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.

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.

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.