Lateral Alveolar Ridge Augmentation with Autologous Dentin of Periodontally Compromised Teeth: A Retrospective Study.

Tooth shell technique (TST) using autologous dentine is possible with lateral ridge augmentation while avoiding a donor region. This study aimed to clarify whether the use of periodontally compromised teeth (PCT) leads to similar results compared to non-periodontally compromised teeth (NPCT). In this retrospective study, the dentin matrix of 41 patients (PCT: n = 19 with 29 implants; NPCT: n = 22, with 29 implants) was used for TST. All cases were re-examined. Outcome parameters were biological complications, horizontal hard tissue loss, osseointegration, and the integrity of the buccal lamella. Only in one case in the PCT group, a graft was lost. In three cases, minor complications were identified, including two cases of wound dehiscence and one case of inflammation with suppuration (PCT: n = 1, NPCT: n = 3). All implants, except the one with the severe complication, were osseointegrated and the integrity of the buccal bone lamella was preserved. Mean difference of the resorption of the crestal width and the buccal lamella did not differ statistically between the two groups. TST using PCT showed results comparable to those of NPCT in terms of complications and graft resorption. Processed dentin matrix from PCT can be used and applied with predictable results for bone grafting, utilizing TST.

Retrospective Study: Lateral Ridge Augmentation Using Autogenous Dentin: Tooth-Shell Technique vs. Bone-Shell Technique.

In the literature, autogenous dentin is considered a possible alternative to bone substitute materials and autologous bone for certain indications. The aim of this proof-of-concept study was to use autogenous dentin for lateral ridge augmentation. In the present retrospective study, autogenous dentin slices were obtained from teeth and used for the reconstruction of lateral ridge defects (tooth-shell technique (TST): 28 patients (15 females, 13 males) with 34 regions and 38 implants). The bone-shell technique (BST) according to Khoury (31 patients (16 females, 15 males) with 32 regions and 41 implants) on autogenous bone served as the control. Implants were placed simultaneously in both cases. Follow-up was made 3 months after implantation. Target parameters during this period were clinical complications, horizontal hard tissue loss, osseointegration, and integrity of the buccal lamella. The prosthetic restoration with a fixed denture was carried out after 5 months. The total observation period was 5 months. A total of seven complications occurred. Of these, three implants were affected by wound dehiscences (TST: 1, BST: 2) and four by inflammations (TST: 0, BST: 4). There were no significant differences between the two groups in terms of the total number of complications. One implant with TST exhibited a horizontal hard tissue loss of 1 mm and one with BST of 0.5 mm. Other implants were not affected by hard tissue loss. There were no significant differences between the two groups. Integrity of the buccal lamella was preserved in all implants. All implants were completely osseointegrated in TST and BST. All implants could be prosthetically restored with a fixed denture 5 months after augmentation. TST showed results comparable to those of the BST. Dentin can therefore serve as an alternative material to avoid bone harvesting procedures and thus reduce postoperative discomfort of patients.

BRAF V600E and Retinoic Acid in Radioiodine-Refractory Papillary Thyroid Cancer.

Radioiodine refractoriness in differentiated thyroid cancer remains an unsolved therapeutic problem. Response to retinoids might depend on specific genetic markers. In this retrospective analysis, associations between BRAF V600E and clinical outcomes after redifferentiation with retinoic acid (RA) and radioiodine therapy (RIT) were investigated. Thirteen patients with radioiodine-refractory (RAI-R) papillary thyroid cancer (PTC) were treated with 13-cis-RA followed by iodine-131 treatment at the Department of Endocrinology, Heidelberg University Hospital, Heidelberg, Germany. DNA sequencing was performed in formalin-fixed paraffin-embedded tissue. Clinical outcome parameters were tumor size, thyroglobulin, and radioiodine uptake in correlation to mutational status. Differences of each parameter were compared before and after RA/RIT. Initial response showed no difference in patients with BRAF V600E compared to patients with wild type. However, after a median follow-up of 2 and a half years, 2 out of 3 patients with BRAF V600E showed response compared to 5 out of 9 with wild type under consideration of all 3 parameters. In this small cohort, more RAI-R PTC patients with BRAF V600E receiving redifferentiation therapy showed response. Verification in a larger study population analyzing mutational status in patients with RAI-R PTC might be helpful to identify patients where redifferentiation therapy might lead to an improved outcome.