Effects of mouth rehabilitation with removable complete dentures on stimulus perception and the electromyographic activity of the orbicularis oris muscle

Maxillectomy and Flap Reconstruction of Maxillary Defects After Cancer Ablation Through the Lip-Split Parasymphyseal Mandibulotomy Approach in Patients With Advanced-Stage Maxillary Malignant Tumors

BACKGROUND

The conventional approach for maxillectomy has some common and serious complications.

AIMS

The present study evaluated the outcomes of maxillectomy and flap reconstruction after cancer ablation using the lip-split parasymphyseal mandibulotomy (LPM) approach.

METHODS

Twenty-eight patients with malignant tumors, including squamous cell carcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma, underwent maxillectomy through the LPM approach. Brown classes II and III were reconstructed with the facial-submental artery submental island flap, an extensive segmental pectoralis major myocutaneous flap, and a free anterolateral thigh flap with the use of a titanium mesh, respectively.

RESULTS

All proximal margin frozen section specimens showed negative surgical margins. Anterolateral thigh flap failure occurred in 1 patient, whereas ophthalmic and mandibulotomy complications developed in 4 and 7 patients, respectively. In all, 84.6% of the patients had satisfactory or excellent lip esthetic results. Of the patients, 57.1% were alive with no evidence of disease, whereas 28.6% were alive with disease and 14.3% died of local recurrence or distant metastasis. No significant survival difference was evident among the squamous cell carcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma groups.

CONCLUSIONS

The LPM approach can provide good surgical access, facilitating maxillectomy in advanced-stage malignant tumors with minimal morbidity. Facial-submental artery submental island flap and anterolateral thigh flap or extensive segmental pectoralis major myocutaneous flap with a titanium mesh are ideal techniques for reconstructing Brown classes II and III defects, respectively.

The comparison of tone and viscoelastic properties of superior orbicularis oris muscle in multiple sclerosis patients to healthy individuals

BACKGROUND

The orbicularis oris muscle is an important muscle for oral perception in mouth and swallowing rehabilitation. The muscle can be affected in patients with multiple sclerosis for many reasons. It is important to understand the quantitative changes in this muscle to determine the many problems associated with the cranio-facial region in multiple sclerosis. Therefore, this study aimed to compare the mechanical properties of the orbicularis oris muscle between MS patients and healthy individuals.

METHODS

A total of 55 individuals (28 with multiple sclerosis and 27 healthy) who met the inclusion criteria were evaluated. The tone and viscoelastic properties (elasticity and stiffness) of the superior orbicularis oris muscle of both groups were evaluated bilaterally in the supine position with the MyotonPro® (Myoton AS, Estonia) device. The reference point of the muscle is accepted as the right and left paramedial philtrum dimple.

RESULTS

It was observed that there was no difference in terms of stiffness values of the right and left orbicularis oris muscles of both groups (p>0.05). The tone and the elasticity of the muscle on both sides were higher in the HI group than MS group (p<0.05).

CONCLUSION

We think that the orbicularis oris muscle has a central location in the facial region, and that this muscle may be the key muscle for the symptoms arising from many neurological mechanisms. The decrease in muscle tone and elasticity may be the beginning of the changes in MS patients. We believe that the data from this muscle will be useful for comparative studies.

Effect of Rehabilitation with a New Ocular Prosthesis on Electromyography of the Occipitofrontalis, Temporal, Masseter, and Sternocleidomastoid

Objectives  The aim of this study was to verify during facial expressions (“happy,” “sad,” “fearful,” “angry,” “surprised,” and “disgusted”) if: (1) there would be difference in the electromyography (EMG) of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles on the normal side (NS) compared with the affected side (AS) (without the use of an ocular prosthesis) in individuals with unilateral absence of the eyeball, and (2) the rehabilitation with a new ocular prosthesis would affect the EMG of the muscles studied on the AS in these individuals.

Materials and Methods  Thirteen individuals, without temporomandibular disorder, with good health, with unilateral absence of the eyeball (the eye must have been removed by evisceration or enucleation), and users or nonusers of an ocular prosthesis were included. EMG of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles was performed during rest and facial expressions (“happy,” “sad,” “fearful,” “angry,” “surprised,” and “disgusted”) before (T0) and 90 days after (T1) rehabilitation with a new ocular prosthesis. The analyses were performed in T0 on NS and AS (without the use of an ocular prosthesis), and in T1 on AS with the new ocular prosthesis.

Statistical Analysis  All data were submitted to the Student's t -test with p  < 0.05.

