Xenogeneic collagen matrix for periodontal plastic surgery procedures: a systematic review and meta-analysis.

Several clinical trials describe the effectiveness of xenogeneic collagen matrix (XCM) as an alternative option to surgical mucogingival procedures for the treatment of marginal tissue recession and augmentation of insufficient zones of keratinized tissue (KT). The aim of this systematic review and meta-analysis was to evaluate the clinical and patient-centred outcomes of XCM compared to other mucogingival procedures. Applying guidelines of the Preferred Reporting Items for Systematic Reviews and Meta analyses statement, randomized controlled trials were searched for in electronic databases and complemented by hand searching. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool and data were analysed using statistical software. A total of 645 studies were identified, of which, six trials were included with 487 mucogingival defects in 170 participants. Overall meta-analysis showed that connective tissue graft (CTG) in conjunction with the coronally advanced flap (CAF) had a significantly higher percentage of complete/mean root coverage and mean recession reduction than XCM. Insufficient evidence was found to determine any significant differences in width of KT between XCM and CTG. The XCM had a significantly higher mean root coverage, recession reduction and gain in KT compared to CAF alone. No significant differences in patient's aesthetic satisfaction were found between XCM and CTG, except for postoperative morbidity in favour of XCM. Operating time was significantly reduced with the use of XCM compared with CTG but not with CAF alone. There is no evidence to demonstrate the effectiveness of XCM in achieving greater root coverage, recession reduction and gain in KT compared to CTG plus CAF. Superior short-term results in treating root coverage compared with CAF alone are possible. There is limited evidence that XCM may improve aesthetic satisfaction, reduce postoperative morbidity and shorten the operating time. Further long-term randomized controlled trials are required to endorse the supposed advantages of XCM.

Removable prosthodontic services, including implant-supported overdentures, provided by dentists and denturists.

The aim of this study was to evaluate the provision of removable prosthodontic services, including implant-supported overdentures, by dentists and denturists. A structured questionnaire was mailed to 474 randomly chosen dentists and 156 denturists registered to practise in New Zealand. Information was sought on the range of removable prosthodontic services provided (including implant-supported overdentures) and the professional fees charged for them. From 410 respondents, there was an overall response rate of 67.43%; 290 came from the dentists (males 78.6%, n = 228; females 21.48%, n = 62) and 120 from denturists (males 91.7%, n = 110; females 8.3%, n = 10). Most respondents were over 40 years of age, with one in three denturists (but only one in seven dentists) over 60 years of age. The extent of removable prosthodontic services varied. One-third of dentists referred complete denture patients and denturists referred a similar number of immediate denture cases. Denturists' complete denture, immediate denture and single reline prices were generally lower than those from dentists. Removable partial denture prices were similar. Implant-supported overdentures were recommended for edentulous patients by one-third of the dentists and three out of four denturists. Forty per cent of denturists (but only 10% of dentists) charged

Relative effectiveness of powered and manual toothbrushes in elderly patients with implant-supported mandibular overdentures.

AIM: The aim of this study was to compare the clinical effectiveness of a powered toothbrush (Braun Oral-B Plaque Remover 3-D) and a manual soft toothbrush (Oral-B Squish-grip brush) for the control of supragingival plaque and soft tissue inflammation around implants supporting mandibular overdentures. MATERIAL AND METHODS: The study sample involved 40 edentulous subjects, aged 55-80 years, having 2 unsplinted mandibular implants supporting a complete removable overdenture opposed by a maxillary complete denture. In this single-blinded, randomised, cross-over clinical trial, two 6-week experimental phases were separated by a 2-week wash-out period. 2 weeks prior to each experimental phase (pre-entry visits), implant abutments were polished to remove all plaque and a standardised instruction in the use of the toothbrush was given. Modified plaque and bleeding indices were recorded at the start and end of each experimental period. Mean index scores at each phase were analysed using paired t-test, and the mean number of sites showing a change in plaque or mucositis were compared using the Mann-Whitney U-test. Combined data from 2 different implant systems were considered after controlling for implant type. RESULTS: Only minor changes in plaque and bleeding scores were observed following the two test periods. There were no statistically significant differences between the manual and powered toothbrushes. CONCLUSION: Manual and powered brushes were found to be of comparable efficacy with regard to improvement in peri-implant bleeding and plaque indices.

