Clinical assessment of peri-implant tissues in patients with varying severity of chronic periodontitis

Purpose: This retrospective study assessed the health of peri-implant tissues in patients with varying severity of chronic periodontitis.
Materials and Methods: Sixty-one subjects aged 44 to 70 years (median age 58 years) were recruited. Based on severity of periodontitis, 31 subjects were classified as having severe generalized chronic periodontitis, and the remaining 30 subjects had mild or no periodontitis. Social and medical histories were obtained from each patient. A comprehensive periodontal examination included: plaque index, gingival index, bleeding index, probing depth, clinical attachment level, and radiographic bone loss. Data were analyzed using Fisher's exact and chi-square tests for categorical variables, and t -test for continuous variables.
Results: There was a statistically significant greater loss of attachment ( p  < .05) around implants in the group with severe periodontitis compared to the no/mild periodontitis group.
Conclusion: Because of the greater loss of clinical attachment around implants placed in patients with generalized severe chronic periodontitis, close monitoring of these patients is suggested to prevent both development of peri-implantitis and recurrence of periodontal infection.     

Effects of transforming growth factor beta1 (TGFbeta-1) and dentin non-collagenous proteins (DNCP) on human embryonic ectomesenchymal cells in a three-dimensional culture system

Cranial neural crest-derived ectomesenchymal cells represent a population of pluripotent stem cells giving rise to many of the various oro-facial and dental tissues. The factors determining the terminal fate of these cells are still unclear. The potentiality of human embryonic ectomesenchymal cells from the first branchial arch have been investigated when isolated and grown in a three-dimensional (3D)-collagen gel culture system in the presence of dentin matrix-derived non-collagenous proteins (DNCP) and TGFbeta-1. Functional differentiation of cells showing some characteristics of odontoblast-like cells could be observed when the cells were cultured with DNCP+TGFbeta-1 or DNCP, however, only cytological differentiation was observed during culture with TGFbeta-1 alone. The characteristics of these cells was assessed by morphological appearance, expression of the odontoblast phenotype marker dentin sialophosphoprotein (DSPP), increased alkaline phosphatase levels and formation of mineralised nodules in vitro. The results indicate that these embryonic cells from the first branchial arch are capable of responding to the inductive stimulus of DNCP or DNCP+TGFbeta-1 when isolated and grown in the 3D collagen gel culture system. The capacity of the isolated cells to differentiate into mineralizing cells showing some characteristics of odontoblast-like cells under these growth conditions highlights the potential of such approaches for tissue engineering strategies for hard-tissue regeneration after injury.     

Dentin adhesion and microleakage of a resin-based calcium phosphate pulp capping and basing cement

An experimental resin-based bioactive calcium phosphate cement, intended as a pulp capping and basing material, was evaluated for dentin shear bond strength and microleakage. The interfacial morphology was examined by scanning electron microscopy (SEM). For microleakage, dentin cavities without (Group A) or after (Group B) acid etching were restored with the calcium phosphate cement. A resin-based calcium hydroxide (VLC Dycal; Group C) was used as control material according to the manufacturer's instructions. After water storage and thermocycling, the microleakage was scored using a AgNO(3) staining procedure. For the shear bond strength, flat exposed dentin surfaces were treated as for the microleakage test. Metal irises pressed against the dentin surface were filled with the cements, which were photocured. Both tests were carried out after 1 wk. While acid etching did not result in significantly greater microleakage, it led to higher shear bond strength, and allowed, as shown by SEM, the formation of a hybrid layer and resin tags. Both groups treated with the calcium phosphate cement had significantly lower microleakage scores and higher mean shear bond strength values than the groups treated with the control material.     

Oncocytoid artifact of the parotid gland: A newly reported artifact

Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common in parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases.     

A CAD-CAM Ceramic Inlay Technique

This article details the technique of a Cerec computer-aided designed (CAD) and computer-aided manufactured (CAM) inlay. Using a ceramic material the unit can mill an inlay from an optical "impression" that is then bonded to place using a dual-cure composite resin cement.     

