequate cell-viability for several days. Furthermore, this combined therapy demonstrated to increase fibroblasts and keratinocytes migration, promote human umbilical vein endothelial cells angiogenesis and protect fibroblasts from highly proteolytic environments. Finally, this combined therapy demonstrated to be highly effective in reducing wound healing time in vivo with only one treatment change during all the experimental procedure, also promoting a more functional and native-like healed skin.

A comparison of radiofrequency Coblation and cold steel excision in the treatment of idiopathic vocal process granulomas

OBJECTIVE

To compare the effectiveness of radiofrequency Coblation assisted excision and cold steel excision in the treatment of idiopathic vocal process granulomas.

METHODS

A retrospective study was performed of patients with idiopathic vocal process granulomas who underwent radiofrequency Coblation excision or cold steel excision between January 2013 and January 2020. The recurrence rate was compared among the two groups at six months post-operatively.

RESULTS

Of the 47 patients with vocal process granulomas, 28 were in the cold steel excision (control) group and 19 were in the Coblation-assisted group. The recurrence rate in the control group was significantly higher than that in the Coblation-assisted group (60.7 per cent vs 5.3 per cent; p < 0.001). In addition, the voice recovery of the Coblation-assisted group was significantly better than that of the control group; vocal quality recovered one month after surgery in the Coblation-assisted group.

CONCLUSION

Radiofrequency Coblation should be considered the optimal method when approaching idiopathic vocal process granulomas surgically.

The Epidermal Keratinocyte as a Therapeutic Target for Management of Diabetic Wounds

Diabetes mellitus (DM) is an important cause of chronic wounds and non-traumatic amputation. The prevalence and number of cases of diabetic mellitus are increasing worldwide. Keratinocytes, the outermost layer of the epidermis, play an important role in wound healing. A high glucose environment may disrupt the physiologic functions of keratinocytes, resulting in prolonged inflammation, impaired proliferation, and the migration of keratinocytes and impaired angiogenesis. This review provides an overview of keratinocyte dysfunctions in a high glucose environment. Effective and safe therapeutic approaches for promoting diabetic wound healing can be developed if molecular mechanisms responsible for keratinocyte dysfunction in high glucose environments are elucidated.

Microenvironment-Based Diabetic Foot Ulcer Nanomedicine

Diabetic foot ulcers (DFU), one of the most serious complications of diabetes, are essentially chronic, nonhealing wounds caused by diabetic neuropathy, vascular disease, and bacterial infection. Given its pathogenesis, the DFU microenvironment is rather complicated and characterized by hyperglycemia, ischemia, hypoxia, hyperinflammation, and persistent infection. However, the current clinical therapies for DFU are dissatisfactory, which drives researchers to turn attention to advanced nanotechnology to address DFU therapeutic bottlenecks. In the last decade, a large number of multifunctional nanosystems based on the microenvironment of DFU have been developed with positive effects in DFU therapy, forming a novel concept of "DFU nanomedicine". However, a systematic overview of DFU nanomedicine is still unavailable in the literature. This review summarizes the microenvironmental characteristics of DFU, presents the main progress of wound healing, and summaries the state-of-the-art therapeutic strategies for DFU. Furthermore, the main challenges and future perspectives in this field are discussed and prospected, aiming to fuel and foster the development of DFU nanomedicines successfully.

Histologic and Immunohistochemical Evaluation of Radiosurgery in Strabismus Surgery in a Rabbit Model

PURPOSE

The aim of this study was to evaluate the use of monopolar radiosurgery (MRS) assisted strabismus surgery and to compare its histologic and immunohistochemical wound healing outcomes with conventional surgery.

MATERIALS AND METHODS

Superior rectus muscle resection was performed on 30 white rabbits with three different surgical muscle cutting techniques: monopolar radiosurgery (MRS group), conventional scissors preceded by bipolar electrocautery (BEC group), and conventional scissors with no cauterization (control group). Degree of tissue injury, bleeding, inflammation, and fibrosis, as well as wound healing rate (CD68+ cell number), were evaluated.

RESULTS

In CS group, hemorrhage scores were significantly higher than those in the other groups (MRS group: Z = 5.182; p < 0.001 and BEC group: Z = 4.463; p < 0.001) and MRS group had lower scores than BEC group; however, the difference was not significant (Z = 1.423; p = 0.211). The tissue injury score in BEC group was higher when compared with MRS, and the difference was statistically significant (p = 0.028). Median inflammation scores at days 1 and 21 were lowest in MRS group, but the difference was not statistically significant among groups (day 1; p = 0.115, day 21; p = 0.095). The median fibrosis score was higher in the control group, when compared with MRS, and the difference was statistically significant (muscle-sclera; p = 0.011 and muscle-conjunctiva: p = 0.003). The macrophage score (number of CD68+ cells) was lowest in CS group; however, the difference was not significant (p = 0.657).

CONCLUSIONS

Monopolar radiosurgery is a novel method for strabismus surgery and provides equivalent hemostasis effects and wound healing properties, compared with conventional methods, and enhances surgeon comfort, as muscle incisions are made in one step with clean surgical area.

Robotic vs. transoral laser surgery of malignant oropharyngeal tumors-what is best for the patient? : A contemporary review

Human papillomavirus (HPV)-associated squamous cell carcinoma of the oropharynx is a malignancy of increasing prevalence. The oncologic community is currently evaluating the safety and efficacy of de-intensifying treatment without compromising oncologic outcomes. Paramount to these treatment algorithms is primary surgery through transoral approaches. This article reviews the literature and concepts pertaining to transoral surgery and describes the two most common techniques, transoral laser microsurgery (TLM) and transoral robotic surgery (TORS).

Radiofrequency ablation of intubation granulomas

OBJECTIVE

We explored the outcomes and voice parameters of patients undergoing plasma radiofrequency (RF) ablation to treat intubation granulomas.

STUDY DESIGN

Prospective case series.

