Can Low-Level Laser and Light-Emitting Diode Enhance the Stability of Dental Implants?

PURPOSE: Stability of dental implants is an important factor for evaluation of osseointegration. The aim of this study was to evaluate the effect of combined use of low-level laser (LLL) and light-emitting diode (LED) therapy on the stability of dental implants during the healing phase. MATERIALS AND METHODS: This was a randomized clinical trial. Patients were assigned to two groups: In group 1, patients received LLL and LED 20 min/day for 10 days after implant insertion. Patients in group 2 (controls) did not undergo LLL and LED. The implant stability quotient (ISQ) was measured at 0 (time 0), 10 (time 1), 21 (time 2), 42 (time 3) and 63 days (time 4) after implant placement. Independent t test was used to compare the ISQs between the two groups. RESULTS: Fifty-eight patients were studied in two groups (n = 28). The mean ISQ did not differ immediately after insertion (P > 0.05). The mean ISQ differed significantly between the two groups on days 10, 21, 42 and 63 (P < 0.05). Results demonstrated an increase in the amount of ISQ in group 1 (intervention) at times 1, 2, 3 and 4. In the control group, the amount of ISQ decreased on days 10 and 21 following implant insertion, but increased afterward on days 42 and 63. CONCLUSION: The results of this study showed that simultaneous use of LLL and LED increased the stability of the implants after 9 weeks of follow-up.

A Novel Laryngeal Palpatory Scale (LPS) in Patients with Muscle Tension Dysphonia.

OBJECTIVES: Laryngeal palpation is a routine clinical method for evaluation of patients with muscle tension dysphonia (MTD). The aim of this study was to develop a new comprehensive valid and reliable "laryngeal palpatory scale" (LPS), based on psychometric criteria. METHODS: The scale items were selected based on an in-depth analysis of the literature and an expert focus group. Scale item generation and item reduction were followed by a psychometric assessment. Qualitative and quantitative content validity (the content validity ratio (CVR), content validity index (CVI)), the qualitative face validity, and the inter-rater reliability were determined. For this purpose, 531 patients were assessed and finally 55 patients with primary MTD (26 women, mean age: 40.8 years, SD: 12.5; 29 male, mean age: 41.6 years, SD: 11.8) participated in the study. A weighted kappa (k*) statistic was used to examine the inter-rater reliability for each single item. RESULTS: Based on the CVR, three items were omitted because they had a score of less than 0.62. The CVI for all remaining items was greater than 0.79 and the scale CVI was equal to 0.96. The final 45 items were a result of the study. The inter-rater reliability for each single item ranged from 0.41 to 1, indicating moderate to almost perfect agreement. CONCLUSIONS: The LPS is a reliable and valid instrument for assessing patients with MTD. However, future studies are needed to provide adequate data on sensitivity, specificity, concurrent validity, and cutoff scores.

The Design and Assessment of a Multiparametric Model for the Dysphonia Severity Index for Persian-speaking Populations.

OBJECTIVES: In instrumental voice assessment, multiparametric models reflect the multidimensional nature of voice and are therefore better than models that reflect only a single dimension of voice. The Dysphonia Severity Index (DSI) is one of the most common multiparametric models. In voice assessment, race, language, and structural and physiological features affect the acoustic, aerodynamic, and voice range profile measures. Given these differences, this study was conducted to design and evaluate a multiparametric and objective model for assessing the severity of dysphonia in Persian-speaking populations. MATERIAL AND METHODS: This study examined 300 participants with several types of dysphonia (104 women and 196 men) and 100 healthy individuals (63 women and 37 men). Five acoustic parameters, three aerodynamic parameters, and seven voice range profile parameters were measured for designing the model. Perceptual evaluation was performed using the grade, roughness, breathiness, asthenia, strain scale. The logistic regression analysis was used to determine the factors affecting the DSI and each component's coefficient. RESULTS: Of the 15 parameters assessed, shimmer, vital capacity, semitone range, and voice onset time of /pa/ remained in the model with their coefficients. This section presents the DSI model for the examined population. The discriminant analysis showed that this combination corresponds to 47.8 of the perceptual assessment: DSI = 0.289 (shimmer) + 0.0001 (VC) - 0.059 (STR) - 13.278 (VOT_Pa). CONCLUSION: In this study, the DSI corresponded to the physiological, linguistic, and racial characteristics of the Persian-speaking population with or without voice disorder.

