Speech effects of Hawley and vacuum-formed retainers by acoustic analysis: A single-center randomized controlled trial

Objective:To investigate the effects of alteration on speech articulation of adult patients between Hawley retainers and vacuum-formed retainers by an objective acoustic analysis of vowels and voiceless fricatives.Materials and Methods:Twenty adults, aged 19.0–29.0 years, who had just finished active orthodontic treatment were included in this study. They were divided into a Hawley retainer group and a vacuum-formed retainer group by sortation randomization method. The assessment of speech sounds was performed objectively using acoustic analysis before and after retainer application at the following time points: before wearing (T0), immediately after wearing (T1), and at 24 hours (T2), 1 week (T3), 1 month (T4), and 3 months (T5).Results:The production of /з:/, /i:/, /f/, /θ/, /s/, and /∫/ sounds for the Hawley retainer group and /i:/, /θ/, /s/, and /∫/ sounds for the vacuum-formed retainer group showed severe speech impairment according to acoustic analysis (P < .05). A comparison of the Hawley retainer group with the vacuum-formed retainer group revealed that the performance of /i:/, /f/, and /s/ sounds were significantly different (P < .05).Conclusion:Although sound distortion could be found in both the Hawley retainer group and the vacuum-formed retainer group, changes in articulation were more obvious in the Hawley retainer group.     

透明压膜保持器与Hawley保持器对拔牙病例的保持效果比较

目的　比较透明压膜保持器与Hawley保持器对拔牙病例保持的临床效果差异。方法　选取40例儿童患者正畸完成病例,均拔除4个第一前磨牙,正畸治疗完成后随机分为2组,各20例：A组戴用透明压膜保持器,B组戴用Hawley保持器。采集治疗刚结束(T1)及治疗完成1年后(T2)的记存模型,分别进行PAR指数评价,用SPSS 13.0软件对实验数据进行统计分析。结果　治疗完成1年后,两组间牙齿排列的保持效果显著不同(P＜0.05),其余指标未发现显著性差异。结论　对于拔除第一前磨牙的病例,透明压膜保持器在牙齿排列的保持效果上明显优于Hawley保持器。     

Posterior occlusion changes with a Hawley vs Perfector and Hawley retainer: A follow-up study

Objective:To characterize postorthodontic settling of the posterior occlusion of patients wearing Hawley retainers vs patients who initially wore Perfector retainers and then switched to Hawley retainers.Materials and Methods:This follow-up study was based on 40 patients (25 Perfector and 15 Hawley), who were part of a larger sample of 50 patients randomly assigned to wear either Hawley or Perfector retainers. The Perfector patients were given Hawley retainers 2 months after retainer delivery. Occlusal bite registrations were scanned and traced to quantify posterior areas of contact and near contact (ACNC). A seven-item questionnaire was used to assess the patient''s perception of occlusion. Measurements were obtained at the on the day of retainer delivery, 2 months post delivery, 6 months post delivery, and 8 months post delivery.Results:ACNC increased significantly (P < .05) during the first 6 months of retainer wear. The ACNC of the Hawley and Perfector/Hawley groups increased by 129% and 105%, respectively, over 8 months of retention. The greatest increases in ACNC occurred during the first 2 months. The ACNC further increased between 2 and 6 months in both groups. The Perfector/Hawley group also showed slight increases in ACNC between 6 and 8 months. Overall group differences were not statistically significant. The Perfector/Hawley group perceived greater improvements in occlusion than the Hawley group, but group differences after 8 months were small.Conclusions:Substantial amounts of settling occurred at decelerating rates during the first 6 months after retainer delivery. No significant differences in ACNC were found between the Hawley and Perfector/Hawley groups after 8 months of retainer wear.     

Microbial evaluation of the effectiveness of different methods for cleansing clear orthodontic retainers: A randomized clinical trial

Objective:To compare effectiveness of brushing an Essix retainer with water only and brushing followed by soaking in one of three commercial cleansing tablets.Materials and Methods:A double-blind, parallel, randomized clinical trial with a split-mouth design was completed with 60 volunteers with specific eligibility criteria assigned to three groups to compare the cleansing effectiveness of brushing an Essix retainer with water only, followed by soaking in one of three alkaline peroxide–based commercial cleansing tablets (Retainer Brite^®, Kukis^®, and Corega^®). Each participant wore an upper Essix retainer (with an electronic microsensor) on a full-time basis for 14 days and used one of the three products on one side of the retainer for 15 min/d. The effectiveness of the cleansing tablets was tested by the scanning electron microscopy, bacterial identification, bacterial quantification, and disk diffusion methods.Results:Bacterial quantification tests demonstrated nonsignificant statistical differences between the control and test sides of the three cleansing tablets: Retainer Brite^®, Kukis^®, and Corega^® (Mann-Whitney test P-values were .6, .37, and .5, respectively). A Kruskal-Wallis test also showed nonstatistical difference in the bacterial counts between the three groups (P-value = .5). In vitro tests showed a minimal inhibition zone of Staphylococcus epidermidis only with Corega^® tablets.Conclusions:Using chemical cleansing tablets after mechanical cleansing did not significantly reduce the bacterial count in Essix retainers when compared to use of mechanical cleansing alone. However, the tablets seem to be effective against “cocci” bacterial species.     