METHODS AND MATERIALS

Patients with intubation granulomas who met the inclusion criteria underwent RF ablation. The complete remission rate and voice function were evaluated preoperatively and at 6 months postoperatively.

RESULTS

We enrolled 13 patients with 25 intubation granulomas. The mean time between intubation and initial diagnosis was 38.6 days and that between intubation and surgical diagnosis was 2.7 months. All 25 granulomas were successfully removed and histologically confirmed. No surgical remnant was evident on the vocal folds and complete glottal closure was observed at 2 weeks postoperatively. No recurrence or RF ablation-related complications were observed during the 6-month follow-up. The complete remission rate was 100% (13/13). In addition, the mean hoarseness, roughness, breathiness, asthenia, and strain (GRBAS) scores, and the maximum phonation time (MPT), improved significantly after treatment (all P < 0.05).

CONCLUSIONS

RF ablation is effective and safe for patients with intubation granulomas who failed medical management or request the procedure. In this study, the complete resolution rate was high and voice restoration outcomes were good.

Risk Factors for Failure of Hard Palate Mucoperiosteal Flap Repair of Acquired Oronasal Communication in Dogs: A Pilot Study

The objective of this retrospective pilot study was to describe potential risk factors for failure of hard palate mucoperiosteal flaps (HPF) transposed for closure of oronasal communication. Dogs (n = 28) with acquired oronasal communication defects were included in the study population. Functional success of an HPF was determined by visual inspection at the last examination and lack of clinical signs. Risk factors for HPF failure including age, sex, body weight, presence of neoplasia at the time of surgery, presence of neoplasia after surgery due to incomplete or narrow margins, use of CO₂ laser, previous surgeries in the same location, HPF blood supply, size of the HPF as a percentage of the total area of the hard palate mucoperiosteum, and distance traveled by the apex of the HPF were evaluated using descriptive statistics and unadjusted logistic regression modeling. Seven out of 28 (25%) hard palate flap procedures resulted in persistent oronasal communication and were considered failures. Body weight (Median: 17 vs. 25 kg, OR = 0.94, 80% CI = 0.90, 0.99), presence of neoplasia at the time of surgery (86 vs. 57%, OR = 4.50, 80% CI = 1.01, 20.06), HPF area (Median: 0.49 vs. 0.41, OR = 84.40, 80% CI = 1.66, 4,298) and apex travel distance (Median: 2.06 vs. 0.67, OR = 5.15, 80% CI = 2.14, 12.38) were associated with flap failure. Within this sample, the presence of neoplasia at the time of initial surgery, increasing the area of the HPF, and distance traveled by the HPF apex were associated with a greater odds of HPF failure. Further studies with larger sample sizes are needed to confirm repeatability of these results. HPFs remain a viable surgical option for closure of oronasal communication. Careful surgical planning, strict adherence to surgical principles, and awareness of anatomical limitations can increase the likelihood of success.

Curcuma longa L. Effects on Akt/mTOR Pathway and NF-κB Expression During Skin Wound Healing: An Immunohistochemical Study

Skin ulcers, wounds, or burns represent a burden for health care worldwide. Our aim was to explore the effects of mucoadhesive formulation with Curcuma longa L. extract mucoadhesive formulation containing curcumin (MFC) on skin healing in Wistar rats. Fifty-four rats were randomly allocated into 3 groups: control, vehicle, and MFC. A full-thickness circular wound was induced on the back of each animal. Two daily applications of the products were performed according to the experimental group. On days 3, 10, and 21, 6 animals in each group were euthanized. Clinical analysis was based on wound area. Histologic analysis was performed in hematoxylin and eosin-stained sections, with re-epithelization and inflammation being assessed by means of semiquantitative scores. To analyze the Akt/mTOR pathway, immunohistochemistry for phospho Akt (pAkt) and phospho ribosomal protein S6 were investigated. In addition, nuclear factor kappa-light-chain-enhancer of activated B cells immunolabeling was performed. Clinical analysis revealed wounds with a smaller area on days 3 and 10 in curcumin-treated animals. Histologically, MFC had a significant impact on inflammatory events on days 3 and 10 and promoted faster re-epithelization, which was evidenced on day 10. MFC-treated wounds exhibited pAkt upregulation on day 10 and both pAkt and phospho ribosomal protein S6 downregulation on day 21. Nuclear factor kappa-light-chain-enhancer of activated B cells expression varied through the evaluation periods; however, no significant difference was observed between groups. Collectively, our results indicate that MFC is efficient in accelerating cutaneous wound repair through modulation of the inflammatory process and stimulus of re-epithelization by an Akt/mTOR-dependent mechanism.

Defocused high-power diode laser accelerates skin repair in a murine model through REDOX state modulation and reepithelization and collagen deposition stimulation

Skin wounds represent a burden in healthcare. Our aim was to investigate for the first time the effects of defocused high-power diode laser (DHPL) on skin healing in an animal experimental model and compare it with gold standard low-level laser therapy. Male Wistar rats were divided into 5 groups: Negative control; Sham; 0.1 W laser (L0.1 W); DHPL Dual 1 W (DHPLD1 W); and DHPL Dual 2 W (DHPLD2 W). Rats were euthanized on days 3, 5, 10, 14 and 21. Clinical, morphological, PicroSirus, oxidative stress (MDA, SOD and GSH) and cytokines (IL-1β, IL-10 and TNF-α) analyses were performed. A faster clinical repair was observed in all laser groups at D10 and D14. DHPLD1 W exhibited lower inflammation and better reepithelization compared to other groups at D10. DHPL protocols modulated oxidative stress by decreasing MDA and increasing SOD and GSH. Collagen maturation was triggered by all protocols tested and L0.1 W modulated cytokines release (IL-1β and TNF-α) at D3. In conclusion, DHPL, especially DHPL1 W protocol, accelerated skin healing by triggering reepithelization and collagen maturation and modulating inflammation and oxidative stress.

