Posterior Bite Collapse: Guidelines for Treatment Based on Form and Function.

The clinical syndrome known as posterior bite collapse (PBC) consists of multiple, often pathognomonic factors that deviate from normal, or an occlusion wherein the posterior occlusion is compromised and may ultimately destroy the functional protective capacity of the entire dentition. Secondary clinical sequelae may include accelerated periodontitis progression, temporomandibular disorders (TMD), increasing mobility/fremitus, additional tooth loss, anterior flaring, and loss of occlusal vertical dimension. Etiologic factors may include tooth loss without replacement, orthodontic malocclusions and dentoskeletal disharmonies, periodontitis, accelerated retrograde occlusal/interproximal wear, severe caries, or iatrogenic and conformative dentistry. Not all PBC cases require treatment, but treatment is dependent upon the periodontium's stability and its ability to maintain its form and function. Treatment decisions can also be dependent upon periodontal health, caries, function, occlusion, TMD, esthetics, and phonetics. The purpose of this article is to provide general treatment guidelines based on form and function of the masticatory system for restoring a PBC case when treatment is necessary. This article does not discuss specific mechanics for restoring PBC cases.

Posterior Bite Collapse and Diagnostic Grading for Periodontitis.

The syndrome known as posterior bite collapse (PBC) has taken on multiple definitions over the years since its first introduction in 1964 by Morton Amsterdam and Leonard Abrams. In 2017, the World Workshop in the Classification of Periodontal and Peri-implant Diseases and Conditions proposed a staging system for periodontitis, defined by severity and extent of periodontal breakdown. Within this staging system, Stage IV periodontitis can include PBC. However, without a clear delineation regarding the clinical presentation or pathogenesis of PBC, this further obfuscates its definition. It is therefore the goal of this article to reexamine the original definition of PBC as defined by Amsterdam and Abrams, present an updated definition, and propose a clinical grading system of PBC to coincide with the 2017 staging of periodontitis.

Factors related to fear of falling among community-dwelling older adults.

AIMS AND OBJECTIVES: To investigate the relationship between age, gender, history of falls, balance and gait status, general health perception, activities of daily living and depression to fear of falling in community-dwelling older people in Danang, Vietnam. BACKGROUND: Fear of falling is a common and consequential psychosocial problem for older people and can lead to decreased quality of life. There is only limited research on fear of falling in Vietnam. DESIGN: This is a cross-sectional descriptive study. METHODS: One hundred fifty-three community-dwelling older people were recruited from seven communities of different districts in Danang. Data were collected using six instruments: a demographic questionnaire, the Fall Efficacy Scale-International, the General Health Perception questionnaire, the Barthel Activities of Daily Living, the Geriatric Depression Scale and the Timed Up and Go test. Data were analysed using descriptive and correlational statistics. RESULTS: The mean Fall Efficacy Scale-International score was 35, indicating a high level of fear of falling. ADLs, general health perception and Timed Up and Go were significantly and negatively related to fear of falling (rp  = -0·80, rsp  = -0·77 and rp  = -0·75, respectively). Age, depression and history of falls were significantly and positively related to fear of falling (rp  = 0·54, rp  = 0·45 and rs  = 0·39, respectively). Women were significantly more likely than men to have higher fear of falling (rpb  = -0·28). CONCLUSION: Fear of falling is more common in older people who are female, have a history of falls, have poor balance and gait status, have poor health perception, have greater ADL dependency, are depressed and, within the older people population, are older. Further research could examine additional correlates of fear of falling and develop/evaluate factor-specific intervention strategies to reduce fear of falling among community-dwelling older people. RELEVANCE TO CLINICAL PRACTICE: Understanding correlates of fear of falling among older Vietnamese people contributes to healthcare professionals' ability to develop effective cross-cultural and culture-specific interventions to reduce older people's fear of falling and to improve quality of life.

The use of a xenogeneic collagen matrix at the time of implant placement to increase the volume of buccal soft tissue.

