Effect of implant support for prostheses on electromyographic activity of masseter muscle and jaw movement in patients after mandibular fibula free flap reconstruction.

PURPOSE: Dental implants are used to stabilize, support, and retain prostheses in the mandible following fibula free flap reconstruction. A previous longitudinal prospective study showed that an implant-supported prosthesis (IP) provided additional improvement in masticatory performance compared to a conventional prosthesis (CP). Therefore, in this paper, the impact of implant retention and support of mandibular prostheses on neuromuscular function is reported via a within-subject analysis. MATERIALS AND METHODS: Forty-six participants were enrolled in the study. Prosthetic treatment with a CP was completed in 33 subjects following oromandibular resection and fibula free flap reconstruction. Twenty-five subjects completed evaluation of the CP after an adaptation period. Standardized masticatory tests with peanuts were given to subjects on the defect and nondefect chewing sides. Electromyography (EMG) of masseter muscles and jaw movement was performed and recorded simultaneously in 19 of these subjects. IP treatment was then completed in 16 of these subjects, and 15 of them participated in the IP evaluation after an adaptation period. Of these 15 subjects, 13 completed EMG and jaw movement recordings for both CP and IP. RESULTS: EMG activity of the defect-side masseter muscle increased significantly from CP to IP conditions when chewing on either side, but no significant change was found for nondefect-side muscle activity. Jaw movement parameters showed no significant changes from CP to IP. CONCLUSION: In patients restored with mandibular fibula free flap reconstruction, implant support for mandibular prostheses has the benefit of permitting greater muscle effort on the defect side, irrespective of the side on which the bolus is being chewed. The impact of an IP on jaw movements is limited.

Functional outcomes for clinical evaluation of implant restorations.

The functional outcomes related to treating patients afflicted with tooth loss are an important hallmark in substantiating prosthodontic intervention. The Oral Rehabilitation Outcomes Network (ORONet) conducted two international workshops to develop a core set of outcome measures, including a functional domain. The process followed the general format used in the Outcome Measures in Rheumatology (OMERACT) workshops to develop consensus for clinical outcome measures in arthritis research, which included: developing a comprehensive list of potential outcomes in the literature; submitting them to a filter for validity, clinical discrimination, and feasibility; and ranking those measures meeting all the filter criteria for relative value. The search was conducted to include functional assessments of speech, swallowing, mastication, nutrition, sensation, and motor function as they relate to dental implant therapies. This literature review surveyed 173 papers that produced some result of these descriptors in the functional domain. Of these, 67 papers reported on functional assessments and further defined objective and subjective outcomes. Many of these results were patient-perceived improvements in function, while others were objective assessments based on established methodologies and instruments. Objective evaluations of masticatory function and speech may meet criteria for validity and discriminability for selected interventions, but are generally not feasible for routine use in clinical care settings. The current recommendation is to employ a well-validated survey instrument that covers mastication and speech, such as the Oral Health Impact Profile (OHIP-14, short form), recognizing that patient perceptions of function may differ from objective ability.

Psychologic outcomes in implant prosthodontics.

Consensus regarding outcomes of the treatment of tooth loss, especially the psychologic outcomes, is needed to guide discovery of best practices and enable a better understanding of patient management for this chronic condition. This paper presents the findings of the ORONet Psychological Working Group for prosthodontics and aims to identify psychologic outcomes with properties deemed critical to meet clinical trial and clinical practice needs for the future. References obtained using a PubMed/Medline search were reviewed for clinical outcomes measures of interest. Clinical outcomes measures were judged relative to the criteria of truth, discrimination, and feasibility. Of the psychologic outcome measures identified in this systematic review, only the OHIP-14 was thought to be suitable for use in general practice and multi-institutional outcome registries and clinical trials. Development of clinically useful psychologic outcomes for future use could benefit from developmental methods and tools outlined in the patient-related outcomes field of clinical care.

Economic outcomes in prosthodontics.

