Comparison of implant-supported rehabilitation in smokers and non-smokers with conventional and short tuberosity implants: an evaluation of prosthetic, peri-implant, and cytokine profiles

OBJECTIVE

This study aimed to assess periodontal parameters, radiographic (CBL), and prosthetic parameters along with levels of matrix metalloproteinase-9 (MMP-9) and interleukin-1β (IL-1β) in smokers undergoing rehabilitation using conventional implants and short tuberosity implants (STIs).

SUBJECTS AND METHODS

The duration of the study was six months. A structured questionnaire was made to be filled out by all participants. The participants were included in the study based on predefined inclusion and exclusion criteria for smokers and non-smokers with STIs. Peri-implant parameters were assessed based on peri-implant plaque index (PIPI), bleeding on probing (BoP), and peri-implant periodontal depth (PIPD) ≥4 mm. Collection of peri-implant crevicular fluid (PICF) and measurement of MMP-9 and IL-1β was performed using ELISA. Data related to peri-implant clinical and radiographic parameters were reported in mean and percentages. Pearson Chi-square test was employed for categorical data sets, whereas the Kruskal-Wallis test was used for the comparison of means between groups. Bonferroni post hoc adjustment test was applied for multiple comparisons. Differences were found to be significant p<0.01 RESULTS: Among the four groups, one hundred participants were included. The mean age of participants in groups 1 (44±4.5 yrs) and 3 (44±2.1 yrs) showed no significant difference from participants in groups 2 (42±3.8 yrs) and 4 (43±3.5 yrs). The duration of the smoking habit in cigarette smokers with STIs was 22.7±1.4 yrs, and cigarette smokers with conventional implants were 23.8±1.9 yrs with a daily frequency of 11.2±2.5 in group 1 and 11.33±2.1 in group 3. The means for PIPI and PIPD were found to be significantly worse in cigarette smokers with STIs (PIPI 62.4±5.9; PIPD 5.3±2.1) and conventional implants (PIPI 63.3±6.1; PIPD 5.5±1.9) compared to non-smokers with STIs (PIPI 29.2±3.6; PIPD 3.1±0.1) and conventional implants (PIPI 28.1±3.4; PIPD 3.2±0.3). BoP was significantly higher in non-smokers compared to smokers with STIs (smokers 24.2±8.3; non-smokers 36.5±21.2) and conventional implants (smokers 21.6±7.4; non-smokers 38.4±24.1) (p<0.01). The level of IL-1β (pg/ml) and the level of MMP-9 (ng/ml) were found to be significantly higher in cigarette smokers with STIs and conventional implants in comparison to non-smokers (p<0.01).

CONCLUSIONS

Periodontal (PIPI, PIPD, and BoP) along with radiographic (CBL) and prosthetic parameters were compromised in smokers compared to non-smokers. Patients with conventional implants and STI showed comparable clinical, radiographic, and prosthetic parameters among smokers. Utilization of dental services along with cessation programs should be encouraged for smokers.

Influence of mechanical debridement with adjunct probiotic therapy on clinical status and salivary cortisol levels in patients with periodontal inflammation

OBJECTIVE

The null hypothesis is that there is no difference in periodontal parameters and salivary cortisol levels (CL) among patients with periodontal inflammatory conditions (PIC) who receive non-surgical mechanical debridement (NSMD) with or without adjunct probiotic therapy (PT). The aim of this study was to assess the influence of NSMD with and without adjunct PT on clinical status and whole salivary CL in patients with PIC.

PATIENTS AND METHODS

Participants were randomly divided into four groups: Group-1: NSMD alone (n=19); Group-2: NSMD + PT (n=18); Group-3: PT + oral hygiene instructions (OHI) (n=17); and Group-4: PT alone (n=18). Lactobacillus rhamnosus SP1 (2×107 colony-forming units/day) was used for PT. Plaque and gingival indices (PI and GI), probing depth (PD) and clinical attachment loss (AL) were assessed, and whole salivary CL was assessed at baseline and at 6-week follow-up. Marginal bone levels were assessed at baseline and demographic data was collected using a questionnaire. Sample-size estimation was performed, and statistical significance was determined at p<0.05.