The purpose of this study was to evaluate the efficacy of Mucograft (MG; a porcine-derived purified collagen membrane) to increase the thickness and height of the buccal soft tissue when placed at the time of implant placement in patients with thin or deficient keratinized tissue (KT). The primary endpoint of the study was the change in thickness and height of the buccal KT. Secondary endpoints included stability of the midbuccal soft tissue level; clinician rating of color, texture, and contour of treatment site; probing pocket depths (PPDs); assessment of satisfaction outcome; and patient assessment of pain/discomfort. Thirty-two patients were enrolled and 31 patients completed the study. There were no statistically significant (SS) differences between the MG and control groups for height measures. There was no SS difference for KT thickness (P = .117) between the groups at the final measurement (3 months postsurgery). However, there was an SS difference (P = .009) in favor of the MG group when comparing the difference in presurgical KT thickness to that 3 months postsurgery. Thus, MG was successful (compared to the control) in increasing the buccal KT. There were no SS differences between the groups for any of the other endpoints, including color, texture, contour, and pain assessment at any visit or successful outcome between the treatment group and the control. More cases and longer follow-up of implants placed with MG are needed to verify the results of this randomized prospective study.

Radiographic comparison of different concentrations of recombinant human bone morphogenetic protein with allogenic bone compared with the use of 100% mineralized cancellous bone allograft in maxillary sinus grafting.

The purpose of this study was to radiographically evaluate, then analyze, bone height, volume, and density with reference to percentage of vital bone after maxillary sinuses were grafted using two different doses of recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ACS) combined with mineralized cancellous bone allograft (MCBA) and a control sinus grafted with MCBA only. A total of 18 patients (36 sinuses) were used for analysis of height and volume measurements, having two of three graft combinations (one in each sinus): (1) control, MCBA only; (2) test 1, MCBA + 5.6 mL of rhBMP-2/ACS (containing 8.4 mg of rhBMP-2); and (3) test 2, MCBA + 2.8 mL of rhBMP-2/ACS (containing 4.2 mg of rhBMP-2). The study was completed with 16 patients who also had bilateral cores removed 6 to 9 months following sinus augmentation. A computer software system was used to evaluate 36 computed tomography scans. Two time points where selected for measurements of height: The results indicated that height of the grafted sinus was significantly greater in the treatment groups compared with the control. However, by the second time point, there were no statistically significant differences. Three weeks post-surgery bone volume measurements showed similar statistically significant differences between test and controls. However, prior to core removal, test group 1 with the greater dose of rhBMP-2 showed a statistically significant greater increase compared with test group 2 and the control. There was no statistically significant difference between the latter two groups. All three groups had similar volume and shrinkage. Density measurements varied from the above results, with the control showing statistically significant greater density at both time points. By contrast, the density increase over time in both rhBMP groups was similar and statistically higher than in the control group. There were strong associations between height and volume in all groups and between volume and new vital bone only in the control group. There were no statistically significant relationships observed between height and bone density or between volume and bone density for any parameter measured. More cases and monitoring of the future survival of implants placed in these augmented sinuses are needed to verify these results.

Histomorphometric comparison of different concentrations of recombinant human bone morphogenetic protein with allogeneic bone compared to the use of 100% mineralized cancellous bone allograft in maxillary sinus grafting.

The purpose of this study was to histomorphometrically evaluate the percentage of vital bone after grafting of maxillary sinuses using two different concentrations of recombinant human bone morphogenetic protein/acellular collagen sponge (rhBMP-2/ACS) combined with mineralized cancellous bone allograft (MCBA) and to compare the results to a control sinus grafted with MCBA only. Thirty-six sinuses in 18 patients had two of three of the graft combinations including: (1) control, MCBA only; (2) test one, MCBA + 5.6 mL of rhBMP-2/ACS (containing 8.4 mg of rhBMP-2); or (3) test two, MCBA + 2.8 mL of rhBMP-2/ACS (containing 4.2 mg of rhBMP-2). Histologic cores were taken 6 to 9 month following sinus augmentation. The results showed no statistically significant differences in vital bone between the two test groups compared to the control sinus group treated with MCBA alone. Future studies involving more cases and evaluating survival of implants placed in these augmented sinuses are needed to verify the results of this randomized prospective study.