Color fading of the blue compliance indicator encapsulated in removable clear Invisalign Teen® aligners

Objective:To evaluate the color fading in aqueous solutions of the blue dot wear-compliance indicators of the Invisalign Teen® System outside the oral cavity.Materials and Methods:The compliance indicators in the Invisalign Teen aligners were tested for color resistance in various aqueous models with no saliva involved.Results:Color fading was observed as a function of time, pH, and temperature while compliance indicators were stored in drinking water or sour soft drinks and in conjunction with the use of cleaning tablets and a dishwasher. The findings of color fading were consistent with the color changes observed when the aligners were being worn by patients. Color fading, notably as observed in connection with acidic soft drinks and cleaning techniques, introduces uncertainty into the assessment of actual patient compliance, as reflected by the fading colors of compliance indicators.Conclusion:Compliance indicators are not immune to simple intentional or unintentional manipulations. Therefore, they can best show an estimate of wear time but cannot be recommended as objective wear-time indicators.     

A comparative evaluation of lingual retainer failure bonded with or without liquid resin: A randomized clinical study with 2-year follow-up

Objective:To prospectively evaluate and compare the effect of liquid resin on lingual retainer failure after a 2-year follow-up.Materials and Methods:Fifty-two patients (26 males, 26 females) with a mean age of 18.3 ± 1.3 years at follow-up, were randomized into two groups: the resin group and the nonresin group. The lingual retainers in the resin group were bonded to the enamel surfaces with two-step bonding resin, Optibond FL, and Tetric EvoFlow. The nonresin group followed the same procedure of bonding retainers but without applying the Optibond FL. Retainer failure, calculus accumulation, and discoloration of composite pads adjacent to the retainers during the 2-year observation period were registered, compared, and statistically analyzed with a Fisher''s exact test and chi-square test.Results:In the resin group, the incidence of retainer failure was 4% and occurred at the composite-wire interface; in the nonresin group, the incidence was 27% and occurred at the enamel-composite interface. The difference between the groups was statistically significant (P  =  .049). The incidences of calculus accumulation and discoloration adjacent to the composite pads were 27% and 69% (P  =  .003 and P < .001) higher in the nonresin group, respectively.Conclusion:Application of resin in bonding of lingual retainers appears to reduce the incidence of retainer failure as well as the incidence of calculus accumulation and discoloration adjacent to the composite pads.     

Patient satisfaction with laser-sintered removable partial dentures: A crossover pilot clinical trial

Statement of problem

Clinical data regarding newly introduced laser-sintered removable partial dentures (RPDs) are needed before this technique can be recommended. Currently, only a few clinical reports have been published, with no clinical studies.

Patient satisfaction with mini‐implant stabilised full dentures. A 1‐year prospective study

The purpose of this study was to evaluate patient‐centred outcomes with regard to function and comfort after placement of mini‐implants for stabilisation of complete dentures. The trial was designed as a prospective cohort of 12‐months duration and involved 21 subjects in the age of 50–90 years having a full denture in the maxilla or the mandible with poor stability during function. Flapless installation of 2–4 narrow‐body Dentatus Atlas^® implants was performed and retention for the existing denture was obtained by the use of a silicone‐based soft lining material (Tuf‐Link^®). Patients' judgement of perceived satisfaction with function and comfort of the dentures was recorded at baseline, 1‐ and 12‐months post‐treatment using 10‐centimetre visual analogue scales (VAS) and a questionnaire. Clinical examination of the conditions of the peri‐implant soft tissues was performed at 12 months. Nineteen of the 21 patients were available for the 12‐month follow‐up examination. The two drop‐out subjects lost all implants within 1 month and rejected retreatment. Further six subjects lost 1–2 implants, but were sucessfully retreated by insertion of new implants. Overall satisfaction, chewing and speaking comfort were all markedly improved from pre‐treatment median VAS scores of around 4–5 to median scores of 9·0–10 (10 = optimal) at the final examination. The prevalence of positive answers to questions regarding stability/function of the denture increased significantly to almost 100% for all questions. Treatment involving maxillary dentures and the use of short implants (7–10 mm) was associated with an increased risk of implant failure. The results indicate that placement of mini‐implants as retentive elements for full dentures with poor functional stability has a marked positive impact on the patients' perception of oral function and comfort as well as security in social life.     