Endoscopic Repair of Type 1 Laryngeal Clefts and Deep Interarytenoid Notches: Cold Steel Versus Laser

OBJECTIVES/HYPOTHESIS

Endoscopic repair is the preferred surgical treatment for type 1 laryngeal clefts (T1LCs) and deep interarytenoid notches (DINs). No studies exist showing differences in repair rates using laser and cold steel. Our objective is to assess overall success and revision rate for endoscopic cleft repair and determine whether there is any difference in surgical outcomes between cold steel and laser techniques.

STUDY DESIGN

Retrospective chart review, cohort study.

METHODS

Retrospective review at a quaternary care pediatric hospital. Included all patients who underwent endoscopic repair for T1LCs and DINs between January 2010 and December 2019. Demographics, comorbidities, surgical data, outcomes, and revision status were collected and analyzed. We excluded patients who did not have a follow-up at our institution.

RESULTS

A total of 194 patients were identified, 14 were excluded for lack of follow-up data so 180 were analyzed. Of these, 127 had cold steel repair and 53 had laser repair. There is no significant difference in demographics or comorbidities. In the cold steel group, 4 of 127 (3.1%) had breakdown and in the laser group, 10 of 53 (18.9%) had breakdown. Patients who failed after a cold steel repair tended to break down later (median 12.7 months) when compared to laser repairs (median 2.1 months). Nine of the 10 patients with breakdown after laser repair were noted on initial postoperative evaluation.

CONCLUSIONS

Endoscopic cleft repair is a well-described and effective method for repair of T1LCs and DINs. Both cold steel and laser have high success rates; however, higher failure rates were noted in the laser repair group. Failure after laser repair may occur earlier than failure after cold steel repair. But this did not reach significance.

LEVEL OF EVIDENCE

III Laryngoscope, 2021.

Validation of Ultrasonic Harmonic Scalpel for Real-Time Tissue Identification Using Rapid Evaporative Ionization Mass Spectrometry

In this study, we integrate rapid evaporative ionization mass spectrometry (REIMS) with the Harmonic scalpel, an advanced laparoscopic surgical instrument that utilizes ultrasound energy to dissect and coagulate tissues. It provides unparalleled manipulation capability to surgeons and has superseded traditional electrosurgical tools particularly in abdominal surgery, but is yet to be validated with REIMS. The REIMS platform coupled with the Harmonic device was shown to produce tissue-specific lipid profiles through the analysis of porcine tissues in both negative and positive ionization modes. Comparison with other methods of electrosurgical dissection, such as monopolar electrosurgery and CO₂ laser, showed spectral differences in the profile dependent on the energy device used. The Harmonic device demonstrated major spectral differences in the phospholipid region of m/z 600–1000 compared with the monopolar electrosurgical and CO₂ laser-generated spectra. Within the Harmonic REIMS spectra, high intensities of diglycerides and triglycerides were observed. In contrast, monopolar electrosurgical and laser spectra demonstrated high abundances of glycerophospholipids. The Harmonic scalpel was able to differentiate between the liver, muscle, colon, and small intestine, demonstrating 100% diagnostic accuracy. The validation of the Harmonic device–mass spectrometry combination will allow the platform to be used safely and robustly for real-time in vivo surgical tissue identification in a variety of clinical applications.

Safety and Effectiveness of Copaiba Oleoresin (C. reticulata Ducke) on Inflammation and Tissue Repair of Oral Wounds in Rats

In traditional communities of the Brazilian Amazon, the copaiba oleoresin (C. reticulata Ducke) is widely known for its therapeutic activity, especially its wound healing and anti-inflammatory actions. Our study aimed to evaluate these effects in oral lesions and the safety of the dosage proposed. A punch biopsy wound was induced on the ventral surface of the tongue of forty-five male Wistar rats under anesthesia. Animals were randomly allocated to one of three groups based on the treatment: control, corticoid and copaiba. A daily dose of each treatment and vehicle was administrated by oral gavage for three consecutive days. Sample collections took place on the third, seventh and 15th days post-wounding for clinical and histopathological analyses. Blood was collected on the third and seventh days for kidneys and liver function tests. Semi-quantitative analyses were performed based on scores of inflammation and reepithelization. Tissue collagen deposition was detected by PicroSirius red staining. Copaiba-treated wounds revealed a smaller wound area, decreased of acute inflammatory reaction and enhanced reepithelization. The levels of kidney and liver function tests did not reveal presence of damage post-treatments. Our findings suggest that copaiba oleoresin is a safe and effective alternative therapy for inflammation and tissue repair of oral wounds in this animal model.

How we improve the transoral resection for oral and oropharyngeal cancer: the CO2 waveguide laser

PURPOSE

The main aim of this study was to evaluate the CO₂ waveguide laser (CO₂ WGL) with flexible fiber (Lumenis, Santa Clara, CA) in the treatment of oral and oropharyngeal cancers specifically focusing on the lateral thermal damage (LTD) induced by this instrument and therefore on the reliability of the analysis of frozen sections collected during margin mapping.

METHODS

A total of 48 patients with oral and oropharyngeal cancers from T1 to T4a were prospectively enrolled in the study. We collected data about LTD, pathologic tumor and node stage (pTNM), surgical intervention, kind of reconstruction (no flap, local vs free flap), need for tracheotomy and time of removal, postoperative complications (such as bleeding, mucosal dehiscence, and fistula), need for feeding tube and time of removal.

RESULTS

Mean LTD was 164.7 ± 92.4 μm. Comparing frozen section histology before and after formalin embedding we found 5 true positives, 170 true negatives, 4 false positives and 4 false negatives, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 55.6%, 98%, 55.6%, 98%, and 96.1%, respectively.

CONCLUSION

CO₂ WGL is a very manageable tool, which allows a precise cut. However, its high costs, the inability to re-use the fibers and its low coagulation capability must be considered.