RESULTS

At follow-up, PI (p<0.01), GI (p<0.01), and PD (p<0.01) were significantly higher in PT + OHI and PT alone groups compared with individuals who underwent NSMD + PT and NSMD alone. At baseline and follow-up, there was no significant difference in CL in all groups. There was no statistically significant correlation between age, gender, PI, PD, GI, clinical AL, salivary flow rate, education status and salivary CL in all groups at baseline and follow-up.

CONCLUSIONS

NSMD continues to be the "gold standard" and most reliable treatment strategy for managing PIC. It is imperative to reach a consensus regarding the duration, dosage, and frequency of PT that would yield optimal results for managing PIC.

Influence of Sapindus mukorossi extract in comparison to 17% EDTA as final root canal irrigant on the sealer penetration and microleakage of dentinal tubules

OBJECTIVE

The study evaluated the effect of Sapindus mukorossi (SM) extract as a final root canal irrigant on sealer penetration (SP) in dentinal tubules and microleakage.

MATERIALS AND METHODS

Samples were selected based on inclusion and exclusion criteria. An access opening in all samples was performed and the working length was decided using pro taper for canal finishing along with constant irrigation. Specimens were randomly divided into 3 groups. Group 1 was irrigated with 3 ml of 17% EDTA; group 2 was irrigated with SM irrigant and group 3 samples were irrigated with 0.9% saline. After obturation, samples were vertically placed in 1% methylene blue dye cut in half longitudinally, and viewed under a stereomicroscope. Analysis of SP in the dentinal tubule was assessed using scanning electron microscopy (SEM). For microleakage assessment, mean and standard deviation were reported and One-Way ANOVA was applied. SP was compared using Kruskal-Wallis' test. For inspecting the interaction between SM/EDTA and NaOCl, Fisher's exact test was applied. No statistically significant difference between microleakage in any of the tested groups was observed. The control group showed minimum leakage as compared to EDTA and SM.

RESULTS

The results displayed that there was no significant difference, (p=0.67), between dentinal tubule SP at 2 mm. A significant difference between dentinal tubule SP among groups at 5 mm was observed (p<0.05).

CONCLUSIONS

SM ethanolic extract showed comparable outcomes of smear layer removal and sealer penetration to 17% EDTA, as a final irrigant in root canal cleaning. Therefore, SM has the potential to be used as an adjuvant final irrigant in conjunction with NaOCl.

Evaluation of gingival displacement, bleeding and ease of application for polytetrafluoroethylene (PTFE) and conventional retraction cord - a clinical trial

OBJECTIVE

Conventional use of retraction cord in soft tissue management is effective only when the non-resilient nature of material does not jeopardize gingival health. Therefore this study aims to clinically evaluate the gingival displacement, ease of application and bleeding from polytetrafluoroethylene (PTFE) retraction cord.

PATIENTS AND METHODS

This study is a single-center, parallel-group, randomized controlled clinical trial (1:1). Sixty patients indicated for full coverage metal-ceramic restoration for first molars were enrolled and randomly allocated to experimental (PTFE Cord) and control (conventional plain retraction cord) groups. After crown preparation and isolation, a pre-displacement impression was made. Assigned gingival displacement material was applied for 5 minutes, followed by post-displacement impression. Casts were prepared and used for assessment of mean horizontal gingival displacement by measuring displacement using a stereomicroscope (20 x). Post-displacement gingival bleeding and ease of application were also assessed clinically. t-test and Chi-square tests were used for statistical assessment of gingival displacement, gingival bleeding and ease of application.

RESULTS

Gingival displacement, bleeding and ease of application were similar among study groups (p > 0.05). Mean gingival displacement in the experimental group was 197.1 µm, and 167.7 µm in the control group. Bleeding was observed in 30% and 20% of cases of experimental and control group, respectively. Ease of application was 'difficult' in 53.3% and 43.3% of cases of experimental and control group, respectively. Non-impregnated gingival retraction cord and PTFE cord displayed similar outcomes of gingival displacement, ease of placement and bleeding after cord removal.

