Titanium versus zirconia complete arch implant-supported fixed prostheses: A comparison of plaque accumulation.

STATEMENT OF PROBLEM: Complete arch implant-supported zirconia prostheses appear to have less plaque accumulation than titanium prostheses, but a comparison of the materials and the possible influence on the adjacent soft tissue is lacking. PURPOSE: The purpose of this clinical study was to compare the plaque accumulation and soft-tissue inflammation of complete arch implant-supported fixed maxillary prostheses fabricated with either a titanium framework or monolithic zirconia. MATERIAL AND METHODS: Twenty participants with a complete arch implant-supported fixed maxillary prosthesis were enrolled in the study. The participants were divided into 2 groups according to the prosthesis material, titanium (Ti) or zirconia (Zir). The prosthesis had to have been in function for at least 6 months, and participants were examined during at least 3 maintenance appointments at 3-month intervals. Clinical information collected in each appointment included standardized photographs to record the Plaque Area Index (PAI) of the intaglio surface of the prosthesis; clinical parameters including modified Plaque Index (mPI), modified Bleeding Index (mBI), implant mobility (MOB), probing depths ≥5 mm (PD), suppuration (SUP), keratinized tissue band ≥2 mm (KT), and an intraoral photograph of the maxillary arch without the prosthesis to evaluate the redness of the soft tissues. RESULTS: MOB was not present at any implant at any time point. SUP could not be analyzed because it was an infrequent finding. Both groups exhibited significant increases in mBI over time. No significant differences were observed for PD between the groups at any time point. Implants in the Ti group had significantly higher KT values than those in the Zir group; levels remained constant over time for both groups. Zirconia prostheses had slightly lower PAI levels than Ti prostheses. The PAI in the Zir group significantly decreased over time (P=.035); in the Ti group, they remained constant (P=.45). Higher PAI levels were correlated with increased levels of erythema; both groups had a significant decrease in erythema values over time (P=.04). CONCLUSIONS: Zirconia complete arch implant-supported fixed maxillary prostheses displayed a significant decrease in plaque accumulation in individuals who had received periodic maintenance and oral hygiene instructions. Ti prostheses had significantly higher plaque levels than zirconia prostheses at all time points, which was not reduced by maintenance and oral hygiene measures. The present study suggests that patients receiving zirconia prostheses respond well to plaque control measures, while plaque control for those with titanium prostheses may be more challenging.

An in vivo comparison of wound healing characteristics of two commercial acellular dermal matrices.

OBJECTIVES: Many acellular dermal matrices (ADMs) are available for use in periodontal surgical procedures. However, few studies exist evaluating their in vivo healing properties. The objectives of this study were to compare the wound healing and remodeling of two ADMs used for gingival augmentation procedures in the rat model. MATERIALS AND METHODS: This was a nonrandomized controlled split-mouth study. Envelope flaps were surgically created in the maxillary quadrants of 24 Sprague Dawley rats. Each received either (a) AlloDerm Regenerative Tissue Matrix, or (b) OrACELL. Gingival tissue from one mandibular quadrant served as the untreated control. Six male and six female rats were treated for 7 or 21 days. Biopsies were processed for histologic analysis (H&E, Picro-sirius red, Verhoeff's solution) or RNA analysis (RT-PCR) to analyze the expression of type I collagen (Col1a1), fibronectin (Fn-1) and VEGF-A (Vegf-A). RESULTS: There was a greater density of fibroblasts in OrACELL compared to AlloDerm at both timepoints. There was a greater density of elastin present in AlloDerm compared to OrACELL at 7 days but no differences at 21 days. There were no differences between test groups in the percentage of birefringent collagen or in the expression of Vegf-A or Fn-1. At 7 days, there were significantly more fibroblasts for males in the OrACELL group compared to females. At 21 days, there was a significantly greater expression of Col1a1 for males in the OrACELL group compared to females. CONCLUSIONS: Early wound healing and remodeling of OrACELL appeared to occur more rapidly than AlloDerm and was accelerated in male rats. Whether these results have clinical implications for soft tissue grafting procedures in humans remains to be determined.

The Association Between Occlusal Status and the Soft and Hard Tissue Conditions Around Single-Unit Dental Implants.

The occlusal status of single-unit dental implants were evaluated using traditional and computerized methods. The type of occlusal contact in maximum intercuspation and the presence of occlusal contacts on the implant during eccentric movements were recorded. A digital sensor was used for computerized analysis of occlusion. Forty-four patients with 74 implants were included. Twenty-nine implants (39%) presented with "heavy" occlusal contacts, 40 implants (54.1%) presented with "light" contacts, and 5 implants (6.8%) presented with "no contact." No statistically significant association was found between the occlusal status and any of the soft and hard tissue condition variables (P > .05).