Comparison of Energy-Based Tissue Dissection Techniques in Abdominoplasty: A Randomized, Open-Label Study Including Economic Aspects

BACKGROUND

Abdominoplasty is one of the most common procedures in plastic surgery, and energy-based tissue dissection techniques have become the gold standard. Despite its frequency, abdominoplasty is still associated with high complication rates.

OBJECTIVES

The authors compared clinical and economic data of 4 methods of energy-based tissue dissection in a randomized, open-label study.

METHODS

A total of 57 patients were preoperatively randomized into 4 groups: electrocautery, Ultracision Harmonic Scalpel, argon plasma coagulation, and PEAK-Plasmablade. Demographic and operational data as well as information on the postoperative course and complications were collected. For economic analysis, quotes were obtained from the device companies or official suppliers.

RESULTS

Duration of surgery, drainage quantity, and wound healing complications did not differ significantly between groups. The Ultracision method caused significantly greater blood loss compared with all other techniques (P < 0.01). PEAK and Ultracision devices entailed greater surgical costs compared with APC and electrocautery.

CONCLUSIONS

All methods evaluated can be applied safely and effectively in abdominoplasty procedures. However, these data demonstrate a significantly higher blood loss for the Ultracision Harmonic Scalpel. Considering the clinical data, the higher costs of PEAK and Ultracision methods appear unjustified.

LEVEL OF EVIDENCE: 2

In situ gelation of rhEGF-containing liquid crystalline precursor with good cargo stability and system mechanical properties: a novel delivery system for chronic wounds treatment

The objective of this study was to develop a novel delivery system for recombinant human epidermal growth factor (rhEGF) for chronic wound treatment. Such a delivery system should be of good cargo stability and system mechanical properties in order to guarantee a satisfactory wound-healing effect. rhEGF-containing lyotropic liquid crystalline precursors (rhEGF-LLCPs) with in situ gelation capability were considered as a promising candidate to achieve this aim. Various properties of the optimal formulations (rhEGF-LLCP1 and rhEGF-LLCP2) were characterized, including apparent viscosity, gelation time, in vitro release and phase behavior. The stability of rhEGF and system mechanical properties (i.e. mechanical rigidity and bioadhesive force) were verified. Interestingly, rhEGF-LLCP2 with a larger internal water channel diameter exhibited faster release rate in vitro and then better bioactivity in Balb/c 3T3 and HaCaT cell models. Moreover, rhEGF-LLCP2 showed distinct promotion effects on wound closure, inflammatory recovery and re-epithelization process in Sprague-Dawley rat models. In conclusion, rhEGF-LLCP emerged as a prospective candidate to preserve the stability and enhance the wound-healing effect of rhEGF, which might serve as a new delivery system for chronic wound therapies.

Posterior laryngofissure using a surgical contact diode laser: an experimental feasibility study

To evaluate the feasibility of a 980-nm contact diode laser (CDL) as a method for creating a posterior laryngofissure in live pigs. Twenty-eight Landrace pigs (15-20 kg) were anesthetized, intubated, ventilated, and submitted to a cervical tracheostomy. An anterior and posterior midline longitudinal laryngofissure incision was created according to randomization-control (n = 4), posterior laryngofissure with a scalpel blade; electrocautery (n = 12), posterior laryngofissure by electrocautery (10, 15, 20, 25 W powers); CDL (n = 12), posterior laryngofissure by the CDL (10, 15, 20, 25 W peak powers in pulsed mode). Larynx and proximal trachea were excised, prepared for histopathology, and digital morphometric analysis. Measurements in and within each group were analyzed (Kruskal-Wallis and Dunn test) with a level of significance of p < 0.05. Incision width was not different between the groups, as well as in the powers used in CDL (p = 0.161) and electrocautery group (p = 0.319). The depth of the incisions was smaller in the Laser group compared to control (p = 0.007), and in the electrocautery compared to control (p = 0.026). Incision area was smaller in CDL compared with the control (p = 0.027), and not different between laser and electrocautery groups (p = 0.199). The lateral thermal damage produced by electrocautery was the largest, with a significant difference between laser and electrocautery (p = 0.018), and between electrocautery and control (p = 0.004), whereas the comparison between laser and control showed no significant differences (p = 0.588). The posterior laryngofissure incision using a 980-nm CDL is feasible resulting in smaller incisional area and less lateral thermal damage.

[Papillomatosis of the larynx in children: the current state of the problem]

There is the authors have considered variants of modern methods of medical and surgical treatment of laryngeal papillomatosis in children in the review, based on the etiology of the disease. The analysis of the effectiveness of new methods of combined treatment with the use of modern technologies, taking into account their advantages and disadvantages. The possible prospects for further study problems and develop new methods of adjuvant therapy.

Wound healing after tonsillectomy - a review of the literature

OBJECTIVE

To summarise the available literature related to wound healing post tonsillectomy, including the stages of healing, experimental models for assessing healing (in animals and humans) and the various factors that affect wound healing.

METHODS

A search of the English literature was conducted using the Ovid Medline database, with the search terms 'tonsillectomy' or 'tonsil' and 'wound healing'. Thirty-one articles that objectively assessed tonsillectomy wound healing were included for analysis.

RESULTS

The majority of assessments in humans investigating tonsillectomy wound healing involve serial direct clinical examinations of the oral cavity. Many patient and surgical factors have been shown to affect wound healing after tonsillectomy. There is some research to suggest that the administration of adjunctive treatment in the post-operative period may be beneficial to tonsillectomy wound healing.

CONCLUSION

Wound healing post tonsillectomy has been poorly researched. Having a better understanding of the process of wound healing would allow surgeons to potentially prevent, anticipate and manage complications from the surgery that arise as part of the healing process.