CONCLUSIONS

Post-displacement bleeding and discomfort for PTFE cord placement suggest that this technique needs improvement. Therefore further studies are warranted to improve and investigate the physical and biological response to PTFE retraction cord.

Clinical peri-implant outcomes, technical complications, and patient satisfaction with single vs. splinted crown supported implants in the anterior mandible region of diabetic individuals

OBJECTIVE

To compare the clinical and radiographic peri-implant parameters around narrow diameter implants (NDI) supported single (NDISCs) and splinted crowns (NDISPs) in the anterior maxilla of non-diabetics and type 2 diabetes mellitus patients (T2DM).

MATERIALS AND METHODS

The clinical and radiographic parameters of NDISC and NDISP were assessed in the anterior mandibular jaw of T2DM and non-diabetic individuals. Plaque index (PI), bleeding on probing (BoP), probing depth (PD) and crestal bone levels were recorded. Technical complications and patient satisfaction were also assessed. ANOVA (one-way analysis of variance) was used to compare the inter-group means of clinical indices and radiographic bone loss while Shapiro-Wilk was used to compute the normal distribution of dependent variables. A p-value of less than 0.05 was considered significant.

RESULTS

Sixty-three patients (35 males and 28 females) were part of the study out of which 32 were non-diabetics and 31 were T2DM patients. A total of 188 implants (124 NDISCs and 64 NDISPs) having moderately roughened topography were used for the study. The mean glycated hemoglobin in the non-diabetic group was 4.3 while that in the T2DM group was 7.9 with an average diabetic history of 8.6 years. Peri-implant parameters, including PI, BoP, and PD, were comparable between the single crown and splinted crown groups. However, there was a statistically significant difference in PI, BoP, and PD when a comparison was made between the non-diabetes and T2DM groups (p<0.05). An overall 88% of the patients were satisfied with the esthetics of the crowns while 75% of the subjects were satisfied with the function of the crowns.

CONCLUSIONS

Narrow diameter implants of both types had satisfactory clinical and radiographic outcomes within non-diabetic and diabetic individuals. However, clinical and radiographic parameters were worse in type 2 diabetes mellitus patients when compared to non-diabetics.

Efficacy of subgingival minocycline hydrochloride delivery as an adjunct to non-surgical mechanical debridement for the treatment of peri-implantitis in patients with type-2 diabetes mellitus

OBJECTIVE

The aim was to assess the efficacy of subgingival minocycline hydrochloride (MH) delivery with non-surgical mechanical debridement (NSMD) for treating peri-implantitis in patients with type-2 diabetes mellitus (DM).

PATIENTS AND METHODS

Type-2 diabetic and non-diabetic patients with peri-implantitis were included. In the test-group, patients underwent NSMD with a single session of MH delivery. In the control-group, patients underwent NSMD alone. Hemoglobin A1c (HbA1c), modified plaque-index (mPI), modified gingival index (mGI), probing-depth (PD) and crestal bone loss (CBL) were measured at baseline and at 6-month follow-up. Level of significance was set at p<0.01.

RESULTS

Thirty type-2 diabetic and 30 healthy individuals with peri-implantitis were included. There was a significant reduction in mPI (p<0.01), PD (p<0.01) and mGI (p<0.01) at 6 months among patients with and without type-2 DM in the test and control groups. There was no significant difference in peri-implant parameters in all patients at the 6-month follow-up. There was no significant difference in HbA1c and CBL among patients with and without type-2 DM in the test and control groups when baseline values were compared with those at 6 months of follow-up.

CONCLUSIONS

A single application of subgingival MH delivery is as effective as NSMD alone for the treatment of peri-implantitis in type-2 diabetic patients.