Results  There was no statistically significant difference comparing the AS with the NS in T0 for all muscles studied, during all facial expressions evaluated ( p  > 0.05). There was no statistically significant difference comparing the AS in T0 with itself in T1 for all muscles studied, during all facial expressions evaluated ( p  > 0.05).

Conclusion  Eye loss did not affect the EMG of studied muscles when comparing NS with AS (without the use of an ocular prosthesis). The rehabilitation with ocular prosthesis was not capable of changing the EMG on AS.

The Thermal Influence of Oral Rehabilitation on the Cranio-Cervico-Mandibular Complex: A Thermographic Analysis

PURPOSE

Assess the thermal effect of prosthodontic treatment on the cranio-cervico-mandibular complex using infrared thermography.

METHODS

The treatment group was composed of adults of both sexes who underwent a prosthodontic treatment in which at least posterior occlusal contacts were added and/or the vertical dimension of occlusion was reestablished. The control group (CG) was constituted of adult subjects of both sexes, with no more than a single missing posterior tooth, excluding third molars. Thermograms were taken of the treatment group with a Flir i7 IR camera both before oral rehabilitation (TGB; n = 33) and two months after treatment was concluded (TGA; n = 19). CG (n = 33) had only one occasion for data acquisition.

RESULTS

Statistically significant differences were found when the thermal difference (ΔT) and the health status of the orbicularis oris muscle were compared between the TGB and the TGA groups (p = 0.020 and p = 0.003, respectively). By comparing the health status of the masseter muscle between the CG and TGB, statistically significant differences were also observed (p = 0.030).

CONCLUSION

A prosthodontic treatment appears to have a minimum or null effect on the ΔT and/or on the health status of the TMJ and the temporal muscle. In contrast, orbicularis oris muscles exhibited significant thermal variations.

Are implant-supported removable partial dentures a suitable treatment for partially edentulous patients? A systematic review and meta-analysis

STATEMENT OF PROBLEM

A consensus on the clinical performance of implant-supported removable partial dentures (ISRPDs) is lacking.

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the clinical performance of ISRPDs in terms of the implant survival rates, marginal bone loss, and patient-reported outcome measures (PROMs).

MATERIAL AND METHODS

Four electronic databases (MEDLINE/PubMed, EMBASE, Web of Science, and Cochrane Library) were independently searched by 2 reviewers for articles published up to December 2020. A single-arm meta-analysis was performed to evaluate the implant survival rates and marginal bone loss by using the R program. The Cochrane collaboration tool was used to evaluate the risk of bias of randomized controlled trials (RCTs), and the Newcastle-Ottawa scale for non-RCT studies.

RESULTS

Sixteen studies were included, with a total of 334 participants and a mean age of 58 years. The participants received a total of 581 dental implants, 475 conventional and 106 mini-implants. All included studies reported implant survival rate above 90% (range: 92% to 100%). Meta-analysis indicated a high proportion of implant survival rates of 3% (95% confidence interval [CI]: 2% to 5%) and a low mean raw score of marginal bone loss 0.98 mm (CI: 0.61 to 1.36 mm). Compared with conventional RPDs, improved patient quality of life and satisfaction were reported by studies that evaluated ISRPDs. RCT studies exhibited a low risk of bias for most domains, while most non-RCT studies were classified as good quality.

CONCLUSIONS

ISRPDs exhibited high implant survival rates and acceptable bone loss with improvement in the quality of life and satisfaction of patients when compared with conventional RPDs. Therefore, they can be considered suitable for the rehabilitation of partially edentulous patients.

Age Related Changes of Superior Orbicularis Oris Muscle in Terms of Tone and Viscoelastic Properties

OBJECTIVE

To examine the age-related changes in the viscoelastic properties and tone of the superior orbicularis oris muscle by a portablehand-held myotonometer.

METHODS

A total of 128 individuals (65 female, 63 male) who met the inclusion criteria were evaluated. Individuals were divided into 2 groups as under 40 years old (Group 1), and above (Group 2). The viscoelastic properties and muscle tone of orbicularis oris muscle were evaluated bilaterally in supine position with the Myoton PRO (Myoton AS, Estonia) device from the skin overlying the orbicularis oris. The reference point is accepted as the right and left paramedial philtrum dimple. The statistical analysis was performed.

RESULTS

There was no statistically significant difference in the elasticity values of the right and left orbicularis oris muscles of the Group 1 and Group 2 individuals. There was a difference between the groups when the tone and stiffness values of both groups were compared. It was determined that individuals over the age of 40 had higher muscle tone and stiffness. All mechanical properties of the superior orbicularis oris muscle between the male and female individuals in Group 1 were different. The values are higher in the female gender. The elasticity values in both genders in Group 2 were similar. Tone and stiffness parameters were different between genders.