Liquid-Infused Surfaces on Electrosurgical Instruments with Exceptional Antiadhesion and Low-Damage Performances

Electrosurgery based on electrosurgical instruments plays an important role in clinical surgery owing to its advantages of ease of operation, low damage, and less pain to the patient. But soft tissue adhesion on electrosurgical instruments is still a major obstacle to improve the operation efficiency and achieve a better surgical result, regardless of so many developed methods to enhance the antiadhesion performance. In this paper, we successfully demonstrated that liquid-infused surfaces (LISs) can significantly improve the antiadhesion performance of electrosurgical instruments. We developed a microcontact printing method to assist the structure fabrication on the small instrument tip to prepare a firmly liquid-held surface. Soft tissue cutting experiments showed that LIS could not only significantly reduce the adhesion force between the tissue and the instrument tip but also lead to a much smaller charring wound. The underlying mechanism was discussed, and further experiments concluded that LIS have a better duration capability. Our study provides a new insight into the antiadhesion design for electrosurgical instruments.

Is There a Change in the Treatment of T1 Glottic Cancer After CO2 Laser? A Comparative Study with Cold Steel

Objective

Carbon dioxide (CO₂) laser provides high local control and disease-specific survival rates with minor morbidity and good quality of life in transoral cordectomy. We aimed to compare the oncological outcome and survival between cold steel and CO₂ laser in the treatment of early glottic cancer.

Methods

In this retrospective study, the participants were divided into two groups. The first group comprised patients who were operated upon between 2001 and 2007 using cold steel (group 1, n=38), and the second group comprised patients who were operated upon between 2008 and 2016 using CO₂ laser (group 2, n=88). Both groups were compared regarding age, gender, pathological grade, T stage, type of cordectomy, margin status, anterior commissure involvement, follow-up, locoregional recurrence, and disease-free survival (DFS).

Results

The overall survival rate and DFS were similar between the two groups (94.7% vs. 98.9% and 100% vs. 98.9%, respectively), and no association was found between surgical margin positivity and local recurrence. However, a significant association between the presence of anterior commissure involvement and recurrence was found in all 126 patients (p=0.016). Local recurrence was significantly higher in the group 2 (p=0.024), but it did not affect overall survival and DFS in these patients (100% vs. 94.1%).

Conclusion

Although CO₂ laser excision is considered to be superior to cold steel regarding surgical time and bleeding control, the local recurrence rates were found to be higher with the laser than the cold steel. Thus, we argue that cases should be selected more carefully concerning the anterior commissure, depth of tumor invasion lateral to vocal muscle, difficulty at endoscopic exposure for lesions with anterior commissure involvement, and reliability of surgical margins at frozen sections.

Comparing the safety of harmonic ACE and ACE+ around the recurrent laryngeal nerve in swine models

Purpose

Among the various energy-based devices, ultrasonic shears are popular in thyroid surgeries. In this study, we tested the safety of Harmonic ACE and Harmonic ACE+ around the recurrent laryngeal nerve (RLN) in experimental swine models.

Methods

Harmonic ACE and Harmonic ACE+ were each tested in 4 piglets. Harmonic ACE and Harmonic ACE+ were activated at a 0- to 5-mm distance from the RLN. The function of the RLN was assessed using continuous electrophysiological monitoring.

Results

For Harmonic ACE, there was no adverse EMG event found when activated at 4- and 5-mm distances from the RLN. At a 2- to 3-mm distance, there were 4 adverse EMG events observed. In these 4 cases, adjacent tissue shrinkage occurred after 6 to 15 seconds of activation, and the RLN touched the Harmonic ACE. At a 1-mm distance, there were 2 adverse EMG events found after 25 seconds of activation. For Harmonic ACE+, there was no adverse EMG event observed when activated at 1- and 3-mm distances from the RLN. At a 0-mm distance, 2 adverse EMG events occurred after 6 to 10 seconds of activation.

Conclusion

The safe distance of Harmonic ACE and ACE+ was 4 and 1 mm, respectively, in the swine models. Harmonic ACE+ is safer than Harmonic ACE because it did not cause any tissue shrinkage. Surgeons need to understand the characteristics of devices for safe operation.

Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A typical anti-wetting superhydrophobic surface easily fails when exposed to a high-temperature liquid. Recently, Nepenthes-inspired slippery surfaces demonstrated a new way to solve the adhesion problem. A lubricant layer on the slippery surface can act as a barrier between the repelled materials and the surface structure. However, the slippery surfaces in previous studies rarely showed high-temperature resistance. Here, we describe a protocol for the preparation of slippery surfaces with high-temperature resistance. A photolithography-assisted method was used to fabricate pillar structures on stainless steel. By functionalizing the surface with saline, a slippery surface was prepared by adding silicone oil. The prepared slippery surface maintained the anti-wetting property for water, even when the surface was heated to 300 °C. Also, the slippery surface exhibited great anti-adhesion effects on soft tissues at high temperatures. This type of slippery surface on stainless steel has applications in medical devices, mechanical equipment, etc.

Comparative study on the incision healing of the palatal mucosa by using Er:YAG laser or traditional scalpel in the SD rats

The aim of this study was to compare the histology of wound healing following incisions with the scalpel or the Er:YAG laser in the palatal mucosa of SD rats. Two types of wounds were performed with the stainless steel scalpel or the Er:YAG laser in the palatal mucosa of SD rats, while the adjacent untreated palatal mucosa was chosen as control. Rats were sacrificed on day 1, day 3, day 7, and day 30 post-surgery. Biopsy samples from each wound were examined and the expression of IL-1ß and TGF-ß1 was determined by enzyme-linked immunosorbent assay (ELISA). The early postoperative incision of the scalpel group had obvious bleeding and swelling, while the laser wound mainly covered the surface of white pseudomembrane. The infiltration of neutrophils and lymphocytes in the stroma of the scalpel incision was more than that of the laser group. Compared to the laser group, 1 and 3 days after operation, the TGF-β1 content of the scalpel group were significantly increased (P = 0.032 and 0.019). Seven days after operation, the TGF-β1 content of two groups was decreased. TGF-β1 expression of control group was obviously increased (P > 0.05); 1, 3, and 7 days after operation, the traditional scalpel amount of IL-1β expression was significantly higher than that of control group (P = 0.000, 0.000, and 0.001). Postoperative day 1, IL-1β expression of laser group and control group had no significant difference (P = 0.572). Three days after operation, IL-1β expression of laser incision was increased and was significantly higher than that in control group (P = 0.032), however lower than the scalpel group (P = 0.03). Seven days after operation, the IL-1β expression of two groups had no significant difference (P = 0.333); however, the IL-1β expression of two groups were significantly higher than that of the control group (P = 0.02 and 0.001). Compared to the traditional scalpel, the incision of Er:YAG laser has smaller inflammation reaction, more pseudomembrane coverage, and minimal damage of the mucoperiosteal tissue.

