Piezosurgery prevents brain tissue damage: an experimental study on a new rat model

Piezosurgery is a promising meticulous system for bone cutting, based on ultrasound microvibrations. It is thought that the impact of piezosurgery on the integrity of soft tissue is generally low, but it has not been examined critically. The authors undertook an experimental study to evaluate the brain tissue response to skull bone removal using piezosurgery compared with a conventional drilling method. In Wistar male rats, a circular bone window was drilled to the parietal bone using piezosurgery on one side and a conventional bone drill on the other side. The behavioural performance of animals was evaluated using the motor BBB test and sensory plantar test. The brains of animals were evaluated by magnetic resonance imaging (MRI) and histology. The results of MRI showed significantly increased depth and width of the brain lesion in the region of conventional drilling compared with the region where piezosurgery was used. Cresylviolet and NF 160 staining confirmed these findings. There was no significant difference in any of the behavioural tests between the two groups. In conclusion, piezosurgery is a safe method for the performance of osteotomy in close relation to soft tissue, including an extremely injury-sensitive tissue such as brain.     

Surgical lasers and hard dental tissue

The cutting of dental hard tissue during restorative procedures presents considerable demands on the ability to selectively remove diseased carious tissue, obtain outline and retention form and maintain the integrity of supporting tooth tissue without structural weakening. In addition, the requirement to preserve healthy tissue and prevent further breakdown of the restoration places the choice of instrumentation and clinical technique as prime factors for the dental surgeon. The quest for an alternative treatment modality to the conventional dental turbine has been, essentially, patient-driven and has led to the development of various mechanical and chemical devices. The review of the literature has endorsed the beneficial effects of current laser machines. However utopian, there is additional evidence to support the development of ultra-short (nano- and femto-second) pulsed lasers that are stable in use and commercially viable, to deliver more efficient hard tissue ablation with less risk of collateral thermal damage. This paper explores the interaction of laser energy with dental hard tissues and bone and the integration of current laser wavelengths into restorative and surgical dentistry.     

Surgical guided tissue regeneration treatment of advanced periodontal defects: a 5-year follow-up study

OBJECTIVES: To study the 5-year outcome of combined use of guided tissue regeneration (GTR) barriers and bovine bone in advanced periodontal defects. MATERIAL AND METHODS: In each of 24 patients, one defect was surgically exposed, debrided, filled with bovine bone, and covered with a bioresorbable barrier. Re-examinations were made after 1, 3, and 5 years. RESULTS: Average full-mouth plaque scores (FMPS) were 14.5% at baseline and 10.7%, 9.8%, and 18.9% after 1, 3, and 5 years, respectively. Mean probing pocket depth (PPD) was 10.0 mm at baseline. Mean PPD reduction was 5.2 mm after 1 year, 5.6 mm after 3 years, and 5.3 mm after 5 years. Mean gingival recession was 1.0 mm after 1 year, 1.6 mm after 3 years, and 1.3 mm after 5 years. Mean gain in clinical attachment level (CAL) was 4.2 mm at the 1-year, 4.1 mm at the 3-year, and 4.3 mm at the 5-year examination. Smoking significantly influenced CAL change at all re-examinations. FMPS were significantly correlated with radiographic defect depth at the 5-year examination and CAL with smoking and FMPS at the 3-year examination. CONCLUSION: Advanced periodontal defects can be successfully treated with the combined use of GTR barriers and bovine bone to substantially reduce PPD and achieve a stable, long-term gain of CAL.     

Surgical reconstruction of interdental papilla using an interposed subepithelial connective tissue graft: a case report

The unpredictability of current surgical procedures for papilla reconstruction has been a matter of concern for both periodontists and patients. This case report presents a complete papilla reconstruction in a 20-year-old woman using an interposed subepithelial connective tissue graft. The results show that this technique can be successfully used in treating the loss of papillae and achieving long-term stability. The objective of this report is to describe the surgical technique and comment on the factors that may have influenced the final result.     

Surgical reconstruction of interdental papilla using an interposed subepithelial connective tissue graft: a case report

The unpredictability of current surgical procedures for papilla reconstruction has been a matter of concern for both periodontists and patients. This case report presents a complete papilla reconstruction in a 20-year-old woman using an interposed subepithelial connective tissue graft. The results show that this technique can be successfully used in treating the loss of papillae and achieving long-term stability. The objective of this report is to describe the surgical technique and comment on the factors that may have influenced the final result.—Reprinted with permission of Quintessence Publishing.     

Bacteraemia and tissue damage resulting from air polishing

This study investigates the production of bacteraemia in dental prophylaxis by use of a commercially available air polishing device. Prophylaxis by means of the conventional rubber cup and paste method was used as a control. The study showed that air polishing can result in loss of epithelium at the gingival margin. The likelihood of a bacteraemia resulting from air polishing, in the absence of gingivitis, was less than in the group undergoing conventional prophylaxis. Although a higher number of bacteraemias was seen in the control group, the difference between the two groups was not statistically significant. Results indicate that patients who are at risk continue to require antibiotic cover.     

Surgical wafers: a comparative study

A comparative study of occlusal wafers for orthognathic surgery made for 185 orthognathic surgery patients with the mean age of 24.4+/-4.3 years is presented. This study is intended to highlight any wafer-associated surgical problems, which determine wafer design. Various types of occlusal wafers were used during the period of this review, but in most of the cases a simple quick-cure acrylic wafer was found to be most satisfactory. However, some difficult patients with cleft palates or neuromuscular disorders may require wafers of a novel design and material.     

Oronasal communication caused by a denture with suction cup: a case report.

Suction cups, which provide high retention, are not being recommended anymore because of the destructive effect of the negative pressure on the palatal tissues. It is known that dentures with suction cups can cause perforations in the palate. In this case report, an oronasal communication caused by a denture with suction cup in a patient who had previously undergone pleomorphic adenoma excision of the palate is presented. Disadvantages of suction cups are emphasized.     

Deficiency of iNOS contributes to Porphyromonas gingivalis-induced tissue damage

Periodontitis is a chronic inflammatory disease that results in extensive soft and hard tissue destruction of the periodontium. Porphyromonas gingivalis possesses an array of virulence factors and has been shown to induce expression of inducible nitric oxide synthase (iNOS) in inflammatory cells. The aim of this study was to investigate the effect of eliminating iNOS in a murine model of P. gingivalis infection. This was achieved by utilizing a P. gingivalis-induced skin abscess model, and an alveolar bone loss model employing an oral infection of P. gingivalis in iNOS knockout mice. The results indicated that iNOS knockout mice exhibit more extensive soft tissue damage and alveolar bone loss in response to P. gingivalis infection compared to wild-type mice. The local immune response to P. gingivalis in iNOS knockout mice was characterized by increased numbers of polymorphonuclear monocytes, while the systemic immune response was characterized by high levels of interleukin-12. The iNOS is required for an appropriate response to P. gingivalis infection.