Implant abutment disinfection using plasma of argon and 0.2% and chlorhexidine gel applications immediately before prosthesis delivery: clinical and radiographic status at 5-years of follow-up

OBJECTIVE

The purpose of this five-year follow-up study was to investigate the clinical and radiologic status of implants that had undergone abutment disinfection immediately prior to prosthetic loading (PL) using plasma of argon (PA) or 0.2% chlorhexidine (CHX) gel.

PATIENTS AND METHODS

Sixty patients who had had an implant-supported prosthesis fitted at least five years previously were recruited for this study. In groups 1, 2, and 3, implant abutment disinfection was performed using PA, 0.2% CHX, and a vapor protocol, respectively. Modified plaque index (mPI), modified bleeding index (mBI), probing depth (PD), and mesial and distal crestal bone loss (CBL) were measured. A questionnaire on routine oral hygiene, smoking habits, and systemic health status was also administered. Sample size estimation was performed, and group comparisons were made. Probability values less than 0.05 were considered statistically significant.

RESULTS

Group 1, 2, and 3 included 20 (20 implants) patients each. At five-year's follow-up, there was no difference in mBI, mPI, and PD in all groups. There was no significant difference in peri-implant CBL in all patients. None of the patients were immunosuppressed or had periodontal disease, and or had used nicotinic products within the past five years. Toothbrushing twice daily was reported by at least 90% of individuals in all groups. Flossing of interproximal spaces once daily was reported by at minimum 60% of individuals in all groups.

CONCLUSIONS

Disinfection of implant abutments directly before PL can be performed using AP, or 0.2% CHX gel.

Efficacy of adjunct subgingival minocycline delivery for treatment of peri-implantitis in moderate cigarette smokers

OBJECTIVE

Localized subgingival minocycline hydrochloride (MH) delivery as an adjuvant to with non-surgical mechanical debridement (NSMD) is useful for the treatment of periodontitis; however, there are no trials that have assessed the efficacy of subgingival MH delivery with NSMD for the treatment of peri-implantitis in cigarette-smokers and non-smokers. This randomized controlled trial assessed the efficacy of subgingival MH delivery with NSMD for the treatment of peri-implantitis in cigarette-smokers.

PATIENTS AND METHODS

Self-reported current cigarette-smokers and non-smokers with peri-implantitis were encompassed. These individuals were subdivided into 2-subgroups. Patients in test- and control groups received NSMD with and without a single delivery of subgingival MH. Modified-gingival-index (mGI), modified-plaque-index (mPI), probing-depth (PD) and crestal-bone-loss (CBL) were measured at baseline and at 6-months' follow-up. Demographic-data was also collected. Level of significance was set at p<0.01.

RESULTS

Twenty-four cigarette-smokers and 24 non-smokers with peri-implantitis were included. There was a significant reduction in mPI (p<0.01), mGI (p<0.01), PD (p<0.01) at 6-months among patients with and without type-2 DM in test- and control-groups. There was no significant difference in peri-implant mPI, PD and mGI, patients with and without type-2 diabetes in test- and control-groups at 6-months of follow-up. There was no significant difference in CBL in all patients at 6-months of follow-up.

CONCLUSIONS

A single application of subgingival MH delivery is as effective as NSMD alone for the treatment of peri-implantitis in cigarette-smokers and non-smokers.

Immunohistochemical expression of PCNA, STRO-1 and CD 44 in the healing of experimentally induced periapical lesions in rats

OBJECTIVE

The aim of the study was to determine the expression of cell proliferating marker, anti-proliferating cell nuclear antigen (anti-PCNA) and mesenchymal stem cell (MSC) markers (anti-STRO-1 and anti-CD44) in periapical periodontitis and their role in the healing of periapical lesion in periapical periodontitis.