Terminal Deoxynucleotidyl Transferase-Mediated Deoxyuridine Triphosphate Nick End Labeling (TUNEL) Assay to Characterize Histopathologic Changes Following Thermal Injury

Background

Despite the wide application of lasers and radiofrequency (RF) surgery in dermatology, it is difficult to find studies showing the extent of damage dependent on cell death.

Objective

We evaluated histopathologic changes following in vivo thermal damage generated by CO₂ laser, 1,444 nm long-pulsed neodymium:yttrium-aluminum-garnet (LP Nd:YAG) laser and RF emitting electrosurgical unit.

Methods

Thermal damage was induced by the above instruments on ventral skin of rat. Specimens were stained with hematoxylin and eosin, along with a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay, to highlight the degree of irreversible cellular injury.

Results

The volume of vaporization was largest with the CO₂ laser. Area of cell death area identified by TUNEL assay, when arranged from widest to narrowest, was 1,444 nm LP Nd:YAG laser, CO₂ laser, and RF emitting electrosurgical unit.

Conclusion

This histopathologic evaluation of the acute characterization of injury across devices may be advantageous for attaining better treatment outcomes.

Enhanced electroscalpel incisional wound healing potential of honey in wistar rats

Electrosurgery reduces surgical bleeding, and delayed wound healing. This study evaluated comparative incisional wound healing potential of honey in wound created with electroscalpel and cold scalpel. The study used twelve (12) adult male albino rats (130 ± 20 g), randomly grouped into Electro-cautery (n = 6) and Cold scalpel (n = 6). Each rat had three full thickness (6 mm diameter) skin wounds (a, b and c) created on its dorsum with either Electroscalpel (ES) or Cold blade scalpel (CS), and treated topically with Silver sulphadiazine (SSD, wound a), untreated (control, wound b) and Bee honey (H, wound c). The wounds were evaluated for gross (exudation, edema, hyperemia, contraction), histologic (granulation, angiogenesis, fibroplasia, epithelialization) and immunologic healing indices using standard techniques. Data were analyzed with Chi-square, Two-way Analysis of Variance (ANOVA) and Duncan Multiple Range tests (DMRT) at α = 0.05. Wound hyperemia and edge edema were prominent in the ES group from day 4 to 6 (P = .000). Percentage wound contraction was higher in the CS than ES group from days 5 to 7 (P = .006) and in the CS treated with honey than ES treated with honey from days 7 to 14 (P = .000). Granulation tissue reduced in ES group treated with SSD than in honey and control wounds. Fibroelastic tissue increased in SSD and honey treated wounds of ES group, and higher in honey treated wounds of CS group (P < .05). Fibroplasia was sustained in honey and SSD treated wounds than control. Honey can be applied to electroscalpel surgical wound to facilitate rapid healing during surgical management of tumours having vascular network.

Preparation and in vivo evaluation of a novel gel-based wound dressing using arginine–alginate surface-modified chitosan nanofibers

The development of an effective wound dressing with the ability to induce skin wound healing is a great challenge in medicine. Nanofibers are highly attractive for wound dressing preparation due to their properties such as hemostasis induction, good absorption of wound exudates, and facilitation of cell growth. Chitosan nanofibers have attracted great attention for application in wound dressings due to their accelerating effects on wound healing. In this study, arginine surface-modified chitosan nanofibers were successfully prepared by attachment of arginine molecules on the surface of chitosan nanofibers using sodium alginate through electrostatic interaction. The effect of pH on the amount of attached arginine was evaluated at three different pH values; 5, 6, and 7. Fourier-transform infrared spectroscopy and zeta potential of chitosan nanofibers before and after surface modification suggested the occurrence of the attachment of arginine to chitosan nanofibers. Scanning electron microscope images showed the nanofibrous structure of arginine surface-modified chitosan nanofibers with an average diameter ranging from 100 nm to 150 nm. The release of arginine from arginine surface-modified chitosan nanofibers gel showed a sustained release manner. The suitable viscosity and spreadability of arginine surface-modified chitosan nanofibers gel verified its easy application at the wound site. Arginine surface-modified chitosan nanofibers gel significantly improved the wound healing process including wound closure when tested in vivo using rat model. Additionally, histological examination and immunohistochemical studies showed the significant enhancement of the re-epithelialization, collagen deposition, and angiogenesis in the skin of the animal group treated with arginine surface-modified chitosan nanofibers gel compared with the other control groups. These results suggested that arginine surface-modified chitosan nanofibers gel could be introduced as an effective wound dressing.