PURPOSE: A systematic literature review was conducted to identify the types of economic measures currently used in implant prosthodontics and determine the degree to which cost of care is considered in the context of any positive outcome of the care provided. MATERIALS AND METHODS: A literature search was conducted using the following set of terms plus some additional hand searching: "dental implants" (Mesh) AND ("cost") OR "maintenance" OR "healthcare policy" OR "access to care" OR "third party" OR "economic") AND (("1995/01/01"[PDat]:'2009/12/31"[PDat]) AND (Humans[Mesh]) AND (English[lang])). RESULTS: After a review of the 466 titles and abstracts identified by the search, 18 articles were accepted for further consideration, as some attempt at economic outcome measures was made. An additional four articles were identified by hand searching. The 22 accepted articles were grouped into four basic categories: (1) measure of costs of treatment (direct, indirect, and maintenance costs), (2) cost-effectiveness mathematical modeling applied to simulate the lifetime paths and cost of treatment, (3) cost-effectiveness analysis/cost minimization, and (4) willingness-to-pay, willingness-to-accept. Attempts at determining the costs of treatment varied widely. When the OMERACT filters were applied to the various measures it was felt that discrimination and/or feasibility was a problem for most of the current economic outcome measures. CONCLUSIONS: Measures of cost-benefit, cost-effectiveness, and cost-utility are currently the gold standard; however, feasibility of such analyses is an issue. Collaboration with health economists to guide future research is highly recommended.

Oral Rehabilitation Outcomes Network-ORONet.

The published literature describing clinical evidence used in treatment decisionmaking for the management of tooth loss continues to be characterized by a lack of consistent outcome measures reflecting not only clinical performance but also a range of patient concerns. Recognizing this problem, an international group of clinicians, educators, and scientists with a focus on prosthodontics formed the Oral Rehabilitation Outcomes Network (ORONet) to promote strategies for improving health based on comprehensive, patient-centered evaluations of comparative effectiveness of therapies for oral rehabilitation. An initial goal of ORONet is to identify outcome measures for prosthodontic therapies that represent multiple domains with patient relevance, are amenable to utilization in both institutional and practice-based environments, and have established validity. Following a model used in rheumatology, the group assessed the prosthodontic literature, with an emphasis on implantbased therapies, for outcomes related to longevity and functional, psychologic, and economic domains. These systematic reviews highlight a need for further development of standardized outcomes that can be integrated across clinical and research environments.

Clinical outcomes measures for assessment of longevity in the dental implant literature: ORONet approach.

The Oral Rehabilitation Outcomes Network (ORONet) Longevity Working Group undertook a search of the literature from 1995 to 2009 on randomized controlled trials related to longevity of osseointegrated implants. Outcomes measures used in these studies were identified and subjected to the OMERACT component criteria of truth, validity, and feasibility. Through this process, it was a challenge to identify clinical outcomes measures that fully met the criteria. An attenuated version of the component criteria was applied, and clinical measures were identified for implant outcomes, prosthetic outcomes, and indices. A recommendation on standardized reporting periods was also presented for future consideration. The endpoint of the evaluation process is to develop consensus on clinical outcomes measures that can be applied across broad populations for osseointegrated implant care. The present ORONet initiative represents a beginning toward continual improvement and consensus development for clinical outcomes measures for osseointegrated implants.

Mandibular fracture in conjunction with bicortical penetration, using wide-diameter endosseous dental implants.

Prosthodontic rehabilitation of a patient with an atrophic edentulous mandible presents a significant challenge in restoring esthetics and function. The purpose of this clinical report is to describe fracture of an atrophic edentulous mandible opposing maxillary natural dentition in association with endosseous dental implants. The patient received two wide-diameter implants in the anterior mandible for an implant-assisted mandibular overdenture, in which the implants penetrated the inferior border of the mandible for bicortical stabilization. Three months following implant placement surgery, the patient experienced pain, swelling, and intraoral purulent drainage around the right implant. Panoramic radiograph revealed a fracture of the mandible through the right implant site and signs of infection around the left implant. The implants were removed surgically, and open reduction and fixation of the fracture site were undertaken using a titanium bone fixation plate. This clinical report demonstrates that placement of wide-diameter implants in conjunction with bicortical penetration in a severely atrophic edentulous mandible can risk fracture of the mandible.

The frequency of replacement of dental restorations may vary based on a number of variables, including type of material, size of the restoration, and caries risk of the patient.