MATERIALS AND METHODS

Ninety Sprague-Dawley male rats (100 g) were divided into 3 groups: Experimental group I (EG I: n = 30), experimental group II (EG II: n=30) and control group (CG: n = 30). Periapical lesions were experimentally developed by leaving the dental pulp of maxillary first molars mesial root open to oral environment for 4 weeks. Conventional root canal treatment was performed in EG II. Maxillary first molars along with alveolar bone were resected and fixed. The processed samples were stained with routine hematoxylin and eosin (H&E), and evaluated immunohistochemically using antibodies against anti-PCNA, anti-STRO-1, and anti-CD44 polyclonal antibodies. Data were analyzed using Chi-square test and a p-value of <0.05 was considered significant.

RESULTS

Immunostaining of anti-PCNA showed 30%, 70% and 53.3% positive staining in CG, EG I, and EG II, respectively (p<0.001). Moreover, the CD44 staining was 20% in CG in contrast to 63.6% in EG I and 43.3 in EG II. STRO-1 staining in CG was 10%, 50% in the EG I and 36.6% in the EG II (p<0.001).

CONCLUSIONS

Periapical inflammatory tissues expressed significant proliferative cell marker PCNA and mesenchymal stem cell markers STRO-1, and CD44. These findings further reaffirm the promising role of mesenchymal stem cells in the healing of periapical periodontitis.

The effect of 805 nm near-infrared photobiomodulation on proliferation and differentiation of bone marrow stem cells in murine rats

OBJECTIVE

To evaluate the effect of near infra-red gallium-aluminium-arsenide (GaAlAs) diode laser (805 nm) irradiation on proliferation and differentiation of rat femoral bone marrow-derived mesenchymal stem cells (BMSCs) cultured in osteogenic medium.

MATERIALS AND METHODS

BMSCs were obtained from femurs of 60 Sprague Dawley rats (200 gm). The control group comprised isolated BMSCs supplemented with an osteogenic differentiation medium. On the other hand, in the experimental group, the BMSCs were irradiated with a near-infrared laser in addition to an osteogenic differentiation medium. The experimental group was irradiated with a soft tissue laser comprising of allium-aluminium-arsenic (Ga-Al-Ar) Diode at a near-infrared wavelength of 805 nm in continuous mode. The different output powers applied were 0.5 W, 1.0 W, 1.5 W and 2.0 W respectively. Various energy levels of 1, 4, 7 and 10 J were used for irradiation. Alkaline phosphatase (ALP) assay and Alizarin staining were performed to confirm osteogenic differentiation. Statistical analysis was done using a one-way ANOVA and a p-value of <0.05 was considered significant.

RESULTS

According to our findings, 1.27 J/cm2 was the optimal energy density value that significantly increased the BMSC proliferation at the output of 1.5 W with the power density of 1.27 W/cm2. On 1.27 J/cm2, there was a significant difference compared to the control group on the first day, and the osteogenic differentiation increased significantly on the 4th day compared to the 1st day.

CONCLUSIONS

According to our findings, 1.27 J/cm2 was the optimal energy density value that significantly increased the BMSC proliferation at the output of 1.5 W with the power density of 1.27 W/cm2.

Knowledge attitude and practice of safety measures for corona virus disease - 19 (COVID-19) among general population

Objective

To evaluate the knowledge, attitude, and practice of general population for Corona virus disease 19 (COVID-19).

Methods

A total of 950 participants submitted an online self-administered questionnaire, which was developed through literature search and validated. The online survey link was distributed through various social media platforms (WhatsApp, Instagram, Facebook, LinkedIn, Twitter, Snapchat, Pinterest, and Tumblr). And 861 forms were included in the study after checking for completion of relevant response from participants, whereas 89 forms were excluded. The data were analyzed through Statistical Package for Social Sciences. Descriptive statistics were performed for percentage and frequency determination of quantitative and qualitative variables. Spearman's correlation and Chi square test were performed to control confounders and association of knowledge, attitude, and practices with gender and education level. The P value <0.05 was considered as statistically significant.