Periodontal and peri-implant wound healing following laser therapy

Laser irradiation has numerous favorable characteristics, such as ablation or vaporization, hemostasis, biostimulation (photobiomodulation) and microbial inhibition and destruction, which induce various beneficial therapeutic effects and biological responses. Therefore, the use of lasers is considered effective and suitable for treating a variety of inflammatory and infectious oral conditions. The CO2 , neodymium-doped yttrium-aluminium-garnet (Nd:YAG) and diode lasers have mainly been used for periodontal soft-tissue management. With development of the erbium-doped yttrium-aluminium-garnet (Er:YAG) and erbium, chromium-doped yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers, which can be applied not only on soft tissues but also on dental hard tissues, the application of lasers dramatically expanded from periodontal soft-tissue management to hard-tissue treatment. Currently, various periodontal tissues (such as gingiva, tooth roots and bone tissue), as well as titanium implant surfaces, can be treated with lasers, and a variety of dental laser systems are being employed for the management of periodontal and peri-implant diseases. In periodontics, mechanical therapy has conventionally been the mainstream of treatment; however, complete bacterial eradication and/or optimal wound healing may not be necessarily achieved with conventional mechanical therapy alone. Consequently, in addition to chemotherapy consisting of antibiotics and anti-inflammatory agents, phototherapy using lasers and light-emitting diodes has been gradually integrated with mechanical therapy to enhance subsequent wound healing by achieving thorough debridement, decontamination and tissue stimulation. With increasing evidence of benefits, therapies with low- and high-level lasers play an important role in wound healing/tissue regeneration in the treatment of periodontal and peri-implant diseases. This article discusses the outcomes of laser therapy in soft-tissue management, periodontal nonsurgical and surgical treatment, osseous surgery and peri-implant treatment, focusing on postoperative wound healing of periodontal and peri-implant tissues, based on scientific evidence from currently available basic and clinical studies, as well as on case reports.

Diathermy versus scalpel in transverse abdominal incision in women undergoing repeated cesarean section: A randomized controlled trial

AIM

The aim of this study was to evaluate the volume of blood loss, wound incision time and wound complication according to use of scalpel or electrosurgery during the creation of transverse abdominal incisions during repeated cesarean section (CS).

MATERIAL AND METHODS

A randomized controlled trial was carried out at Ain Shams University Maternity Hospital. We recruited 130 women with a history of one previous CS at the time of their planned lower-segment CS. Participants were randomized to anterior abdominal wall opening from subcutaneous tissue till the peritoneum by either the use of scalpel with disposable blade (No. 22) or diathermy using the standard diathermy pen electrode. The main outcome measures were the volume of blood loss from skin incision to the end of the peritoneal incision, the operative time and wound complication.

RESULTS

We observed a highly significant difference between the two groups in blood loss (median [interquartile range], 11 [8-15.25] g for the diathermy group vs 20 [18-23] g for the scalpel group, P < 0.001) and skin-to-peritoneum incision time (median [interquartile range], 7 [5-7.25] min for the diathermy group vs 10 [7-11] min for the scalpel group, P < 0.001). The postoperative pain was less in the diathermy group but wound complications showed no statistical difference.

CONCLUSION

The use of diathermy in the opening of anterior abdominal wall during CS decreases blood loss and operative time but has no impact on postoperative pain or wound complications.

Comparison of Radiofrequency and Electrocautery With Conventional Scalpel Incisions

PURPOSE

The disadvantages of conventional scalpels, including insufficient control of bleeding, prompted us to search for new alternative methods such as electrosurgery and radiosurgery. In this study, the conventional scalpel was compared with radiosurgery and electrosurgery for wound healing with assessment of lateral heat production, inflammation, and instrument performance.

MATERIALS AND METHODS

Incisions were made in the palatal mucosa of 42 Wistar rats using a scalpel, electrocautery instrument, or radiofrequency instrument. Postoperative hemostasis, tissue coagulation, and tissue sticking were measured, and pain evaluation through weight loss was recorded. Gingival biopsy specimens from the surgical area were obtained at the time of surgery and 2, 4, 7, and 14 days postoperatively and were evaluated immunohistochemically for inducible nitric oxide synthase and heat shock protein 70. Kruskal-Wallis, 1-way analysis of variance, and Mann-Whitney U tests were used for statistical evaluation.

RESULTS

The rats in the electrosurgery and radiosurgery groups had aggressively greater weight loss when compared with the scalpel group in the first 7 days. Hemostasis was better in the electrocautery group, tissue coagulation was greater in the radiofrequency group (P < .001), and tissue sticking was lesser in the scalpel group (P < .001) compared with the other groups. Inducible nitric oxide synthase expression and heat shock protein 70 expression were similar in all 3 groups.

CONCLUSIONS

Electrosurgery performed better regarding hemostasis, whereas a scalpel was superior in terms of tissue sticking and tissue coagulation. Radiosurgery was superior regarding hemostasis when compared with a conventional scalpel, but it was not as successful as electrosurgery.

Clinical-pathological study of the healing of wounds provoked on the dorso-lingual mucosa in 186 albino rats

OBJECTIVE: To evaluate wound healing of incisions created in the upper aerodigestive tract.

STUDY DESIGN AND SETTING: In this prospective and blind study, 186 adult rats were assigned to six groups to create incisions in the tongue. In the first three groups, the wounds were made with a steel scalpel; no substance was applied to the wound in the first group, but N-butyl-2-cyanoacrylate was applied in the second group, and trichloroacetic acid at 50 percent in the third group. In the fourth, fifth, and sixth groups, the wounds were caused by cryosurgery, electrocautery, and CO2 laser. Hemostasis, postoperative oral intake, and wound healing were measured. Statistical analysis was performed with analysis of variance.

RESULTS: The wounds to which N-butyl-2-cyanoacrylate was applied showed no hemorrhaging and faster reepithelialization and resolution of the inflammatory response.

CONCLUSIONS: N-butyl-2-cyanoacrylate is a good hemo-static for managing wounds in the oral mucosa provoked by steel scalpel.

© 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Comparative study of acute tissue damage induced by the CO2 laser versus microelectrodes in cordectomies

OBJECTIVE:

This study compared the acute tissue damage produced by a CO2 laser and microelectrodes in samples of vocal cords from patients undergoing laryngeal endoscopic surgery for stage T1 squamous cell carcinoma.

STUDY DESIGN AND SETTING:

Based on prior surgical experience with the CO2 laser and microelectrodes, the study protocol used hematoxylin-eosin staining of vocal cords treated with a CO2 laser (n = 20) or microelectrode (n = 20).

RESULTS AND CONCLUSION:

The acute tissue damage produced by the CO2 laser was similar to that induced by microelectrodes in cutting mode. The tissue damage resulting from the use of the microelectrode in coagulation mode was comparatively greater.