Prosthetic management of minor soft tissue discrepancy due to facially placed implants: a report of two cases.

The facial soft tissue form of dental implants is influenced by a variety of biologic, surgical, and restorative factors. Implants and/or restorative components that are positioned facially present a challenge to created ideal facial soft tissue contours. The following case reports display how modification of the restorative components, namely, abutment and crown, will influence the soft tissue height and contour when minor tissue discrepancies exist due to nonideal implant placement.

Evaluating extraction sockets in the esthetic zone for immediate implant placement.

With the increasing demands of patients and the profession to maximize esthetic outcomes and minimize the number of procedures, clinicians must consider the use of immediate placement of implants into extraction sockets. Despite atraumatic extraction techniques, many cases present with a non-intact extraction socket, with bone deficiency in the coronal or apical aspect of the socket. In cases of immediate placement, an intact socket and guided bone regeneration procedures are often prerequisites to a successful esthetic outcome. In most cases, these grafting techniques can be performed at the time of immediate placement. Certain cases, however, have undergone such extensive bone and soft-tissue destruction that implants cannot be placed immediately and hard- and/or soft-tissue augmentation is required prior to implant placement. This article describes a classification system that considers both hard- and soft-tissue defects and the morphology of the extraction socket for immediate implant placement. Recommendations are made concerning the surgical technique required to treat the hard- and soft-tissue defects based on the socket morphology.

Distraction osteogenesis for ridge augmentation: prevention and treatment of complications. thirty case reports.

Distraction osteogenesis (DO) is the latest addition to the variety of alveolar ridge augmentation procedures used to increase the volume of bone prior to implant placement. Thirty DO procedures were performed in 30 patients using 17 intraosseous and 13 extraosseous devices to augment deficient alveolar ridges. Fifty-five implants placed in the distracted bone were followed for a period of 34 to 60 months after loading. Five implants failed, for a 90.9% success rate. Vertical augmentation ranged from 3.5 to 13.0 mm (average, 7.8 mm). At least one complication was encountered, requiring additional hard or soft tissue surgery, in each of the 30 reported cases. This paper reviews complications encountered in the DO-treated patients, suggesting solutions and measures to prevent these problems.

Therapeutic management for immediate implant placement in sites with periapical deficiencies where coronal bone is present: technique and case report.

A surgical approach is presented that enables the clinician to repair apical bony defects during immediate dental implant placement without compromising the integrity of the coronal bone and gingiva. This apical surgical technique retains the soft tissue form in the coronal aspect of the gingiva and allows the clinician to repair the apical bone loss or fenestration. A clinical case is presented to describe the technique. This technique is utilized in cases of immediate implant placement. After extraction of the tooth, the socket is evaluated. In cases where coronal bone is intact but apical bone is deficient, a flap technique is utilized to expose the defect. The implant osteotomy is prepared, and the implant is placed. A healing cap or gingival prosthetic component is connected. The bony defect is repaired with a bone graft and, where necessary, a membrane. The apicoectomy flap is sutured. The clinical results obtained using this technique will enable the clinician to accomplish the bone regenerative procedure without extending the flap to the coronal aspect of the socket during immediate implant placement. This technique assists in the maintenance and integrity of the soft tissue form, which is critical for optimal esthetic results.

A comparison of characteristics of implant failure and survival in periodontally compromised and periodontally healthy patients: a clinical report.