Results

More than two third of the population was aware of COVID-19 and three fourth had had bachelor's degrees, whereas 18% had master level education. 85% have not attended any courses, awareness campaigns, and lectures to inculcate recent and updated knowledge. 83% believed that COVID-19 is a serious threat to the community; hence, prevention strategies should be adopted. There was no significant relationship (p = 0.23) between knowledge, attitude, and practice levels with gender, whereas a significant relationship (p = 0.01) was noted with education of participant. Similarly, a significant relationship (p = 0.00) was seen between knowledge and practices of participants toward COVID-19.

Conclusion

The studied population displayed adequate knowledge, attitude, and practice to combat COVID-19. However, we also find a knowledge gap between information source and perception of COVID-19 among our study participants. Therefore, there is a critical need for effective education and widespread public campaigns aiming to enhance relevant and contemporary information related to prevention and management of COVID-19.

Influence of involuntary cigarette smoke inhalation on osseointegration: a systematic review and meta-analysis of preclinical studies

There are no studies that have systematically reviewed the influence of involuntary cigarette smoke inhalation (ICSI) on the stability of implants. The aim of the present study was to perform a systematic review and meta-analysis of preclinical studies that assessed the influence of involuntary cigarette smoke inhalation ICSI on osseointegration. Indexed databases (PubMed, Google-Scholar, Scopus, EMBASE, and Web of Knowledge) were searched till September 2017. Titles and abstracts of studies identified using the above-described protocol were independently screened by 2 authors. Full-texts of studies judged by title and abstract to be relevant were independently evaluated for the stated eligibility criteria. Nine studies were included. Six studies showed that ICSI compromised bone area contact around implants. In 4 studies, peri-implant bone mineral density was significantly higher in the control group than among subjects exposed to ICSI. For the effects of ICSI on the osseointegration of dental implants, significant differences could be observed for bone-to-implant contact for test subjects in cancellous (Z=-4.08, p<0.001) and cortical bone (Z=-4.31, p<0.001) respectively. ICSI may negatively influence osseointegration of dental implants. It is imperative to educate patients about the negative effects of passive smoking on dental and systemic health.

Attitude and knowledge of family medicine practitioners towards the association between periodontal disease and obesity

OBJECTIVES

To assess the attitude and knowledge of family medicine practitioners (FMPs) towards the association between periodontal disease and obesity.

MATERIALS AND METHODS

A cross-sectional study was performed and a 13-item survey questionnaire was given to FMPs practicing in 12 different teaching hospitals in Karachi, Pakistan. The questions were aimed at exploring the knowledge of FMP's regarding the association of obesity and periodontal disease and their attitude towards the association of obesity and periodontal disease. Chi-square and Spearman co-efficient were conducted to compare subgroups and correlate factors with the knowledge score of FMPs.

RESULTS

A total of 314 questionnaires were completed (response rate = 92%). Median age of participants was 41 years and 57% were females. Almost 61% of FMPs answered all the knowledge questions correctly and 64% reported moderate understanding of the association between periodontal health and obesity. Nearly 73% FMPs inquired from obese patients regarding the periodontal disease and more than half (58%) refer patients to a dentist for evaluation. More than half of FMPs perform periodontal disease screening. Nearly all FMPs considered informing obese patients regarding periodontal disease as one of their roles.

CONCLUSIONS

FMP's play an important role in the early diagnosis, prevention and treatment of periodontal conditions in obese patients. More than two thirds of FMPs showed good knowledge of the association of obesity and periodontal disease. The attitudes of FMPs towards assessing and referring obese patients at a risk of having periodontal disease were reassuring.

Influence of implant location in patients with and without type 2 diabetes mellitus: 2-year follow-up

The aim of the present cross-sectional retrospective 2-year follow-up clinical study was to assess the influence of implant location on clinical and radiographic parameters around dental implants placed in patients with and without type 2 diabetes mellitus (T2DM). Twenty-seven patients with T2DM and 25 non-diabetic controls were included. Implants were classified into three zones according to their location: (1) anterior zone: implant/s replacing anterior teeth, (2) middle zone: implant/s replacing premolars, and (3) posterior zone: implant/s replacing molars. Peri-implant bleeding on probing (BOP), probing depth (PD), and crestal bone loss (CBL) were measured. P-values less than 0.05 were considered statistically significant. The mean age of patients with T2DM was 42.5 years and that of non-diabetic controls was 40.6 years. The mean fasting blood glucose levels of patients with and without T2DM were 74.5mg/dl (66-80mg/dl) and 82.5mg/dl (79-88.1mg/dl), respectively. The mean duration of T2DM was 4.3 years. There was no significant difference in BOP, PD, or CBL around implants placed in any of the zones in the jaws of patients with and without T2DM. There is no influence of implant location on clinical and radiographic parameters around dental implants placed in patients with and without T2DM.