CONCLUSIONS

Myoton PRO can be recommended as an alternative device in the quantitative evaluations of post-operative follow-ups, and pre/post rehabilitation in terms of viscoelastic parameters of the muscle.

Effects of rehabilitation with complete dentures on bite force and electromyography of jaw and neck muscles and the correlation with occlusal vertical dimension

OBJECTIVES

The purpose of this study was to assess the effects of oral rehabilitation with complete dentures on bite force and electromyography of the suprahyoid and sternocleidomastoid muscles, and their correlation with occlusal vertical dimension (OVD). The research questions were "What are the effects of rehabilitation with complete dentures on bite force and electromyography of suprahyoid and sternocleidomastoid muscles, and how are they correlated with OVD?"

MATERIALS AND METHODS

Patients who are wearers of unsatisfactory removable complete dentures were attended in three sessions (T0, T1, and T2). At T0, while the patients still wore the old dentures, they were submitted to bite force and surface electromyographic exams of the suprahyoid and sternocleidomastoid muscles. These exams were repeated, and the OVD was measured while the patients wore their old and new prostheses, 30 days after insertion of the new prosthesis (T1). The exams were repeated 100 days after the insertion of the new prosthesis (T2). The data were submitted to the Shapiro-Wilk normality test, analysis of variance (ANOVA), and Pearson correlation and linear regression, all with 5% significance.

RESULTS

Fifteen patients participated in the study. No statistically significant difference was observed for bite force or electromyography in T0, T1, or T2. However, the correlation and regression tests showed important interactions between the OVD and maximum voluntary occlusal bite force, as well as the OVD and electromyography during deglutition for the suprahyoid muscles.

CONCLUSION

Rehabilitation did not impact bite force nor the activity of the assessed muscles (electromyography). On the other hand, OVD was shown to be an important factor for bite force, and deglutition of water after rehabilitation.

CLINICAL RELEVANCE

This study shows what are the influences of rehabilitation on oral functions and reinforces the importance of corrected reestablishment of OVD because it has been found to be an important factor for bite force and electromyography during deglutition.

Bilateral, buccinator myomucosal advancement flaps to reconstruct central upper labial myomucosal defects after ablation of early-stage cancer in minor salivary glands

BACKGROUND

Reconstruction of upper labial myomucosal defects is surgically challenging.

AIMS

We evaluated whether central defects could be repaired using bilateral, buccinator myomucosal advancement flaps (b-BMAFs).

METHODS

We evaluated five patients with early-stage, minor salivary gland mucoepidermoid carcinomas (low-grade [n = 2], intermediate-grade [n = 2], and high-grade [n = 1]) who underwent central, upper labial myomucosal reconstruction using b-BMAFs after cancer ablation. We treated two men and three women aged 25-59 years. Tumors ranged in size from 1.8 × 1.8 to 2.5 × 2.2 cm. Clinical stages were I and II in two and three patients, respectively. Defect dimensions ranged from 2.8 × 2.8 to 3.5 × 3.2 cm.

RESULTS

All patients underwent successful reconstruction of central, upper labial myomucosal defects using b-BMAFs and were satisfied with the esthetic results. Adequate orbicularis oris and speech function were maintained. No reduction in mouth opening was observed. Patients were followed up for 24-36 months; one pulmonary metastasis was observed at 36 months postoperatively.

CONCLUSION

Placement of b-BMAFs is safe and feasible when reconstructing central, upper labial myomucosal defects after ablation of early-stage, minor salivary gland cancer.

Vermilionectomy followed by reconstruction of the vermilion mucosa using allograft dermal matrix in patients with actinic cheilitis of the lower lip

BACKGROUND

When treating actinic cheilitis (AC), it is essential to minimize the risk of malignant transformation (MT) and maintain lip functionality and cosmesis.

AIMS

We evaluated the outcomes of vermilionectomy followed by reconstruction of the vermilion mucosa using allograft dermal matrix (ADM) in patients with AC of the lower lip.

MATERIALS AND METHODS

We evaluated eight patients with lower lip AC who underwent vermilion mucosa reconstruction using ADM after vermilionectomy. We enrolled five males and three females ranging in age from 55 to 70 years (mean, 62.1 years). The ADM ranged in area from 1.3 × 5.0 to 1.7 × 5.8 cm (median, 1.6 × 5.5 cm). All patients were followed up for at least 3 months postoperatively by a panel of three surgeons who assessed the esthetic results, and orbicularis oris and speech functions.