The Relationship Between the Aerodynamic Parameters of Voice and Perceptual Evaluation in the Iranian Population With or Without Voice Disorders.

OBJECTIVES: Aerodynamic evaluations can provide useful information about the interaction between the respiratory and the phonation systems. The present study was conducted to investigate the relationship of maximum phonation time (MPT), vital capacity (VC), and phonation quotient (PQ) with perceptual evaluation in different types of dysphonia. The relationship between these parameters and the type of dysphonia was also examined. MATERIALS AND METHODS: The study participants consisted of 300 individuals with different types of dysphonia (104 women and 196 men) and 100 healthy samples (63 women and 37 men). A professional speech-language pathologist conducted the perceptual evaluation based on the G (grade) component of the GRBAS scale, which stands for grade, roughness, breathiness, asthenia, and strain. VC was measured using a spirometer and MPT using a stopwatch. PQ was calculated as the ratio of VC to MPT. RESULTS: The difference between the mean ± standard deviation of PQ, VC, and MPT were found to be significant at all the four degrees of dysphonia severity (P < 0.001). There was a significant difference in mean MPT and VC between the genders (P < 0.001), but no significant gender differences were observed in terms of the mean PQ (P = 0.346). The study participants were classified into four groups, including the organic dysphonia group, neurologic dysphonia and functional dysphonia groups, and the normal group; the study variables measured were found to be significantly different between all the four groups (P < 0.001). CONCLUSION: As MPT and PQ were correlated with the perceptual G (grade) and differentiated dysphonic from healthy individuals, clinicians are recommended to take account of them in their instrumental evaluations.

Objective Voice Analysis of Pediatric Cochlear Implant Recipients and Comparison With Hearing Aids Users and Hearing Controls.

OBJECTIVES: Phonation is influenced by hearing as a feedback mechanism. The purpose of the present study was to compare selected acoustic parameters in children using cochlear implants (CIs), those using hearing aids (HA), and their normal-hearing (NH) peers. METHODS: The participants were 15 children using CI (mean age: 72 months), 15 children using HA (mean age: 74 months), and 15 NH children (mean age: 77 months). The vowel /a/ was produced to measure perturbation and mean fundamental frequency. The six Persian vowels in /CbVCd/ were obtained to extract vowel duration. Data were analyzed by one-way analysis of variance. RESULTS: Results revealed a statistically significant difference between the NH group and the HA group regarding fundamental frequency (F2,51 = 3.443, P < 0.05), jitter local (F2,51 = 1.629, P < 0.05), jitter local absolute (F2,51 = 6.519, P < 0.001), jitter rap (F2,51 = 7.151, P < 0.001), jitter ppq5 (F2,51 = 5.894, P < 0.001), shimmer local (%) (F2,51 = 8.070, P < 0.001), shimmer local (dB) (F2,51 = 3.884, P < 0.05), shimmer apq3 (F2,51 = 4.926, P < 0.05), shimmer apq5 (F2,51 = 8.442, P < 0.001), and harmonic-to-noise ratio (F2,51 = 4.117, P < 0.001). The mean values of the duration of all six vowels were significantly greater in children with CI and HA than in NH children (P < 0.001). CONCLUSION: It seems that after 8 months of using CI, auditory control of voice production would be enabled. Furthermore, children with hearing impairment potentially regard vowel sound duration as a distinguishing feature, whereas in NH speakers, the duration has the least effect in vowel identification.

A Cepstral Analysis of Normal and Pathologic Voice Qualities in Iranian Adults: A Comparative Study.