Management of Periodontal Tissues for Restorative Dentistry

Proper management of periodontal tissues is required to achieve predictable long-term success with restorative dental procedures. Forced eruption as well as several surgical techniques may be used to achieve and maintain adequate biologic width during restorative and esthetic dental procedures. The technique that will yield optimal results depends on the relationship between the restoration's margins and the surrounding periodontium. A classification system that describes these interrelationships and provides treatment recommendations is included.     

Factors influencing the cost-effectiveness of community health center dental programs in the U. S. A.

abstract The community health center has been viewed by many Americans as an important mechanism for the improvement of health of the urban poor. The millions of dollars allocated for a relatively small percentage of the population, however, has led to some criticisms of the concept. This paper deals with factors influencing the cost of dental services in a community health center and an analysis of several existing programs. The major factors affecting the cost effectiveness of the clinics appear to be the (1) broken appointment rate, (2) age distribution of the population served, (3) mixture of services rendered, and (4) additional community services rendered. Programs which have low broken appointment rates and which treat both adults and children seem to maintain a higher revenue-cost ratio. This ratio was in the range of 0.78 to 1.10 for the three dental programs studied.     

Spring-mediated mandibular distraction osteogenesis

Successful performance of distraction osteogenesis requires rigorous patient compliance with a daily activation regimen of a percutaneous screw. Previous clinical studies have found that failure of patient compliance with this regimen is the most common complication leading to technical failure of the distraction process. The authors have developed an internalized spring-mediated device for mandibular distraction osteogenesis that can potentially abrogate the risks associated with patient compliance by allowing for automated distraction across an osteotomy. Twenty adult New Zealand White rabbits underwent unilateral mandibular osteotomy. A segment of nickel-titanium shape memory alloy reinforced at both ends with a pinball was fashioned into an inferiorly based arc and secured to the mandible with stainless steel wire. On postoperative day 12, spring activation commenced by cutting a wire binding the two pinballs to one another. Animals were observed for 6 weeks before they were killed. Radiographic studies and decalcified histologic analysis were performed on extracted mandibles. Temperature- and displacement-dependent properties of the shape memory alloy were also examined. Five animals were excluded from the study due to infection, nonunion, or device failure. A mean distraction of 1.2 mm in the distracted hemimandible relative to the nonoperated hemimandible was found (P <.001, two-tailed paired t test). The maximum distraction achieved in an experimental specimen using the spring distractor was 3.7 mm. There were no other histologic or radiographic differences found between study specimens and specimens subjected to traditional distraction methods. Biomechanical testing of the shape memory alloy revealed a temperature-dependent increase in force at body temperature compared with room temperature and a reduction in force with increased displacement of the spring. This study demonstrates the feasibility of spring-mediated distraction osteogenesis across an osteotomy. As the field of distraction osteogenesis matures, the next level of sophistication in the clinical development of devices will incorporate technology that permits fully internalized and automated distraction to occur.     

Periodontal disease: links with serum lipid/ triglyceride levels? Review and new data

Evidence now supports an intriguing role for serum lipids/triglycerides in modulation of the host immune response to infection. This paper will review the studies that have been conducted in humans and various animal models of the association between elevated serum lipids/triglycerides (i.e. hyperlipidaemia) and periodontitis (PD). We will also present new data in rats that suggests a bi-directional relationship between hyperlipidaemia and PD, i.e. that PD itself may be able to modulate serum lipid levels. This review will introduce evidence from other studies that the type of dietary lipids is important in the modulation of the immune/inflammatory response. Overall, the studies presented herein suggest that further investigation using epidemiological and experimental approaches is warranted.     

Sleep disturbances in 22q11.2 deletion syndrome: a case with obstructive and central sleep apnea.

The 22q11.2 deletion syndrome is characterized by wide phenotypic variability, frequently involving characteristic craniofacial features, cardiac malformations, and learning difficulties. Skeletal anomalies are also common and include an obtuse angle of the cranial base, retrognathia, and cervical spine abnormalities. Despite these anomalies, sleep-disturbed breathing is not reported frequently in patients with 22q11.2 deletion syndrome. We describe a patient with an obstructive sleep disturbance that was successfully treated with a tonsillectomy followed by mandibular distraction osteogenesis. She also had central sleep apnea, initially attributed to spinal cord impingement from cervical instability. Posterior cervical fusion was associated with a decrease in the number of central apneic events.