RESULTS

All patients underwent successful reconstruction of the vermilion mucosa using ADM after vermilionectomy, without complications. The postoperative esthetic results, and the orbicularis oris and speech functions, were satisfactory to excellent in all patients. Patients were followed up for 18-38 months (median, 26.1 months). No MT or recurrence was noted.

CONCLUSIONS

Vermilionectomy followed by reconstruction of the vermilion mucosa with ADM is safe and feasible for AC patients.

Longevity of complete dentures: A systematic review and meta-analysis

STATEMENT OF PROBLEM

Patients and clinicians are aware of the efficacy and benefits of complete dentures, but evidence regarding their longevity is limited.

PURPOSE

The purpose of this systematic review was to examine the literature describing the longevity of complete dentures and to review variations in longevity by denture type and duration of follow-up.

MATERIAL AND METHODS

Four electronic databases were searched by using key terms: MEDLINE, CINAHL (EBSCO), Dentistry and Oral Sciences Databases, and The Cochrane Library. Studies meeting the inclusion criteria were reviewed according to an established protocol and data extracted. Reference lists of identified studies were examined. Risk of bias was assessed by using the AXIS tool. Weighted means and weighted standard deviations were calculated. Pooled complete denture failure proportions were estimated by using random effects models based on the DerSimonian and Laird method.

RESULTS

The search yielded 21 607 unique abstracts, of which 273 met the inclusion criteria. Assessment of the full-text articles reduced this number to 42. Of these, 24 studies were rated as having low risk of bias and 18 as very low. The weighted mean ±standard deviation longevity of maxillary complete dentures was 10.3 ±3.8 years, of mandibular dentures was 8.6 ±2.6 years, and of both maxillary and mandibular dentures was 10.8 ±4.7 years. The pooled failure proportion for complete dentures observed for 2 years or less was 0.05 (95% confidence interval [CI]: 0.00-0.10), 5 to 6 years was 0.12 (95% CI: 0.08-0.16), and 10 years or more was 0.41 (95% CI: 0.28-0.53).

CONCLUSIONS

Complete dentures, fabricated primarily in university settings, were found to have a weighted mean ±standard deviation longevity of 10.1 ±4.0 years. The failure rate of these prostheses increased with denture age, and the longevity of maxillary dentures was greater than that of mandibular dentures.

Comparison of the reconstruction of through-and-through cheek defects involving the labial commissure following tumor resection using four types of local and pedicle flaps

Background

The reconstruction of through-and-through cheek defects involving the labial commissure following cancer ablation is a surgical challenge.

Methods

This study evaluated 35 patients with buccal squamous cell carcinoma (SCC) involving the labial commissure who underwent Abbe–Estlander (A-EF), folded extended supraclavicular fasciocutaneous island (SFIF), folded pectoralis major muscle (PMMF), or folded extended vertical lower trapezius island myocutaneous (TIMF) flap reconstruction of through-and-through cheek defects involving the labial commissure following radical resection.

Results

The A-EF and SFIF groups differed significantly (P < 0.05) from the PMMF and TIMF groups in terms of tumor clinical stage and type of treatment. The inner PMMF (median 6.3 × 4.5) and TIMF (median 9.8 × 6.7) skin paddle dimensions were larger than those of the A-EF (median 1.8 × 2.2) and SFIF (median 5.5 × 4.3) groups (P < 0.05). The outer PMMF (median 6.3 × 6.6) and TIMF (median 9.8 × 13.2) dimensions were larger than those of the A-EF (median 1.8 × 3.8) and SFIF (median 5.5 × 4.6) groups (P < 0.05). The esthetic results, orbicularis oris function, and speech function were significantly (P < 0.05) better in the A-EF group than in the SFIF, PMMF, and TIMF groups. The patients were followed for 6–38 months (median 26.8, 25.0, 22.1, and 20.8 months in the A-EF, SFIF, PMMF, and TIMF groups, respectively). At the final follow-up, 4 (80.0%) patients in the A-EF, 7 (87.5%) in the SFIF, 5 (55.6%) in the PMMF, and 5 (38.4%) in the TIMF groups were alive with no disease; 1 (20.0%), 1 (22.2%), 2 (22.2%), and 4 (30.8%) patients, respectively, were alive with disease; and 2 (22.2%) patients in the PMMF and 4 (30.8%) in the TIMF group had died of local recurrence or distant metastases at between 9 and 38 months. There was a significant survival difference in the A-EF and SFIF groups compared with the PMMF and TIMF groups (P < 0.05).

