Comparison of ridge expansion and ridge splitting techniques for narrow alveolar ridge in a Swine cadaver model.

Ridge splitting and ridge expansion have been used to expand narrow alveolar ridges. Piezosurgical ridge splitting involves separating the atrophic crests with piezosurgical inserts. Ridge expansion with motor-driven expanders was proposed to achieve the cortical dilation. The purpose of this study was to evaluate the efficacy of ridge gain by ridge expansion or ridge splitting. Eighteen (36 ramus) swine cadaver jaws were first divided into two groups- ridge expansion with a motor-driven expander or ridge splitting with the piezosurgical system. Then, either an active-tapping implant or nonactivetapping cylinder-type implant was inserted. The crestal ridge diameter change was measured with a Boley gauge. The area of bony perforation, which includes fenestrations and dehiscences, was measured with a prefabricated reference grid. The results showed that there was no statistically significant difference in crestal width gain between groups. However, the combination of the motor-driven ridge expansion technique and the active-tapping implant could be beneficial in significantly decreasing the bony perforation area.

Periodontal probing calibration in an academic setting.

The purpose of this study was to locate the common discrepancy sites in a periodontal examination by new student dentists in a dental school setting and to evaluate student progress after one year of clinical training. Sixty-nine patients were enrolled in the initial phase of this study. Periodontal probing examinations were performed by both dental students and calibrated faculty members. A total of 9,171 sites were probed. Student-faculty agreement was then determined for each individual probing site. Frequency of agreement and average variance of agreement were calculated for each individual site probed. An identical procedure was conducted on thirteen patients by dental students after each had received one year of clinical training. A total of 1,991 sites were probed. Students new to the clinic had a significantly higher frequency of discrepancy in molars of all quadrants, with a trend of highest discrepancy shifting from mesial to distal sites when moving posteriorly in the posterior region. After one year of experience, there was a significant decline of discrepancy in all regions examined. More preclinical emphasis must be placed on proper probing technique to ensure accurate probing depths upon entry into the clinical setting.

The effect of cigarette smoking and native bone height on dental implants placed immediately in sinuses grafted by hydraulic condensation.

The purpose of this study was to determine the effect of cigarette smoking and residual native bone height on the survival of dental implants placed immediately in grafted sinuses. In this retrospective study, 334 subject records were screened, and 75 subjects (155 implants) were included. Data collection based on treatment notes and radiographs included age, sex, smoking status, sinus floor bone height, dental implant information, and implant survival. The survival rates of implants for nonsmokers and smokers at stage-two surgery were 93% and 84%, respectively. After 12 months of functional loading, the survival rates of implants for nonsmokers and smokers were 87% (81 of 93) and 79% (49 of 62), respectively (P < .000). Analysis revealed that the effect of smoking on implant survival is significant when the preoperative bone height is less than 4 mm, with an 82.4% implant survival rate in nonsmokers compared to 60% in smokers (P < .05). Smoking should be considered as a high risk factor when implants are placed immediately in grafted sinuses, particularly in areas of limited bone height.

The negative effect of combining rhBMP-2 and Bio-Oss on bone formation for maxillary sinus augmentation.

Sinus augmentation with various bone graft materials may be required in the posterior maxilla. This study compared bone formation in a lateral window sinus augmentation with recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ACS) combined with Bio-Oss or Bio-Oss graft alone. Patients were assigned to treatment with either rhBMP-2/ACS + Bio-Oss or Bio-Oss alone. After a healing period, bone cores were harvested. Histologic specimens demonstrated that new bone formation was less in those who received rhBMP-2/ACS + Bio-Oss than those with Bio-Oss alone. This study indicated that the addition of rhBMP-2/ACS to Bio-Oss has a negative effect on bone formation.

Regenerative periodontal therapy.

Traditional treatment for loss of bone and attachment due to periodontal disease has focused around repairing the damage induced. However, over the past few decades, clinicians have begun to utilize regenerative techniques to rebuild bone, cementum and the periodontal ligament. Conventional procedures most often involve the use of barrier membranes with bone grafts that foster selective cell repopulation and regrowth of osseous structures. Since the predictability of these techniques may be limited to certain case types, pharmacologically based efforts are underway to investigate the possibility of harnessing osseous regrowth potential. Clinical research has found that proteins are potent biological mediators that promote many of the events in wound healing, and have been shown to promote bone formation in human clinical studies.

Controlled hydrostatic sinus elevation: a novel method of elevating the sinus membrane.

Maxillary sinus elevation surgery has been practiced successfully over the past several decades with good outcomes, but tears and perforations still occur in significant numbers. The presumed cause of these problems is the fact that all methods currently used place "point sources" of lifting pressure on the Schneiderian membrane. A new procedure, controlled hydrostatic sinus lift, is presented herein as a safer, more controlled "lifting pressure" which simultaneously places equal force per square millimeter of bone-membrane interface. Hydraulic pressure in a closed system places equal pressure on all surfaces within the system, thereby eliminating "point sources" of pressure and gently elevating the Schneiderian membrane equally at all points of attachment. This controlled hydrostatic sinus lift procedure is accomplished by using a calibrated, hand-controlled pump and in-line pressure sensor meter.

An interarch alveolar ridge relationship classification.

Alveolar ridge defects resulting from tooth loss, trauma, periodontal disease, or congenital lesions often require correction prior to dental implant therapy. Numerous classifications proposed to describe alveolar ridge defects have been limited to describe intra-arch relationships. To provide sufficient jaw-to-jaw alveolar ridge (interarch) relationship information for both restorative and surgical treatment decision-making, this article introduces a new interarch alveolar ridge relationship classification system. This article also discusses cone beam computed tomography and multidisciplinary treatment planning options for approaching each classification.