SUBJECTS: The authors analyzed the dental records of 2780 Navy (cohort 1 = 1078 entered the Navy in 1997) and US Marine Corps recruits (cohort 2 =1053 entered the USMC in 1999-2000; cohort 3 = 649 entered the USMC in 2002-2005). The records were reviewed at 16 US Navy dental treatment facilities at the following time periods: cohort 1, 2001; cohort 2, 2002-2003; and cohort 3, 2005-2006. The mean age of the subjects was 20 years, and 85% were men. Only posterior teeth (not third molars) with amalgam or resin-based composite (including glass ionomer restorations) were evaluated. Teeth that had been restored with more than one material and restorations that did not involve the occlusal surface were excluded. The minimum follow-up time was 2 years with at least 2 periodic exams following the initial exam. KEY EXPOSURE/STUDY FACTOR: The primary factor of interest was the type of restorative material (amalgam versus resin-based composite). Secondary factors included tooth number, number of restored surfaces (single or multiple), and caries risk of the patient. Caries risk status was defined using the Navy Dental Corps Oral Disease Risk Management protocol. MAIN OUTCOME MEASURE: The primary outcome measure of interest was the determination of the relative risk of replacement of an initially intact restoration during the subject's first years of military service. Restorations were classified as clinically acceptable or requiring replacement either as a result of new primary caries, secondary caries, defective restorations, or endodontic therapy. MAIN RESULTS: At the initial exam, 964 (15.2%) of the amalgam restorations and 199 (17.4%) of the resin-based composites required replacement and were excluded from further analysis. Of the remaining restorations, an additional 14.2% of the amalgam and 16.7% of the composite restorations required replacement during the observation period. The mean follow-up time was 3.0 years (cohort 1, 3.4 years; cohort 2, 3.1 years; cohort 3, 2.3 years). Replacement rates for resin-based composite restorations compared with amalgam were significantly higher owing to all causes (adjusted hazard ratio [HR], 1.28; P < .05) and for replacement owing to restoration failure (adjusted HR, 1.64; P < .01). Multiple surface restorations demonstrated higher rates of replacement than single surface restorations from all causes (adjusted HR, 1.39; P < .01) and for replacement of existing restorations (adjusted HR, 1.82; P < .01). High-caries-risk subjects experienced more than twice the risk of retreatment than did low-caries-risk subjects when considering all replacements (adjusted HR, 2.04; P < .01) and 50% higher risk of replacement of previously restored surfaces (adjusted HR, 1.48; P<.01) CONCLUSIONS: Approximately 30% of all posterior restorations required replacement either at the initial or subsequent exams during the observation period. The number of resin-based composite restorations requiring replacement was significantly higher than amalgam restorations. The authors concluded that because of the extra cost, time, and potential for increased frequency of replacement, posterior composite restorations should be limited to restorations of appropriate size and placed under meticulous restorative technique with strict adherence to manufacturer's instructions.

The social solution-denture esthetics, phonetics, and function.

Tooth loss and rehabilitation with dentures can have tremendous patient impact and social implications. In an image-conscious society, dentures restore a sense of normalcy and allow the patient the ability to interact with others. The most frequent denture complaints include chewing discomfort and objectionable esthetics and phonetics. Determining patient expectations and their influence on patient satisfaction with treatment is critical. Current evidence on functional outcomes, patient satisfaction, and cost-effectiveness of treatment with conventional dentures versus implants are important factors to consider during treatment planning for the edentulous patient. The purpose of this article is to review some exemplar literature for the successful treatment of the edentulous patient.

Optimization of maxillary obturator thickness using a double-processing technique.

Preservation of remaining structures is a primary goal of prosthetic rehabilitation. Continuously applied stresses on the remaining tissues from a large, heavy obturator jeopardize the health of the tissues, compromise the function of the prosthesis, and affect patient comfort. Various techniques have been described for hollowing the bulb of an obturator after processing to reduce its weight; however, access to the inner aspects of the bulb is limited, preventing adequate control of thickness of the walls. This article describes a double-processing technique for an obturator to optimize the weight and thickness of the bulb.

Maxillofacial restoration after head and neck tumor therapy.

Oral and pharyngeal cancers are among the leading cancer sites. Surgery, radiation, chemotherapy, or combination therapies are common treatment modalities. Radiotherapy and chemotherapy cause significant morbidity and long-term irreversible sequelae in the oral cavity. Surgical resection can be mutilating, disfiguring, and deeply affect self-image. Orofacial defects have unique limitations and challenges for both the surgeon and the maxillofacial prosthodontist. Microvascular surgical techniques and the use of osseointegrated implants improve the rehabilitation potential of the various head and neck defects. This article reviews current treatment modalities of tumor therapy, their consequences, and the restoration of maxillofacial defects.

Use of osseointegrated implants in the restoration of head and neck defects.