Conclusions

The A-EF is suitable for reconstructing defects of clinical stage II disease; the SFIF for clinical stage II or III disease; the PMMF for clinical stage III or IV; and the TIMF for clinical stage rCS III or rCS IV disease.

Evaluation of the level of cortisol, capillary blood glucose, and blood pressure in response to anxiety of patients rehabilitated with complete dentures

BACKGROUND

The aim was to analyze the levels of stress of edentulous patients through the state-trait anxiety inventory (STAI) and salivary flow through the visual analogue scale (VAS) xerostomia questionnaire, as well as analyze the levels of cortisol, capillary blood glucose, and blood pressure (BP) before and after the installation of complete dentures.

METHODS

Fifty patients were evaluated. The STAI and VAS xerostomia questionnaire were applied before the installation of the prosthesis, on the day of its installation, and 1 month after the last recall visit. The BP measurement, as well as salivary and blood collections, were performed before the installation of the prothesis, and 1 month after the last recall visit. Data from the VAS xerostomia questionnaire and cortisol levels were submitted to ANOVA and the Tukey test (P = .05). Data from the STAI, as well as blood glucose and BP levels, were submitted to the Chi-square test (P = .05). The correlation between cortisol and blood glucose and between cortisol levels and BP was analyzed.

RESULTS

There was no statistically significant association between the questions of the VAS xerostomia questionnaire, STAI-state and STAI-trait scores, or the periods analyzed. However, the cortisol level collected in the morning decreased after the installation of the prosthesis. There was a correlation between cortisol and blood glucose and BP levels.

CONCLUSIONS

The installation of complete dentures was beneficial for patients since it was probably responsible for the cortisol level reduction.

Teaching Complete Denture Procedures to Dental Students by Conventional or Simplified Methods: A Randomized Clinical Trial

With populations aging around the world, the need for complete dentures is likely to increase in Brazil and other developing countries, as well among low-income populations globally, making the teaching of cost-efficient techniques to dental students essential. The aim of this study was to evaluate the effectiveness of complete dentures fabricated by the simplified method in comparison to the conventional method regarding patients' oral health-related quality of life (OHRQoL) and satisfaction, dentures' functional quality, and masticatory performance of patients who were rehabilitated by dental students. From February 2016 to April 2017, final-year dental students at the Federal University of Alfenas, Brazil, were instructed to fabricate new complete dentures for 36 edentulous patients, who were randomly divided into two groups according to denture manufacturing method: simplified method or conventional method. Patients' OHRQoL and satisfaction and the prostheses quality were evaluated at one, three, and six months. Masticatory performance was evaluated at three months. The results showed there was no significant difference between the two methods regarding OHRQoL, patient satisfaction, prostheses quality, or masticatory performance (p>0.05). All aspects evaluated also remained constant for the same group (simplified method or conventional method) in all periods of evaluation (p>0.05). The study concluded that the simplified method for complete denture fabrication was able to produce protheses with functional quality and patient satisfaction comparable to those produced with the conventional method, even when made by dental students.

The Influence of Age, Gender, Mandibular Bone Height, Previous Experience with Prostheses, and Fabrication Methods on Masticatory Performance of Complete Denture Wearers

PURPOSE

To evaluate the influence of age, gender, mandibular bone height, previous experience with prostheses, and methods for denture fabrication on masticatory performance of complete denture (CD) wearers.

MATERIALS AND METHODS

For this study, 29 individuals treated with CDs fabricated by simplified or conventional methods had their masticatory performance assessed 4 weeks after the prostheses' adjustment and control, using the sieve method and almonds as a natural food test. Experimental variables related to age, gender, and previous use of complete dentures were collected from dental records. Panoramic digital radiographs were used to determine mandibular bone height according to the criteria described by the American College of Prosthodontists. Data on masticatory performance were assessed using t-test for independent samples to make comparison between simplified and conventional methods, and a multiple linear regression analysis was performed to evaluate the influence of age, gender, previous experience with CDs, and mandibular bone height on masticatory performance using SPSS software with a significance level of 5%.

RESULTS

There was no significant influence regarding the method for CD fabrication (p = 0.92), age (p = 0.36), mandibular bone height (p = 0.37), and previous experience with prostheses (p = 0.15) on masticatory performance of CD wearers. Female patients presented lower masticatory performance than male (p = 0.04) patients did.

CONCLUSIONS

Considering the limitations of this study, it was concluded that gender might be considered a risk factor for masticatory performance of CD wearers. Female patients demonstrated reduced masticatory performance in comparison to male patients.