Laser Assisted Non-surgical Periodontal Therapy: A Double Blind, Randomized Clinical Trial.

The objective of this study was to examine potential benefits of using laser therapy for secular decontamination in conjunction with scaling and root planing in the treatment of chronic periodontitis. The study was performed on 173 teeth in 14 patients in a split-mouth design, one side received scaling and root planing followed by laser therapy using a carbon dioxide (CO2) laser with an ablative handpiece (test group); the contralateral side received scaling and root planing without laser (control group). Clinical and laboratory parameters were evaluated prior to treatment and at 3 and 6 months following therapy; clinical measurements were performed by two blinded examiners. The clinical parameters included measurement of gingival recession (REC), bleeding on probing (BOP), clinical attachment level (CAL), pocket depth (PD), furcation involvement (FUR), and tooth mobility (MOB). Laboratory testing to determine the levels of periodontal pathogens was performed using PCR techniques. The results of the study revealed statistically significant differences in clinical and laboratory parameters at 3 and 6 months after therapy for both test and control groups, but no significant difference was observed between the two groups. However, sites receiving laser therapy tended to show a greater decrease in probing depths, gain in clinical attachment level, and reduced bacterial levels. In conclusion, the overall results of the study suggest a potential benefit of using laser therapy in conjunction with scaling and root planing for the treatment of chronic periodontitis.

The Role of Occlusion in the Dental Implant and Peri-implant Condition: A Review.

Dental implants have become a widely used dental treatment approach. It is important to identify factors that can be detrimental to dental implants and the peri-implant complex. There is controversy regarding whether occlusion plays a role in the implant and peri-implant condition. The present study aims to review the scientific literature regarding this topic. Animal and human studies, and previous reviews on the topic are included and presented. There is a wide heterogeneity among study designs. Several articles demonstrated that occlusion and occlusion overload could detrimentally affect the peri-implant condition, while other articles did not support these results. More studies are needed to help understand the mechanisms by which occlusion might play a role in the peri-implant condition.

Ridge preservation for implant therapy: a review of the literature.

Healing of the extraction socket after tooth removal involves retention of the blood clot followed by a sequence of events that lead to changes in the alveolar process in a three dimensional fashion. This normal healing event results in a minimal loss of vertical height (around 1 mm), but a substantial loss of width in the buccal-lingual plane (4-6 mm). During the first three months following extraction that loss has been shown to be significant and may result in both a hard tissue and soft tissue deformity affecting the ability to restore the site with acceptable esthetics. Procedures that reduce the resorptive process have been shown to be predictable and potentially capable of eliminating secondary surgery for site preparation when implant therapy is planned. The key element is prior planning by the dental therapist to act at the time of extraction to prevent the collapse of the ridge due to the loss of the alveolus. Several techniques have been employed as ridge preservation procedures involving the use of bone grafts, barrier membranes and biologics to provide a better restorative outcome. This review will explore the evidence behind each technique and their efficacy in accomplishing site preparation. The literature does not identify a single technique as superior to others; however, all accepted therapeutic procedures for ridge preservation have been shown to be more effective than blood clot alone in randomized controlled studies.

Use of a Carbon Dioxide Laser as an Adjunct to Scaling and Root Planing for Clinical New Attachment: A Case Series.

INTRODUCTION: Severe, chronic periodontitis (CP) is typically treated either with scaling and root planing (SRP) or surgical therapy in an effort to gain clinical attachment. The advantage of non-surgical therapy is decreased morbidity to the patient; however, the site typically heals by formation of a long junctional epithelium. The advantage of surgical therapy is access for debridement and the use of bone or bone substitutes in combination with a barrier membrane for epithelial exclusion. Compared with a non-surgical approach, surgical therapy is more invasive, and patient acceptance of treatment is typically more challenging. The use of lasers in dentistry appears to be rapidly increasing, as evidenced by the influx of new lasers into the dental market as well as numerous anecdotal reports of beneficial results with their use. CASE SERIES: This report presents a novel approach to the treatment of severe CP using a carbon dioxide (CO2) laser in combination with SRP. This study presents the findings of 17 patients (nine males and eight females, aged 34 to 71 years; mean age: 54 years) that were compared in a split-mouth design and followed for 3 months. To the best of the authors' knowledge, this is the first reported case series using a CO2 laser for de-epithelialization in combination with SRP for the treatment of CP. CONCLUSION: Sites treated with the CO2 laser tended to show a greater decrease in probing depths, greater amounts of recession, and greater gains in clinical attachment levels, but the results were not statistically significantly better than SRP alone.