One-year prospective evaluation of the early loading of unsplinted conical Brånemark fixtures with mandibular overdentures immediately following surgery.

BACKGROUND: Prospective evaluation of the early loading of unsplinted Brånemark implants with mandibular overdentures opposing conventional dentures is not evident in the implant-related literature. PURPOSE: To clinically evaluate progressive and early loading of 20 unsplinted conical Brånemark implants in edentulous mandibles with overdentures. MATERIALS AND METHODS: Ten edentulous patients all had two conical Brånemark implants placed in the anterior mandible with mandatory primary stability with bicortical anchorage. Ball abutment connection was performed simultaneously. Previously constructed conventional mandibular dentures were temporarily relined with tissue conditioner postoperatively and worn with moderation for the first 2 weeks to allow progressive loading. Early loading of the implants followed after 2 weeks, with inclusion of the respective matrices in the mandibular dentures, using a definitive reline procedure. RESULTS: All patients successfully functioned with their mandibular implant overdentures from 2 to 52 weeks postoperatively. Mean marginal bone loss was within established criteria for success: 0.22 mm (SD = 0.48 mm) mesially and 0.30 mm (SD = 0.39 mm) distally on the conical implants. Mobility tests using the Periotest instrument became more negative, although not at statistically significant levels. Difficulties in the management of the peri-implant mucosa between surgery and loading at 2 weeks were observed in 40% of the patients. CONCLUSIONS: These preliminary 1-year results show that successful early loading of unsplinted conical Brånemark implants with mandibular overdentures is possible.

Inter-abutment and peri-abutment mucosal enlargement with mandibular implant overdentures.

A variety of terms have been used to describe changes in the oral mucosa around abutments underneath fixed and removable implant prostheses such as mucosal inflammation, peri-implant mucosal hyperplasia, gingival hyperplasia, hyperplastic tissue, mucosal proliferation, proliferative gingivitis and peri-implant mucositis. Although such terms have become part of the evidence-based literature, there is no histological evidence to support the descriptive terminology used by authors. The use of the alternative term mucosal enlargement for clinical observations underneath mandibular implant overdentures is proposed. Prospective and retrospective reports have failed to use similar criteria to measure periodontal parameters in relation to these mucosal changes, both in keratinized or non-keratinized tissues. Therapeutic remedies for mucosal enlargement are dictated by authors' opinions on the possible aetiology. This literature review, coupled with clinical observations during a 5-year prospective study, prompts this proposal of the term mucosal enlargement underneath splinted and unsplinted mandibular implant overdentures.

The outcome of implant overdentures from a prosthodontic perspective: proposal for a classification protocol.

PURPOSE: This article proposes a classification protocol for reporting the outcome of implant overdentures. MATERIALS AND METHODS: Review of the literature pertaining to postinsertion prosthodontic procedures for maxillary and mandibular implant overdentures revealed a wide range in the terminology used and methods of reporting outcome, usually as a result of the use of varying designs among different implant systems. A need for comparative evaluation of the prosthodontic success of implant overdentures was identified. RESULTS: An existing classification protocol for implant-fixed prostheses containing six objectively defined fields was modified for implant overdentures. This new protocol, which also uses the descriptive fields of success, survival, unknown, dead, and retreatment (repair or failure), provides a method whereby postinsertion prosthodontic procedures and subsequent time to retreatment can be quantified regardless of design, method of attachment, or implant system. A ratio method for identifying prosthodontic treatment cost effectiveness of implant overdentures is included. CONCLUSION: This protocol could assist clinicians in their choices of implant overdenture therapy by providing accurate comparisons of varying implant overdenture systems and designs, and by identifying prosthodontic treatment cost effectiveness.

One-stage operative procedure using two different implant systems: a prospective study on implant overdentures in the edentulous mandible.