Marginal adaptation of class II resin composite restorations using incremental and bulk placement techniques: an ESEM study

This in vitro study compared marginal gap formation in class II resin composite restorations. Forty caries-free extracted molars were prepared in a standardized manner for class II restoration by one of four methods: bulk- or incrementally-placed light-activated resin composite (Amelogen), and bulk- or incrementally-placed chemically activated composite (Rapidfill). The restored teeth, after finishing and polishing, and thermocycling, were examined using environmental scanning electron microscopy. Marginal gap measurements at predetermined facial and lingual margin sites showed no significant differences between the two sites within any of the groups. Both the light- and the chemically-activated restorations showed no significant differences in mean marginal gap sizes whether they were placed by incremental or bulk techniques. Amelogen restorations placed by both methods had significantly larger margin gaps than those of each of the Rapidfill groups (P<0.05). Thus, although method of placement of a given material had no significant effect on the quality of marginal adaptation, both of the chemically activated resin composite restorations produced significantly smaller marginal gaps than both the bulk- and incrementally-placed light-activated composites.

Effect of increased maxillo-mandibular relationship on isometric strength in TMD patients with loss of vertical dimension of occlusion

The effect on isometric strength of the shoulders and limbs while biting in habitual occlusion, on a bite-elevating appliance and on a placebo appliance was analyzed. Twenty female volunteer patients, presenting with temporomandibular pain dysfunction syndrome and obvious loss of vertical dimension, served as subjects. All were weaker to the manual application of the isometric Deltoid Press (IDP) when biting, as opposed to maintaining the mandible in an unsupported rest position. Two intraoral appliances were fabricated for each subject: a bite-elevating appliance (BEA) set by a functional criterion of peak strength to the IDP and a placebo appliance which did not interfere with occlusion but was "set" with a mock IDP procedure. Testing was carried out by the Neuromuscular Research Testing Laboratory of the Neurology Department of Tufts New England Medical Center. Testing was independent of the dentist who fabricated and set the appliances. A standard neuromuscular test with the Maximal Voluntary Isometric Contraction apparatus was used to assess strength of right and left shoulder, elbow and knee flexion and extension as is routinely performed with all neuromuscular disease patients. Twelve strength tests were carried out for each of three conditions: 1. Baseline-biting in habitual occlusion; 2. Elevated-biting on the BEA; and 3. Placebo-biting with the placebo appliance inserted. The order of conditions 2 and 3 was counterbalanced without knowledge of the subjects. Twelve repeated measures ANOVAs (each subject as their own control) were conducted for each of the 12 strength measures. All F-tests indicated a significant main effect for treatment differences (p < 0.0001). Mean strength biting on the BEA was consistantly greater (p < 0.001) than Baseline or Placebo strength. Baseline and Placebo condition were equivalent. These findings confirmed previous observations at this TMD Center: individuals with loss of vertical dimension of occlusion respond to a bite raising appliance by increased isometric-strength.

Listeria monocytogenes meningitis complicated by symptomatic spinal subarachnoid cysts

We report the case of a man who developed signs of compression of the spinal cord in the dorsal region over a year after treatment of Listeria monocytogenes meningitis. He proved to have mild hydrocephalus and a number of subarachnoid pouches compressing the upper dorsal cord. Insertion of a ventriculo-peritoneal shunt caused clinical improvement. We believe that this was caused by relief of tension in the spinal cysts rather than any reduction in ventricular size.