A comparative study of root defect coverage using an acellular dermal matrix with and without a recombinant human platelet-derived growth factor.

BACKGROUND: The objective of this case series is to compare root defect coverage results and healing responses of bilateral recession defects treated with acellular dermal matrix (ADM) with and without recombinant human platelet-derived growth factor (rhPDGF). METHODS: Seventeen patients with 40 bilateral gingival recession defects were compared. Each defect was ≥2 mm and treated with ADM and a coronally advanced flap. Using split-mouth design, the control-side ADM was hydrated in sterile saline, whereas the test-side ADM was hydrated in rhPDGF. The patients were evaluated at 1 week, 1 month, 3 months, and 6 months. Standardized measurements were taken preoperatively at 3 and 6 months. Healing was clinically assessed at 1 week and 1 month post-surgically. RESULTS: Both test and control groups showed significant gain in root defect coverage over the 6-month period for all individuals, with the test group showing a 69.0% gain and the control group showing a 76.7% gain. Patients divided into Miller Class I and Class III defects were also found to have a significant gain in root defect coverage over 6 months. The test group showed 84.1% gain, and the control group showed 84.7% gain for Miller Class I defects. For Miller Class III defects, the test group showed 51.5% gain, and the control group showed a 60.8% gain. One week after surgery, 35% of the test group showed better healing, whereas 15% of the control group showed better healing. One month after surgery, 20% of the test group showed better healing, whereas 15% of the control group showed better healing. CONCLUSION: Based on the results of this case series, there were no statistically or clinically significant differences in root defect coverage, keratinized tissue, clinical attachment level, or clinical healing for treatment of root recession with a coronally advanced flap and ADM with and without rhPDGF.

Evaluation of the SEDline to improve the safety and efficiency of conscious sedation.

Brain function monitors have improved safety and efficiency in general anesthesia; however, they have not been adequately tested for guiding conscious sedation for periodontal surgical procedures. This study evaluated the patient state index (PSI) obtained from the SEDline monitor (Sedline Inc., San Diego, CA) to determine its capacity to improve the safety and efficiency of intravenous conscious sedation during outpatient periodontal surgery. Twenty-one patients at the periodontics clinic of Baylor College of Dentistry were admitted to the study in 2009 and sedated to a moderate level using midazolam and fentanyl during periodontal surgery. The PSI monitoring was blinded from the clinician, and the following data were collected: vital signs, Ramsay sedation scale (RSS), medications administered, adverse events, PSI, electroencephalography, and the patients' perspective through visual analogue scales. The data were correlated to evaluate the PSI's ability to assess the level of sedation. Results showed that the RSS and PSI did not correlate (r = -0.25) unless high values associated with electromyographical (EMG) activity were corrected (r = -0.47). Oxygen desaturation did not correlate with the PSI (r = -0.08). Satisfaction (r = -0.57) and amnesia (r = -0.55) both increased as the average PSI decreased. In conclusion, within the limits of this study, PSI appears to correlate with amnesia, allowing a practitioner to titrate medications to that effect. It did not provide advance warning of adverse events and had inherent inaccuracies due to EMG activity during oral surgery. The PSI has the potential to increase safety and efficiency in conscious sedation but requires further development to eliminate EMG activity from confounding the score.

A comparative study of root coverage using two different acellular dermal matrix products.

BACKGROUND: Gingival recession remains an important problem in dental esthetics. A new dermal matrix material has been introduced, but its effectiveness has not been studied and compared to current dermal matrix material. The aim of this study is to compare the healing associated with a coronally advanced flap for root coverage in areas of localized tissue recession when using Alloderm (ADM) and Puros Dermis (PDM). METHODS: A split-mouth design was used for this study, with 52 contralateral sites in 14 patients with Miller Class I or III facial tissue recession. Twenty-six sites were treated with coronally advanced flap using PDM, and 26 sites were treated with coronally advanced flap using ADM, all followed for 6 months. Clinical measurements of vertical recession, keratinized tissue, probing depths, and attachment levels were made initially, at 3 months, and at 6 months. RESULTS: Both groups had significant improvement in the amount of recession coverage with means of 2.83 mm for the PDM and 3.13 mm for the ADM. The percentage of root coverage was 81.4% for the PDM and 83.4% for the ADM; differences between the materials were not statistically significant. CONCLUSIONS: Based on the results of this study, there was no statistical or clinical difference in the amount of root coverage, probing depth, or keratinized tissue in coronally advanced flaps for root coverage with either of the two acellular dermal matrix materials. Both materials were successful in achieving root coverage.