PURPOSE: This study compares implant survival and patterns of implant failure in periodontally compromised and periodontally healthy patients. MATERIALS AND METHODS: In a private periodontal practice, over a 13-year period, implants were placed in both periodontally compromised and periodontally healthy patients. Implants were classified in 5 different groups according to surface texture. Survival rates in each group were compared according to implant location, diameter, length, and phase of treatment. RESULTS: A total of 1,511 implants were placed in 334 patients. One hundred fifty-one of these patients, classified as periodontally compromised patients (PCP), received 923 implants. The remaining 183 patients, classified as periodontally healthy patients (PHP), received 588 implants. The overall survival rate for implants placed in the PHP group was 93.7%, compared to 90.6% in the PCP group. The survival rate of hydroxyapatite-coated implants was 92.6% in the PHP group and 81% in the PCP group. The survival rate of the turned-surface implants was similar in both groups. DISCUSSION: Two types of implant failure were identified. The first was failure of the implant to osseointegrate. This type of failure occurred early in treatment and appeared to be related to smooth-surface implants placed in bone of low density. Failures of this type were distributed equally between the PHP and PCP groups. The second type of failure was related to peri-implantitis. It was observed most often with implants with hydroxyapatite surfaces, occurred as the result of a progressive condition, and was most prevalent in the PCP group. CONCLUSION: Further long-term controlled investigations are needed to determine the influences of implant suface and host susceptibility on implant failure in both PHP and PCP.

Retrospective analysis of implant survival and the influence of periodontal disease and immediate placement on long-term results.

PURPOSE: The purpose of this study was to investigate the cumulative survival rates of dental implants placed in a private periodontal practice and the effects of periodontal disease and immediate placement on implant survival. MATERIALS AND METHODS: A retrospective chart review was conducted on 149 consecutive patients. Each patient had a single implant placed. For the purpose of analysis, patients were divided into 2 groups: those who were periodontally healthy and those who had periodontal disease. Implants were placed into available bone either immediately or after a healing period. All failed implants were removed and recorded. The effects of periodontal status and placement time on implant survival were evaluated using Cox proportional hazards regression and log-rank tests. RESULTS: Of the 149 implants in the study, 22 failed during the observation period. The 127 censored cases (i.e., implants that had not failed at the end of the observational period) were observed for a mean of 943 days (SD 932, range 35 to 4,030). Failed implants were observed for a mean of 722 days (SD 1,026, range 18 to 3,548). The presence of periodontal disease appeared to be associated with a greater failure rate, but there was no observed effect associated with time of placement. The percentages of censored immediate placement cases and delayed placement cases were nearly identical. Among the 77 implants associated with periodontal disease, placement time was not strongly associated with percentage censored. Forty-three of the 55 immediately placed implants (78.18%) and 18 of the 22 implants (81.18%) whose placement was delayed were censored. Both Cox proportional hazards regression and log-rank tests established that survival was adversely affected by periodontal disease (P < .05) but unaffected by time of placement (P > .50). The lower 1-sided 95% confidence limit for median survival time was 3,548 days for patients without periodontal disease and 1,799 days for patients with disease. DISCUSSION AND CONCLUSION: Implant survival was compromised by a history of periodontitis but not affected by immediate or delayed placement.

Extraction sockets and implantation of hydroxyapatites with membrane barriers: a histologic study.

The purpose of this pilot study was to investigate the effect on extraction socket healing when an absorbable hydroxyapatite (AH) and a nonabsorbable anorganic bovine bone mineral (ABB) covered with either an acellular dermal matrix allograft (ADMA) or expanded polytetrafluoroethylene (ePTFE) membrane barrier were left exposed to the oral cavity. Following tooth extraction, a total of 16 sockets in 15 patients with deficient buccal plates of > or =5 mm were randomly divided into 4 treatment groups: 1) AH covered with ADMA, 2) AH covered with an ePTFE membrane, 3) ABB covered with ADMA, and 4) ABB covered with an ePTFE membrane. Primary coverage was not attempted or obtained in any of the 16 treated sockets. Six to 8 months postextraction at the time of implant placement, histologic cores of the treatment sites were obtained. These cores were processed, stained with Stevenel's blue/van Gieson's picro fuchsin, and histomorphometrically analyzed. Vital bone, connective tissue and marrow, and residual graft particles were reported as a percentage of the total core. The mean vital bone was 34.5% (AH with ADMA), 41.7% (ABB with ADMA), 27.6% (ePTFE and AH), and 17.8% (ePTFE and ABB). The average percentage of vital bone in the 8 sockets covered with ADAMA was 38% compared with an average percentage vital bone of 22% in the 8 sockets covered with ePTFE membrane barriers. Because of the small number of specimens in the 4 groups, statistical analysis was not possible. However, in this pilot study, ADMA-covered sites resulted in more vital bone present 6 to 8 months postsocket treatment than obtained in the ePTFE-covered sites regardless of bone replacement materials used. Further research is warranted to see if these results show a similar difference in bone-to-implant contact after implant placement.