INTRODUCTION: The use of frequency-based analysis as an accurate method of voice analysis motivated us to evaluate the voice qualities of healthy versus dysphonic Iranian people. METHODS: Two hundred normal and dysphonic participants aged between 20 and 50 years in either gender were divided into four different equal groups. For the tasks, 5-second prolongation of vowel /a/ and a sample of reading text were used for the analysis. "Speech Tool" software was employed for Cepstral peak prominence (CPP) and cepstral peak prominence-smoothed (CPPS) analyses. The t test and Mann-Whitney U test were used for statistical analysis. RESULTS: Significant differences between the dysphonic and controls were discovered based on CPP and CPPS in the reading tasks (males and females) and CPPS in the sustained vowel (males and females). Nevertheless, the two male groups showed no differences in the sustained vowel in CPP. Moreover, significantly lower CPP and CPPS were observed in the sustained vowel and reading tasks for the dysphonic females compared to the control group and either group of males. DISCUSSION AND CONCLUSION: In spite of the different characteristics of consonant-vowel contexts in Persian language, the results of this study suggested that both CPP and CPPS are appropriate to differentiate between normal and dysphonic voices in connected speech and CPPS is promising for sustained phonation in Persian. The results of this research also suggested that the male group in the normal and dysphonic samples had better CPP and CPPS values.

Vocal Function Exercises for Muscle Tension Dysphonia: Auditory-Perceptual Evaluation and Self-Assessment Rating.

OBJECTIVE: Muscle tension dysphonia (MTD) is a functional dysphonia, which appears with an excessive tension in the intrinsic and extrinsic laryngeal musculatures. MTD can affect voice quality and quality of life. The purpose of the present study was to assess the effectiveness of vocal function exercises (VFEs) on perceptual and self-assessment ratings in a group of 15 subjects with MTD. METHODS: The study comprised 15 subjects with MTD (8 men and 7 women, mean age 39.8 years, standard deviation 10.6, age range 24-62 years). All participants were native Persian speakers who underwent a 6-week course of VFEs. The Voice Handicap Index (VHI) (the self-assessment scale) and Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) scale (perceptual rating of voice quality) were used to compare pre- and post-VFEs. RESULTS: GRBAS data of patients before and after VFEs were compared using Wilcoxon signed-rank test, and VHI data of patients pre- and post-VFEs were compared using Student paired t test. These perceptual parameters showed a statistically significant improvement in subjects with MTD after voice therapy (significant at P < 0.05 (*) and P < 0.004 (**)). Also results indicated statistically noticeable reduction in the mean VHI scores across subjects with MTD (significant at P < 0.05 (*) and P < 0.004 (**)). CONCLUSIONS: Significant improvement after therapy for participants has been observed by the aid of auditory-perceptual ratings of voice quality (with the GRBAS scale) and the patient's self-assessment ratings measurements (with the VHI). As a result, the data provide evidence regarding the efficacy of VFEs in the treatment of patients with MTD.

An Island Flap Technique for Laryngeal Intracordal Mucous Retention Cysts.

INTRODUCTION: Mucous retention cysts are a subtype of intracordal vocal cysts that may occur spontaneously or may be associated with poor vocal hygiene, and which require optimal treatment. The objective of this study was to present a new laser-assisted microsurgery technique for treating intracordal mucous retention cysts and to describe the final outcomes. MATERIALS AND METHODS: In this prospective study, we assessed the pre-operative and post-operative acoustic analysis, maximum phonation time (MPT), and voice handicap index (VHI) of four patients with a diagnosis of mucous retention cyst. The island flap technique was applied to all patients without any complications. In this procedure, we favored the super-pulse mode using a 2-W power CO2 laser to remove the medial wall of the cyst, before clearing away the lateral wall margins of the cyst using repeat-pulse mode and a 2-W power CO2 laser. Indeed, we maintained the underlying epithelium and lamina propria, including the island flap attached to the vocal ligament. RESULTS: There was a statistically significant improvement in the MPT (pre-op,11.05 s; post-op,15.85 s; P=0.002) and the VHI (pre-operative, 72/120; post-operative,27/120; P=0.001) in all patients. Moreover, jitter and shimmer were refined after surgery, but there was no statistically significant relationship between pre-operative and post-operative data (P=0.071) (P=0.622). In the follow-up period (median, 150 days), there was no report of recurrence or mucosal stiffness. CONCLUSION: The island flap procedure in association with CO2 laser microsurgery appears to be a safe and effective treatment option for intracordal mucous retention cysts, but needs further investigation to allow comparison with other methods.