Osseointegrated implants can be applied to facilitate retention, stability, and support for facial and intraoral prostheses used to restore head and neck defects. At the University of California, Los Angeles, Maxillofacial Prosthetics Clinic, retrospective studies have indicated that in nonirradiated maxillectomy patients, implant survival rates are 82.6 percent. In mandibles reconstructed with fibula free flaps, survival rates are 94.6 percent. Similarly, high implant survival rates have been observed for most sites used to support facial prostheses. Cumulative six-year survival rates for auricular sites exceed 95 percent and for floor of nose sites, success rates exceed 87 percent. However, survival rates are low (53 percent) for implants placed in the frontal bone for retention of orbital prostheses and even lower for irradiated bone sites ranging from 63 percent in the maxilla to 27 percent in the orbit.

Masticatory and swallowing threshold performances with conventional and implant-supported prostheses after mandibular fibula free-flap reconstruction.

STATEMENT OF PROBLEM: Significant strides in microvascular surgical techniques allow predictable restoration of bony and soft tissue orofacial defects. In combination with prosthetic rehabilitation, varying degrees of improvement in esthetics, speech intelligibility, and swallowing have been noted; however, the relative impact of conventional and implant-supported prostheses on restoration of masticatory function are not known. PURPOSE: The purpose of this study was to determine whether conventional or implant-supported dental prostheses and current surgical reconstructive procedures restore patients' masticatory function to presurgical levels. MATERIAL AND METHODS: Of the 46 subjects enrolled in this study, 23 (7 edentulous and 16 partially dentate) completed conventional prosthesis (CP) treatment and masticatory evaluation, and of these, 15 (3 edentulous and 12 partially dentate) completed treatment and evaluation with an implant-supported prosthesis (IP). Standardized masticatory performance tests with peanuts and carrots as the test food were made on the defect and nondefect sides. Tests of swallowing threshold performance were made with carrots as the test food. Statistical analysis included repeated-measures analysis of variance (ANOVA) with post hoc Tukey HSD tests (alpha=.05). RESULTS: Masticatory function at entry was markedly compromised. Further performance declines were noted following surgery (PS) on both the defect and nondefect sides. Restoration with CP and IP produced improvements (significant for defect side only, P<.05) in performance over the PS interval and were not significantly different from performances at entry prior to surgery. In addition, the performance on the defect side with the IP was significantly greater than the performance with the CP (P<.001). CONCLUSION: Impairment in masticatory ability remains following free-flap reconstruction prior to prosthetic rehabilitation. Both CP and IP may provide improved masticatory ability, permitting patients to regain the functional level they possessed prior to surgical intervention. The IP may contribute to greater support and stability of the prosthesis, resulting in increased use for mastication and superior performance on the defect side compared to the CP.

Dental implant-assisted prosthetic rehabilitation of a patient with a bilateral maxillectomy defect secondary to mucormycosis.

Prosthodontic rehabilitation of patients with bimaxillary resection involving the maxillae, hard and soft palates, and paranasal sinuses presents a significant challenge in restoring speech, deglutition, mastication, and respiration. This clinical report describes the prosthodontic management of a young girl treated for leukemia who required a bilateral maxillectomy secondary to mucormycosis. Distraction osteogenesis, bone grafts, osseointegrated implants, and magnet attachments were used to provide retention, support, and stability of a large definitive obturator.

Efficacy of conventional and implant-supported mandibular resection prostheses: study overview and treatment outcomes.