A computer-controlled anesthetic delivery system in a periodontal practice: patient satisfaction and acceptance.

BACKGROUND: Many dental patients are fearful about receiving intraoral injections of local anesthetic. In fact, many patients cite injections as their primary reason for avoiding dental treatment. In late 1997, however, a computerized local anesthetic delivery system was introduced to address the problems of pain and anxiety associated with these injections. The author initiated a year-long assessment study in which patients evaluated and rated injections administered with the computerized device as compared with previously administered standard injections. METHODS: One hundred and fifty randomly selected patients received local anesthesia delivered via the computer-controlled anesthetic delivery system. All patients had at some time received standard injections during treatment at the practice. Different types of injections were administered to all quadrants, enabling the researcher to qualify results according to injection type and location. Patient responses were recorded and evaluated to assess the levels of anxiety and pain associated with the computer-driven system. RESULTS: Overall, 71.4% of patients reported the experience to be superlative, positive, or somewhat positive. Results indicated that the system was highly preferred to traditional injection techniques, regardless of the arch and quadrant receiving the injection. Several factors may have contributed to this preference, including increased patient comfort, the nonthreatening appearance of the instrument, and the lack of residual facial numbness commonly associated with oral anesthetic injections. CLINICAL SIGNIFICANCE: By removing the discomfort associated with the dental injection, which is a common source of patient anxiety, use of the computer-controlled anesthetic delivery system may encourage patient acceptance of recommended periodontal treatment modalities.

Histological comparison of healing extraction sockets implanted with bioactive glass or demineralized freeze-dried bone allograft: a pilot study.

BACKGROUND: Various materials have been used immediately following tooth extraction to fill and/or cover the socket in an attempt to limit or prevent ridge resorption. The purpose of the present pilot study was to establish a reliable model to investigate the effect of various bone graft and bone replacement materials on extraction socket healing. This study also compared healing extraction sockets 6 to 8 months postimplantation of a bioactive glass (BG) or demineralized freeze-dried bone allograft (DFDBA) to an unfilled socket control (C). METHODS: Following tooth extraction, a total of 30 sockets in 19 patients were randomly divided into 3 treatment groups: 10 sockets received BG, 10 sockets DFDBA, and 10 sockets served as unfilled controls. Primary coverage was achieved by flap advancement over each socket. Six to 8 months postextraction at time of implant placement, histological cores of the treatment sites were obtained. These cores were processed, undecalcified sections prepared and stained with Stevenel blue/van Gieson's picric fuchsin, and histomorphometrically analyzed. Vital bone, connective tissue and marrow, and residual graft particles were reported as a percentage of the total core. RESULTS: A model system was described in humans and used to evaluate the healing response in the 3 treatment groups. Results concluded that mean vital bone present was 59.5% for BG-, 34.7% for DFDBA-, and 32.4% for C-treated sites. These differences were not statistically significant. However, the residual implant material was significantly higher in DFDBA-treated (13.5%) versus BG-treated sockets (5.5%). CONCLUSIONS: Although the differences in percent vital bone were not statistically significant among the 3 treatment groups in this pilot study, BG material was observed to act as an osteoconductive material which had a positive effect on socket healing at 6 to 8 months postextraction. Further research following implant placement in treated and control sockets is warranted to determine if bone implant contact is improved in BG-filled versus unfilled sockets.