LL37 loaded nanostructured lipid carriers (NLC): A new strategy for the topical treatment of chronic wounds

The LL37 is a human antimicrobial peptide which not only has a broad spectrum of antimicrobial activity, but it has also been proved to modulate wound healing by participating in angiogenesis, epithelial cell migration and proliferation, and immune response. In this work, LL37 has been encapsulated in nanostructured lipid carriers (NLCs), produced by the melt-emulsification method, in order to improve its effectiveness. The characterisation of the NLC-LL37 showed a mean size of 270nm, a zeta potential of -26mV and an encapsulation efficiency of 96.4%. The cytotoxicity assay performed in Human Foreskin Fibroblasts demonstrated that the NLC-LL37 did not affect cell viability. Moreover, the in vitro bioactivityassay evidenced that the peptide remained active after the encapsulation, since the NLC-LL37 reversed the activation of the macrophages induced by LPS in the same way as the LL37 in solution. In addition, the in vitro antimicrobial assay revealed the NLC-LL37 activity against Escherichia coli. The effectiveness of the nanoparticles was assessed in a full thickness wound model indb/dbmice. The data demonstrated that NLC-LL37 significantly improved healing compared to the same concentration of the LL37 solution in terms of wound closure, reepithelisation grade and restoration of the inflammatory process. Overall, these findings suggest a promising potential of the NLC-LL37 formulation for chronic wound healing.

Healing process following laser cordectomy of early glottis carcinoma from endoscopic view

BACKGROUND AND OBJECTIVE

Transoral laser surgery is useful for treating early glottic carcinoma. Wound areas after carbon dioxide (CO2 ) laser surgery are not covered by flaps, delaying healing. The healing process following laser cordectomy is not well understood. In this study, laryngoscopes were used to monitor the normal healing process after laser cordectomy and to determine if there was residual or recurrent disease.

MATERIALS AND METHODS

This prospective case study included 36 patients who underwent CO2 laser surgery for early glottis carcinoma between January 2011 and June 2014 at a university tertiary referral center. Postoperative complications, oncologic results, and mucosal stabilization time were analyzed. Vocal fold stabilization was defined as an absence of gross changes during two consecutive follow-up examinations.

RESULTS

The 3-year overall survival rate was 100% and the 3-year local control rate was 94%. Vocal cord stabilization was observed in 29 patients at a mean 88.1 days, with stabilization associated with the type of cordectomy (P < 0.05). During the wound-healing process, two patients experienced local recurrences. One had a persistent white patch for over 4 months and the other presented with a new mass in a non-operated area. Biopsies of both lesions showed recurrent disease. Postoperative complications included granulation in two patients and anterior commissure adhesion in one.

CONCLUSION

CO2 laser microsurgery is an effective treatment for early glottis carcinoma. Close attention should be paid to delays in healing process after laser surgery. Interventions should be considered for patients with abnormal laryngoscopic appearance or overly prolonged healing. Lasers Surg. Med. 48:483-489, 2016. © 2016 Wiley Periodicals, Inc.

Four different diode lasers comparison on soft tissues surgery: a preliminary ex vivo study

Objectives: The introduction of diode lasers in dentistry had several advantages, principally consisting on the reduced size, reduced cost and possibility to beam delivering by optical fibbers. Up today only the wavelengths around 810 and 980 nm were the most utilized in oral surgery but recently more different lasers had been proposed. The aim of this study was to compare the efficacy of four diode laser wavelengths (810, 980, 1470 and 1950 nm) for the ablation of soft tissues. Material and methods: Specimens were surgically collected from the dorsal surface of four bovine tongues and irradiated by four different diode wavelengths. Thermal increase was measured by two thermocouples, the first at a depth of 0.5 mm, and the second at a depth of 2 mm. Initial and final surface temperatures were recorded by IR thermometer. Epithelial changes, connective tissue modifications, presence of vascular modification and incision morphology were histologically evaluated by two blind pathologists. Results: The time necessary to perform the excision varied between 271 seconds (808 nm, 2W) and 112 seconds (1950 nm, 4W). Temperature increase superficial level varied from 16.3° (980 nm, 4W) and 9.2° (1950 nm, 2 W). The most significant deep temperature increase was recorded by 980 nm, 4 W (17.3°) and the lowest by 1950 nm, 2 W (9.7°). The width of epithelial tissue injuries varied between 74 pm from 1950 nm diode laser at 2 W to 540 pm for 1470 nm diode laser at 4 W. Conclusion: The quality of incision was better and the width of overall tissue injuries was minor in the specimens obtained with higher wavelength (1950 nm) at lower power (2W).

Neurofibromas of the Oral Cavity: Clinical Aspects, Treatment, and Outcome

OBJECTIVE

This study aimed to evaluate the efficacy of diode laser for the surgical treatment of neurofibromas (NF), in terms of clinical outcome and therapeutic success.

BACKGROUND DATA

The NF is a benign tumor of the peripheral nerve sheath, characterized by the proliferation of Schwann cells, perineural cells, and endoneural fibroblasts. NF may occur as a solitary lesion, or as part of a generalized neurofibromatosis syndrome; much more rarely it occurs in the form of multiple neurofibromas with no associated syndrome. Two distinct variants of neurofibromatosis have been described: types I and II.

METHODS

Ten cases are reported (6 women and 4 men, age range 43-70 years) with smooth, painful, or painless lesions of the oral mucosa. Lesions were completely excised using a diode laser at 980 nm wavelength, average power 2.0 W, in continuous wave mode, with 320 μm optical fibers, for 45 sec average time.

RESULTS

Complete healing occurred within 20 days. There were no adverse effects; patients were carefully followed up and there have been no recurrences after an interval of 3 months to 3 years.

CONCLUSIONS

The results of this diode laser treatment of NF demonstrate good effectiveness of this novel therapy, which may replace conventional surgical procedures.