Laryngeal manual therapy as a treatment for impaired production of tahrir vibrato in traditional Iranian singers.

BACKGROUND: Iranian vibrato (tahrir) is a common feature of traditional Iranian singing. A unique feature of tahrir is a modulated voice quality perceived as a rhythmic falsetto voice break associated with upward pitch inflections. Laryngeal discomfort and impaired voice quality can occur in singers when they perform Iranian tahrir using an improper technique. AIM: A case series research design was used to explore voice treatment outcomes using laryngeal manual therapy (LMT) for treating voice problems associated with tahrir singing. METHOD: Four professional Iranian singers of the traditional style (3 men and 1 woman) were studied. All subjects reported difficulty executing tahrir during performances. They were assessed by a speech-language pathologist (SLP) specializing in the administration of LMT for voice disorders. Multidimensional assessments were made of the participants' vocal function using acoustic and auditory-perceptual evaluation, self-reports of the singers, and LMT assessments by the SLP before and after treatment. The therapeutic program implemented LMT techniques to release laryngeal joints and reduce muscular tension. RESULTS: Pretreatment examination of the larynx and anterior neck musculature using palpation showed that the difficulties in producing tahrir vibrato were associated with a decreased thyrohyoid space and tension in the submental complex and sternocleidomastoid. Posttreatment examination showed an increased thyrohyoid space and reduced tension in the submental complex and sternocleidomastoid, associated with the singers' perception of reduced effort producing tahrir vibrato during singing. CONCLUSION: Tahrir vibrato requires specific training to prevent excessive tension in laryngeal and neck muscles. In the absence of such training, or in the context of excessive singing associated with fatigue, LMT may facilitate more efficient vocal production in tahrir singers.

Comparison between palpatory findings of the hyoid position and their acoustic, videostroboscopic, and perceptual attributes in patients with muscle tension dysphonia (with and without organic lesions).

SUMMARY: The direction in which the hyoid is pulled may change as a result of muscle tension dysphonia (MTD). The disposition usually occurs owing to paralaryngeal muscular imbalance (decompensation), which can create laryngeal dysfunction and consequently deteriorating the voice quality. This study aimed at reporting on a comparison between palpatory findings of hyoid position and their acoustic and perceptual and stroboscopic attributes among patients with MTD. DESIGN: Cross-sectional random triple-blinded study. METHOD: Palpatory, acoustic, audioperceptual, and stroboscopic findings of 39 patients with MTD were analyzed descriptively and using independent sample t test. RESULTS: Dominant perceptual vocal characteristic of patients with pulled-up hyoid position was rough and the degrees of jitter and shimmer were higher in patients with pulled-up hyoid position than in patients with pulled-down hyoid position (jitter, P=0.019; shimmer, P=0.004), whereas signal-to-noise (S/N) ratio was lower in patients with pulled-up hyoid position than in pulled-down hyoid patients, but not significantly (S/N ratio, P=0.56). The dominant perceptual characteristic of patients with pulled-up hyoid position was rough voice, whereas that for pulled-down hyoid patients was strained voice. On the other hand, the dominant observable pattern in patients with pulled-up hyoid was MTD type II (lateral constriction), whereas that in patients with pulled-down hyoid was MTD type III (moderate anteroposterior constriction). CONCLUSION: There is a general congruence between the hyoid pulled direction and its perceptual, acoustic, and videostroboscopic findings in patients with MTD.