BACKGROUND: Evidence-based reports are needed to support the application of a one-stage surgical protocol for unsplinted implants supporting mandibular overdentures. PURPOSE: To examine the feasibility and success of using two different dental implant systems (originally designed for two-stage operative technique) using a one-stage operative procedure in patients being rehabilitated with implant mandibular overdentures. MATERIALS AND METHODS: The study sample involved 24 edentulous subjects (aged 55-80 yr) randomly allocated to two different implant systems, one with a machined titanium implant surface (Steri-Oss, Nobel Biocare, Göteborg, Sweden) and the other with a roughened titanium surface (Southern Implants, Ltd., Irene, South Africa). Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all patients, using a standardized one-stage surgical and prosthodontic procedure. Primary stability and bicortical anchorage of the implants was mandatory before healing abutments were connected at the time of implant placement. Implant overdentures and their respective matrices were inserted following a standard 12-week healing period. Data relating to mobility tests, radiographs, and peri-implant parameters were documented at 12, 16, and 52 weeks after surgery. RESULTS: A success rate of 95.8% for the Steri-Oss and 100% for the Southern Implants was found, without any statistically significant differences in the marginal bone loss. Significant changes in Periotest values were observed for both types between 12 and 52 weeks (p < .001). Minor changes were observed in the peri-implant parameters evaluated. CONCLUSIONS: These preliminary findings show a successful application of this one-stage approach for unsplinted implants supporting mandibular overdentures with Steri-Oss and Southern Implant Systems.

The prosthodontic maintenance requirements of mandibular mucosa- and implant-supported overdentures: a review of the literature.

PURPOSE: This article presents a critical review of the literature on the prosthodontic maintenance requirements of mandibular mucosa- and implant-supported overdentures. MATERIALS AND METHODS: A search of the literature produced 35 papers pertaining to prospective and retrospective studies. The relationship of these prosthodontic maintenance requirements to the axis of rotation treatment concept was examined. RESULTS: More often than not, 2 anterior mandibular implants either splinted (round or ovoid bars) or unsplinted (balls or magnets) have been used to evaluate this prosthodontic follow-up. Wide variation existed in the categories used for prosthodontic complications. Although principally related to alterations of overdenture contour and aspects of patrix and matrix maintenance, they also provide subjective information on relines and the rationale for avoiding overdenture fractures. These prosthodontic maintenance requirements undoubtedly have a direct impact on the time to retreatment of mandibular mucosa- and implant-supported overdentures. CONCLUSION: There appears to be a need for a more uniform, standardized categorization with criteria for determining prosthodontic success, in terms of maintenance requirements and complications, for mandibular mucosa- and implant-supported overdentures. Controlled prospective evaluations of exact prosthodontic maintenance requirements of mandibular overdentures using different systems are lacking and encouraged. There is also an absence of prospective studies on such maintenance requirements of mandibular overdentures using multiple round bars on 3 or 4 implants.

Mandibular implant-supported overdentures: a prospective evaluation of the burden of prosthodontic maintenance with 3 different attachment systems.

PURPOSE: A prospective study on mandibular implant-supported overdentures using more than 2 Brånemark implants splinted with multiple round bars evaluated a hypothesis that unnecessary prosthodontic maintenance would result from the contravention of accepted biomechanical principles. MATERIALS AND METHODS: A randomized prospective trial on 59 edentulous patients details prosthodontic maintenance and complications of 52 mandibular overdentures (11 unsplinted, 41 splinted) over a 3-year period. RESULTS: Prosthodontic maintenance was greater in the first year than in subsequent years, regardless of design. Comparison between the splinted designs with round bars revealed no statistically significant difference with either retentive clip activation or fractures. More than 70% of the retention clips in the 2-implant (single round bar) design needed activation, as compared to 44% of those with the 3-implant (double round bar) or 4-implant (triple round bar) design. Retention clip fracture occurred in 30% of patients with 3 or 4 implants and 16% of those with 2 implants. Relining the overdentures, regardless of design, revealed an excessive maintenance burden in 40% of overdentures. Remaking of overdentures was necessary in 21% of patients. CONCLUSION: Multiple round bars splinting 3 or 4 implants can still be a treatment concept in mandibular overdenture treatment. Results from prospective evaluation of this design indicate less prosthodontic maintenance of clip activation but more clip fractures than with 2 implants splinted with single round bars, although not at statistically significant levels.