Patient satisfaction after orthodontic treatment combined with orthognathic surgery: A systematic review

Objective:To synthesize available evidence about factors associated with patients’ satisfaction after orthodontic treatment combined with orthognathic surgery.Materials and Methods:Studies that evaluated any factor associated with patients’ satisfaction after the conclusion of an orthodontic treatment combined with an orthognathic surgery were identified. Orthognathic surgical procedures should have been undertaken after completion of craniofacial growth. Any satisfaction psychometric tool was considered. No language limitation was set. A detailed individual search strategy for each of the following bibliographic databases was crafted: MEDLINE, PubMed, EBM Reviews, Web of Science, EMBASE, LILACS, and Scopus. The references cited in the identified articles were also cross-checked, and a partial gray-literature search was undertaken using Google Scholar.Results:Eight articles satisfied the inclusion criteria of this systematic review and accounted for 998 patients. The included studies showed large variation in sample size (range  =  44 to 505 patients), age (range  =  15 to 72 years old), distinct psychological evaluation tools, and time elapsed between the assessment and the completion of surgery and postorthodontic treatment. Most of the studies (five of eight) were classified as having high risk of bias.Conclusion:Factors associated with satisfaction were final esthetic outcome, perceived social benefits from the outcome, type of orthognathic surgery, sex, and changes in patient self-concept during treatment. Factors associated with dissatisfaction were treatment length; sensation of functional impairment and/or dysfunction after surgery, and perceived omitted information about surgical risks.     

Oral lichenoid lesions associated with amalgam restorations: A prospective pilot study addressing the adult population of the Basque Country

Oral lichenoid lesions (OLLs) are linked to a heterogeneous group of pathologies involving the oral mucosa that cannot be distinguished from the oral lichen planus excepting the fact that direct causal factors such as silver amalgam restorations (SARs) can be allocated to them.Purpose: To analyze the prevalence of mucosal lesions associated with SAR in a group of SAR carrying patients in the Basque Country.Study Design: A clinical prospective study was carried out on 100 adult patients over 30 years of age at the UPV/EHU Clinical Odontology Service whose rear teeth had at least one SAR. Patients were identified and mucosal lesions and amalgam restorations were characterized. Patch tests were performed on patients with lesions and amalgams were replaced with composite material. A statistical and comparative analysis was performed with the resulting data.Results: OLLs were found in 7 patients whose predominant lesion was bilateral, asymmetrical and asymptomatic white papule-macule. Lesions were related to old and corroded SARs. Patch testing was positive in two cases. SAR substitution produced an improvement in 5 cases. Conclusions: The presence of lichenoid lesions associated with SARs is infrequent in our environment and is preferentially related to old and corroded restorations. Key words:Oral mucosa, lichenoid lesions, restoration, silver amalgam, patch test.     

Mini-implant stability at the initial healing period: A clinical pilot study

Objective:To evaluate the changes of mini-implant stability over the initial healing period in humans.Material and Methods:A sample of 19 consecutively treated patients (mean age 15.5 ± 7.3 years) was examined. In each patient, a mini-implant of a size of 2 × 9 mm was inserted into the anterior palate. Implant stability was assessed using resonance frequency analysis (RFA) immediately after insertion (T0), 2 weeks later (T1), 4 weeks later (T2), and 6 weeks later (T3). Insertion depth (ID) and the maximum insertion torque (IT) were measured. Data were tested for correlations between RFA, ID, and IT. All RFA values were tested for statistically significant differences between the different times.Results:The mean ID was 7.5 ± 0.6 mm, and the mean IT was 16.8 ± 0.6 Ncm. A correlation was found between RFA and ID (r  =  .726, P < .0001), whereas no correlations between RFA and IT or between IT and ID were observed. From T0 to T1, the stability (36.1 ± 6.1 implant stability quotient [ISQ]) decreased nonsignificantly by 4.9 ± 6.1 ISQ values (P > .05). Between T1 and T2, the stability decreased highly significantly (P < .001) by 7.9 ± 5.9 ISQ values. From T2 on, RFA remained nearly unchanged (−1.7 ± 3.5 ISQ; P > .05).Conclusions:Mini-implant stability is subject to changes during the healing process. During weeks 3 and 4, a significant decrease of the stability was observed. After 4 weeks, the stability did not change significantly.     

A three-year prospective study of adult subjects with gingivitis. I: clinical periodontal parameters

AIM: The objective of this study was to monitor prospectively clinical parameters in subjects without signs of destructive periodontal disease who were involved in a primary prevention programme, and to determine the changes that occurred between yearly examinations over a 3-year period. MATERIAL AND METHODS: One hundred and twenty-six subjects aged at least 20 years with a maximum of two tooth sites with probing pocket depth (PPD)>4 mm and no proximal sites with clinical attachment loss participated in the study. Primary prevention was provided at baseline of the study and then every 6 months. Plaque, bleeding on probing (BoP) and PPD were scored at baseline, 1, 2 and 3 years. RESULTS: There were no significant changes in the plaque score over the 3 years. After year 1, the BoP score was significantly improved with 5.6%, while no further improvement in BoP was found at years 2 and 3. The mean PPD decreased from 2.3 to 2.1 mm over the 3 years (p<0.05). CONCLUSION: Although some individuals exhibiting minor signs of periodontal pathology may have benefited from the primary prevention, the overall clinical improvement was limited for such subjects in the present 3-year study.