STATEMENT OF PROBLEM: While surgical restoration of mandibular resections has advanced dramatically with free-flap techniques, oral function and patient perceptions of function, as well as treatment outcomes, often indicate significant impairment. PURPOSE: This longitudinal prospective study was designed to determine whether conventional prostheses (CP) or implant-supported prostheses (IP) and current surgical reconstructive procedures restore patients' oral functions and quality of life to their status prior to segmental mandibulectomy with immediate fibula free-flap reconstruction. Study design and implementation, characteristics of the study sample, treatment completion rates, and selected presurgical and postsurgical functional and perceptual outcomes are presented. MATERIAL AND METHODS: Forty-six subjects were enrolled. Longitudinal evaluations of medical and dental histories, oromaxillofacial examinations, questionnaires, and sensory and functional tests were planned before and after surgery and after CP and IP treatment. Sample characteristics are described with descriptive statistics and comparisons of subject responses to questionnaire items at entry and postsurgical intervals were made with Fisher exact tests (alpha=.05). RESULTS: Conventional prostheses were completed in 33 of 46 subjects, and 16 of 33 CP subjects were treated with IP. Reasons for noncompletion of IP were recurrent/metastatic disease (16), refusal of implant therapy (7), lost to follow-up (4), treatment with a reconstruction plate (1), excessive radiation at implant sites (1), and death (1). All 16 recurrences/metastases occurred within 13 months of surgery. Only 3 of the 58 implants placed in 17 participants were considered failures. One failed due to lack of integration 31 weeks following placement, and 2 were buried due to unacceptable positioning for prosthetic restoration during denture fabrication. The remaining 55 implants were successful at final evaluation, ranging from 58 to 123 weeks following implant placement (mean duration=78.9 +/- 16.0 weeks). CONCLUSIONS: While 72% (33/46) of the subjects enrolled were able and willing to complete treatment with CP, only 35% (16/46) completed IP treatment. Careful consideration must be given to selection of the type of prosthetic rehabilitation and the timing of implant placement if an IP is planned.

Treatment satisfaction with facial prostheses.

STATEMENT OF PROBLEM: Facial defects secondary to the treatment of neoplasms, congenital malformations, and trauma result in multiple functional and psychosocial difficulties. Prosthetic rehabilitation attempts to restore these facial disfigurements and may improve the level of function and self-esteem for these patients. However, a limited number of studies have evaluated the change in perceived quality of life after maxillofacial prosthetic rehabilitation. PURPOSE: The purpose of this study was to evaluate patients' perceptions of treatment with adhesive-retained and implant-retained facial prostheses and to assess differences in overall satisfaction with these 2 types of treatments. MATERIAL AND METHODS: In this study, a questionnaire with 28 items was administered for evaluation of perceptions of appearance, comfort, fit and irritation, reliability of retention, frequency of wear, ease of placement and removal, level of self-consciousness, and value of treatment. Subjects were categorized into 2 groups: adhesive-retained group (n=16) and implant-retained group (n=19). Comparisons were made for each item in the questionnaire using Fisher exact tests (alpha=.05). RESULTS: The implant group reported higher positive ratings on all 28 questionnaire items when compared with the adhesive group. Statistically significant (P<.05) differences between the implant and adhesive groups were noted for ease of placement and removal, frequency of wear at home, and quality of retention during various activities, such as home chores and when perspiring or sneezing/coughing. CONCLUSION: The implant-retained facial prosthesis offers significant enhancement over an adhesive-retained prosthesis with respect to ease of use and retention during a variety of daily activities, resulting in greater use of the prosthesis.

Osseointegrated craniofacial implants in the rehabilitation of orbital defects: an update of a retrospective experience in the United States.

STATEMENT OF PROBLEM: Since their introduction, craniofacial implants have been used in prosthetic rehabilitation of facial defects. The literature, however, indicates marked variability in outcomes using implants for the retention of orbital prostheses. PURPOSE: A multicenter report updating the experience in the United States with the use of craniofacial implants for prosthetic rehabilitation of orbital defects is presented. MATERIAL AND METHODS: Surveys were sent to clinicians at 25 centers where maxillofacial prosthetic treatment is provided to obtain retrospective data regarding patients who completed implant-retained orbital prosthetic rehabilitation. Data on implant placement location, radiation treatment history, and use of hyperbaric oxygen therapy were collected and assessed in relationship to implant survival over time. The Kaplan-Meier life table and Wilcoxon analyses (alpha = .05) were used to assess the significance of the findings. RESULTS: Ten centers responded, providing data suitable for statistical analysis on 153 implants placed to retain 44 orbital prostheses and followed for a mean period of 52.6 months. Forty-one implant integration failures occurred during this follow-up period, resulting in an overall integration survival rate of 73.2%. No significant relationship was found between radiation treatment history, hyperbaric oxygen therapy history, or implant placement location and implant survival. Individual responses revealed large variability between reporting centers in treatment outcomes. CONCLUSION: Craniofacial implants may offer marked benefits in the prosthetic rehabilitation of orbital defects when compared to conventional adhesive retention designs. However, questions remain regarding long-term predictability and the impact specific factors may have on treatment outcomes. Insufficient data is currently available from which to draw statistically meaningful conclusions. The establishment of a national database designed to acquire adequate data to assess treatment outcomes is recommended.