Standardization of radiographs for mandibular implant-supported overdentures: review and innovation.

Radiographic monitoring of marginal peri-fixture bone is mandatory during prospective evaluation of different dental implant systems. Unyielding, uni-directional focus towards identifying the credibility of implant-supported overdenture therapy for the management of the edentulous predicament, has often neglected correct standardization of follow-up radiographs. Techniques for truly accurate location of film-holding devices have often not been applied to both unicentre and multicentre reports on mandibular implant-supported overdentures using Brånemark implants. An innovative improvement on existing methods using conventional and custom-made components, shows a procedure to accurately and simply standardize follow-up radiographs, for both free-standing and bar designs for mandibular implant-supported overdentures.

General dental practitioners' perceptions of removable prosthodontics in the undergraduate curriculum.

The undergraduate dental curriculum is undergoing rapid change and revision in dental schools worldwide. Decreasing edentulism, the advent of the clinical dental technician, and advances in technology (such as dental implantology) have led to changes in patient management and treatment options for general dental practitioners in New Zealand. The current undergraduate removable prosthodontic curriculum has seen very little change in past years at the School of Dentistry, University of Otago, and is under review to facilitate the teaching of general dental practice in the Final Year. A questionnaire-based survey of 150 general dental practitioners (response rate 74.6 percent) supported modification of the existing removable prosthodontics curriculum to improve its relevance to modern general dental practice. Integration of fixed and removable prosthodontic teaching was recommended.

Implant-supported prostheses in patients with Sjögren's syndrome: a clinical report on three patients.

Implant-supported prostheses offer a solution to the problems experienced by edentulous patients with Sjögren's syndrome. These patients often find it very difficult, if not impossible, to wear conventional complete dentures. Three clinical reports provide an insight into some of the difficulties involved in treating patients afflicted with this complex multifactorial disease using the Brånemark system.

Multi-planar and cross-sectional oblique scanning (CT) in implant surgery.

A comprehensive clinical examination followed by a radiographic assessment of the edentulous areas is a prerequisite to placing dental implants. Although radiographic assessment of the mandible is accurate using plain film radiography this is not so for the maxilla for which computed tomography is often necessary. In this study patients requiring the placement of maxillary implants were referred for multi-planar cross-sectional oblique and panoramic computed tomography (CT scan) in addition to standard radiographic views. After interpretation of the CT scans patients could be categorized into two groups. One group comprised those patients who could be treated with a standard protocol for implant placement; the second group required augmentation procedures to supplement bone volume. After implant placement, a minimum healing period of 24 weeks was adhered to prior to placing healing abutments. By 27 months 95.5 per cent of Brånemark System fixtures were osseo-integrated.

Effects of quinidine versus procainamide on the QT interval.

Eighteen patients were given quinidine and procainamide separately to evaluate whether prolongation of the QT interval by type Ia antiarrhythmic agents is a drug-specific phenomenon. Doses were titrated to achieve standard trough therapeutic levels of quinidine (2 to 5 micrograms/ml) and procainamide (4 to 12 micrograms/ml). In 16 of the 18 patients, the increase in corrected QT interval (QTc) was greater with quinidine than with procainamide, averaging 78 +/- 10 ms (+/- standard error of the mean) with quinidine and 39 +/- 7 ms with procainamide (p less than 0.001). The greater degree of QTc prolongation with quinidine than with procainamide was not due to differences in sinus cycle length, QRS duration, serum potassium level or concomitant drug therapy. Differences in relative drug level did not appear to account for the greater effect of quinidine. Thus, at frequently used plasma levels, quinidine prolongs QTc to a greater degree than does procainamide. This effect does not appear to be due to the comparison of "nonequivalent" drug levels.